Surprisingly high specificity of the PPD skin test for M. tuberculosis infection from recent exposure in The Gambia.

Science.gov (United States)

Hill, Philip C; Brookes, Roger H; Fox, Annette; Jackson-Sillah, Dolly; Lugos, Moses D; Jeffries, David J; Donkor, Simon A; Adegbola, Richard A; McAdam, Keith P W J

2006-12-20

Options for intervention against Mycobacterium tuberculosis infection are limited by the diagnostic tools available. The Purified Protein Derivative (PPD) skin test is thought to be non-specific, especially in tropical settings. We compared the PPD skin test with an ELISPOT test in The Gambia. Household contacts over six months of age of sputum smear positive TB cases and community controls were recruited. They underwent a PPD skin test and an ELISPOT test for the T cell response to PPD and ESAT-6/CFP10 antigens. Responsiveness to M. tuberculosis exposure was analysed according to sleeping proximity to an index case using logistic regression. 615 household contacts and 105 community controls were recruited. All three tests assessed increased significantly in positivity with increasing M. tuberculosis exposure, the PPD skin test most dramatically (OR 15.7; 95% CI 6.6-35.3). While the PPD skin test positivity continued to trend downwards in the community with increasing distance from a known case (61.9% to 14.3%), the PPD and ESAT-6/CFP-10 ELISPOT positivity did not. The PPD skin test was more in agreement with ESAT-6/CFP-10 ELISPOT (75%, p = 0.01) than the PPD ELISPOT (53%, pPPD skin test positive increased (pPPD skin test negative decreased (pPPD skin test has surprisingly high specificity for M. tuberculosis infection from recent exposure in The Gambia. In this setting, anti-tuberculous prophylaxis in PPD skin test positive individuals should be revisited.

Allergy Skin Tests

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... and symptoms. Medications can interfere with results Before scheduling a skin test, bring your doctor a list ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

Tuberculin Skin Testing

Science.gov (United States)

... Appendix 1 Appendix 2 Appendix 3 Interim Laboratory Biosafety Guidance for XDR Mycobacterium tuberculosis strains Data & Statistics ... The Mantoux tuberculin skin test (TST) is the standard method of determining whether a person is infected ...

Ethnic differences in objective and subjective skin irritation response: an international study.

Science.gov (United States)

Lee, E; Kim, S; Lee, J; Cho, S-A; Shin, K

2014-08-01

Due to global marketing in the cosmetics industry, it is important to assess ethnic population susceptibility when evaluating the safety of cosmetic products or chemicals. To investigate ethnic variations in skin irritation response to positive irritants. Clinical testing was performed in four countries on two ethnic groups - Asian and Caucasian. We performed patch tests on the subjects' back with 0.5% aqueous sodium lauryl sulfate (SLS) and 0.15% retinol prepared in 1,3-butylene glycol. Stinging tests were performed using 5% aqueous lactic acid and 0.001% (w/v) capsaicin prepared in 10% ethanol solution separately. The incidence of self-perceived skin sensitivity was similar in the two ethnic groups. However, the incidence of adverse skin reaction to cosmetics appeared significantly higher in Asian (33.0%) than in Caucasian subjects (11.3%). For standard positive irritants such as 0.5% aqueous SLS solution, Asian subjects showed significantly higher scores than Caucasian subjects. The incidence of positive reaction to the 0.15% retinol patch test tended to be higher in Asian than in Caucasian subjects. Our data also showed that neurosensitivity to 5% lactic acid and 0.001% capsaicin was higher in Asian than in Caucasian subjects. Although self-reported skin sensitivity does not appear to differ according to ethnicity, there are ethnic differences in objective and subjective skin irritation responses to several standard positive materials. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Assessment of a Protein Cocktail-Based Skin Test for Bovine Tuberculosis in a Double-Blind Field Test in Cattle

Science.gov (United States)

Xin, Ting; Jia, Hong; Ding, Jiabo; Li, Pingjun; Yang, Hongjun; Hou, Shaohua; Yuan, Weifeng; Guo, Xiaoyu; Wang, Haichun; Liang, Qianqian; Li, Ming

2013-01-01

responses correlate to traditional measures of bovine TB evaluation, including skin test and gamma interferon release assay. PMID:23365203

Mechanical response of human female breast skin under uniaxial stretching.

Science.gov (United States)

Kumaraswamy, N; Khatam, Hamed; Reece, Gregory P; Fingeret, Michelle C; Markey, Mia K; Ravi-Chandar, Krishnaswamy

2017-10-01

Skin is a complex material covering the entire surface of the human body. Studying the mechanical properties of skin to calibrate a constitutive model is of great importance to many applications such as plastic or cosmetic surgery and treatment of skin-based diseases like decubitus ulcers. The main objective of the present study was to identify and calibrate an appropriate material constitutive model for skin and establish certain universal properties that are independent of patient-specific variability. We performed uniaxial tests performed on breast skin specimens freshly harvested during mastectomy. Two different constitutive models - one phenomenological and another microstructurally inspired - were used to interpret the mechanical responses observed in the experiments. Remarkably, we found that the model parameters that characterize dependence on previous maximum stretch (or preconditioning) exhibited specimen-independent universal behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Lönnqvist, Susanna; Briheim, Kristina; Kratz, Gunnar

2016-02-01

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

Delayed-type hypersensitivity skin test responses to PPD and other antigens among BCG-vaccinated HIV-1-infected and healthy children and adolescents.

Science.gov (United States)

Costa, Natalia Moriya Xavierda; Albuquerque, Maly de; Lins, Janaína Bacelar Acioli; Alvares-Junior, João Teixeira; Stefani, Mariane Martins de Araújo

2011-10-01

Among HIV-1-infected patients, CD4+ T cell counts are well-established markers of cell-mediated immunity. Delayed-type hypersensitivity (DTH) skin tests can be used to evaluate in vivo cell-mediated immunity to common antigens. DTH responses to tuberculin purified protein derivative (PPD), sporotrichin, trichophytin, candidin and streptokinase/streptodornase antigens were assessed. Thirty-six HIV-1-infected children/adolescents and 56 age- and sex-matched HIV-1/HIV-2-seronegative participants were tested. All participants had a BCG scar. Fisher's exact test was used to evaluate significant differences between groups (pPPD positivity prevailed among healthy participants (40/56, 71.4%). PPD reactivity in the HIV-1-positive group was 8.3% (pPPD induration was 2.5mm (range: 2-5mm) in the HIV-1 group and 6.0 mm among healthy participants (range: 3-15 mm). There was no correlation between PPD positivity and age. No correlation between CD4+ T cell counts and DTH reactivity was observed among HIV-1-infected patients. DTH skin test responses, including PPD reactivity, were significantly lower among HIV-1-infected participants compared to healthy controls, which likely reflects advanced disease and T cell depletion.

Deceased donor skin allograft banking: Response and utilization

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Gore Madhuri

2010-10-01

Full Text Available Background: In the absence of xenograft and biosynthetic skin substitutes, deceased donor skin allografts is a feasible option for saving life of patient with extensive burn injury in our country. Aims: The first deceased donor skin allograft bank in India became functional at Lokmanya Tilak Municipal (LTM medical college and hospital on 24 th April 2000. The response of Indian society to this new concept of skin donation after death and the pattern of utilization of banked allografts from 2000 to 2010 has been presented in this study. Settings and Design: This allograft skin bank was established by the department of surgery. The departments of surgery and microbiology share the responsibility of smooth functioning of the bank. Materials and Methods: The response in terms of number of donations and the profile of donors was analyzed from records. Pattern and outcome of allograft utilization was studied from specially designed forms. Results: During these ten years, 262 deceased donor skin allograft donations were received. The response showed significant improvement after counselling was extended to the community. Majority of the donors were above 70 years of age and procurement was done at home for most. Skin allografts from 249 donors were used for 165 patients in ten years. The outcome was encouraging with seven deaths in 151 recipients with burn injuries. Conclusions: Our experience shows that the Indian society is ready to accept the concept of skin donation after death. Use of skin allografts is life saving for large burns. We need to prepare guidelines for the establishment of more skin banks in the country.

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

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Zhiqiang Song

Full Text Available BACKGROUND: Chronic spontaneous urticaria (CSU is a common skin disorder with etiology that is not well understood. METHODS: In this study, we evaluated the prevalence of autologous serum skin test (ASST and skin prick testing (SPT to house dust mite (HDM in 862 CSU cases in China. Clinical features, courses and treatment responses were also recorded. RESULTS: The prevalence of positive ASST was 46.3%, and patients aged 30-39 years had the highest positive rate (52.1%. Positive SPT to HDM was seen in 153 patients (17.7% with the highest positive rate (34.2% in patients aged 20 or less. Patients with positive ASST had higher urticaria activity scores (UAS (4.18±0.65 vs. 3.67±0.53 but lower positive rates of HDM (24.6% vs. 37.6%, as compared with those with negative ASST (odds ratio (OR 1.84, 95% CI 1.38-2.47. Patients could be categorized into four groups based on the results of ASST and SPT to HDM and patients with positive ASST and positive SPT to HDM had the highest disease activity scores, experienced higher frequencies of angioedema, diseases duration, and required higher dosage of loratadine every month, compared with other subgroups (P<0.0001. CONCLUSIONS: Patients with CSU showed varied responses of positive ASST and varied sensitivity to HDM, Patients with positive ASST and/or positive SPT had more disease activity compared with patients with negative ASST and/or negative SPT. Further classification can be made based on the result of SPT and ASST.

The use of ex vivo human skin tissue for genotoxicity testing

Energy Technology Data Exchange (ETDEWEB)

Reus, Astrid A.; Usta, Mustafa [TNO Triskelion BV, Utrechtseweg 48, 3704 HE, Zeist (Netherlands); Krul, Cyrille A.M., E-mail: cyrille.krul@tno.nl [TNO, Utrechtseweg 48, 3704 HE Zeist (Netherlands)

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

The use of ex vivo human skin tissue for genotoxicity testing

International Nuclear Information System (INIS)

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

2012-01-01

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

Comparison of Tuberculin Skin Test result and interferon gamma response to human PPD in BCG scar positive and negative children.

Science.gov (United States)

Sayyahfar, Shirin; Karimi, Abdollah; Fahimzad, Alireza; Shamshiri, Ahmad Reza

2014-03-01

The aim of this study is to compare Tuberculin Skin Test (TST) result and interferon gamma response to human PPD (purified protein derivative), in scar positive and scar negative BCG-vaccinated children. Between August 2007 and May 2008 a total of 236 children aged 1-168 months (mean 21 months) admitted to Mofid Children's Hospital, Tehran, Iran, were enrolled in a cross-sectional study. Each patient was examined for BCG vaccine scar and tested with TST and human PPD-based Interferon Gamma Release Assay (IGRA). Two hundred and twenty one cases out of 236 (44% female, 1-168 months, mean age 21 months) were scar positive of whom 95% TST result was negative. Human PPD-based IGRA was positive in 110 (49.8%), negative in 85 (38.4 %) and indeterminate in 26 (11.8%) of scar positive patients. Fifteen children (40% female, 1-156 months; mean age 42 months) were scar negative. All the scar negative cases were TST negative. Human PPD-based IGRA was positive in 10 (66.7%), negative in 4 (26.7%) and indeterminate in 1 (6.7%) of scar negative patients. Immune responsiveness to human PPD antigens in scar positive and negative children may not correspond with results of the Tuberculin Skin Test. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

Sympathetic skin response evoked by laser skin stimulation

OpenAIRE

Rossi, P.; Truini, A.; Serrao, M.; Iannetti, G. D.; Parisi, L.; Pozzessere, G.; Cruccu, G.

2002-01-01

The objective of this study was to evoke sympathetic skin responses (SSRs) in healthy subjects using laser stimulation and to compare these responses with those induced by conventional electrical stimuli. Twenty healthy subjects were investigated. SSRs were obtained using electrical and laser stimuli delivered to the wrist controlateral to the recording site. The sympathetic sudomotor conduction velocity (SSFCV) was measured in 8 subjects by simultaneously recording the SSR from the hand and ...

[Skin cell response after jellyfish sting].

Science.gov (United States)

Adamicová, Katarína; Výbohová, Desanka; Fetisovová, Želmíra; Nováková, Elena; Mellová, Yvetta

2016-01-01

Jellyfish burning is not commonly part of the professional finding in the central Europe health care laboratory. Holiday seaside tourism includes different and unusual presentations of diseases for our worklplaces. Sea water-sports and leisure is commonly connected with jellyfish burning and changes in the skin, that are not precisely described. Authors focused their research on detection of morphological and quantitative changes of some inflammatory cells in the skin biopsy of a 59-years-old woman ten days after a jellyfish stinging. Because of a comparison of findings the biopsy was performed in the skin with lesional and nonlesional skin. Both excisions of the skin were tested by imunohistochemical methods to detect CD68, CD163, CD30, CD4, CD3, CD8, CD20 a CD1a, to detect histiocytes, as well as several clones of lymphocytes and Langerhans cells (antigen presenting cells of skin), CD 117, toluidin blue and chloracetase esterase to detect mastocytes and neutrophils. Material was tested by immunofluorescent methods to detect IgA, IgM, IgG, C3, C4, albumin and fibrinogen. Representative view-fields were documented by microscope photocamera Leica DFC 420 C. Registered photos from both samples of the skin were processed by morphometrical analysis by the Vision Assistant software. A student t-test was used for statistical analysis of reached results. Mean values of individual found cells in the sample with lesion and without lesion were as follows: CD117 -2.64/0.37, CD68-6.86/1.63, CD163-3.13/2.23, CD30-1.36/0.02, CD4-3.51/0.32, CD8-8.22/0.50, CD3-10.69/0.66, CD20-0.56/0.66, CD1a-7.97/0.47 respectively. Generally mild elevation of eosinofils in lesional skin was detected. Increased values of tested cells seen in excision from lesional skin when compared with nonlesional ones were statistically significant in eight case at the level p = 0.033 to 0.001. A not statistically significant difference was found only in the group of CD163+ histiocytes. Authors detected numbers

Radiation response of skin in young and old rats

Energy Technology Data Exchange (ETDEWEB)

Hamlet, R.; Hopewell, J.W. (Churchill Hospital, Oxford (UK))

1982-11-01

The results of this investigation clearly demonstrate the different radiation skin response in rats of differing ages. The reasons for these differences cannot be clarified until cell kinetic studies have been completed. These results obtained for rodent skin would appear to be in disagreement with the available data for human skin (Rubin and Casarett 1968) where no marked age-related changes were reported. Also, in pig skin studies (Hopewell and Young 1982) there was no evidence of an age effect in the dermal vascular response in 3-12-month-old animals. This may be related to the different tissue being investigated or it may reflect important species differences. Whatever the reasons behind these observations, the different skin response to radiation in rats of 7, 14 and 52 weeks of age has clearly been demonstrated and should be borne in mind when extrapolating data with rodent skin to the clinical situation.

Skin graft viability test

International Nuclear Information System (INIS)

Wahner, H.W.; Robertson, J.S.

1983-01-01

With respect to skin pedicles (tubular pedicle or direct flap), an estimation of the blood supply is of great importance in making a decision as to when to perform the separation from the original blood supply. This decision is based on empiric observation of the normal time of healing and varies greatly with the site and the concepts of the individual surgery. A number of methods have been proposed for testing the circulation of pedicle skin flaps or tubes, and these methods all seem more complicated and less accurate than the isotope method that is described in this chapter

Thermoregulatory responses to skin wetting during prolonged treadmill running.

Science.gov (United States)

Bassett, D R; Nagle, F J; Mookerjee, S; Darr, K C; Ng, A V; Voss, S G; Napp, J P

1987-02-01

We examined the physiological responses to skin wetting during a 120-min level treadmill run to assess whether skin wetting would reduce the dehydration and the increase in core temperature associated with prolonged exercise. Testing was conducted in an environmental chamber (T = 29.5 degrees C, wind velocity = 3 m X sec-1) under two different humidity conditions (33 or 66% relative humidity). Ten male subjects performed two runs in each humidity condition; one served as a control run. The other included spraying the body with 50 ml of water (T = 29.5 degrees C) every 10 min. Spraying had no effect on rectal temperature (Tre), heart rate, oxygen consumption, perceived exertion, sweat loss, or percent change in plasma volume in both the humid and the dry conditions. Spraying produced a significant reduction in mean skin temperature (Tsk), which increased the (Tre - Tsk) gradient. At the same time, overall skin conductance (K) was decreased, presumably as a result of cutaneous vasoconstriction due to the low Tsk. Since heat transfer from the body's core to the skin is expressed by the equation: heat transfer = K X (Tre - Tsk) the spraying had no effect on heat transfer away from the core, and Tre remained unchanged.

Biodegradable Polymers Induce CD54 on THP-1 Cells in Skin Sensitization Test.

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Jung, Yeon Suk; Kato, Reiko; Tsuchiya, Toshie

2011-01-01

Currently, nonanimal methods of skin sensitization testing for various chemicals, biodegradable polymers, and biomaterials are being developed in the hope of eliminating the use of animals. The human cell line activation test (h-CLAT) is a skin sensitization assessment that mimics the functions of dendritic cells (DCs). DCs are specialized antigen-presenting cells, and they interact with T cells and B cells to initiate immune responses. Phenotypic changes in DCs, such as the production of CD86 and CD54 and internalization of MHC class II molecules, have become focal points of the skin sensitization test. In this study, we used h-CLAT to assess the effects of biodegradable polymers. The results showed that several biodegradable polymers increased the expression of CD54, and the relative skin sensitizing abilities of biodegradable polymers were PLLG (75 : 25) < PLLC (40 : 60) < PLGA (50 : 50) < PCG (50 : 50). These results may contribute to the creation of new guidelines for the use of biodegradable polymers in scaffolds or allergenic hazards.

Biodegradable Polymers Induce CD54 on THP-1 Cells in Skin Sensitization Test

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Yeon Suk Jung

2011-01-01

Full Text Available Currently, nonanimal methods of skin sensitization testing for various chemicals, biodegradable polymers, and biomaterials are being developed in the hope of eliminating the use of animals. The human cell line activation test (h-CLAT is a skin sensitization assessment that mimics the functions of dendritic cells (DCs. DCs are specialized antigen-presenting cells, and they interact with T cells and B cells to initiate immune responses. Phenotypic changes in DCs, such as the production of CD86 and CD54 and internalization of MHC class II molecules, have become focal points of the skin sensitization test. In this study, we used h-CLAT to assess the effects of biodegradable polymers. The results showed that several biodegradable polymers increased the expression of CD54, and the relative skin sensitizing abilities of biodegradable polymers were PLLG (75 : 25 < PLLC (40 : 60 < PLGA (50 : 50 < PCG (50 : 50. These results may contribute to the creation of new guidelines for the use of biodegradable polymers in scaffolds or allergenic hazards.

Assessment of the respiratory metabolism in the skin from transcutaneous measurements of pO2 and pCO2: potential for non-invasive monitoring of response to tuberculin skin testing.

Science.gov (United States)

Abbot, N C; Spence, V A; Swanson-Beck, J; Carnochan, F M; Gibbs, J H; Lowe, J G

1990-03-01

A method is described for non-invasive transcutaneous (tc) measurement of tissue respiratory gas tensions in the skin on the forearm for study of delayed hypersensitivity reactions in man. Steady state values for tcpO2 and tcpCO2 were measured, and the skin respiratory rate (oxygen consumption) and the tissue pH were estimated from the changes in tcpO2 and tcpCO2 observed after interruption of the arterial circulation by cuff occlusion for 4 minutes. The extent of within-experiment and between subject variation in the steady-state measurements was not great (coefficient of variation 10%): tcpCO2.ss (steady state) was higher in men and tcpO2.ss was higher in women, but the extent of these sex differences was also small. Reference ranges have been established for tc measurements and calculated indices of tissue respiration in the undisturbed forearm skin of normal volunteers, against which the changes induced by tuberculin testing can be assessed. Severe changes, indicative of profound hypoxia and acidosis, are seen in intense delayed hypersensitivity reactions. Similar, but less severe changes were seen at the site of skin tests on BCG-vaccinated subjects who were 'negative' by conventional criteria of measurement of dermal induration and they became greatly exaggerated after successful re-vaccination. Intradermal injection of saline did not induce hypoxia or local acidosis. These new methods are very sensitive indicators of the tissue response in the DHS reaction.

Evaluation of skin test reactivity to environmental allergens in healthy cats and cats with atopic dermatitis.

Science.gov (United States)

Schleifer, Sebastian G; Willemse, Ton

2003-06-01

To evaluate skin test reactivity to environmental allergens in healthy cats and in cats with atopic dermatitis (AD). 10 healthy cats and 10 cats with AD. 10 allergens in serial dilutions were injected ID on the lateral aspect of the thorax of sedated cats. Histamine (0.01% solution) and buffer solutions were used as positive and negative controls, respectively. Immediately after the last injection, 10% fluorescein solution was administered IV. Skin test results were evaluated with ultraviolet light after 15 to 30 minutes and at 4 and 6 hours by 2 independent observers. In the control group, skin tests were repeated after 6 weeks. Skin test reactivity and the nature of the immunoglobulin involved were investigated by use of the Prausnitz-Küstner test with untreated and heat-treated cat sera. Intertest and interobserver agreement were high when measurement of the diameter of the fluorescent wheal was used to evaluate skin test responses, compared with assessment of its intensity. In both groups of cats, immediate skin test reactivity was observed as an IgE-mediated reaction, as an IgG-mediated reaction, and as a result of nonspecific mast cell degranulation. There was no correlation between allergen concentration and the type of reaction observed. Skin test reactivity in cats should be evaluated after IV administration of 10% fluorescein solution by means of a Prausnitz-Küstner test to differentiate among IgE-mediated, IgG-mediated, and nonspecific reactions.

A synthetic peptide blocking TRPV1 activation inhibits UV-induced skin responses.

Science.gov (United States)

Kang, So Min; Han, Sangbum; Oh, Jang-Hee; Lee, Young Mee; Park, Chi-Hyun; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

2017-10-01

Transient receptor potential type 1 (TRPV1) can be activated by ultraviolet (UV) irradiation, and mediates UV-induced matrix metalloproteinase (MMP)-1 and proinflammatory cytokines in keratinocytes. Various chemicals and compounds targeting TRPV1 activation have been developed, but are not in clinical use mostly due to their safety issues. We aimed to develop a novel TRPV1-targeting peptide to inhibit UV-induced responses in human skin. We designed and generated a novel TRPV1 inhibitory peptide (TIP) which mimics the specific site in TRPV1 (aa 701-709: Gln-Arg-Ala-Ile-Thr-Ile-Leu-Asp-Thr, QRAITILDT), Thr 705 , and tested its efficacy of blocking UV-induced responses in HaCaT, mouse, and human skin. TIP effectively inhibited capsaicin-induced calcium influx and TRPV1 activation. Treatment of HaCaT with TIP prevented UV-induced increases of MMP-1 and pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor-α. In mouse skin in vivo, TIP inhibited UV-induced skin thickening and prevented UV-induced expression of MMP-13 and MMP-9. Moreover, TIP attenuated UV-induced erythema and the expression of MMP-1, MMP-2, IL-6, and IL-8 in human skin in vivo. The novel synthetic peptide targeting TRPV1 can ameliorate UV-induced skin responses in vitro and in vivo, providing a promising therapeutic approach against UV-induced inflammation and photoaging. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Evaluation of sex-related changes in skin topography and structure using innovative skin testing equipment.

Science.gov (United States)

Dąbrowska, M; Mielcarek, A; Nowak, I

2018-04-29

Evaluation of skin condition on the basis of parametrization and objective measurements of the parameters has become obligatory. The aim of this study was to assess sex-related changes in skin topography and structure using the skin testing equipment. The study was carried out on the group of 40 volunteers (20 females and 20 males) of the mean age 24 ± 3 years. The skin parameters were measured using 3 devices: Visioscan ®  VC 98 (skin topography), Visioline ® VL 650 (skin macro relief) and Ultrascan UC22 (ultrasound imaging of the skin). All measurements were performed on the inner part of the left forearm. The skin parameters measured revealed significant differences in skin surface and structure between females and males. The skin of all women subjects was more homogenous in its structure with the presence of more abundant superficial skin lines and wrinkles in comparison to male skin. The higher number of skin furrows in the skin of women is in agreement with literature reports claiming that men's skin has lower number of wrinkles which are deeper and more pronounced. Ultrasound imaging of the skin indicated greater thickness and lower density of the dermis of men subjects compared to those of females. Non-invasive methods of skin testing using new and advanced equipment have provided a possibility of objective parametrization and evaluation of sex-related changes in skin topography and structure. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The radiation response of skin in young and old rats

International Nuclear Information System (INIS)

Hamlet, R.; Hopewell, J.W.

1982-01-01

The results of this investigation clearly demonstrate the different radiation skin response in rats of differing ages. The reasons for these differences cannot be clarified until cell kinetic studies have been completed. These results obtained for rodent skin would appear to be in disagreement with the available data for human skin (Rubin and Casarett 1968) where no marked age-related changes were reported. Also, in pig skin studies (Hopewell and Young 1982) there was no evidence of an age effect in the dermal vascular response in 3-12-month-old animals. This may be related to the different tissue being investigated or it may reflect important species differences. Whatever the reasons behind these observations, the different skin response to radiation in rats of 7, 14 and 52 weeks of age has clearly been demonstrated and should be borne in mind when extrapolating data with rodent skin to the clinical situation. (author)

A Preliminary Test for Skin Gas Assessment Using a Porphyrin Based Evanescent Wave Optical Fiber Sensor

Directory of Open Access Journals (Sweden)

Roman SELYANCHYN

2011-02-01

Full Text Available An evanescent-wave optical fibre sensor modified with tetrakis-(4-sulfophenyl porphine (TSPP and poly(allylamine hydrochloride (PAH bilayers using layer-by-layer (LbL electrostatic self-assembly was tested to measure the gas emitted from human skin. Optical intensity changes at different wavelengths in the transmission spectrum of the porphyrin-based film were induced by the human skin gas and measured as sensor response. Influence of relative humidity, which can be a major interference to sensor response, was thoroughly studied and shown to be significantly different when compared to the influence of skin emanations. Responses of the current optical sensor system could be considered as composite sensor array, where different optical wavelengths act as channels that have selective response to specific volatile compounds. Data obtained from the sensor system was analyzed using principal component analysis (PCA. This approach enabled to distinguish skin odors of different people and their altered physiological conditions after alcohol consumption.

Penicillin skin testing in the evaluation and management of penicillin allergy.

Science.gov (United States)

Fox, Stephanie; Park, Miguel A

2011-01-01

to review the role of penicillin skin testing in the evaluation and management of penicillin allergy mediated by IgE. PubMed and OVID search of English-language articles regarding penicillin allergy, penicillin allergy testing, and management of penicillin allergy. articles pertinent to the subject matter were selected and reviewed. the major determinant (benzylpenicillin polylysine) detects the greatest number of penicillin allergic patients during skin testing, and the minor determinants of penicillin increase the sensitivity of penicillin skin testing. Penicillin skin testing to the major and minor determinants was found to have a negative predictive value of 97% to 99%. The incidence of systemic adverse reaction to penicillin skin testing is less than 1%. a detailed history of the prior reaction to penicillin is an integral part of the evaluation, but it is not accurate in predicting a positive penicillin skin test result. A patient with a negative penicillin skin test result to the major and minor determinants is at a low risk of an immediate-type hypersensitivity reaction to penicillin. Patients with a positive skin test result should undergo desensitization to penicillin or an alternative antibiotic should be considered.

Intraoperative anaphylaxis to sugammadex and a protocol for intradermal skin testing.

Science.gov (United States)

Sadleir, P H M; Russell, T; Clarke, R C; Maycock, E; Platt, P R

2014-01-01

Sugammadex is a selective binding agent for aminosteroid neuromuscular blockers whose use is increasing in anaesthetic practice. We present three cases of severe anaphylaxis coincident with sugammadex administration. Subsequent intradermal testing confirmed sugammadex as the triggering agent, with all patients having positive skin responses to a 1:100 dilution of the standard 100 mg/ml solution and two out of three having a positive response to a 1:1000 dilution. As all patients were administered sugammadex to reverse neuromuscular blockade with rocuronium, we considered that sugammadex-rocuronium complexes were a potential unique allergen. In the two patients who were additionally tested with a rocuronium-sugammadex (3.6:1 molecular ratio) mixture, the wheal-and-flare response was significantly attenuated.

Further development of LLNA:DAE method as stand-alone skin-sensitization testing method and applied for evaluation of relative skin-sensitizing potency between chemicals.

Science.gov (United States)

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

2015-04-01

To date, there has been no well-established local lymph node assay (LLNA) that includes an elicitation phase. Therefore, we developed a modified local lymph node assay with an elicitation phase (LLNA:DAE) to discriminate true skin sensitizers from chemicals that gave borderline positive results and previously reported this assay. To develop the LLNA:DAE method as a useful stand-alone testing method, we investigated the complete procedure for the LLNA:DAE method using hexyl cinnamic aldehyde (HCA), isoeugenol, and 2,4-dinitrochlorobenzene (DNCB) as test compounds. We defined the LLNA:DAE procedure as follows: in the dose-finding test, four concentrations of chemical applied to dorsum of the right ear on days 1, 2, and 3 and dorsum of both ears on day 10. Ear thickness and skin irritation score were measured on days 1, 3, 5, 10, and 12. Local lymph nodes were excised and weighed on day 12. The test dose for the primary LLNA:DAE study was selected as the dose that gave the highest left ear lymph node weight in the dose-finding study, or the lowest dose that produced a left ear lymph node of over 4 mg. This procedure was validated using nine different chemicals. Furthermore, qualitative relationship was observed between the degree of elicitation response in the left ear lymph node and the skin sensitizing potency of 32 chemicals tested in this study and the previous study. These results indicated that LLNA:DAE method was as first LLNA method that was able to evaluate the skin sensitizing potential and potency in elicitation response.

Cutaneous Leishmaniasis Induces a Transmissible Dysbiotic Skin Microbiota that Promotes Skin Inflammation.

Science.gov (United States)

Gimblet, Ciara; Meisel, Jacquelyn S; Loesche, Michael A; Cole, Stephen D; Horwinski, Joseph; Novais, Fernanda O; Misic, Ana M; Bradley, Charles W; Beiting, Daniel P; Rankin, Shelley C; Carvalho, Lucas P; Carvalho, Edgar M; Scott, Phillip; Grice, Elizabeth A

2017-07-12

Skin microbiota can impact allergic and autoimmune responses, wound healing, and anti-microbial defense. We investigated the role of skin microbiota in cutaneous leishmaniasis and found that human patients infected with Leishmania braziliensis develop dysbiotic skin microbiota, characterized by increases in the abundance of Staphylococcus and/or Streptococcus. Mice infected with L. major exhibit similar changes depending upon disease severity. Importantly, this dysbiosis is not limited to the lesion site, but is transmissible to normal skin distant from the infection site and to skin from co-housed naive mice. This observation allowed us to test whether a pre-existing dysbiotic skin microbiota influences disease, and we found that challenging dysbiotic naive mice with L. major or testing for contact hypersensitivity results in exacerbated skin inflammatory responses. These findings demonstrate that a dysbiotic skin microbiota is not only a consequence of tissue stress, but also enhances inflammation, which has implications for many inflammatory cutaneous diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Flu Vaccine Skin Patch Tested

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... Subscribe September 2017 Print this issue Health Capsule Flu Vaccine Skin Patch Tested En español Send us ... Each year, millions of people nationwide catch the flu. The best way to protect yourself is to ...

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

Science.gov (United States)

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

Skin prick test in patients with chronic allergic skin disorders

Directory of Open Access Journals (Sweden)

Pooja Bains

2015-01-01

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

Menstrual cycle and skin reactivity

DEFF Research Database (Denmark)

Agner, T; Damm, P; Skouby, S O

1991-01-01

The hypothesis was tested that a cyclic variation exists in skin reactivity to irritant stimuli. Twenty-nine healthy women with regular menstrual cycles were challenged with sodium lauryl sulfate as an irritant patch test at day 1 and at days 9 through 11 of the menstrual cycle. The skin response...... to the applied irritant stimulus was evaluated by visual scoring and also quantified by measurements of transepidermal water loss, edema formation, and blood flow in the skin. The skin response to challenge with sodium lauryl sulfate was found to be significantly stronger at day 1 than at days 9 through 11...

Does transcutaneous nerve stimulation have effect on sympathetic skin response?

Science.gov (United States)

Okuyucu, E Esra; Turhanoğlu, Ayşe Dicle; Guntel, Murat; Yılmazer, Serkan; Savaş, Nazan; Mansuroğlu, Ayhan

2018-01-01

This study examined the effects of transcutaneous electrical nerve stimulation (TENS) on the sympathetic nerve system by sympathetic skin response test. Fifty-five healthy volunteers received either: (i) 30minutes TENS (25 participants) (ii) 30minutes sham TENS (30 participants) and SSR test was performed pre- and post-TENS. The mean values of latency and peak-to-peak amplitude of five consecutive SSRs were calculated. A significant amplitude difference was found between TENS and sham TENS group both in right and left hand (p=0.04, p=0.01, respectively). However there was no significant latancy difference between two groups (p>0.05 ). TENS has an inhibitory effect on elicited SNS responses when compared with sham TENS control group. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nickel deposited on the skin-visualization by DMG test.

Science.gov (United States)

Julander, Anneli; Skare, Lizbet; Vahter, Marie; Lidén, Carola

2011-03-01

Nickel is the most common cause of contact allergy and an important risk factor for hand eczema. Visualization techniques may be powerful in showing exposures. The dimethylglyoxime (DMG) test might be used to establish skin exposure to nickel. To develop and evaluate methods for visualization of nickel on the skin by the DMG test and hand imprints. Nickel solutions at different concentrations were applied in duplicate on the hands in healthy subjects (n = 5). The DMG test and acid wipe sampling for quantification were then performed. Hand imprints were taken after manipulation of nickel-releasing tools (n = 1), and in workers performing their normal tasks (n = 7). The imprints were developed by the DMG test. The DMG test on hands gave positive results in all subjects. The lowest concentration giving rise to a colour change was set to 0.13 µg/cm(2) for DMG testing on skin. DMG test-developed imprints worked well except when hands were heavily contaminated by other particles/dust. The DMG test may be used as a simple and powerful tool for visualization of nickel on skin. DMG test-developed hand imprints may, in the future, be used for semi-quantitative or quantitative exposure assessment. © 2011 John Wiley & Sons A/S.

Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate.

Science.gov (United States)

De Jongh, Cindy M; Verberk, Maarten M; Withagen, Carien E T; Jacobs, John J L; Rustemeyer, Thomas; Kezic, Sanja

2006-06-01

Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

Skin test of radiosensitivity. Application to Fanconi anemia

International Nuclear Information System (INIS)

Dutreix, J.; Gluckman, E.

1983-01-01

A test of skin radiosensitivity is described. It is achieved by irradiating small skin fields (15 mm in diameter) with 50 kV X-rays. The radiosensitivity is evaluated from the skin reaction observed for a single acute dose of 8 and 10 Gy; it is considered increased if the reaction for 10 Gy exceeds the desquamation threshold, and scored according to the observed reaction. The test includes an evaluation of the cellular repair, assessed on the comparison of the reactions for single dose and split irradiation. The time of the reaction peak is also reported. Abnormal reactions have been observed on 4 out of 8 patients with Fanconi Anemia

Skin test of radiosensitivity. Application to Fanconi anemia

Energy Technology Data Exchange (ETDEWEB)

Dutreix, J. (Institut Gustave-Roussy, 94 - Villejuif (France)); Gluckman, E. (Centre Hayem, Hopital St.-Louis, 75 Paris (France))

1983-01-01

A test of skin radiosensitivity is described. It is achieved by irradiating small skin fields (15 mm in diameter) with 50 kV X-rays. The radiosensitivity is evaluated from the skin reaction observed for a single acute dose of 8 and 10 Gy; it is considered increased if the reaction for 10 Gy exceeds the desquamation threshold, and scored according to the observed reaction. The test includes an evaluation of the cellular repair, assessed on the comparison of the reactions for single dose and split irradiation. The time of the reaction peak is also reported. Abnormal reactions have been observed on 4 out of 8 patients with Fanconi Anemia.

Feasibility, Benefits, and Limitations of a Penicillin Allergy Skin Testing Service.

Science.gov (United States)

Narayanan, Prasanna P; Jeffres, Meghan N

2017-06-01

To critically examine the feasibility, benefits, and limitations of an inpatient penicillin skin testing service and how pharmacists can be utilized. A PubMed search was performed from July 2016 through September 2016 using the following search terms: penicillin skin testing, penicillin allergy, β-lactam allergy. Additional references were identified from a review of literature citations. All English-language studies assessing the use of penicillin skin testing as well as management and clinical outcomes of patients with a β-lactam allergy were evaluated. The prevalence of people self-identifying as penicillin allergic ranges from 10% to 20% in the United States. Being improperly labeled as penicillin allergic is associated with higher health care costs, worse clinical outcomes, and an increased prevalence of multidrug-resistant infections. Penicillin skin testing can be a tool used to clarify penicillin allergies and has been demonstrated to be a successful addition to antimicrobial stewardship programs in multiple health care settings. Prior to implementing a penicillin skin testing service, institutions will need to perform a feasibility analysis of who will supply labor and accept the financial burden as well as identify if the positive benefits of a penicillin skin testing service overcome the limitations of this diagnostic test. We conclude that institutions with high percentages of patients receiving non-β-lactams because of penicillin allergy labels would likely benefit the most from a penicillin skin testing service.

Alternative methods for skin irritation testing: the current status : ECVAM skin irritation task force report 1

NARCIS (Netherlands)

Botham, P.A.; Earl, L.K.; Fentem, J.H.; Roguet, R.; Sandt, J.J.M.

1998-01-01

The ECVAM Skin Irritation Task Force was established in November 1996, primarily to prepare a report on the current status of the development and validation of alternative tests for skin irritation and corrosion and, in particular, to identify any appropriate non-animal tests for predicting human

Inflammatory Murine Skin Responses to UV-B Light Are Partially Dependent on Endothelin-1 and Mast Cells

OpenAIRE

Metz, Martin; Lammel, Verena; Gibbs, Bernhard F.; Maurer, Marcus

2006-01-01

Endothelin (ET-1) has been shown to crucially contribute to UV-induced skin responses such as tanning. To test whether ET-1 is also involved in early cutaneous reactions to UV, we assessed ET-1 skin levels in UV-irradiated mice. In correlation with the levels of UV-induced skin inflammation, ET-1 concentrations increased substantially and continually. Moreover, blocking of ET-1 receptors (ETA) resulted in significantly decreased cutaneous inflammation following UV irradiation. When we assesse...

Immediate hypersensitivity to iodinated contrast media: diagnostic accuracy of skin tests and intravenous provocation test with low dose.

Science.gov (United States)

Sesé, L; Gaouar, H; Autegarden, J-E; Alari, A; Amsler, E; Vial-Dupuy, A; Pecquet, C; Francès, C; Soria, A

2016-03-01

The diagnosis of HSR to iodinated contrast media (ICM) is challenging based on clinical history and skin tests. This study evaluates the negative predictive value (NPV) of skin tests and intravenous provocation test (IPT) with low-dose ICM in patients with suspected immediate hypersensitivity reaction (HSR) to ICM. Thirty-seven patients with suspected immediate hypersensitivity reaction to ICM were included retrospectively. Skin tests and a single-blind placebo-controlled intravenous provocation test (IPT) with low-dose iodinated contrast media (ICM) were performed. Skin tests with ICM were positive in five cases (one skin prick test and five intradermal test). Thirty-six patients were challenged successfully by IPT, and only one patient had a positive challenge result, with a grade I reaction by the Ring and Messmer classification. Ten of 23 patients followed up by telephone were re-exposed to a negative tested ICM during radiologic examination; two experienced a grade I immediate reaction. For immediate hypersensitivity reaction to ICM, the NPV for skin tests and IPT with low dose was 80% (95% CI 44-97%). © 2016 John Wiley & Sons Ltd.

An evaluation of the diagnostic value of different skin tests with egg in clinically egg-allergic children having atopic dermatitis

DEFF Research Database (Denmark)

Hansen, Tine K; Høst, Arne; Bindslev-Jensen, Carsten

2004-01-01

Skin testing is a common diagnostic procedure in food allergy, but the final diagnosis of food allergy is based on the clinical response to food challenge. We studied the value of the skin prick-prick test (SPT), skin application food test (SAFT) and atopy patch test (APT) with fresh egg extract......-allergic children were positive in SPT and 40-60% in APT. In APT and in SPT false-positive reactions to egg were observed. In this study comprising a small number of patients including control subjects, neither SAFT nor APT with fresh whole egg extract were able to increase the diagnostic accuracy in detecting egg...

Dose-response relationships and threshold levels in skin and respiratory allergy

NARCIS (Netherlands)

Arts, J.H.E.; Mommers, C.; Heer, C.de

2006-01-01

A literature study was performed to evaluate dose-response relationships and no-effect levels for sensitization and elicitation in skin- and respiratory allergy. With respect to the skin, dose-response relationships and no-effect levels were found for both intradermal and topical induction, as well

[Diagnostic capacity of skin prick test in egg and cow's milk allergic infants].

Science.gov (United States)

Yan, Jun-mei; Chen, Jing; Li, Hai-qi; Hu, Yan

2011-05-01

Mean diameter is the most common used parameter for wheal response assessment after skin prick test. This study aimed to investigate the diagnostic capacity of mean diameter according to the outcome of oral food challenge, and to determine the cut-off points that could render food challenges unnecessary. Data of 173 children referred to the Division of Primary Child Health Care for the evaluation of suspected food allergy were prospectively studied. All children underwent skin prick test and open food challenge to the relevant food(s) in clinic. The mean wheal diameter of skin prick test was measured, and open food challenge was performed to confirm food allergy. The SPSS software package version 13.0 for windows (SPSS, Chicago, IL, USA) was used for all statistical analysis. Open food challenge was taken as the gold standard for diagnosis. Diagnostic capacity of skin prick test, including the sensitivity, specificity, positive predictive value, negative predictive value, was calculated by cross-table. In addition, receiver operating characteristic curve (ROC) was plotted and area under the curve (AUC) was calculated to quantify the accuracy of the parameter. For the 173 children, 271 open food challenges were performed with egg white, egg yolk and cow's milk, In which 123 were positive, 99 children were diagnosed as food allergy. Cutaneous symptoms (87.0%) were most common, followed by gastrointestinal symptoms (9.8%). The AUC of mean diameter was 0.794 for egg white, 0.804 for egg yolk and 0.904 for cow's milk. The sensitivity of skin prick test with a cut-off value of ≥ 3 mm was ranged from 71% to 87%, while the specificity was between 31% and 57%. The authors also defined food specific skin prick test mean diameters that were 100% diagnostic for allergy to egg white (≥ 8.5 mm), egg yolk (≥ 5.5 mm), cow's milk (≥ 5.5 mm). Predictive decision points for a positive outcome of food challenges can be calculated for egg and cow's milk using mean diameter. It

[Assessment of hypersensitivity to honey-bee venom in beekeepers by skin tests].

Science.gov (United States)

Becerril-Ángeles, Martín; Núñez-Velázquez, Marco; Marín-Martínez, Javier

2013-01-01

Beekeepers are exposed to frequent honey-bee stings, and have the risk to develop hypersensitivity to bee venom, but long-term exposure can induce immune tolerance in them. Up to 30% of beekeepers show positive skin tests with honey-bee venom. The prevalence of systemic reactions to bee stings in beekeepers is from 14% to 42%. To know the prevalence of hypersensitivity to honeybee venom in Mexican beekeepers and non-beekeepers by the use of skin tests. A group of 139 beekeepers and a group of 60 non-beekeeper volunteers had a history and physical related to age, sex, family and personal atopic history and time of exposure to bee stings. Both groups received intradermal skin tests with honey-bee venom, 0.1 mcg/mL and 1 mcg/mL, and histamine sulphate 0.1 mg/mL and Evans solution as controls. The skin tests results of both groups were compared by chi-squared test. Of the group of beekeepers, 116 were men (83%) and 23 women, average age was 39.3 years, had atopic family history 28% and personal atopy 13%, average time of exposure to bee stings was 10.9 years, skin tests with honey-bee venom were positive in 16.5% and 11% at 1 mcg/mL and 0.1 mcg/mL, respectively. In the non-beekeepers group venom skin tests were positive in 13.3% and 6.7% at 1 mcg/mL and 0.1 mcg/mL. We did not find significant differences between the two venom concentrations tested in both groups, neither in the number of positive skin tests between the two groups. We found hypersensivity to honey-bee venom slightly higher in the beekeepers than in the group apparently not exposed. Both honey-bee venom concentrations used did not show difference in the results of the skin tests. The similarity of skin tests positivity between both groups could be explained by immune tolerance due to continued exposure of beekeepers.

Oral warfarin intake affects skin inflammatory cytokine responses in rats.

Science.gov (United States)

Aleksandrov, Aleksandra Popov; Mirkov, Ivana; Zolotarevski, Lidija; Ninkov, Marina; Mileusnic, Dina; Kataranovski, Dragan; Kataranovski, Milena

2017-09-01

Warfarin is an anticoagulant used in prevention/prophylaxis of thromboembolism. Besides the effects on coagulation, non-hemorrhagic reactions have also been documented. Although cutaneous reactions were reported in some patients, the impact on skin immunity was not explored. In the present paper, the effect of 30-day oral warfarin intake on skin cytokine responses in rats was analyzed. Increased release of inflammatory cytokines (TNF, IL-1β and IL-10) was noted by skin explants from rats which received warfarin, but without effect on IL-6. No impact on epidermal cell cytokine secretion was seen, except a tendency of an increase of IL-6 response to stimulation with microbial product lipopolysaccharide (LPS). Topical application of contact allergen dinitrochlorobenzene (DNCB) resulted in slight (numerical solely) increase of TNF release by skin explants of warfarin-treated animals, while epidermal cells responded by increased secretion of all four cytokines examined. The data presented provide new information on the potential of oral warfarin to modulate skin innate immune activity. Copyright © 2017 Elsevier B.V. All rights reserved.

Media Research with a Galvanic Skin Response Biosensor: Some Kids Work Up a Sweat!

Science.gov (United States)

Clariana, Roy B.

This study considers the galvanic skin response (GSR) of sixth-grade students (n=20) using print, video, and microcomputer segments. Subjects received all three media treatments, in randomized order. Data for analysis consisted of standardized test scores and GSR measures; a moderate positive relationship was shown between cumulative GSR and…

Comparison of two interferon-gamma assays and tuberculin skin test for tracing tuberculosis contacts

NARCIS (Netherlands)

Arend, Sandra M.; Thijsen, Steven F. T.; Leyten, Eliane M. S.; Bouwman, John J. M.; Franken, Willeke P. J.; Koster, Ben F. P. J.; Cobelens, Frank G. J.; van Houte, Arend-Jan; Bossink, Ailko W. J.

2007-01-01

The tuberculin skin test (TST) has low specificity. QuantiFERON-TB Gold (QFT-G) and T-SPOT.TB are based on interferon (IFN)-gamma responses to Mycobacterium tuberculosis-specific antigens. A novel in-tube format of QFT-G (QFT-GIT) offers logistical advantages. To compare TST, QFT-GIT, and T-SPOT.TB

Association between parasitic infections and tuberculin skin test results in refugees.

Science.gov (United States)

Watts, Nathaniel S; Mizinduko, Mucho M; Barnett, Elizabeth D; White, Laura F; Hochberg, Natasha S

Parasitic infections are known to modulate the immune response necessary for controlling Mycobacterium tuberculosis infection. We sought to investigate species-specific effects of parasite infection on M. tuberculosis infection. As part of the Refugee Health Assessment Program, stool examinations and tuberculin skin testing were performed on refugees seen at Boston Medical Center between 1995 and 2012. Tuberculin skin test (TST) and stool examination data were collected for 6669 refugees; 3349 (50.2%) were TST positive (≥10 mm). Among TST-positive subjects, 176 (5.3%) had helminth infections and 1149 (34.3%) protozoa. After adjusting for sex, age, and country of origin, helminth and protozoan infections were not associated with TST-positivity. When species-specific effects were examined, subjects infected with Trichuris trichiura and Giardia lamblia had reduced odds of TST-positivity (adjusted OR [aOR] 0.65 [95%CI 0.44-0.96; p = 0.03] and aOR 0.79 [95%CI 0.65-0.95, p = 0.01], respectively). Our findings suggest that T. trichiura and G. lamblia may provide protection against M. tuberculosis infection. This study adds to a growing body of literature suggesting that immune response modulation and susceptibility to M. tuberculosis infection is parasite species-dependent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Utility of minor determinants for skin testing in inpatient penicillin allergy evaluation.

Science.gov (United States)

Geng, Bob; Eastman, Jacqueline J; Mori, Karen; Braskett, Melinda; Riedl, Marc A

2017-09-01

Most patients with a history of penicillin allergy can tolerate penicillin. Skin testing can identify tolerant patients, but not all known allergenic determinants are commercially available. Protocols exist that use only available reagents, but the sensitivity and safety of these protocols, particularly for hospitalized patients, are controversial. To determine the number of hospitalized patients referred for penicillin skin testing who showed unique positivity to the minor determinants penicilloate and penilloate. A retrospective chart review was conducted of all inpatients who underwent penicillin skin testing at 1 institution. Patients were referred by their treating physician. All patients underwent skin prick testing to benzylpenicilloyl polylysine (major determinant), penicillin G, penicilloate, penilloate (minor determinants), amoxicillin, and positive and negative controls. If the result was negative, then intradermal testing was done with the same penicillin determinants and the negative control. A 4-mm wheal with flare was considered a positive reaction. Inpatient penicillin skin testing was done in 528 subjects. Any positive test reaction was found in 107 subjects (20%). Three subjects (3%) reacted to penilloate only, 25 (23%) reacted to penicilloate only, 2 (2%) reacted to penicillin G only, and 8 (8%) reacted to amoxicillin only. Sixty-eight subjects (64%) reacted to a compound other than the major determinant. This study found a high rate of exclusively positive skin test reactions to the minor determinants penicilloate and penilloate. Because patients with positive test reactions are at increased risk of reaction to drug challenge, these data support the use of these reagents for penicillin skin testing in hospitalized patients. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Fractionated laser resurfacing corrects the inappropriate UVB response in geriatric skin.

Science.gov (United States)

Spandau, Dan F; Lewis, Davina A; Somani, Ally-Khan; Travers, Jeffrey B

2012-06-01

Non-melanoma skin cancer is a disease primarily afflicting geriatric patients as evidenced by the fact that 80% of all non-melanoma skin cancers are diagnosed in patients over the age of 60 years. As such, geriatric skin responds to cancer-inducing UVB irradiation in a manner that allows the establishment of tumor cells. Currently, the only effective treatment for non-melanoma skin cancer is the removal of the tumors after they appear, indicating the need for a more cost-effective prophylactic therapy. Geriatric volunteers were treated with fractionated laser resurfacing therapy on either sun-protected (upper buttocks) or chronically sun-exposed (dorsal forearm) skin. Fractionated laser resurfacing therapy was shown to decrease the occurrence of senescent fibroblasts in geriatric dermis, increase the dermal expression of IGF-1, and correct the inappropriate UVB response observed in untreated geriatric skin. These responses to fractionated laser resurfacing were equal to the effects seen previously using the more aggressive wounding following dermabrasion. Furthermore, fractionated laser resurfacing was equally effective in both sun-protected and sun-exposed skin. The ability of fractionated laser resurfacing treatment to protect against the occurrence of UVB-damaged proliferating keratinocytes indicates the potential of fractionated laser resurfacing to reduce or prevent aging-associated non-melanoma skin cancer.

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

Science.gov (United States)

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.

The role of variants from the innate immune system genes in tuberculosis and skin test response in a Native American population.

Science.gov (United States)

Lindenau, Juliana D; Salzano, Francisco M; Hurtado, Ana M; Hill, Kim R; Hutz, Mara H

2016-10-01

Native American populations show higher tuberculosis (TB) mortality and infectivity rates than non-Native populations. Variants in the innate immune system seem to have an important role on TB susceptibility. The role of some innate immune system variants in TB susceptibility and/or skin test response (PPD) were investigated in the Aché, a Native American population. Complement receptor 1 and toll like receptor 9 variants were associated with anergy to PPD and protection to TB, respectively. These findings demonstrate an important role of the innate immune system variants in TB susceptibility. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

The skin prick test – European standards

Directory of Open Access Journals (Sweden)

Heinzerling Lucie

2013-02-01

Full Text Available Abstract 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.

Papain-induced asthma: diagnosis by skin test, RAST and bronchial provocation test

International Nuclear Information System (INIS)

Baur, X.; Fruhmann, G.

1979-01-01

Seven out of eleven workers occupationally exposed to airborne papain developed immediate hypersensitive reactions, predominantly asthma and rhinitis. Skin tests and RAST with papain were positive in all symptomatic workers, but not in the four asymptomatic workers. Furthermore, out of forty non-exposed asthmatics, thirty-eight had negative RAST results and all had negative skin test results. Bronchial provocation tests with 0.15-0.5 mg papain performed in five patients with a positive case history showed in each case an immediate asthmatic reaction; in addition to that, one patient developed signs of a dual asthmatic reaction. These results suggest that airborne papain is a highly immunogenic agent in humans, which induces type I allergic reactions in a large percentage of the exposed subjects. (author)

Opisthorchis felineus negatively associates with skin test reactivity in Russia-EuroPrevall-International Cooperation study.

Science.gov (United States)

Fedorova, O S; Janse, J J; Ogorodova, L M; Fedotova, M M; Achterberg, R A; Verweij, J J; Fernández-Rivas, M; Versteeg, S A; Potts, J; Minelli, C; van Ree, R; Burney, P; Yazdanbakhsh, M

2017-07-01

Most studies on the relationship between helminth infections and atopic disorders have been conducted in (sub)tropical developing countries where exposure to multiple parasites and lifestyle can confound the relationship. We aimed to study the relationship between infection with the fish-borne helminth Opishorchis felineus and specific IgE, skin prick testing, and atopic symptoms in Western Siberia, with lifestyle and hygiene standards of a developed country. Schoolchildren aged 7-11 years were sampled from one urban and two rural regions. Skin prick tests (SPT) and specific IgE (sIgE) against food and aeroallergens were measured, and data on allergic symptoms and on demographic and socioeconomic factors were collected by questionnaire. Diagnosis of opisthorchiasis was based on PCR performed on stool samples. Of the 732 children included, 34.9% had opisthorchiasis. The sensitization to any allergen when estimated by positive SPT was 12.8%, while much higher, 24.0%, when measured by sIgE. Atopic symptoms in the past year (flexural eczema and/or rhinoconjunctivitis) were reported in 12.4% of the children. SPT was positively related to flexural eczema and rhinoconjunctivitis, but not to wheezing. Opisthorchiasis showed association with lower SPT response, as well as borderline association with low IgE reactivity to any allergen. However, the effect of opisthorchiasis on SPT response was not mediated by IgE, suggesting that opisthorchiasis influences SPT response through another mechanism. Opisthorchiasis also showed borderline association with lower atopic symptoms. There is a negative association between a chronic helminth infection and skin prick test reactivity even in a developed country. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Documented tuberculin skin testing among infliximab users following a multi-modal risk communication interventions.

Science.gov (United States)

Shatin, Deborah; Rawson, Nigel S B; Curtis, Jeffrey R; Braun, M Miles; Martin, Carolyn K; Moreland, Larry W; Becker, Angela F; Patkar, Nivedita M; Allison, Jeroan J; Saag, Kenneth G

2006-01-01

Following its licensure, tuberculosis (TB) was reported as a potential adverse effect of infliximab. Subsequently, the product circular was changed to recommend tuberculin skin testing before patients received infliximab, which was reinforced by several risk communication efforts. The aim of this study was to evaluate patterns and predictors of documented tuberculin skin testing in patients before and after manufacturer, federal, and academic risk communications. Patients administered infliximab were identified from 11 health plans located throughout the United States, and claims data were examined to determine whether the patients had received a tuberculin skin test. Patients were divided into three cohorts depending on the timing of their first infliximab treatment in relation to the risk communication efforts. The overall tuberculin skin testing rate doubled from 15.4% in the first cohort to 30.9% in the last cohort, while the rate of pre-infliximab treatment testing increased from 0 to 27.7% (Chi-squared test for trend, p skin testing rates were significantly higher in women, those with a diagnosis of rheumatoid or psoriatic arthritis, and those with a rheumatologist as prescriber. After multivariable analysis, only rheumatologist remained significantly associated with tuberculin skin testing. Although the tuberculin skin testing rate was relatively low overall, tuberculin skin testing doubled over 30 months of ongoing risk communication efforts and under ascertainment likely occurred. We also found variation in the tuberculin skin testing rate associated with physician specialty. This study demonstrates a significant change in patient care following risk communication efforts. (c) 2005 John Wiley & Sons, Ltd.

Skin Sensitive Difference of Human Body Sections under Clothing-Smirnov Test of Skin Surface Temperatures' Dynamic Changing

Institute of Scientific and Technical Information of China (English)

LI Jun; WU Hai-yan; WANG Yun-yi

2004-01-01

Skin sensitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design.By a new method of researching on clothing comfort perception,the skin temperature live changing procedure of human body sections affected by the same cold stimulation is inspected.Furthermore with the Smirnov test the skin temperatures dynamic changing patterns of main human body sections are obtained.

Skin Blood Perfusion and Cellular Response to Insertion of Insulin Pen Needles With Different Diameters

DEFF Research Database (Denmark)

Præstmark, Kezia Ann; Stallknecht, Bente Merete; Bo Jensen, Casper

2014-01-01

skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after...... blood perfusion recording and grouped according to needle type, skin blood perfusion response relates to needle diameter. The response was significantly higher after insertions with 28G and hooked 32G needles than with 30G (P ..., but there was a trend of an increased response with increasing needle diameter. Skin blood perfusion response to pen needle insertions rank according to needle diameter, and the tissue response caused by hooked 32G needles corresponds to that of 28G needles. The relation between needle diameter and trauma when...

Measurement of the force–displacement response of in vivo human skin under a rich set of deformations

KAUST Repository

Flynn, Cormac

2011-06-01

The non-linear, anisotropic, and viscoelastic properties of human skin vary according to location on the body, age, and individual. The measurement of skin\\'s mechanical properties is important in several fields including medicine, cosmetics, and forensics. In this study, a novel force-sensitive micro-robot applied a rich set of three-dimensional deformations to the skin surface of different areas of the arms of 20 volunteers. The force-displacement response of each area in different directions was measured. All tested areas exhibited a non-linear, viscoelastic, and anisotropic force-displacement response. There was a wide quantitative variation in the stiffness of the response. For the right anterior forearm, the ratio of the maximum probe reaction force to maximum probe displacement ranged from 0.44Nmm-1 to 1.45Nmm-1. All volunteers exhibited similar qualitative anisotropic characteristics. For the anterior right forearm, the stiffest force-displacement response was when the probe displaced along the longitudinal axis of the forearm. The response of the anterior left forearm was stiffest in a direction 20° to the longitudinal axis of the forearm. The posterior upper arm was stiffest in a direction 90° to the longitudinal axis of the arm. The averaged posterior upper arm response was less stiff than the averaged anterior forearm response. The maximum probe force at 1.3mm probe displacement was 0.69N for the posterior upper arm and 1.1N for the right anterior forearm. The average energy loss during the loading-unloading cycle ranged from 11.9% to 34.2%. This data will be very useful for studying the non-linear, anisotropic, and viscoelastic behaviour of skin and also for generating material parameters for appropriate constitutive models. © 2011 IPEM.

Full-thickness human skin explants for testing the toxicity of topically applied chemicals

International Nuclear Information System (INIS)

Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr.

1990-01-01

This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36 degrees C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components

Full-thickness human skin explants for testing the toxicity of topically applied chemicals

Energy Technology Data Exchange (ETDEWEB)

Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr. (Johns Hopkins Univ., Baltimore, MD (USA))

1990-09-01

This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36{degrees}C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components.

Penicillin skin testing is a safe and effective tool for evaluating penicillin allergy in the pediatric population.

Science.gov (United States)

Fox, Stephanie J; Park, Miguel A

2014-01-01

Penicillin skin testing has been validated in the evaluation of adult patients with penicillin allergy. However, the commercially available benzylpenicilloyl polylysine (Pre-Pen) is not indicated in the pediatric population. Moreover, the safety and validity of penicillin skin testing in the pediatric population has not been well studied. We describe the safety and validity of penicillin skin testing in the evaluation of children with a history of penicillin allergy. Children (penicillin allergy were evaluated with penicillin skin tests and were reviewed for basic demographics, penicillin skin test results, adverse drug reaction to penicillin after penicillin skin test, and adverse reaction to penicillin skin test. By using the χ(2) test, we compared the differences in the proportion of children and adults with a positive penicillin skin test. P value (penicillin skin testing; 703 of 778 patients had a negative penicillin skin test (90.4%), 66 had a positive test (8.5%), and 9 had an equivocal test (1.1%). Children were more likely to have a positive penicillin skin test (P penicillin skin test (52%) were challenged with penicillin, and 14 of 369 patients (3.8%) had an adverse drug reaction. No adverse reactions to penicillin skin testing were observed. Penicillin skin testing was safe and effective in the evaluation of children with a history of penicillin allergy. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

[Allergens used in skin tests in Mexico].

Science.gov (United States)

Larenas Linnemann, Désirée; Arias Cruz, Alfredo; Guidos Fogelbach, Guillermo Arturo; Cid del Prado, Mari Lou

2009-01-01

Immunotherapy is the only recognized causal treatment for allergies. It is prepared on an individual basis, based on the patient's clinical history and the result of the skin prick test (SPT). An adequate composition of the allergens with which to test the patient is crucial for an optimal diagnosis. To know allergens used in tests in allergy practices in Mexico. A national survey among all members of the Colegio Mexicano de Inmunología Clínica y Alergia (CMICA) and of the Colegio Mexicano de Pediatras Especialistas en Inmunología Clínica y Alergia (COMPEDIA) was carried out. In a second phase respondents were asked to send in the composition of a routine SPT in their clinic. The results are presented descriptively and the frequency is calculated by which certain allergen is tested in the interviewed practices. A survey response rate of 61 (17%) was obtained and 54% showed their SPT content. Weeds' representation in the SPT seems adequate; Atriplex is tested in all allergy practices. Some trees that show cross-reactivity might be eliminated from the SPT, but 20% doesn't test for Cynodon nor Holcus, and 25% doesn't for important allergens as cat, dog and cockroach. House dust and tobacco are still tested with certain frequency. The selection of which allergens to test in a SPT is based on multiple data, that change continuously with new investigations and discoveries. Our specialty is the most indicated--and obligated--to adjust constantly to these changes to have the best diagnostic tool to detect specific allergies.

Hypersensitivity reactions to penicillins: studies in a group of patients with negative benzylpenicillin G skin test.

Science.gov (United States)

Qiao, H-L; Li, Z; Yang, J; Tian, X; Gao, N; Jia, L-J

2009-06-01

Although skin tests are usually employed to evaluate current penicillin allergy status, a negative result does not exclude hypersensitivity. There is a need for accurate in vitro tests to exclude hypersensitivity. A radioallergosorbent test (RAST) is a potentially good supplementary approach, but there is little information on the suitability of this method to diagnose penicillin hypersensitivity in subjects with a negative skin test to benzylpenicillin. A total of 133 patients with a negative skin test to benzylpenicillin G (PG) and all of whom developed allergic reactions to PG were studied. RAST was used to detect eight kinds of specific IgE antibodies to penicillins in serum, which included four kinds of major and minor antigenic determinants to four penicillin drugs. The combination sites for the specific IgE antibodies were studied by RAST inhibition test. The rate of positive reactions for the specific IgE antibodies was 59.40% (79/133). Of the eight kinds of antigenic determinants, the positive rates for specific IgE against the major and minor determinants were 39.10% (52) and 42.86% (57) respectively. Of the four drugs, positive cases only to PG were 10 (7.5%), were significantly fewer than the cross-reacting positive cases (36) to PG (P penicillins could induce specific responses with a variable degree of cross-reactivity among the different penicillins. Radioallergosorbent test is a good complementary test in persons who are skin-test negative with PG, and the sensitivity of RAST increases with increasing specificity of IgE antibodies to be detected. 6-APA and the groups, making part of the different side-chains on penicillins, all contributed to the cross-reactivity.

Compatibility of Clinical Manifestation with Skin Prick Test Result and Food Provocation Test in Food Cross Reaction

OpenAIRE

Lubis, Azwin; Barlianto, Wisnu; Endaryanto, Anang; Harsono, Ariyanto

2017-01-01

Background: Subjective diagnostic test of food allergy is hugely biased, resulting in irrational diet avoidance. Additional objective tools by skin prick test following food provocation test resulting more accurate cause and prevalence on population. Purpose: To evaluate the compatibility of clinical symptoms with skin prick test and provocation test for imunoglobulin E (IgE) mediated food allergy in Dr. Soetomo Hospital Surabaya. Methods: Cross sectional observational analytic study. Patient...

Comparison of the skin sensitizing potential of unsaturated compounds as assessed by the murine local lymph node assay (LLNA) and the guinea pig maximization test (GPMT).

Science.gov (United States)

Kreiling, R; Hollnagel, H M; Hareng, L; Eigler, D; Lee, M S; Griem, P; Dreessen, B; Kleber, M; Albrecht, A; Garcia, C; Wendel, A

2008-06-01

The skin sensitization potential of eight unsaturated and one saturated lipid (bio)chemicals was tested in both the LLNA and the GPMT to address the hypothesis that chemicals with unsaturated carbon-carbon double bonds may result in a higher number of unspecific (false positive) results in the LLNA compared to the GPMT. Seven substances (oleic acid, linoleic acid, linolenic acid, undecylenic acid, maleic acid, squalene and octinol) gave clear positive results in the LLNA (stimulation index (SI)> or = 3) and thus would require labelling as skin sensitizer. Fumaric acid and succinic acid gave clearly negative results. In the GPMT, besides some sporadic skin reactions, reproducible skin reactions indicating an allergic response were found in a few animals for four test substances. Based on the GPMT results, only undecylenic acid would have to be classified and labelled as a skin sensitizer according to the European Dangerous Substance Directive (67/548/EEC) (results for linoleic acid were inconclusive), while the other seven test substances would not require labelling. Possible mechanisms for unspecific skin cell stimulation and lymph node responses are discussed. In conclusion, the suitability of the LLNA for unsaturated compounds bearing structural similarity to the tested substances should be carefully considered and the GPMT should remain available as an accepted test method for skin sensitization hazard identification.

Effect of skin temperature on cutaneous vasodilator response to the β-adrenergic agonist isoproterenol.

Science.gov (United States)

Hodges, Gary J; Kellogg, Dean L; Johnson, John M

2015-04-01

The vascular response to local skin cooling is dependent in part on a cold-induced translocation of α2C-receptors and an increased α-adrenoreceptor function. To discover whether β-adrenergic function might contribute, we examined whether β-receptor sensitivity to the β-agonist isoproterenol was affected by local skin temperature. In seven healthy volunteers, skin blood flow was measured from the forearm by laser-Doppler flowmetry and blood pressure was measured by finger photoplethysmography. Data were expressed as cutaneous vascular conductance (CVC; laser-Doppler flux/mean arterial blood pressure). Pharmacological agents were administered via intradermal microdialysis. We prepared four skin sites: one site was maintained at a thermoneutral temperature of 34°C (32 ± 10%CVCmax) one site was heated to 39°C (38 ± 11%CVCmax); and two sites were cooled, one to 29°C (22 ± 7%CVCmax) and the other 24°C (16 ± 4%CVCmax). After 20 min at these temperatures to allow stabilization of skin blood flow, isoproterenol was perfused in concentrations of 10, 30, 100, and 300 μM. Each concentration was perfused for 15 min. Relative to the CVC responses to isoproterenol at the thermoneutral skin temperature (34°C) (+21 ± 10%max), low skin temperatures reduced (at 29°C) (+17 ± 6%max) or abolished (at 24°C) (+1 ± 5%max) the vasodilator response, and warm (39°C) skin temperatures enhanced the vasodilator response (+40 ± 9%max) to isoproterenol. These data indicate that β-adrenergic function was influenced by local skin temperature. This finding raises the possibility that a part of the vasoconstrictor response to direct skin cooling could include reduced background β-receptor mediated vasodilation. Copyright © 2015 the American Physiological Society.

The response of mouse skin to multiple small doses of radiation

International Nuclear Information System (INIS)

Denekamp, J.; Harris, S.R.

1975-01-01

The response of mouse skin has been tested by irradiating the foot of albino mice and scoring erythema and desquamation during the following month. Multiple small doses of 150, 250 and 350 rad have been given 'daily', and the test dose necessary to achieve a given reaction has been determined one day after the last small fraction. This test dose has been compared with the single dose necessary to produce the same reaction level in previously untreated mice, in order to determine the ratio of the slopes of the dose-response curve at low and high doses: Slope ratio = (single dose - test dose)/total fractionated priming dose. In three separate experiments the slope ratio decreased as the dose per fraction was reduced from 350 to 150 rad. This conflicts with the data of Dutreix et al, who found a constant slope ratio over this dose range. The present data are compared with those obtained by Denekamp using 4, 9 and 14 fractions of 300 rad and by Douglas et al, using the same experimental technique, over the dose range 45 to 200 rad/fraction. In addition, the results from multifraction experiments in which equal dose increments were administered until the requisite skin reaction was achieved are also analysed in terms of their slope ratio (Fowler et al. Douglas et al). When all these results are plotted it is impossible to be sure whether the slope ratio is decreasing over the range 300 to 45 rad per fraction, although it seems likely. Most of the values at low doses lie in the range 0.15 to 0.25, indicating that at low doses the radiation is only 15 to 25% as effective per rad in causing cell death as at higher doses. (author)

Skin irritability to sodium lauryl sulfate is associated with increased positive patch test reactions.

Science.gov (United States)

Schwitulla, J; Brasch, J; Löffler, H; Schnuch, A; Geier, J; Uter, W

2014-07-01

As previous observations have indicated an inter-relationship between irritant and allergic skin reactions we analysed data of synchronous allergen and sodium lauryl sulfate (SLS) patch tests in terms of a relationship between SLS responsiveness and allergic patch test reactions. To analyse differences in terms of allergen-specific and overall reaction profiles between patients with vs. those without an irritant reaction to SLS. Clinical data of 26 879 patients patch tested from 2008 to 2011 by members of the Information Network of Departments of Dermatology were analysed. After descriptive analyses, including the MOAHLFA index, the positivity ratio and the reaction index, a negative binomial hurdle model was adopted to investigate the correlation between SLS reactivity and positive patch test reactions. Men, patients aged ≥ 40 years and patients with an occupational dermatitis background were over-represented in the SLS-reactive group. Patients with an irritant reaction to SLS showed a higher proportion of weak positive reactions, as well as more questionable and irritant reactions to contact allergens than patients not reactive to SLS. The risk of an additional positive patch test reaction increased by 22% for SLS-reactive patients compared with those who were SLS negative. The marked association between SLS reactivity and the number of positive reactions in patch test patients may be due to nonspecific increased skin reactivity at the moment of patch testing only. However, increased SLS reactivity could also be due to longer-lasting enhanced skin irritability, which may have promoted (poly-)sensitization. Further studies, for example with longitudinal data on patients repeatedly patch tested with SLS and contact allergens, are necessary. © 2014 British Association of Dermatologists.

Appreciating the image of God in all humanity: Towards a pastoral response to skin lightening as image enhancement to exit dark skin

Directory of Open Access Journals (Sweden)

Noah K. Tenai

2016-05-01

Full Text Available The practice of skin lightening is prevalent amongst dark-skinned people globally. Various current studies that map this practice and that seek motivations behind the practice are examined. It is observed that through shrewd marketing, dark-skinned people are offered a promise of a better quality of life, obtained by a lighter skin, through the use of skin lighteners. In spite of the severe health risks involved, the promise is ostensibly irresistible to some dark-skinned persons. A pastoral response is offered that affirms the full personhood and complete humanity of dark-skinned people as fully human and whole in their dark skins. Keywords: Skin lightening, Dark skin, Image of God

In vitro assessment of skin irritation potential of surfactant-based formulations by using a 3-D skin reconstructed tissue model and cytokine response.

Science.gov (United States)

Walters, Russel M; Gandolfi, Lisa; Mack, M Catherine; Fevola, Michael; Martin, Katharine; Hamilton, Mathew T; Hilberer, Allison; Barnes, Nicole; Wilt, Nathan; Nash, Jennifer R; Raabe, Hans A; Costin, Gertrude-Emilia

2016-12-01

The personal care industry is focused on developing safe, more efficacious, and increasingly milder products, that are routinely undergoing preclinical and clinical testing before becoming available for consumer use on skin. In vitro systems based on skin reconstructed equivalents are now established for the preclinical assessment of product irritation potential and as alternative testing methods to the classic Draize rabbit skin irritation test. We have used the 3-D EpiDerm™ model system to evaluate tissue viability and primary cytokine interleukin-1α release as a way to evaluate the potential dermal irritation of 224 non-ionic, amphoteric and/or anionic surfactant-containing formulations, or individual raw materials. As part of our testing programme, two representative benchmark materials with known clinical skin irritation potential were qualified through repeated testing, for use as references for the skin irritation evaluation of formulations containing new surfactant ingredients. We have established a correlation between the in vitro screening approach and clinical testing, and are continually expanding our database to enhance this correlation. This testing programme integrates the efforts of global manufacturers of personal care products that focus on the development of increasingly milder formulations to be applied to the skin, without the use of animal testing. 2016 FRAME.

CAT SCRATCH DISEASE: RESULTS OF COMPLEMENT-FIXATION AND SKIN TESTS

Science.gov (United States)

Serologic and skin-testing data on a group of patients having cat scratch disease are presented to demonstrate a possible relationship to the psitt...indicate that the incidence of positive serologic reactions with the psitt-LGV group antigen is consistently higher in patients with cat scratch disease...patients, 2 of 5 did not respond with positive skin reactions when tested with cat scratch antigen, and at least 2 of the remaining 3 responded in a manner difficult to interpret.

QSAR models of human data can enrich or replace LLNA testing for human skin sensitization

Science.gov (United States)

Alves, Vinicius M.; Capuzzi, Stephen J.; Muratov, Eugene; Braga, Rodolpho C.; Thornton, Thomas; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

2016-01-01

Skin sensitization is a major environmental and occupational health hazard. Although many chemicals have been evaluated in humans, there have been no efforts to model these data to date. We have compiled, curated, analyzed, and compared the available human and LLNA data. Using these data, we have developed reliable computational models and applied them for virtual screening of chemical libraries to identify putative skin sensitizers. The overall concordance between murine LLNA and human skin sensitization responses for a set of 135 unique chemicals was low (R = 28-43%), although several chemical classes had high concordance. We have succeeded to develop predictive QSAR models of all available human data with the external correct classification rate of 71%. A consensus model integrating concordant QSAR predictions and LLNA results afforded a higher CCR of 82% but at the expense of the reduced external dataset coverage (52%). We used the developed QSAR models for virtual screening of CosIng database and identified 1061 putative skin sensitizers; for seventeen of these compounds, we found published evidence of their skin sensitization effects. Models reported herein provide more accurate alternative to LLNA testing for human skin sensitization assessment across diverse chemical data. In addition, they can also be used to guide the structural optimization of toxic compounds to reduce their skin sensitization potential. PMID:28630595

Posterior superior temporal sulcus responses predict perceived pleasantness of skin stroking

Directory of Open Access Journals (Sweden)

Monika Davidovic

2016-09-01

Full Text Available Love and affection is expressed through a range of physically intimate gestures, including caresses. Recent studies suggest that posterior temporal lobe areas typically associated with visual processing of social cues also respond to interpersonal touch. Here, we asked whether these areas are selective to caress-like skin stroking. We collected functional magnetic resonance imaging (fMRI data from 23 healthy participants and compared brain responses to skin stroking and vibration. We did not find any significant differences between stroking and vibration in the posterior temporal lobe; however, right posterior superior temporal sulcus (pSTS responses predicted healthy participant's perceived pleasantness of skin stroking, but not vibration. These findings link right pSTS responses to individual variability in perceived pleasantness of caress-like tactile stimuli. We speculate that the right pSTS may play a role in the translation of tactile stimuli into positively valenced, socially relevant interpersonal touch and that this system may be affected in disorders associated with impaired attachment.

Influence of Clothing Fabrics on Skin Microcirculation

Institute of Scientific and Technical Information of China (English)

CHENG Ling; PAN Ning; ZHAO Lian-ying; HUAUNG Gu

2010-01-01

This study investigated the effects of clothing fabric on human skin microcirculation. Once skin is covered with a clothing fabric, human sensations, namely, coolness, warmth, softness, and roughness, are amused immediately, and the cutaneous micrecireulation may be changed consequently. Since the complex relationships of the human skin, the environment, and the clothing, there is few publication focusing on the physiological responses of the skin to the fabrics. In this paper, a Laser Doppler Flowmetry (LDF) was used to test the dynamic responses of the skin blood flow when the fabric was placed on the skin. Effects of different fabrics on the skin blood flux were investigated. The results show that cold stimulation of fabric has remarkable influences on the skin blood flux, and the surface properties of fabric are of importance to affect the human skin blood flow.

389 Allergic Reactions to Local Anesthetics: Detection by Skin Tests and Subcutaneous Provocation. Analysis of 160 Cases

Science.gov (United States)

Arcanjo, Luiz; Gonçalves Tavares, Tania Maria; Delcourt, Nathalia; Baroni, Juliana; Rios, João; Rios, José Luiz

2012-01-01

Background Adverse reactions to local anesthetics (LA) are frequent and often referred to as allergic. Although immune-mediated reactions are rare, it should be investigated for suspected cases. The objective of this study was to determine the frequency of positive skin test to these drugs in patients with a suspected history of allergic reactions and describe the main socio-demographic characteristics of these individuals. Methods Retrospective study of medical records of patients attended at Policlínica Geral do Rio de Janeiro Allergic Clinic, between 2008 and 2011. The parameters evaluated were the test indication and the patient ages and gender. The drug tested was that the patient had a history of suspicion. Patients underwent skin prick and intradermal tests and subcutaneous provocation. Descriptive statistical analysis of the data was performed. Results It was performed 160 tests (125 female). Three of this total was excluded due to inconclusive results. In women, the highest proportion of tests was in the age group from 41 to 60 years (43%), while in males the higher concentration was at a youngest age group: 21 to 40 years (41%). The most common indication (103 cases, 65%) for the tests was a previous suspected anaphylactic reaction by LA. Seven of 157 tests had a positive result (4.4%), 6 of them occurred in women (4.8%). Only one test resulted in a type of anaphylactic reaction response (0.67%). All patients who presented positive response to the test had a history of per-anesthetic reaction that suggested an immune-mediated mechanism. Conclusions In patients with a history of previous reaction to local anesthetics, the skin tests with these drugs have a key role in the prevention of anaphylaxis, and on guidance for adequate anesthetic procedures.

EPA Releases Draft Policy to Reduce Animal Testing for Skin Sensitization

Science.gov (United States)

The document, Draft Interim Science Policy: Use of Alternative Approaches for Skin Sensitization as a Replacement for Laboratory Animal Testing, describes the science behind the non-animal alternatives that can now be used to identify skin sensitization.

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

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Hamid Reza Kianifar

2016-05-01

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

Sporotrichin Skin Test for the Diagnosis of Sporotrichosis

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Alexandro Bonifaz

2018-05-01

Full Text Available Sporotrichosis is the most common implantation mycosis caused by several species of the Sporothrix schenckii complex. The gold standard for diagnosis is concerned with the isolation of the fungus; although, fresh examinations, staining, and biopsies are also helpful for this purpose. The sporotrichin is an antigenic complex comprised of a peptide-rhamnomannan, which is relevant with respect to pathogenic fungi; it is primarily used for serological and skin testing. We present a study regarding the use of sporotrichin as a diagnostic aid for cutaneous sporotrichosis. Furthermore, 138 cases with suspicion of sporotrichosis were included, 55 of which were proven through cultures. Moreover, out of these 55 cases, 52 (94.5% tested positive for sporotrichin, while the negative cases corresponded to the disseminated cutaneous forms. We observed a sensitivity of 94.5% and a specificity of 95.2%. We consider that the use of sporotrichin as a skin test helps us as an auxiliary diagnosis before a positive sample culture.

Sporotrichin Skin Test for the Diagnosis of Sporotrichosis.

Science.gov (United States)

Bonifaz, Alexandro; Toriello, Conchita; Araiza, Javier; Ramírez-Soto, Max C; Tirado-Sánchez, Andrés

2018-05-09

Sporotrichosis is the most common implantation mycosis caused by several species of the Sporothrix schenckii complex. The gold standard for diagnosis is concerned with the isolation of the fungus; although, fresh examinations, staining, and biopsies are also helpful for this purpose. The sporotrichin is an antigenic complex comprised of a peptide-rhamnomannan, which is relevant with respect to pathogenic fungi; it is primarily used for serological and skin testing. We present a study regarding the use of sporotrichin as a diagnostic aid for cutaneous sporotrichosis. Furthermore, 138 cases with suspicion of sporotrichosis were included, 55 of which were proven through cultures. Moreover, out of these 55 cases, 52 (94.5%) tested positive for sporotrichin, while the negative cases corresponded to the disseminated cutaneous forms. We observed a sensitivity of 94.5% and a specificity of 95.2%. We consider that the use of sporotrichin as a skin test helps us as an auxiliary diagnosis before a positive sample culture.

Thermal Response of In Vivo Human Skin to Fractional Radiofrequency Microneedle Device

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Woraphong Manuskiatti

2016-01-01

Full Text Available Background. Fractional radiofrequency microneedle system (FRMS is a novel fractional skin resurfacing system. Data on thermal response to this fractional resurfacing technique is limited. Objectives. To investigate histologic response of in vivo human skin to varying energy settings and pulse stacking of a FRMS in dark-skinned subjects. Methods. Two female volunteers who were scheduled for abdominoplasty received treatment with a FRMS with varying energy settings at 6 time periods including 3 months, 1 month, 1 week, 3 days, 1 day, and the time immediately before abdominoplasty. Biopsy specimens were analyzed using hematoxylin and eosin (H&E, Verhoeff-Van Gieson (VVG, colloidal iron, and Fontana-Masson stain. Immunohistochemical study was performed by using Heat Shock Protein 70 (HSP70 antibody and collagen III monoclonal antibody. Results. The average depth of radiofrequency thermal zone (RFTZ ranged from 100 to 300 μm, correlating with energy levels. Columns of cell necrosis and collagen denaturation followed by inflammatory response were initially demonstrated, with subsequent increasing of mucin at 1 and 3 months after treatment. Immunohistochemical study showed positive stain with HSP70. Conclusion. A single treatment with a FRMS using appropriate energy setting induces neocollagenesis. This wound healing response may serve as a mean to improve the appearance of photodamaged skin and atrophic scars.

Performance and Pain Tolerability of Current Diagnostic Allergy Skin Prick Test Devices.

Science.gov (United States)

Tversky, Jody R; Chelladurai, Yohalakshmi; McGready, John; Hamilton, Robert G

2015-01-01

Allergen skin prick testing remains an essential tool for diagnosing atopic disease and guiding treatment. Sensitivity needs to be defined for newly introduced devices. Our aim was to compare the performance of 10 current allergy skin prick test devices. Single- and multiheaded skin test devices (n = 10) were applied by a single operator in a prospective randomized manner. Histamine (1 and 6 mg/mL) and control diluent were introduced at 6 randomized locations onto the upper and lower arms of healthy subjects. Wheal and flare reactions were measured independently by 2 masked technicians. Twenty-four subjects provided consent, and 768 skin tests were placed. Mean wheal diameter among devices differed from 3.0 mm (ComforTen; Hollister-Stier, Spokane, Wash) to 6.8 mm (UniTest PC; Lincoln Diagnostics, Decatur, Ill) using 1 mg/mL histamine (P Diagnostics, Decatur, Ill; and Sharp-Test; Panatrex, Placentia, Calif) using 6 mg/mL histamine (P pain score of less than 4 on a 10-point visual analog scale. Pain scores were higher among women, but this did not reach statistical significance. The Multi-Test PC and the UniTest PC had the lowest pain scores compared with the other devices. All 10 skin prick test devices displayed good analytical sensitivity and specificity; however, 3 mm cannot arbitrarily be used as a positive threshold. The use of histamine at 1 mg/mL is unacceptable for certain devices but may be preferable for the most sensitive devices. On average, there was no pain score difference between multiheaded and single-head devices. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Measurement of the force–displacement response of in vivo human skin under a rich set of deformations

KAUST Repository

Flynn, Cormac; Taberner, Andrew; Nielsen, Poul

2011-01-01

The non-linear, anisotropic, and viscoelastic properties of human skin vary according to location on the body, age, and individual. The measurement of skin's mechanical properties is important in several fields including medicine, cosmetics, and forensics. In this study, a novel force-sensitive micro-robot applied a rich set of three-dimensional deformations to the skin surface of different areas of the arms of 20 volunteers. The force-displacement response of each area in different directions was measured. All tested areas exhibited a non-linear, viscoelastic, and anisotropic force-displacement response. There was a wide quantitative variation in the stiffness of the response. For the right anterior forearm, the ratio of the maximum probe reaction force to maximum probe displacement ranged from 0.44Nmm-1 to 1.45Nmm-1. All volunteers exhibited similar qualitative anisotropic characteristics. For the anterior right forearm, the stiffest force-displacement response was when the probe displaced along the longitudinal axis of the forearm. The response of the anterior left forearm was stiffest in a direction 20° to the longitudinal axis of the forearm. The posterior upper arm was stiffest in a direction 90° to the longitudinal axis of the arm. The averaged posterior upper arm response was less stiff than the averaged anterior forearm response. The maximum probe force at 1.3mm probe displacement was 0.69N for the posterior upper arm and 1.1N for the right anterior forearm. The average energy loss during the loading-unloading cycle ranged from 11.9% to 34.2%. This data will be very useful for studying the non-linear, anisotropic, and viscoelastic behaviour of skin and also for generating material parameters for appropriate constitutive models. © 2011 IPEM.

Skin-Resident T Cells Drive Dermal Dendritic Cell Migration in Response to Tissue Self-Antigen.

Science.gov (United States)

Ali, Niwa; Zirak, Bahar; Truong, Hong-An; Maurano, Megan M; Gratz, Iris K; Abbas, Abul K; Rosenblum, Michael D

2018-05-01

Migratory dendritic cell (DC) subsets deliver tissue Ags to draining lymph nodes (DLNs) to either initiate or inhibit T cell-mediated immune responses. The signals mediating DC migration in response to tissue self-antigen are largely unknown. Using a mouse model of inducible skin-specific self-antigen expression, we demonstrate that CD103 + dermal DCs (DDCs) rapidly migrate from skin to skin DLN (SDLNs) within the first 48 h after Ag expression. This window of time was characterized by the preferential activation of tissue-resident Ag-specific effector T cells (Teffs), with no concurrent activation of Ag-specific Teffs in SDLNs. Using genetic deletion and adoptive transfer approaches, we show that activation of skin-resident Teffs is required to drive CD103 + DDC migration in response to tissue self-antigen and this Batf3-dependent DC population is necessary to mount a fulminant autoimmune response in skin. Conversely, activation of Ag-specific Teffs in SDLNs played no role in DDC migration. Our studies reveal a crucial role for skin-resident T cell-derived signals, originating at the site of self-antigen expression, to drive DDC migration during the elicitation phase of an autoimmune response. Copyright © 2018 by The American Association of Immunologists, Inc.

Calibration of thermoluminescence skin dosemeter response to beta emitters found in Ontario Hydro nuclear power stations

International Nuclear Information System (INIS)

Walsh, M.L.; Agnew, D.A.; Donnelly, K.E.

1984-01-01

The response of the Ontario Hydro Thermoluminescence Dosimetry System to beta radiation in nuclear power station environments was evaluated. Synthetic beta spectra were constructed, based on activity samples from heat transport systems and fuelling machine contamination smears at nuclear power stations. Using these spectra and dosemeter energy response functions, an overall response factor for the skin dosemeter relative to skin dose at 7 mg.cm -2 was calculated. This calculation was done assuming three specific geometries: (1) an infinite uniformly contaminated plane source at a distance of 33 cm (50 mg.cm -2 total shielding) from the receptor; (2) an infinite cloud surrounding the receptor; (3) a point source at 33 cm. Based on these calculations, a conservative response factor of 0.7 has been chosen. This provides an equation for skin dose assignment, i.e. Skin Dose = 1.4 x Skin Dosemeter Reading when the skin dosemeter is directly calibrated in mGy(gamma). (author)

Natural history of skin prick test reactivity

DEFF Research Database (Denmark)

Schou Nielsen, Jesper; Meteran, Howraman; Ulrik, Charlotte Suppli

2017-01-01

population sample of children and adolescents in relation to symptoms of rhinitis. METHODS: A total of 983 individuals, aged 7 to 17 years, were randomly selected in 1986 and invited to 4 examinations during a 20-year period. During each examination, a skin prick test was performed using common local...

Inhibition of ultraviolet irradiation response of human skin by topical phlogostatic compounds

International Nuclear Information System (INIS)

Weirich, E.G.; Lutz, U.C.

1977-01-01

By adaption of the model of UV dermatitis in human skin a test procedure has been developed which facilitates realistic assessment of topical contra-inflammatory activity of steroidal as well as non-steroidal compounds. Sixt typical skin drug agents were tested according to their reaction inhibition effect. (orig./MG) [de

Modulation of the androgenetic response in diverse skin cell types: the pilosebaceous unit

International Nuclear Information System (INIS)

Zurvarra, F.; Kerner, N.; Hagelin, K.

2009-01-01

Androgens play a central role in diverse morphogenetic processes of the skin. Hair growth and follicular cycle are regulated in part by androgens. Androgens also play a key function, together with other receptors such as the PPARs receptors family, on the proliferation and differentiation of the sebaceous gland that forms part of the pilosebaceous unit and influences hair growth and skin well-being. UV radiation may affect androgens regulation of skin homeostasis. Objectives: to study the modulation of androgenetic response related to UV radiation on the pilosebaceous unit, in two skin conditions: androgenetic alopecia and acne, both affecting skin and constituting major concerns for affected individuals. Methods: primary cultures of cells and established cell lines from the pilosebaceous unit: dermal papillae cells, keratinocytes and sebocytes. Analysis of lipid content, inflammatory response and proliferation of cells under the influence of androgens, PPARs ligands and UVR. Results: sebocytes primary cultures were obtained from human sebaceous glands. Proliferation and differentiation, as well as the expression of proinflammatory molecules (IL-1, TNF alpha, iNOs) and lipogenic enzymes (FASN) under androgens and UV treatment were assessed. The response to androgens under UV exposure was also analyzed in dermal papillae cells in culture. (authors)

Lack of Correlation between Severity of Clinical Symptoms, Skin Test Reactivity, and Radioallergosorbent Test Results in Venom-Allergic Patients

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Warrington RJ

2006-06-01

Full Text Available Abstract Purpose To retrospectively examine the relation between skin test reactivity, venom-specific immunoglobulin E (IgE antibody levels, and severity of clinical reaction in patients with insect venom allergy. Method Thirty-six patients (including 15 females who presented with a history of allergic reactions to insect stings were assessed. The mean age at the time of the reactions was 33.4 ± 15.1 years (range, 4-76 years, and patients were evaluated 43.6 ± 90 months (range, 1-300 months after the reactions. Clinical reactions were scored according to severity, from 1 (cutaneous manifestations only to 3 (anaphylaxis with shock. These scores were compared to scores for skin test reactivity (0 to 5, indicating the log increase in sensitivity from 1 μg/mL to 0.0001 μg/mL and radioallergosorbent test (RAST levels (0 to 4, indicating venom-specific IgE levels, from undetectable to >17.5 kilounits of antigen per litre [kUA/L]. Results No correlation was found between skin test reactivity (Spearman's coefficient = 0.15, p = .377 or RAST level (Spearman's coefficient = 0.32, p = .061 and the severity of reaction. Skin test and RAST scores both differed significantly from clinical severity (p p = .042. There was no correlation between skin test reactivity and time since reaction (Spearman's coefficient = 0.18, p = .294 nor between RAST and time since reaction (r = 0.1353, p = .438. Elimination of patients tested more than 12 months after their reaction still produced no correlation between skin test reactivity (p = .681 or RAST score (p = .183 and the severity of the clinical reaction. Conclusion In venom-allergic patients (in contrast to reported findings in cases of inhalant IgE-mediated allergy, there appears to be no significant correlation between the degree of skin test reactivity or levels of venom-specific IgE (determined by RAST and the severity of the clinical reaction.

Postural vascular response in human skin: passive and active reactions to alteration of transmural pressure.

Science.gov (United States)

Jepsen, H; Gaehtgens, P

1993-09-01

Laser-Doppler (LD) fluxmetry was performed in the palmar finger skin of healthy subjects to study the mechanisms contributing to the postural vascular response. Local transmural pressure in the skin blood vessels of the region studied was altered for 1 min in two experimental series either by passive movement of the arm to different vertical hand positions relative to heart level or by application of external pressure (-120-180 mmHg) to the finger. Heart and respiratory rate, arterial blood pressure, and LD flux in the contralateral finger (kept at heart level) were measured. The measurements suggest a compound reaction of local (myogenic) and systemic (neurogenic) mechanisms: the local regulatory component appears as a graded active vascular response elicited by passive vessel distension or compression. A systemic component, associated with a single deep inspiration, is frequently observed during the actual movement of the arm. In addition, prolonged holding of the test hand in a given vertical position also elicits a delayed vascular response in the control hand at heart level, which may be generated by volume receptors in the intrathoracic low-pressure system.

First-in-man open clinical trial of a combined rdESAT-6 and rCFP-10 tuberculosis specific skin test reagent.

Directory of Open Access Journals (Sweden)

Winnie Bergstedt

2010-06-01

Full Text Available Tuberculin is still the only available skin test reagent for the diagnosis of mycobacterial infection. The product has a remarkable sensitivity, but poor specificity. Previous studies, including two human phase I clinical trials, have indicated that rdESAT-6 has a potential as an improved skin test reagent. Animal studies have shown that the sensitivity may be increased by inclusion of the genetically related CFP-10 antigen in the preparation without loosing specificity.In this study a Lactococcus fermented, recombinant skin test reagent consisting of a 1ratio1 wt/wt of rdESAT-6 and CFP-10 was manufactured according to GMP standards and tested for the first time in 42 healthy adult volunteers. The two doses of 0.01 microg or 0.1 microg were injected intradermally by the Mantoux technique with 6 or 12 weeks interval. No serious adverse events and only mild adverse reactions were reported. The reagent elicited a positive skin test reaction after the first injection in one participant, who most likely was latently infected with M. tuberculosis as indicated by an appreciable IFN gamma response just below the Quantiferon(R cut-off level at the screening visit. None of the remaining participants in the four groups had any skin test reactions and sensitisation by the reagent could therefore be excluded.The investigational skin test reagent rdESAT-6 and CFP-10 appeared safe and non-sensitising in this first-in-man clinical trial in human volunteers and can now be tested in larger clinical trials involving individuals with latent M. tuberculosis infection or active TB disease.ClinicalTrials.gov NCT00793702.

Validation of artificial skin equivalents as in vitro testing systems

Science.gov (United States)

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.

Design, Fabrication, and Testing of Active Skin Antenna with 3D Printing Array Framework

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Jinzhu Zhou

2017-01-01

Full Text Available An active skin antenna with structural load-bearing and electromagnetic functions is usually installed in the structural surface of mobile vehicles such as aircrafts, warships, and high-speed train. This paper presents the design, fabrication, and testing of a novel active skin antenna which consists of an encapsulation shell, antenna skin, and RF and beam control circuits. The antenna skin which consists of the facesheet, honeycomb, array framework, and microstrip antenna elements was designed by using Bayesian optimization, in order to improve the design efficiency. An active skin antenna prototype with 32 microstrip antenna elements was fabricated by using a hybrid manufacturing method. In this method, 3D printing technology was applied to fabricate the array framework, and the different layers were bonded to form the final antenna skin by using traditional composite process. Some experimental testing was conducted, and the testing results validate the feasibility the proposed antenna skin structure. The proposed design and fabrication technique is suitable for the development of conformal load-bearing antenna or smart skin antenna installed in the structural surface of aircraft, warships, and armored vehicles.

Tuberculous Lymphadenitis: Skin Delayed-Type Hypersensitivity ...

African Journals Online (AJOL)

Tuberculous Lymphadenitis: Skin Delayed-Type Hypersensitivity Reaction and Cellular Immune Responses. ... The tuberculin skin test (TST) and peripheral blood mono-nuclear cells (PBMCs) culture were conducted using PPD. The cytokines were measured using commercial kits. Results: The mean TST was 24.6 ±8.0 ...

Tuberculosis skin testing, anergy and protein malnutrition in Peru.

Science.gov (United States)

Pelly, T F; Santillan, C F; Gilman, R H; Cabrera, L Z; Garcia, E; Vidal, C; Zimic, M J; Moore, D A J; Evans, C A

2005-09-01

Malnutrition and intestinal parasites cause immunosuppression. This may cause false-negative tuberculin skin tests (TST) and failure to identify tuberculosis (TB) infection. To assess factors associated with TST positivity and anergy in disadvantaged communities in Peru. A study of 212 randomly selected adults: 102 in a rural Amazonian village and 110 shanty town residents in urban Lima. Respectively 52% and 53% of urban and rural jungle populations were TST-positive. Using simultaneous tetanus and candida skin tests, 99% had at least one positive skin test. Generalised anergy was therefore rare, despite frequent intestinal parasitic infection, including 34% helminth infection prevalence in the jungle. TST positivity was associated with age (P = 0.001), known TB contact (P = 0.02) and poor household ventilation (P = 0.007). TST positivity was not significantly associated with crowding, reported past TB, single/multiple BCG vaccination, income, intestinal parasites, dietary factors, body mass index or body fat. Individuals with lower anthropometric body protein, as measured by corrected arm muscle area, were less likely to be TST-positive (P = 0.02), implying that protein malnutrition caused tuberculin-specific anergy. These results identify the importance of household ventilation for community TB transmission and add to the evidence that protein malnutrition suppresses TB immunity, causing false-negative TST results.

Influence of trichloroacetic acid peeling on the skin stress response system.

Science.gov (United States)

Kimura, Ayako; Kanazawa, Nobuo; Li, Hong-Jin; Yonei, Nozomi; Yamamoto, Yuki; Furukawa, Fukumi

2011-08-01

Although trichloroacetic acid (TCA) peeling is widely applied for cosmetic treatment of photodamaged skin, the entire biological mechanisms have yet to be determined. The skin stress response system (SSRS) involves corticotropin-releasing hormone (CRH) and proopiomelanocortin (POMC) products that are locally-generated in response to locally-provided stressors or pro-inflammatory cytokines. This system would restrict tissue damage and restore local homeostasis. To determine the influence of TCA peeling on the SSRS in vitro and in vivo, expressions of POMC, melanocortin receptor 1 (MC1R), CRH and CRH receptor 1 (CRHR1) mRNA were examined by reverse transcription polymerase chain reaction in Pam212 murine keratinocytes, murine plantar and healthy human abdominal skin specimens after TCA treatment. In addition, their protein expressions as well as those of POMC-derived peptides were examined immunohistochemically. After TCA treatment, transient upregulation of POMC and MC1R mRNA expressions was observed in both murine and human skin, as well as in Pam212. Enhanced POMC protein, recovery of once-impaired MC1R protein, and no enhancement of POMC-derived peptide productions were revealed immunohistochemically in both murine and human epidermis. In contrast, neither expression levels of CRH and CRHR1 mRNA nor epidermal protein were enhanced after TCA application in murine and human skin, except for induction of human CRH mRNA expression. These results suggest that TCA activates the SSRS by inducing POMC and MC1R productions of keratinocytes in the CRH-independent manner, and that the biological effects of POMC itself are responsible for the TCA-induced epidermal SSRS activation. © 2010 Japanese Dermatological Association.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Effects of self-foot reflexology on stress, fatigue, skin temperature and immune response in female undergraduate students].

Science.gov (United States)

Lee, Young-Mee

2011-02-01

The purpose of this study was to evaluate the effects of self-foot reflexology on stress (perceived stress, urine cortisol level, and serum cortisol level), fatigue, skin temperature and immune response in female undergraduate students. The research design was a nonequivalent control group pretest-post test design. Participants were 60 university students: 30 in the experiment group and 30 in the control group. The period of this study was from April to June 2010. The program was performed for 1 hr a session, three times a week for 6 weeks. The data were analyzed using the SPSS/WIN 17.0 program. The results showed that self-foot reflexology was effective in reducing perceived stress and fatigue, and raised skin temperature in female undergraduate students. But cortisol levels and immune response were not statistically significant different. The results of this study indicate that self-foot reflexology is an effective nursing intervention in reducing perceived stress and fatigue and, in improving skin temperature. Therefore, it is recommended that this be used in clinical practice as an effective nursing intervention for in female undergraduate students.

Immune sensitization to methylene diphenyl diisocyanate (MDI resulting from skin exposure: albumin as a carrier protein connecting skin exposure to subsequent respiratory responses

Directory of Open Access Journals (Sweden)

Redlich Carrie A

2011-03-01

Full Text Available Abstract Background Methylene diphenyl diisocyanate (MDI, a reactive chemical used for commercial polyurethane production, is a well-recognized cause of occupational asthma. The major focus of disease prevention efforts to date has been respiratory tract exposure; however, skin exposure may also be an important route for inducing immune sensitization, which may promote subsequent airway inflammatory responses. We developed a murine model to investigate pathogenic mechanisms by which MDI skin exposure might promote subsequent immune responses, including respiratory tract inflammation. Methods Mice exposed via the skin to varying doses (0.1-10% w/v of MDI diluted in acetone/olive oil were subsequently evaluated for MDI immune sensitization. Serum levels of MDI-specific IgG and IgE were measured by enzyme-linked immunosorbant assay (ELISA, while respiratory tract inflammation, induced by intranasal delivery of MDI-mouse albumin conjugates, was evaluated based on bronchoalveolar lavage (BAL. Autologous serum IgG from "skin only" exposed mice was used to detect and guide the purification/identification of skin proteins antigenically modified by MDI exposure in vivo. Results Skin exposure to MDI resulted in specific antibody production and promoted subsequent respiratory tract inflammation in animals challenged intranasally with MDI-mouse albumin conjugates. The degree of (secondary respiratory tract inflammation and eosinophilia depended upon the (primary skin exposure dose, and was maximal in mice exposed to 1% MDI, but paradoxically limited in mice receiving 10-fold higher doses (e.g. 10% MDI. The major antigenically-modified protein at the local MDI skin exposure site was identified as albumin, and demonstrated biophysical changes consistent with MDI conjugation. Conclusions MDI skin exposure can induce MDI-specific immune sensitivity and promote subsequent respiratory tract inflammatory responses and thus, may play an important role in MDI asthma

Testing a linear time invariant model for skin conductance responses by intraneural recording and stimulation.

Science.gov (United States)

Gerster, Samuel; Namer, Barbara; Elam, Mikael; Bach, Dominik R

2018-02-01

Skin conductance responses (SCR) are increasingly analyzed with model-based approaches that assume a linear and time-invariant (LTI) mapping from sudomotor nerve (SN) activity to observed SCR. These LTI assumptions have previously been validated indirectly, by quantifying how much variance in SCR elicited by sensory stimulation is explained under an LTI model. This approach, however, collapses sources of variability in the nervous and effector organ systems. Here, we directly focus on the SN/SCR mapping by harnessing two invasive methods. In an intraneural recording experiment, we simultaneously track SN activity and SCR. This allows assessing the SN/SCR relationship but possibly suffers from interfering activity of non-SN sympathetic fibers. In an intraneural stimulation experiment under regional anesthesia, such influences are removed. In this stimulation experiment, about 95% of SCR variance is explained under LTI assumptions when stimulation frequency is below 0.6 Hz. At higher frequencies, nonlinearities occur. In the intraneural recording experiment, explained SCR variance is lower, possibly indicating interference from non-SN fibers, but higher than in our previous indirect tests. We conclude that LTI systems may not only be a useful approximation but in fact a rather accurate description of biophysical reality in the SN/SCR system, under conditions of low baseline activity and sporadic external stimuli. Intraneural stimulation under regional anesthesia is the most sensitive method to address this question. © 2017 The Authors. Psychophysiology published by Wiley Periodicals, Inc. on behalf of Society for Psychophysiological Research.

Using ELISPOT to expose false positive skin test conversion in tuberculosis contacts.

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Philip C Hill

2007-01-01

Full Text Available Repeat tuberculin skin tests may be false positive due to boosting of waned immunity to past mycobacterial exposure. We evaluated whether an ELISPOT test could identify tuberculosis (TB contacts with boosting of immunity to non-tuberculous mycobacterial exposure.We conducted tuberculin and ELISPOT tests in 1665 TB contacts: 799 were tuberculin test negative and were offered a repeat test after three months. Those with tuberculin test conversion had an ELISPOT, chest X-ray and sputum analysis if appropriate. We compared converters with non-converters, assessed the probability of each of four combinations of ELISPOT results over the two time points and estimated boosting with adjustment for ELISPOT sensitivity and specificity. 704 (72% contacts had a repeat tuberculin test; 176 (25% had test conversion, which increased with exposure to a case (p = 0.002, increasing age (p = 0.0006 and BCG scar (p = 0.06. 114 tuberculin test converters had ELISPOT results: 16(14% were recruitment positive/follow-up positive, 9 (8% positive/negative, 34 (30% negative/positive, and 55 (48% were negative/negative. There was a significant non-linear effect of age for ELISPOT results in skin test converters (p = 0.038. Estimates of boosting ranged from 32%-41% of skin test converters with increasing age. Three converters were diagnosed with TB, two had ELISPOT results: both were positive, including one at recruitment.We estimate that approximately one third of tuberculin skin test conversion in Gambian TB case contacts is due to boosting of immunity to non-tuberculous mycobacterial exposure. Further longitudinal studies are required to confirm whether ELISPOT can reliably identify case contacts with tuberculin test conversion that would benefit most from prophylactic treatment.

Response of Human Skin Equivalents to Sarcoptes scabiei

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MORGAN, MARJORIE S.; ARLIAN, LARRY G.

2010-01-01

Studies have shown that molecules in an extract made from bodies of the ectoparasitic mite, Sarcoptes scabiei De Geer, modulate cytokine secretion from cultured human keratinocytes and fibroblasts. In vivo, in the parasitized skin, these cells interact with each other by contact and cytokine mediators and with the matrix in which they reside. Therefore, these cell types may function differently together than they do separately. In this study, we used a human skin equivalent (HSE) model to investigate the influence of cellular interactions between keratinocytes and fibroblasts when the cells were exposed to active/burrowing scabies mites, mite products, and mite extracts. The HSE consisted of an epidermis of stratified stratum corneum, living keratinocytes, and basal cells above a dermis of fibroblasts in a collagen matrix. HSEs were inoculated on the surface or in the culture medium, and their cytokine secretions on the skin surface and into the culture medium were determined by enzyme-linked immunosorbent assay. Active mites on the surface of the HSE induced secretion of cutaneous T cell-attracting chemokine, thymic stromal lymphopoietin, interleukin (IL)-1α, IL-1β, IL-1 receptor antagonist (IL-1ra), IL-6, IL-8, monocyte chemoattractant protein-1, granulocyte/macrophage colony-stimulating factor, and macrophage colony-stimulating factor. The main difference between HSEs and monocultured cells was that the HSEs produced the proinflammatory cytokines IL-1α and IL-1β and their competitive inhibitor IL-1ra, whereas very little of these mediators was previously found for cultured keratinocytes and fibroblasts. It is not clear how the balance between these cytokines influences the overall host response. However, IL-1ra may contribute to the depression of an early cutaneous inflammatory response to scabies in humans. These contrasting results illustrate that cell interactions are important in the host’s response to burrowing scabies mites. PMID:20939384

Where to prick the apple for skin testing?

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Vlieg-Boerstra, B J; van de Weg, W E; van der Heide, S; Dubois, A E J

2013-09-01

Mal d 1 is not equally distributed over the apple. We aimed to examine the influence of the location of pricking in the apple on prick-to-prick skin prick test (PTP) results. PTPs were performed in autumn 2007 and spring 2008, before the birch pollen season, in 32 Dutch adults with symptoms of oral allergy to fresh apple, using apples harvested in autumn 2007. PTPs with fresh intact and unpeeled Pink Lady, Golden Delicious, Elise, Santana and Modi apples were performed using material obtained from approximately 2 cm near the stalk (top), and the middle region. All PTP responses were greater when performed with apple material near the stalk than from the middle region. In 2007, these differences were statistically significant for Pink Lady, Golden Delicious and Elise, and in 2008, for Pink Lady and Modi. When performing PTPs, the apple should be pricked near the stalk rather than in the middle. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of the early local immune response to Ixodes ricinus tick bites in human skin.

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Glatz, Martin; Means, Terry; Haas, Josef; Steere, Allen C; Müllegger, Robert R

2017-03-01

Little is known about the immunomodulation by tick saliva during a natural tick bite in human skin, the site of the tick-host interaction. We examined the expression of chemokines, cytokines and leucocyte markers on the mRNA levels and histopathologic changes in human skin biopsies of tick bites (n=37) compared to unaffected skin (n=9). Early tick-bite skin lesions (skin. With longer tick attachment (>24 hours), the numbers of innate immune cells and mediators (not significantly) declined, whereas the numbers of lymphocytes (not significantly) increased. Natural tick bites by Ixodes ricinus ticks initially elicit a strong local innate immune response in human skin. Beyond 24 hours of tick attachment, this response usually becomes less, perhaps because of immunomodulation by tick saliva. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Erythema exsudativum multiforme after a Leishmania skin test

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Wind, Bas S.; Guimarães, Luiz H.; Machado, Paulo R. L.

2014-01-01

A 45-year-old otherwise healthy male from an endemic region for Leishmania braziliensis infection in Bahia, Brazil, presented with three erosive hemorrhagic infiltrated plaques on the left shin accompanied with lymphadenopathy in the groin since one month. A Leishmania skin test performed on the

Elastin hydrolysate derived from fish enhances proliferation of human skin fibroblasts and elastin synthesis in human skin fibroblasts and improves the skin conditions.

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Shiratsuchi, Eri; Nakaba, Misako; Yamada, Michio

2016-03-30

Recent studies have shown that certain peptides significantly improve skin conditions, such as skin elasticity and the moisture content of the skin of healthy woman. This study aimed to investigate the effects of elastin hydrolysate on human skin. Proliferation and elastin synthesis were evaluated in human skin fibroblasts exposed to elastin hydrolysate and proryl-glycine (Pro-Gly), which is present in human blood after elastin hydrolysate ingestion. We also performed an ingestion test with elastin hydrolysate in humans and evaluated skin condition. Elastin hydrolysate and Pro-Gly enhanced the proliferation of fibroblasts and elastin synthesis. Maximal proliferation response was observed at 25 ng mL(-1) Pro-Gly. Ingestion of elastin hydrolysate improved skin condition, such as elasticity, number of wrinkles, and blood flow. Elasticity improved by 4% in the elastin hydrolysate group compared with 2% in the placebo group. Therefore, elastin hydrolysate activates human skin fibroblasts and has beneficial effects on skin conditions. © 2015 Society of Chemical Industry.

Influence of chemical peeling on the skin stress response system.

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Kimura, Ayako; Kanazawa, Nobuo; Li, Hong-Jin; Yonei, Nozomi; Yamamoto, Yuki; Furukawa, Fukumi

2012-07-01

Skin stress response system (SSRS) involves corticotropin-releasing hormone (CRH) and proopiomelanocortin (POMC)-derived peptides, such as adrenocorticotropic hormone (ACTH), a-melanocyte-stimulating hormone (MSH) and b-endorphin that are locally generated in response to locally provided stressors or proinflammatory cytokines. This system would restrict tissue damage and restore local homoeostasis. Trichloroacetic acid (TCA) is one of the most widely used peeling agents and applied for cosmetic treatment of photodamaged skin. However, the biological mechanism responsible for TCA peeling has yet to be fully determined. While our investigation focused on the inflammation and wound healing pathways, in the recent study, we have examined involvement of the SSRS as the third pathway. Mostly depending on our findings that TCA peeling activates the SSRS by inducing the POMC expression of keratinocytes in the CRH-independent manner, together with the results reported by other researchers, we can say that the biological effect of POMC seems to be responsible for the TCA-induced epidermal SSRS activation. © 2012 John Wiley & Sons A/S.

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

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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.

The colour of blood in skin: a comparison of Allen's test and photonics simulations.

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Välisuo, Petri; Kaartinen, Ilkka; Kuokkanen, Hannu; Alander, Jarmo

2010-11-01

The colour of the skin reflects many physiological and pathological states of an individual. Usually, the skin colour is examined by the bare eye alone. Several scaling systems have been developed to quantify the sensory evaluation of skin colour. In this work, the reflectance of the skin is measured directly using an objective instrument. Haemoglobin inside the dermal circulation is one of the key factors of skin colour and it also has a major role in the appearance of many skin lesions and scars. To quantitatively measure and analyse such conditions, the relation between the skin colour and the haemoglobin concentration in the skin needs to be resolved. To examine the effect of blood concentration on the skin colour, five Allen's tests were performed on 20 persons. The skin colour change was measured using a spectrophotometer by changing the blood concentration by the Allen's test. Light interaction with the skin was simulated with a Monte Carlo model, tuning the blood concentration parameter until the simulated and the measured spectra matched, yielding the relationship between the skin colour and the blood concentration. The simulation produced spectra similar to those measured. The change in the blood concentration in the simulation model and in the skin produced changes similar to the spectra. The reflectance of the skin was found to be a nonlinear function of the blood concentration. The relationship found between skin colour and blood concentration makes it possible to quantify those skin conditions expressed by blood volume better than plain colour. © 2010 John Wiley & Sons A/S.

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

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

2017-05-01

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. Copyright © 2017 Elsevier B.V. All rights reserved.

CON4EI: SkinEthic™ Human Corneal Epithelium Eye Irritation Test (SkinEthic™ HCE EIT) for hazard identification and labelling of eye irritating chemicals.

Science.gov (United States)

Van Rompay, A R; Alépée, N; Nardelli, L; Hollanders, K; Leblanc, V; Drzewiecka, A; Gruszka, K; Guest, R; Kandarova, H; Willoughby, J A; Verstraelen, S; Adriaens, E

2018-06-01

Assessment of ocular irritancy is an international regulatory requirement and a necessary step in the safety evaluation of industrial and consumer products. Although a number of in vitro ocular irritation assays exist, none are capable of fully categorizing chemicals as a stand-alone assay. Therefore, the CEFIC-LRI-AIMT6-VITO CON4EI (CONsortium for in vitro Eye Irritation testing strategy) project was developed with the goal of assessing the reliability of eight in vitro/alternative test methods as well as establishing an optimal tiered-testing strategy. One of the in vitro assays selected was the validated SkinEthic™ Human Corneal Epithelium Eye Irritation Test method (SkinEthic™ HCE EIT). The SkinEthic™ HCE EIT has already demonstrated its capacity to correctly identify chemicals (both substances and mixtures) not requiring classification and labelling for eye irritation or serious eye damage (No Category). The goal of this study was to evaluate the performance of the SkinEthic™ HCE EIT test method in terms of the important in vivo drivers of classification. For the performance with respect to the drivers all in vivo Cat 1 and No Cat chemicals were 100% correctly identified. For Cat 2 chemicals the liquids and the solids had a sensitivity of 100% and 85.7%, respectively. For the SkinEthic™ HCE EIT test method, 100% concordance in predictions (No Cat versus No prediction can be made) between the two participating laboratories was obtained. The accuracy of the SkinEthic™ HCE EIT was 97.5% with 100% sensitivity and 96.9% specificity. The SkinEthic™ HCE EIT confirms its excellent results of the validation studies. Copyright © 2017. Published by Elsevier Ltd.

IN SITU IMMUNE RESPONSE EVALUATION VIA IMMUNOHISTOCHEMISTRY IN SKIN BIOPSIES FROM PATIENTS AFFECTED BY AUTOIMMUNE BLISTERING DISEASES

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Ana Maria Abreu Velez

2013-11-01

Full Text Available Introduction: The in situ immune response in skin biopsies from patients affected by autoimmune skin blistering diseases (ABD is not well characterized. Aim: Our investigation attempts to immunophenotype cells in lesional skin in several ABD, utilizing immunohistochemistry (ICH. Methods: We tested by IHC for CD4, CD8, CD19, CD20, CD45, CD56/NCAM, PAX-5, granzyme B, myeloperoxidase, neutrophil elastase, LAT and ZAP-70 in patients affected by ABD. We tested 30 patients with endemic pemphigus foliaceus (EPF, 15 controls from the EPF endemic area, and 15 biopsies from healthy controls from the USA. We also tested archival biopsies from patients with selected ABD, including 30 patients with bullous pemphigoid, 20 with pemphigus vulgaris, 8 with pemphigus foliaceus and 14 with dermatitis herpetiformis. Results: We found a predominantly CD8 positive/CD45 positive T cell infiltrate in all ABD. Our skin biopsies demonstrated consistently positive staining for myeloperoxidase, but negative staining for neutrophil elastase. Most ABD biopsies displayed negative staining for CD4 and B cell markers; natural killer cell markers were also rarely seen. ZAP-70 and LAT were frequently detected. In El Bagre-EPF, a significant fragmentation of T cells in lesional skin was noted, as well as autoreactivity to lymph nodes. Conclusions: The documented T cell and myeloperoxidase staining are indicative of the role of T lymphocytes and neutrophils in lesional biopsies in patients with ABD, in addition to previously documented deposition of B cells, immunoglobulins and complement in situ. In El Bagre-EPF, T cells could also target lymph nodes; however, further studies are needed to confirm this possibility.

Membrane properties for permeability testing: Skin versus synthetic membranes.

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Haq, Anika; Dorrani, Mania; Goodyear, Benjamin; Joshi, Vivek; Michniak-Kohn, Bozena

2018-03-25

Synthetic membranes that are utilized in diffusion studies for topical and transdermal formulations are usually porous thin polymeric sheets for example cellulose acetate (CA) and polysulfones. In this study, the permeability of human skin was compared using two synthetic membranes: cellulose acetate and Strat-M® membrane and lipophilic and hydrophilic compounds either as saturated or formulated solutions as well as marketed dosage forms. Our data suggests that hydrophilic compounds have higher permeation in Strat-M membranes compared with lipophilic ones. High variation in permeability values, a typical property of biological membranes, was not observed with Strat-M. In addition, the permeability of Strat-M was closer to that of human skin than that of cellulose acetate (CA > Strat-M > Human skin). Our results suggest that Strat-M with little or no lot to lot variability can be applied in pilot studies of diffusion tests instead of human skin and is a better substitute than a cellulose acetate. Copyright © 2018 Elsevier B.V. All rights reserved.

[Hypersensitivity to platinum salts and taxanes: The value of skin tests and tolerance induction procedures].

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Brault, F; Waton, J; Poreaux, C; Schmutz, J-L; Barbaud, A

2017-11-01

The rate of hypersensitivity reactions to platinum salts (PS) and taxanes (TX) is on the increase. The aim of our study was to show the value of skin testing and efficacy of rapid drug desensitization. This was a retrospective study conducted between January 2007 and February 2016 in patients consulting for immediate or delayed hypersensitivity to PS and TX. Skin prick tests (pT) and intradermal reaction tests (IDR) were performed according to the ENDA/EAACI recommendations. We used a 12-step desensitization protocol for rapid drug desensitization. Among the 99 patients included (30 men, 69 women, age 60.4) PS were suspected in 86 cases and taxanes in 13 cases. Skin tests were positive in 25 patients (7 pT, 18 IDR), 23 for platinum salts and 2 for taxanes. Rapid drug desensitization was proposed in 50 patients and performed in 33 (30 PS and 3 TX), proved effective in 29 patients, with protocol adaptation being necessary in 7 cases, and was ineffective in 4 patients. The skin tests for the latter 4 patients were positive. Seventy-five percent of patients with positive skin tests to oxaliplatin presented hypersensitivity reactions during desensitization, i.e. twice as many as patients having negative skin tests. Two percent of patient for PS and 7% for TX had cross reactivity. This French study confirms the efficacy of the 12-step protocol that allows patients to receive chemotherapy after hypersensitivity reaction. Skin test permits the detection of cross-reactions but their practice must be considered based on the patient's history. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

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

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

2010-02-01

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

Testes cutâneos de hipersensibilidade imediata com o evoluir da idade Positive skin test and age

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Wilma Carvalho Neves Forte

2001-04-01

Full Text Available OBJETIVO: avaliação da positividade aos testes cutâneos de hipersensibilidade imediata em crianças com asma brônquica e/ou rinite alérgica em diferentes faixas etárias. CASUÍSTICA E MÉTODOS: foi observada a positividade aos testes cutâneos de hipersensibilidade imediata, por testes de puntura, frente a diferentes alérgenos de mesma procedência: poeira total e Dermatophagóides sp, Dermatophagoides pteronyssinus, Dermatophagoides farinae e Blomia tropicalis, Penicillium sp, Alternaria alternata, Cladosporium herbarium, Aspergillus fumigatus, grama bermuda, capim de pasto, epitélio de cão, epitélio de gato, penas, Blatella germanica, lã. Foram selecionadas 713 crianças divididas em grupos conforme a faixa etária: grupo I (6 a 11 meses, II (1 a 3 anos e 11 meses, III (4 a 8 anos e 11 meses e IV (9 a 15 anos. Para análise estatística utilizou-se o cálculo do qui-quadrado. RESULTADOS: o total de diferenças significativas entre os vários grupos foi: I e II = 5; II e III = 5; II e IV = 5; III e IV = 6; I e III = 10 e I e IV = 10 CONCLUSÃO: concluiu-se que a positividade ao teste de hipersensibilidade imediata foi maior com o evoluir da idade, havendo positividade já aos doze meses de vida, sendo esta positividade significativamente maior a partir de quatro anos de idade.OBJECTIVE: to evaluate positive responses to skin tests for immediate hypersensitivity to allergens in children with asthma and rhinitis at different ages. METHOD: we observed positive skin test reactivity in prick tests using fifteen allergens of same origin (total dust and Dermatophagoides sp.; Dermatophagoides pteronyssinus; Dermatophagoides farinae; Blomia tropicalis; Penicillium sp; Alternaria alternata; Cladosporium herbarium; Aspergillus fumigatus; Bermuda grass; forage grass; dog and cat epithelia; feathers; Blatella germanica and wool. We placed 713 selected patients into different age groups - Group I: 6 to 11 months; Group II: 1 to 3 years and 11

Skin signs in Ehlers-Danlos syndrome: clinical tests and para-clinical methods

DEFF Research Database (Denmark)

Remvig, Lars; Duhn, Ph; Ullman, S

2010-01-01

Objective: The criteria for Ehlers-Danlos syndrome (EDS) and the hypermobility syndrome (HMS) should be reliable. Examination for general joint hypermobility has high reliability but there is only sparse information on the reliability of skin tests, and no information on the level of normal skin...

Skin signs in Ehlers-Danlos syndrome: clinical tests and para-clinical methods

DEFF Research Database (Denmark)

Remvig, L; Duhn, Ph; Ullman, S

2010-01-01

The criteria for Ehlers-Danlos syndrome (EDS) and the hypermobility syndrome (HMS) should be reliable. Examination for general joint hypermobility has high reliability but there is only sparse information on the reliability of skin tests, and no information on the level of normal skin extensibility...

Age influences the skin reaction pattern to mechanical stress and its repair level through skin care products.

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Zouboulis, Christos C; Elewa, Rana; Ottaviani, Monica; Fluhr, Joachim; Picardo, Mauro; Bernois, Armand; Heusèle, Catherine; Camera, Emanuela

2018-03-01

Skin aging is associated with alterations of surface texture, sebum composition and immune response. Mechanical stress induces repair mechanisms, which may be dependent on the age and quality of the skin. The response to mechanical stress in young and aged individuals, their subjective opinion and the objective effectiveness of skin care products were evaluated by biophysical skin quality parameters (stratum corneum hydration, transepidermal water loss, skin pH, pigmentation and erythema) at baseline, 1, 6, 24h and 7days at the forearms of 2 groups of healthy volunteers, younger than 35 years (n=11) and older than 60 years (n=13). In addition, casual surface lipid composition was studied under the same conditions at the baseline and day 7 after mechanical stress induction. Evaluations were also performed in stressed skin areas treated daily with skin care products and the subjective opinion of the volunteers was additionally documented. The tested groups exhibited age-associated baseline skin functions as well as casual surface lipid composition and different reaction patterns to mechanical stress. Skin care was more effective in normalizing skin reaction to stress in the young than in the aged group. The subjective volunteer opinion correlated with the objective measurements. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of adjuvants on responses to skin immunization by microneedles coated with influenza subunit vaccine.

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William C Weldon

Full Text Available Recent studies have demonstrated the effectiveness of vaccine delivery to the skin by vaccine-coated microneedles; however there is little information on the effects of adjuvants using this approach for vaccination. Here we investigate the use of TLR ligands as adjuvants with skin-based delivery of influenza subunit vaccine. BALB/c mice received 1 µg of monovalent H1N1 subunit vaccine alone or with 1 µg of imiquimod or poly(I:C individually or in combination via coated microneedle patches inserted into the skin. Poly(I:C adjuvanted subunit influenza vaccine induced similar antigen-specific immune responses compared to vaccine alone when delivered to the skin by microneedles. However, imiquimod-adjuvanted vaccine elicited higher levels of serum IgG2a antibodies and increased hemagglutination inhibition titers compared to vaccine alone, suggesting enhanced induction of functional antibodies. In addition, imiquimod-adjuvanted vaccine induced a robust IFN-γ cellular response. These responses correlated with improved protection compared to influenza subunit vaccine alone, as well as reduced viral replication and production of pro-inflammatory cytokines in the lungs. The finding that microneedle delivery of imiquimod with influenza subunit vaccine induces improved immune responses compared to vaccine alone supports the use of TLR7 ligands as adjuvants for skin-based influenza vaccines.

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

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

2012-11-01

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. 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. 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. Our results showed that this specific cocktail could represent a potential candidate for a new skin diagnostic test for TB.

Dual skin tests with Mycobacterium avium sensitin and PPD to detect misdiagnosis of latent tuberculosis infection.

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Larson, E M; O'Donnell, M; Chamblee, S; Horsburgh, C R; Marsh, B J; Moreland, J D; Johnson, L S; von Reyn, C Fordham

2011-11-01

A positive tuberculin skin test (TST) may indicate cross-reacting immunity to non-tuberculous mycobacteria (NTM) and not latent tuberculosis infection (LTBI). To assess misclassification of LTBI, as assessed by skin testing with Mycobacterium avium sensitin (MaS), and to determine how this misclassification affects the analysis of risk factors for LTBI. In a population-based survey, participants underwent skin testing with M. tuberculosis purified protein derivative (PPD) and MaS. A PPD-dominant skin test was a reaction that was ≥ 3 mm larger than the MaS reaction; a MaS-dominant skin test was a reaction that was ≥ 3 mm larger than the PPD reaction. Of 447 randomly selected persons, 135 (30%) had a positive PPD test. Of these, 21 (16%) were MaS- dominant, and were therefore attributable to NTM and misclassified as LTBI. PPD reactions of 5-14 mm were more likely to be misclassified than those ≥ 15 mm (OR = 5.0, 95%CI 1.9-13.2). Adjusting for misclassification had only a small impact on the analysis of risk factors for LTBI. A substantial number of individuals who are diagnosed with LTBI are actually sensitized to NTM. Using dual skin testing would reduce misdiagnosis and prevent unnecessary treatment.

Skin bank development and critical incident response.

Science.gov (United States)

Hamilton, Kellie T; Herson, Marisa R

2011-05-01

The Donor Tissue Bank of Victoria (DTBV), situated in Melbourne, Australia developed a skin banking program in 1994. It remains Australia's only operational skin bank, processing cryopreserved human cadaveric skin for the treatment of burns. The demand for allograft skin in Australia has steadily increased since the development of the program. The bank has been involved in the provision of skin for a number of critical incidences or disasters both in Australia and overseas. Demand always exceeds supply, and in the absence of other local skin banks, the DTBV has needed to develop strategies to enable increased provision of allograft skin nationally.

Validation of the cephalosporin intradermal skin test for predicting immediate hypersensitivity: a prospective study with drug challenge.

Science.gov (United States)

Yoon, S-Y; Park, S Y; Kim, S; Lee, T; Lee, Y S; Kwon, H-S; Cho, Y S; Moon, H-B; Kim, T-B

2013-07-01

Cephalosporin is a major offending agent in terms of drug hypersensitivity along with penicillin. Cephalosporin intradermal skin tests (IDTs) have been widely used; however, their validity for predicting immediate hypersensitivity has not been studied. This study aimed to determine the predictive value of cephalosporin intradermal skin testing before administration of the drug. We prospectively conducted IDTs with four cephalosporins, one each of selected first-, second-, third-, or fourth-generation cephalosporins: ceftezol; cefotetan or cefamandole; ceftriaxone or cefotaxime; and flomoxef, respectively, as well as with penicillin G. After the skin test, whatever the result, one of the tested cephalosporins was administered intravenously and the patient was carefully observed. We recruited 1421 patients who required preoperative cephalosporins. Seventy-four patients (74/1421, 5.2%) were positive to at least one cephalosporin. However, none of responders had immediate hypersensitivity reactions after a challenge dose of the same or different cephalosporin, which were positive in the skin test. Four patients who suffered generalized urticaria and itching after challenge gave negative skin tests for the corresponding drug. The IDT for cephalosporin had a sensitivity of 0%, a specificity of 97.5%, a negative predictive value of 99.7%, and a positive predictive value (PPV) of 0%, when challenged with the same drugs that were positive in the skin test. Routine skin testing with a cephalosporin before its administration is not useful for predicting immediate hypersensitivity because of the extremely low sensitivity and PPV of the skin test (CRIS registration no. KCT0000455). © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Skin response to X-irradiation in the guinea-pig

Energy Technology Data Exchange (ETDEWEB)

Berry, R J; Mole, R H; Barnes, D W.H. [Medical Research Council, Harwell (UK). Radiobiological Research Unit

1976-12-01

Skin reaction to X-irradiation has been studied in the albino quinea-pig; early response in limited-field irradiations of the flank was comparable to that commonly seen in rodents, swine and man, and was dose-dependent with a dynamic range from mild erythema to moist desquamation. The peak early skin reaction was seen between 14 and 21 days after irradiation, and declined before 30 days except at the highest doses used. Fractionation of the X-ray dose at 24 hours resulted in a 'sparing' of about 340 rad. Permanent partial epilation was detectable at doses in excess of 1400 rad, and complete epilation at 1 year occurred in 50 per cent of irradiated fields at 1740 rad. Twenty-four hour two-dose fractionation resulted in a 'sparing' of about 500 rad for epilation. Palpable dermal 'fibrosis' was detectable at 3 months after irradiation in fields given more than 2070 rad, and at 1 year after irradiation in fields given more than 1800 rad; 50 per cent of fields showed palpable 'fibrosis' at 1 year at 1930 rad. Unlike domestic swine and man, skin fields in the quinea-pig showed no dimensional contraction after X-ray doses which produced gross early skin damage.

Where to prick the apple for skin testing?

NARCIS (Netherlands)

Vlieg-Boerstra, B. J.; van de Weg, W. E.; van der Heide, S.; Dubois, A. E. J.

Mal d 1 is not equally distributed over the apple. We aimed to examine the influence of the location of pricking in the apple on prick-to-prick skin prick test (PTP) results. PTPs were performed in autumn 2007 and spring 2008, before the birch pollen season, in 32 Dutch adults with symptoms of oral

Where to prick the apple for skin testing?

NARCIS (Netherlands)

Vlieg-Boerstra, B.J.; Weg, van de W.E.; Heide, van der S.; Dubois, A.E.J.

2013-01-01

Mal d 1 is not equally distributed over the apple. We aimed to examine the influence of the location of pricking in the apple on prick-to-prick skin prick test (PTP) results. PTPs were performed in autumn 2007 and spring 2008, before the birch pollen season, in 32 Dutch adults with symptoms of oral

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

GA(2)LEN skin test study II: clinical relevance of inhalant allergen sensitizations in Europe

DEFF Research Database (Denmark)

Burbach, G J; Heinzerling, L M; Edenharter, G

2009-01-01

BACKGROUND: Skin prick testing is the standard for diagnosing IgE-mediated allergies. A positive skin prick reaction, however, does not always correlate with clinical symptoms. A large database from a Global Asthma and Allergy European Network (GA(2)LEN) study with data on clinical relevance was ...... the clinical relevance of positive skin prick tests and calls for further studies, which may, ultimately, help increase the positive predictive value of allergy testing.......BACKGROUND: Skin prick testing is the standard for diagnosing IgE-mediated allergies. A positive skin prick reaction, however, does not always correlate with clinical symptoms. A large database from a Global Asthma and Allergy European Network (GA(2)LEN) study with data on clinical relevance...... was used to determine the clinical relevance of sensitizations against the 18 most frequent inhalant allergens in Europe. The study population consisted of patients referred to one of the 17 allergy centres in 14 European countries (n = 3034, median age = 33 years). The aim of the study was to assess...

Identification of low allergenic apple cultivars using skin prick tests and oral food challenge tests

NARCIS (Netherlands)

Vlieg-Boerstra, B.J.; Weg, van de W.E.; Heide, van der S.; Arens, P.F.P.; Heijerman-Peppelman, G.; Dubois, A.E.J.

2011-01-01

Background: As oral allergy syndrome (OAS) symptoms to apple are frequent, we aimed to identify low allergenic apple cultivars and to validate the prick-to-prick skin prick test (SPT) as a suitable screening method. Methods: Sixty-eight apple cultivars were tested by SPTs in 33 Dutch adults with

The effect of surface wave propagation on neural responses to vibration in primate glabrous skin.

Directory of Open Access Journals (Sweden)

Louise R Manfredi

Full Text Available Because tactile perception relies on the response of large populations of receptors distributed across the skin, we seek to characterize how a mechanical deformation of the skin at one location affects the skin at another. To this end, we introduce a novel non-contact method to characterize the surface waves produced in the skin under a variety of stimulation conditions. Specifically, we deliver vibrations to the fingertip using a vibratory actuator and measure, using a laser Doppler vibrometer, the surface waves at different distances from the locus of stimulation. First, we show that a vibration applied to the fingertip travels at least the length of the finger and that the rate at which it decays is dependent on stimulus frequency. Furthermore, the resonant frequency of the skin matches the frequency at which a subpopulation of afferents, namely Pacinian afferents, is most sensitive. We show that this skin resonance can lead to a two-fold increase in the strength of the response of a simulated afferent population. Second, the rate at which vibrations propagate across the skin is dependent on the stimulus frequency and plateaus at 7 m/s. The resulting delay in neural activation across locations does not substantially blur the temporal patterning in simulated populations of afferents for frequencies less than 200 Hz, which has important implications about how vibratory frequency is encoded in the responses of somatosensory neurons. Third, we show that, despite the dependence of decay rate and propagation speed on frequency, the waveform of a complex vibration is well preserved as it travels across the skin. Our results suggest, then, that the propagation of surface waves promotes the encoding of spectrally complex vibrations as the entire neural population is exposed to essentially the same stimulus. We also discuss the implications of our results for biomechanical models of the skin.

Distribution of T Cells in Rainbow Trout (Oncorhynchus mykiss) Skin and Responsiveness to Viral Infection

Science.gov (United States)

Leal, Esther; Granja, Aitor G.; Zarza, Carlos; Tafalla, Carolina

2016-01-01

Although the skin constitutes the first line of defense against waterborne pathogens, there is a great lack of information regarding the skin associated lymphoid tissue (SALT) and whether immune components of the skin are homogeneously distributed through the surface of the fish is still unknown. In the current work, we have analyzed the transcription of several immune genes throughout different rainbow trout (Oncorhynchus mykiss) skin areas. We found that immunoglobulin and chemokine gene transcription levels were higher in a skin area close to the gills. Furthermore, this skin area as well as other anterior sections also transcribed significantly higher levels of many different immune genes related to T cell immunity such as T cell receptor α (TCRα), TCRγ, CD3, CD4, CD8, perforin, GATA3, Tbet, FoxP3, interferon γ (IFNγ), CD40L and Eomes in comparison to posterior skin sections. In agreement with these results, immunohistochemical analysis revealed that anterior skin areas had a higher concentration of CD3+ T cells and flow cytometry analysis confirmed that the percentage of CD8+ T lymphocytes was also higher in anterior skin sections. These results demonstrate for the first time that T cells are not homogeneously distributed throughout the teleost skin. Additionally, we studied the transcriptional regulation of these and additional T cell markers in response to a bath infection with viral hemorrhagic septicemia virus (VHSV). We found that VHSV regulated the transcription of several of these T cell markers in both the skin and the spleen; with some differences between anterior and posterior skin sections. Altogether, our results point to skin T cells as major players of teleost skin immunity in response to waterborne viral infections. PMID:26808410

Skin test concentrations for systemically administered drugs -- an ENDA/EAACI Drug Allergy Interest Group position paper

DEFF Research Database (Denmark)

Brockow, K; Garvey, L H; Aberer, W

2013-01-01

Skin tests are of paramount importance for the evaluation of drug hypersensitivity reactions. Drug skin tests are often not carried out because of lack of concise information on specific test concentrations. The diagnosis of drug allergy is often based on history alone, which is an unreliable...... indicator of true hypersensitivity.To promote and standardize reproducible skin testing with safe and nonirritant drug concentrations in the clinical practice, the European Network and European Academy of Allergy and Clinical Immunology (EAACI) Interest Group on Drug Allergy has performed a literature...... search on skin test drug concentration in MEDLINE and EMBASE, reviewed and evaluated the literature in five languages using the GRADE system for quality of evidence and strength of recommendation. Where the literature is poor, we have taken into consideration the collective experience of the group...

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

Science.gov (United States)

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.

Cooling reduces the cutaneous afferent firing response to vibratory stimuli in glabrous skin of the human foot sole.

Science.gov (United States)

Lowrey, Catherine R; Strzalkowski, Nicholas D J; Bent, Leah R

2013-02-01

Skin on the foot sole plays an important role in postural control. Cooling the skin of the foot is often used to induce anesthesia to determine the role of skin in motor and balance control. The effect of cooling on the four classes of mechanoreceptor in the skin is largely unknown, and thus the aim of the present study was to characterize the effects of cooling on individual skin receptors in the foot sole. Such insight will better isolate individual receptor contributions to balance control. Using microneurography, we recorded 39 single nerve afferents innervating mechanoreceptors in the skin of the foot sole in humans. Afferents were identified as fast-adapting (FA) or slowly adapting (SA) type I or II (FA I n = 16, FA II n = 7, SA I n = 6, SA II n = 11). Receptor response to vibration was compared before and after cooling of the receptive field (2-20 min). Overall, firing response was abolished in 30% of all receptors, and this was equally distributed across receptor type (P = 0.69). Longer cooling times were more likely to reduce firing response below 50% of baseline; however, some afferent responses were abolished with shorter cooling times (2-5 min). Skin temperature was not a reliable indicator of the level of receptor activation and often became uncoupled from receptor response levels, suggesting caution in the use of this parameter as an indicator of anesthesia. When cooled, receptors preferentially coded lower frequencies in response to vibration. In response to a sustained indentation, SA receptors responded more like FA receptors, primarily coding "on-off" events.

Skin conductance response to the pain of others predicts later costly helping.

Directory of Open Access Journals (Sweden)

Grit Hein

Full Text Available People show autonomic responses when they empathize with the suffering of another person. However, little is known about how these autonomic changes are related to prosocial behavior. We measured skin conductance responses (SCRs and affect ratings in participants while either receiving painful stimulation themselves, or observing pain being inflicted on another person. In a later session, they could prevent the infliction of pain in the other by choosing to endure pain themselves. Our results show that the strength of empathy-related vicarious skin conductance responses predicts later costly helping. Moreover, the higher the match between SCR magnitudes during the observation of pain in others and SCR magnitude during self pain, the more likely a person is to engage in costly helping. We conclude that prosocial motivation is fostered by the strength of the vicarious autonomic response as well as its match with first-hand autonomic experience.

Investigating the Effect of Sympathetic Skin Response Parameters on the Psychological Test Scores in Patients with Fibromyalgia Syndrome by Using ANNS

Directory of Open Access Journals (Sweden)

Murat Yıldız

2013-01-01

Full Text Available In this study, psychological tests such as Visual Analogue Pain Scale, Verbal Pain Scale, Beck Depression Inventory, Beck Anxiety Inventory, Hamilton Depression Rating Scale and Hamilton Anxiety Scale were applied to the selected healthy subjects and patients with Fibromyalgia Syndrome (FMS in Suleyman Demirel University, Faculty of Medicine, Department of Physical Medicine and Rehabilitation and the scores were recorded. A measurement system was established in the same department of the university to measure the sympathetic skin response (SSR from the subjects. The SSR was measured and recorded. The parameters such as latency time, maximum amplitude and the elapsed time were calculated by using Matlab software from the recorded SSR data. SSR parameters were added to the scores and diagnosis accuracy percentages of the FMS calculated by using artificial neural networks (ANNs. Obtained results from the simulations showed that the specified parameters of the SSR and FMS were concerned and these parameters can be used as a diagnostic method in FMS.

Effects of niacin restriction on sirtuin and PARP responses to photodamage in human skin.

Directory of Open Access Journals (Sweden)

Claudia A Benavente

Full Text Available Sirtuins (SIRTs and poly(ADP-ribose polymerases (PARPs, NAD(+-dependent enzymes, link cellular energy status with responses to environmental stresses. Skin is frequently exposed to the DNA damaging effects of UV irradiation, a known etiology in skin cancer. Thus, understanding the defense mechanisms in response to UV, including the role of SIRTs and PARPs, may be important in developing skin cancer prevention strategies. Here, we report expression of the seven SIRT family members in human skin. SIRTs gene expressions are progressively upregulated in A431 epidermoid carcinoma cells (SIRTs1 and 3, actinic keratoses (SIRTs 2, 3, 5, 6, and 7 and squamous cell carcinoma (SIRTs 1-7. Photodamage induces dynamic changes in SIRT expression with upregulation of both SIRT1 and SIRT4 mRNAs. Specific losses of SIRT proteins occur early after photodamage followed by accumulation later, especially for SIRT4. Niacin restriction, which decreases NAD(+, the sirtuin substrate, results in an increase in acetylated proteins, upregulation of SIRTs 2 and 4, increased inherent DNA damage, alterations in SIRT responses to photodamage, abrogation of PARP activation following photodamage, and increased sensitivity to photodamage that is completely reversed by repleting niacin. These data support the hypothesis that SIRTs and PARPs play important roles in resistance to photodamage and identify specific SIRTs that respond to photodamage and may be targets for skin cancer prevention.

The nonlinear flexural response of a whole teleost fish: Contribution of scales and skin.

Science.gov (United States)

Szewciw, Lawrence; Zhu, Deju; Barthelat, Francois

2017-12-01

The scaled skin of fish is an intricate system that provides mechanical protection against hard and sharp puncture, while maintaining the high flexural compliance required for unhindered locomotion. This unusual combination of local hardness and global compliance makes fish skin an interesting model for bioinspired protective systems. In this work we investigate the flexural response of whole teleost fish, and how scales may affect global flexural stiffness. A bending moment is imposed on the entire body of a striped bass (Morone saxatilis). Imaging is used to measure local curvature, to generate moment-curvature curves as function of position along the entire axis of the fish. We find that the flexural stiffness is the highest in the thick middle portion of the fish, and lowest in the caudal and rostral ends. The flexural response is nonlinear, with an initial soft response followed by significant stiffening at larger flexural deformations. Low flexural stiffness at low curvatures promotes efficient swimming, while higher stiffness at high curvatures enables a possible tendon effect, where the mechanical energy at the end of a stroke is stored in the form of strain energy in the fish skin. To assess the contribution of the scales to stiffening we performed flexural tests with and without scales, following a careful protocol to take in account tissue degradation and the effects of temperature. Our findings suggest that scales do not substantially increase the whole body flexural stiffness of teleost fish over ranges of deformations which are typical of swimming and maneuvering. Teleost scales are thin and relatively flexible, so they can accommodate large flexural deformations. This finding is in contrast to the bulkier ganoid scales which were shown in previous reports to have a profound impact of global flexural deformations and swimming in fish like gar or Polypterus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Response of pig skin to fractionated radiation doses

International Nuclear Information System (INIS)

Wiernik, G.; Hopewell, J.W.; Patterson, T.J.S.; Young, C.M.A.; Foster, J.L.

1977-01-01

The individual components of a fractionated course of irradiation treatment have been considered separately. Methods of accurate measurement of individual parameters has brought to light different interpretations of the observations. Reasons are given for the necessity of having a radiobiological model which has a direct relevance to the clinical situation. Results are reported for fractionated regimes of irradiation in which the dose has been varied above and below normal tissue tolerance which has been equated with clinical skin necrosis. The components of the acute skin reaction, erythema, pigmentation and desquamation have been analysed separately and their contribution as a method of measurement assessed. Initially, the range of numerical scores attributed to erythema did not reach the scores attributed to necrosis but we now believe that radiation damage expressed as erythema can move directly into necrosis without passing through desquamation. Desquamation, on the other hand, only became a useful parameter at higher dose levels; it has also been shown to be a component associated with skin breakdown. Pigmentation showed no dose response at the dose levels employed in our experiments and it is our belief that this is due to this system being fully saturated under these circumstances. Measurement of the late radiation reaction in the skin has been considered in detail and our results have been expressed by comparing the relative lengths of irradiated and control fields in the same pig. From these findings iso-effect graphs have been constructed and time and fractionation factors have been derived. (author)

Increased Sensitization to Mold Allergens Measured by Intradermal Skin Testing following Hurricanes.

Science.gov (United States)

Saporta, Diego; Hurst, David

2017-01-01

Objective . To report on changes in sensitivity to mold allergens determined by changes in intradermal skin testing reactivity, after exposure to two severe hurricanes. Methods . A random, retrospective allergy charts review divided into 2 groups of 100 patients each: Group A, patients tested between 2003 and 2010 prior to hurricanes, and Group B, patients tested in 2014 and 2015 following hurricanes. Reactivity to eighteen molds was determined by intradermal skin testing. Test results, age, and respiratory symptoms were recorded. Chi-square test determined reactivity/sensitivity differences between groups. Results . Posthurricane patients had 34.6 times more positive results ( p hurricanes ( p hurricanes ( p hurricanes. This supports climatologists' hypothesis that environmental changes resulting from hurricanes can be a health risk as reflected in increased allergic sensitivities and symptoms and has significant implications for physicians treating patients from affected areas.

Differential skin test reactivity to pollens in pollen food allergy syndrome versus allergic rhinitis.

Science.gov (United States)

Ta, Von; Scott, David R; Chin, William K; Wineinger, Nathan E; Kelso, John M; White, Andrew A

2015-01-01

Pollen food allergy syndrome (PFAS), also called oral allergy syndrome, is a form of food allergy in which uncooked foods cause allergic symptoms generally limited to the oral mucosa. It occurs in a subset of patients with pollen allergy, although not all patients have prominent rhinitis symptoms. PFAS is related to antigenic similarity between the pollen and food allergen. The size of skin test reactions in a group of subjects with pollen sensitivity with PFAS was compared with a group of subjects who were pollen sensitive and without PFAS. Self-reported rhinitis symptoms between the two groups were compared to identify if symptom severity differed. Twenty subjects with PFAS and 20 subjects with seasonal allergic rhinitis without PFAS were enrolled in the study. All the subjects underwent standard skin-prick testing to a panel of common allergens, including select fresh fruits and vegetables. The subjects completed a Mini Rhinoconjunctivitis Quality of Life Questionnaire as part of their clinical evaluation. The subjects with PFAS and those without PFAS were compared statistically. The subjects with PFAS had significantly larger-sized skin-prick test results specific to pollens (p PFAS reported milder nasal symptoms in relation to pollen skin test result size when compared with allergic rhinitis controls without PFAS. Our study outlined basic differences between two seemingly similar patient groups with a particularly striking discordance between skin test result sizes and rhinitis symptoms. This discordance should be explored further to increase mechanistic understanding of allergen cross-reactivity in PFAS.

Studies of biaxial mechanical properties and nonlinear finite element modeling of skin.

Science.gov (United States)

Shang, Xituan; Yen, Michael R T; Gaber, M Waleed

2010-06-01

The objective of this research is to conduct mechanical property studies of skin from two individual but potentially connected aspects. One is to determine the mechanical properties of the skin experimentally by biaxial tests, and the other is to use the finite element method to model the skin properties. Dynamic biaxial tests were performed on 16 pieces of abdominal skin specimen from rats. Typical biaxial stress-strain responses show that skin possesses anisotropy, nonlinearity and hysteresis. To describe the stress-strain relationship in forms of strain energy function, the material constants of each specimen were obtained and the results show a high correlation between theory and experiments. Based on the experimental results, a finite element model of skin was built to model the skin's special properties including anisotropy and nonlinearity. This model was based on Arruda and Boyce's eight-chain model and Bischoff et al.'s finite element model of skin. The simulation results show that the isotropic, nonlinear eight-chain model could predict the skin's anisotropic and nonlinear responses to biaxial loading by the presence of an anisotropic prestress state.

Skin test reactivity among Danish children measured 15 years apart

DEFF Research Database (Denmark)

Thomsen, SF; Ulrik, Charlotte Suppli; Porsbjerg, C

2006-01-01

BACKGROUND: Knowledge of secular trends in the prevalence of allergy among children stems in large part from questionnaire surveys, whereas repeated cross-sectional studies using objective markers of atopic sensitization are sparse. OBJECTIVES: To investigate whether the prevalence of skin prick...... (n = 527) and the second in 2001 (n = 480). Skin test reactivity to nine common aeroallergens was measured at both occasions. RESULTS: The prevalence of positive SPT to at least one allergen decreased from 24.1% in 1986 to 18.9% in 2001, (p = 0.05). We found a declining prevalence of sensitization...

Skin test concentrations for systemically administered drugs -- an ENDA/EAACI Drug Allergy Interest Group position paper

NARCIS (Netherlands)

Brockow, K.; Garvey, L. H.; Aberer, W.; Atanaskovic-Markovic, M.; Barbaud, A.; Bilo, M. B.; Bircher, A.; Blanca, M.; Bonadonna, B.; Campi, P.; Castro, E.; Cernadas, J. R.; Chiriac, A. M.; Demoly, P.; Grosber, M.; Gooi, J.; Lombardo, C.; Mertes, P. M.; Mosbech, H.; Nasser, S.; Pagani, M.; Ring, J.; Romano, A.; Scherer, K.; Schnyder, B.; Testi, S.; Torres, M.; Trautmann, A.; Terreehorst, I.

2013-01-01

Skin tests are of paramount importance for the evaluation of drug hypersensitivity reactions. Drug skin tests are often not carried out because of lack of concise information on specific test concentrations. The diagnosis of drug allergy is often based on history alone, which is an unreliable

[Characteristics of allergic conjunctivitis with positive skin prick test].

Science.gov (United States)

Yang, S; Jiang, Y; Jin, Y M; Zhang, J Y; Li, Y

2017-09-11

Objective: To observe the clinical characteristics of allergic conjunctivitis, and the correlations with skin prick test results. Methods: A retrospective study. Forty patients with positive skin prick test result were included. Patients underwent an ophthalmologic examination to identify their primary presenting signs and symptoms. The allergy types were divided into 5 groups. All dates were analyzed for the dependence, normality and homogeneity of variance. Chi-square test, Mann-Whitney U test, Kruskal-Wallis H test and Spearman correlation analysis were performed accordingly. Results: Among 40 patients, 18(45.0%) had a clinical diagnosis of seasonal allergic conjunctivitis, 14(35.0%) had perennial allergic conjunctivitis, 5(12.5%) had vernal keratoconjunctivitis, and 2(5.0%) had atopic keratoconjunctivits, and 1(2.5%) had giant papillary conjunctivitis. There was no significant difference in the number of symptoms and signs score among different types of allergic conjunctivitis, the score of itching and hyperemia had a positive relationship with the number of positive allergens ( r =0.74, Ptest of the allergen, the more symptoms and signs encountered in terms of severity. Conclusion: Seasonal allergic conjunctivitis was the most prevalent disorder, the most important clinical characteristics of allergic conjunctivitis are itching and conjunctival congestion, the main allergens are dust and pollens, patients may be sensitive to multiple allergens. (Chin J Ophthalmol, 2017, 53: 689-693) .

Effect of skin temperature on cutaneous vasodilator response to the β-adrenergic agonist isoproterenol

OpenAIRE

Hodges, Gary J.; Kellogg, Dean L.; Johnson, John M.

2015-01-01

The vascular response to local skin cooling is dependent in part on a cold-induced translocation of α2C-receptors and an increased α-adrenoreceptor function. To discover whether β-adrenergic function might contribute, we examined whether β-receptor sensitivity to the β-agonist isoproterenol was affected by local skin temperature. In seven healthy volunteers, skin blood flow was measured from the forearm by laser-Doppler flowmetry and blood pressure was measured by finger photoplethysmography....

Changes in skin barrier during treatment with systemic alitretinoin: focus on skin susceptibility and stratum corneum ceramides

DEFF Research Database (Denmark)

Jungersted, J.M.; Høgh, Julie Kaae; Hellgren, Lars

2010-01-01

) was performed on the volar forearm and evaluated by trans-epidermal water loss (TEWL), erythema, and a cyanoacrylate skin sample was obtained for lipid analysis. We found no significant changes in response to SLS irritation as evaluated by TEWL and erythema, after treatment with alitretinoin for 2 months......Alitretinoin is a new drug for systemic treatment of chronic hand eczema. Previous functional tests of skin topically treated with retinoids have indicated impaired skin barrier function, but no data are available on barrier parameters after systemic alitretinoin treatment. To investigate...

Exposure to 4100K fluorescent light elicits sex specific transcriptional responses in Xiphophorus maculatus skin.

Science.gov (United States)

Boswell, William T; Boswell, Mikki; Walter, Dylan J; Navarro, Kaela L; Chang, Jordan; Lu, Yuan; Savage, Markita G; Shen, Jianjun; Walter, Ronald B

2018-06-01

It has been reported that exposure to artificial light may affect oxygen intake, heart rate, absorption of vitamins and minerals, and behavioral responses in humans. We have reported specific gene expression responses in the skin of Xiphophorus fish after exposure to ultraviolet light (UV), as well as, both broad spectrum and narrow waveband visible light. In regard to fluorescent light (FL), we have shown that male X. maculatus exposed to 4100K FL (i.e. "cool white") rapidly suppress transcription of many genes involved with DNA replication and repair, chromosomal segregation, and cell cycle progression in skin. We have also detailed sex specific transcriptional responses of Xiphophorus skin after exposure to UVB. However, investigation of gender differences in global gene expression response after exposure to 4100K FL has not been reported, despite common use of this FL source for residential, commercial, and animal facility illumination. Here, we compare RNA-Seq results analyzed to assess changes in the global transcription profiles of female and male X. maculatus skin in response to 4100K FL exposure. Our results suggest 4100K FL exposure incites a sex-biased genetic response including up-modulation of inflammation in females and down modulation of DNA repair/replication in males. In addition, we identify clusters of genes that become oppositely modulated in males and females after FL exposure that are principally involved in cell death and cell proliferation. Copyright © 2017 Elsevier Inc. All rights reserved.

Antibiotic-induced immediate type hypersensitivity is a risk factor for positive allergy skin tests for neuromuscular blocking agents.

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Hagau, Natalia; Gherman, Nadia; Cocis, Mihaela; Petrisor, Cristina

2016-01-01

Skin tests for neuromuscular blocking agents (NMBAs) are not currently recommended for the general population undergoing general anaesthesia. In a previous study we have reported a high incidence of positive allergy tests for NMBAs in patients with a positive history of non-anaesthetic drug allergy, a larger prospective study being needed to confirm those preliminary results. The objective of this study was to compare the skin tests results for patients with a positive history of antibiotic-induced immediate type hypersensitivity reactions to those of controls without drug allergies. Ninety eight patients with previous antibiotic hypersensitivity and 72 controls were prospectively included. Skin tests were performed for atracurium, pancuronium, rocuronium, and suxamethonium. We found 65 positive skin tests from the 392 tests performed in patients with a positive history of antibiotic hypersensitivity (1 6.58%) and 23 positive skin tests from the 288 performed in controls (7.98%), the two incidences showing significant statistical difference (p = 0.0011). The relative risk for having a positive skin test for NMBAs for patients versus controls was 1.77 (1.15-2.76). For atracurium, skin tests were more often positive in patients with a positive history of antibiotic hypersensitivity versus controls (p = 0.02). For pancuronium, rocuronium and suxamethonium the statistical difference was not attained (p-values 0.08 for pancuronium, 0.23 for rocuronium, and 0.26 for suxamethonium). Patients with a positive history of antibiotic hypersensitivity seem to have a higher incidence of positive skin tests for NMBAs. They might represent a group at higher risk for developing intraoperative anaphylaxis compared to the general population. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Development of an in vitro skin sensitization test based on ROS production in THP-1 cells.

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Saito, Kazutoshi; Miyazawa, Masaaki; Nukada, Yuko; Sakaguchi, Hitoshi; Nishiyama, Naohiro

2013-03-01

Recently, it has been reported that reactive oxygen species (ROS) produced by contact allergens can affect dendritic cell migration and contact hypersensitivity. The aim of the present study was to develop a new in vitro assay that could predict the skin sensitizing potential of chemicals by measuring ROS production in THP-1 (human monocytic leukemia cell line) cells. THP-1 cells were pre-loaded with a ROS sensitive fluorescent dye, 5-(and 6-)-chloromethyl-2', 7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H2DCFDA), for 15min, then incubated with test chemicals for 30min. The fluorescence intensity was measured by flow cytometry. For the skin sensitizers, 25 out of 30 induced over a 2-fold ROS production at more than 90% of cell viability. In contrast, increases were only seen in 4 out of 20 non-sensitizers. The overall accuracy for the local lymph node assay (LLNA) was 82% for 50 chemicals tested. A correlation was found between the estimated concentration showing 2-fold ROS production in the ROS assay and the EC3 values (estimated concentration required to induce positive response) of the LLNA. These results indicated that the THP-1 cell-based ROS assay was a rapid and highly sensitive detection system able to predict skin sensitizing potentials and potency of chemicals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Skin mechanical properties and modeling: A review.

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Joodaki, Hamed; Panzer, Matthew B

2018-04-01

The mechanical properties of the skin are important for various applications. Numerous tests have been conducted to characterize the mechanical behavior of this tissue, and this article presents a review on different experimental methods used. A discussion on the general mechanical behavior of the skin, including nonlinearity, viscoelasticity, anisotropy, loading history dependency, failure properties, and aging effects, is presented. Finally, commonly used constitutive models for simulating the mechanical response of skin are discussed in the context of representing the empirically observed behavior.

Degree of skin denervation and its correlation to objective thermal sensory test in leprosy patients.

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Ismael Alves Rodrigues Júnior

Full Text Available BACKGROUND: Leprosy is an infectious disease affecting skin and peripheral nerves resulting in increased morbidity and physical deformities. Early diagnosis provides opportune treatment and reduces its complications, relying fundamentally on the demonstration of impaired sensation in suggestive cutaneous lesions. The loss of tactile sensitivity in the lesions is preceded by the loss of thermal sensitivity, stressing the importance of the thermal test in the suspicious lesions approach. The gold-standard method for the assessment of thermal sensitivity is the quantitative sensory test (QST. Morphological study may be an alternative approach to access the thin nerve fibers responsible for thermal sensitivity transduction. The few studies reported in leprosy patients pointed out a rarefaction of thin dermo-epidermal fibers in lesions, but used semi-quantitative evaluation methods. METHODOLOGY/PRINCIPAL FINDINGS: This work aimed to study the correlation between the degree of thermal sensitivity impairment measured by QST and the degree of denervation in leprosy skin lesions, evaluated by immunohistochemistry anti-PGP 9.5 and morphometry. Twenty-two patients were included. There were significant differences in skin thermal thresholds among lesions and contralateral skin (cold, warm, cold induced pain and heat induced pain. The mean reduction in the density of intraepidermal and subepidermal fibers in lesions was 79.5% (SD = 19.6 and 80.8% (SD = 24.9, respectively. CONCLUSIONS/SIGNIFICANCE: We observed a good correlation between intraepidermal and subepidermal fibers deficit, but no correlation between these variables and those accounting for the degree of impairment in thermal thresholds, since the thin fibers rarefaction was homogeneously intense in all patients, regardless of the degree of sensory deficit. We believe that the homogeneously intense denervation in leprosy lesions should be objective of further investigations focused on its

Cultured skin microbiota attracts malaria mosquitoes

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Takken Willem

2009-12-01

Full Text Available Abstract Background Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours. It is hypothesized that host attractiveness and selection of An. gambiae is affected by the species composition, density, and metabolic activity of the skin microbiota. A study is presented in which the production and constituency of volatile organic compounds (VOCs by human skin microbiota is examined and the behavioural responses of An. gambiae to VOCs from skin microbiota are investigated. Methods Blood agar plates incubated with skin microbiota from human feet or with a reference strain of Staphylococcus epidermidis were tested for their attractiveness to An. gambiae in olfactometer bioassays and indoor trapping experiments. Entrained air collected from blood agar plates incubated with natural skin microbiota or with S. epidermidis were analysed using GC-MS. A synthetic blend of the compounds identified was tested for its attractiveness to An. gambiae. Behavioural data were analysed by a χ2-test and GLM. GC-MS results were analysed by fitting an exponential regression line to test the effect of the concentration of bacteria. Results More An. gambiae were caught with blood agar plates incubated with skin bacteria than with sterile blood agar plates, with a significant effect of incubation time and dilution of the skin microbiota. When bacteria from the feet of four other volunteers were tested, similar effects were found. Fourteen putative attractants were found in the headspace of the skin bacteria. A synthetic blend of 10 of these was attractive to An. gambiae. Conclusions The discovery that volatiles produced by human skin microorganisms in vitro mediate An. gambiae host-seeking behaviour creates new opportunities for the

Safety and skin delayed-type hypersensitivity response in vervet monkeys immunized with Leishmania donovani sonicate antigen delivered with adjuvants

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Joshua M. Mutiso

2012-02-01

Full Text Available In this study, we report on the safety and skin delayed-type hypersensitivity (DTH, responses of the Leishmania donovani whole cell sonicate antigen delivered in conjunction with alum-BCG (AlBCG, Montanide ISA 720 (MISA or Monophosphoryl lipid A (MPLA in groups of vervet monkeys. Following three intradermal injections of the inoculums on days 0, 28 and 42, safety and DTH responses were assessed. Preliminary tumor necrosis factor alpha (TNF-α and interferon gamma (IFN-γ levels were also measured and these were compared with DTH. Only those animals immunized with alum-BCG reacted adversely to the inoculum by producing ulcerative erythematous skin indurations. Non-parametric analysis of variance followed by a post-test showed significantly higher DTH responses in the MISA+Ag group compared with other immunized groups (p < 0.001. The MPLA+Ag group indicated significantly lower DTH responses to the sonicate antigen compared with the AlBCG+Ag group. There was a significant correlation between the DTH and cytokine responses (p < 0.0001. Based on this study we conclude that Leishmania donovani sonicate antigen containing MISA 720 is safe and is associated with a strong DTH reaction following immunization.

Characterisation of the clinical and activated T cell response to repeat delayed-type hypersensitivity skin challenges in human subjects, with KLH and PPD, as a potential model to test T cell-targeted therapies.

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Belson, Alexandra; Schmidt, Tim; Fernando, Disala; Hardes, Kelly; Scott, Nicola; Brett, Sara; Clark, Deborah; Oliveira, João Joaquim; Davis, Bill; McHugh, Simon; Stone, John

2016-05-01

To characterise the delayed-type hypersensitivity (DTH) skin reaction to repeated challenges of keyhole limpet hemocyanin (KLH) and tuberculin purified protein derivative (PPD) in healthy volunteers, as a potential model to test T cell-targeted investigational agents. Forty-nine subjects received either KLH, PPD, or PBS repeat skin challenges, and clinical assessments including induration, erythema and Laser Doppler Imaging. Skin biopsies or suction blisters were taken after challenge to investigate the cellular infiltrate of the challenge site, the T cell activation status, as determined by LAG-3 expression, and, specifically for the blister, the concentrations of inflammatory cytokines. Point estimates, estimates of variation and corresponding 95% confidence intervals were constructed for each type of challenge and timepoint. The DTH response could be measured at 48 and 120 h post-KLH and PPD challenge with induration, erythema and Laser Doppler Imaging, with 48 h post-challenge demonstrating the peak of the response. PPD was well tolerated in subjects after multiple challenges, however, a significant number of KLH-treated subjects demonstrated an injection site reaction 6-7 days following the SC injection. PPD demonstrated a boost effect on the second challenge as measured by increased induration, where as this was not noted consistently for KLH. Compared to unchallenged and PBS control-injected skin, increased T cell numbers were detected in the challenge site by both the skin suction blister and biopsy technique, at either time point following KLH or PPD challenge. Use of the T cell activation marker LAG-3 demonstrated the activated phenotype of these cells. In skin blisters, higher numbers of LAG-3+ T cells were detected at 48 h post-challenge, whereas in the biopsies, similar numbers of LAG-3+ cells were observed at both 48 and 120 h. Analysis of blister T cell subpopulations revealed some differences in phenotypes between the time points and between the CD4

The Effects of Low Dose Irradiation on Inflammatory Response Proteins in a 3D Reconstituted Human Skin Tissue Model

Energy Technology Data Exchange (ETDEWEB)

Varnum, Susan M.; Springer, David L.; Chaffee, Mary E.; Lien, Katie A.; Webb-Robertson, Bobbie-Jo M.; Waters, Katrina M.; Sacksteder, Colette A.

2012-12-01

Skin responses to moderate and high doses of ionizing radiation include the induction of DNA repair, apoptosis, and stress response pathways. Additionally, numerous studies indicate that radiation exposure leads to inflammatory responses in skin cells and tissue. However, the inflammatory response of skin tissue to low dose radiation (<10 cGy) is poorly understood. In order to address this, we have utilized a reconstituted human skin tissue model (MatTek EpiDerm FT) and assessed changes in 23 cytokines twenty-four and forty eight hours following treatment of skin with either 3 or 10 cGy low-dose of radiation. Three cytokines, IFN-γ, IL-2, MIP-1α, were significantly altered in response to low dose radiation. In contrast, seven cytokines were significantly altered in response to a high radiation dose of 200 cGy (IL-2, IL-10, IL-13, IFN-γ, MIP-1α, TNF α, and VEGF) or the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (G-CSF, GM-CSF, IL-1α, IL-8, MIP-1α, MIP-1β, RANTES). Additionally, radiation induced inflammation appears to have a distinct cytokine response relative to the non-radiation induced stressor, TPA. Overall, these results indicate that there are subtle changes in the inflammatory protein levels following exposure to low dose radiation and this response is a sub-set of what is seen following a high dose in a human skin tissue model.

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).

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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.

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

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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.

A rare subset of skin-tropic regulatory T cells expressing Il10/Gzmb inhibits the cutaneous immune response.

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Ikebuchi, Ryoyo; Teraguchi, Shunsuke; Vandenbon, Alexis; Honda, Tetsuya; Shand, Francis H W; Nakanishi, Yasutaka; Watanabe, Takeshi; Tomura, Michio

2016-10-19

Foxp3 + regulatory T cells (Tregs) migrating from the skin to the draining lymph node (dLN) have a strong immunosuppressive effect on the cutaneous immune response. However, the subpopulations responsible for their inhibitory function remain unclear. We investigated single-cell gene expression heterogeneity in Tregs from the dLN of inflamed skin in a contact hypersensitivity model. The immunosuppressive genes Ctla4 and Tgfb1 were expressed in the majority of Tregs. Although Il10-expressing Tregs were rare, unexpectedly, the majority of Il10-expressing Tregs co-expressed Gzmb and displayed Th1-skewing. Single-cell profiling revealed that CD43 + CCR5 + Tregs represented the main subset within the Il10/Gzmb-expressing cell population in the dLN. Moreover, CD43 + CCR5 + CXCR3 - Tregs expressed skin-tropic chemokine receptors, were preferentially retained in inflamed skin and downregulated the cutaneous immune response. The identification of a rare Treg subset co-expressing multiple immunosuppressive molecules and having tissue-remaining capacity offers a novel strategy for the control of skin inflammatory responses.

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

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Pengcheng Liu

2016-06-01

Full Text Available 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.

Effect of skin barrier disruption on immune responses to topically applied cross-reacting material, CRM(197), of diphtheria toxin.

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Godefroy, S; Peyre, M; Garcia, N; Muller, S; Sesardic, D; Partidos, C D

2005-08-01

The high accessibility of the skin and the presence of immunocompetent cells in the epidermis makes this surface an attractive route for needle-free administration of vaccines. However, the lining of the skin by the stratum corneum is a major obstacle to vaccine delivery. In this study we examined the effect of skin barrier disruption on the immune responses to the cross-reacting material CRM(197), a nontoxic mutant of diphtheria toxin (DTx) that is considered as a vaccine candidate. Application of CRM(197), together with cholera toxin (CT), onto the tape-stripped skin of mice elicited antibody responses that had anti-DTx neutralizing activity. Vaccine delivery onto mildly ablated skin or intact skin did not elicit any detectable anti-CRM(197) antibodies. Mice immunized with CRM(197) alone onto the tape-stripped skin mounted a vigorous antigen-specific proliferative response. In contrast, the induction of cellular immunity after CRM(197) deposition onto mildly ablated or intact skin was adjuvant dependent. Furthermore, epidermal cells were activated and underwent apoptosis that was more pronounced when the stratum corneum was removed by tape stripping. Overall, these findings highlight the potential for transcutaneous delivery of CRM(197) and establish a correlation between the degree of barrier disruption and levels of antigen-specific immune responses. Moreover, these results provide the first evidence that the development of a transcutaneous immunization strategy for diphtheria, based on simple and practical methods to disrupt the skin barrier, is feasible.

Enhanced immune responses by skin vaccination with influenza subunit vaccine in young hosts.

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Koutsonanos, Dimitrios G; Esser, E Stein; McMaster, Sean R; Kalluri, Priya; Lee, Jeong-Woo; Prausnitz, Mark R; Skountzou, Ioanna; Denning, Timothy L; Kohlmeier, Jacob E; Compans, Richard W

2015-09-08

Skin has gained substantial attention as a vaccine target organ due to its immunological properties, which include a high density of professional antigen presenting cells (APCs). Previous studies have demonstrated the effectiveness of this vaccination route not only in animal models but also in adults. Young children represent a population group that is at high risk from influenza infection. As a result, this group could benefit significantly from influenza vaccine delivery approaches through the skin and the improved immune response it can induce. In this study, we compared the immune responses in young BALB/c mice upon skin delivery of influenza vaccine with vaccination by the conventional intramuscular route. Young mice that received 5 μg of H1N1 A/Ca/07/09 influenza subunit vaccine using MN demonstrated an improved serum antibody response (IgG1 and IgG2a) when compared to the young IM group, accompanied by higher numbers of influenza-specific antibody secreting cells (ASCs) in the bone marrow. In addition, we observed increased activation of follicular helper T cells and formation of germinal centers in the regional lymph nodes in the MN immunized group, rapid clearance of the virus from their lungs as well as complete survival, compared with partial protection observed in the IM-vaccinated group. Our results support the hypothesis that influenza vaccine delivery through the skin would be beneficial for protecting the high-risk young population from influenza infection. Copyright © 2015. Published by Elsevier Ltd.

Characterisation of human skin models - stability, metabolic capacity and comparative investigations in percutaneous absorption

OpenAIRE

Schreiber, Sylvia

2010-01-01

In recent years, the demand for alternative test methods in safety assessment of cosmetics, risk assessment of chemicals, and testing of pharmaceuticals was increasingly included in the EU directives. Thereby, alternative test methods for the determination of percutaneous absorption should achieve a more reliable in vivo prediction of the response of human skin than animal skin. Even though freshly excised human skin is considered as a preferred test matrix its routine use is often difficult ...

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

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Anki Malmborg

2017-01-01

Full Text Available 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.

The response of human skin commensal bacteria as a reflection of UV radiation: UV-B decreases porphyrin production.

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Yanhan Wang

Full Text Available Recent global radiation fears reflect the urgent need for a new modality that can simply determine if people are in a radiation risk of developing cancer and other illnesses. Ultraviolet (UV radiation has been thought to be the major risk factor for most skin cancers. Although various biomarkers derived from the responses of human cells have been revealed, detection of these biomarkers is cumbersome, probably requires taking live human tissues, and varies significantly depending on human immune status. Here we hypothesize that the reaction of Propionibacterium acnes (P. acnes, a human resident skin commensal, to UV radiation can serve as early surrogate markers for radiation risk because the bacteria are immediately responsive to radiation. In addition, the bacteria can be readily accessible and exposed to the same field of radiation as human body. To test our hypothesis, P. acnes was exposed to UV-B radiation. The production of porphyrins in P. acnes was significantly reduced with increasing doses of UV-B. The porphyrin reduction can be detected in both P. acnes and human skin bacterial isolates. Exposure of UV-B to P. acnes- inoculated mice led to a significant decrease in porphyrin production in a single colony of P. acnes and simultaneously induced the formation of cyclobutane pyrimidine dimers (CPD in the epidermal layers of mouse skin. Mass spectrometric analysis via a linear trap quadrupole (LTQ-Orbitrap XL showed that five peptides including an internal peptide (THLPTGIVVSCQNER of a peptide chain release factor 2 (RF2 were oxidized by UV-B. Seven peptides including three internal peptides of 60 kDa chaperonin 1 were de-oxidized by UV-B. When compared to UV-B, gamma radiation also decreased the porphyrin production of P. acnes in a dose-dependent manner, but induced a different signature of protein oxidation/de-oxidation. We highlight that uncovering response of skin microbiome to radiation will facilitate the development of pre

The response of human skin commensal bacteria as a reflection of UV radiation: UV-B decreases porphyrin production.

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Wang, Yanhan; Zhu, Wenhong; Shu, Muya; Jiang, Yong; Gallo, Richard L; Liu, Yu-Tsueng; Huang, Chun-Ming

2012-01-01

Recent global radiation fears reflect the urgent need for a new modality that can simply determine if people are in a radiation risk of developing cancer and other illnesses. Ultraviolet (UV) radiation has been thought to be the major risk factor for most skin cancers. Although various biomarkers derived from the responses of human cells have been revealed, detection of these biomarkers is cumbersome, probably requires taking live human tissues, and varies significantly depending on human immune status. Here we hypothesize that the reaction of Propionibacterium acnes (P. acnes), a human resident skin commensal, to UV radiation can serve as early surrogate markers for radiation risk because the bacteria are immediately responsive to radiation. In addition, the bacteria can be readily accessible and exposed to the same field of radiation as human body. To test our hypothesis, P. acnes was exposed to UV-B radiation. The production of porphyrins in P. acnes was significantly reduced with increasing doses of UV-B. The porphyrin reduction can be detected in both P. acnes and human skin bacterial isolates. Exposure of UV-B to P. acnes- inoculated mice led to a significant decrease in porphyrin production in a single colony of P. acnes and simultaneously induced the formation of cyclobutane pyrimidine dimers (CPD) in the epidermal layers of mouse skin. Mass spectrometric analysis via a linear trap quadrupole (LTQ)-Orbitrap XL showed that five peptides including an internal peptide (THLPTGIVVSCQNER) of a peptide chain release factor 2 (RF2) were oxidized by UV-B. Seven peptides including three internal peptides of 60 kDa chaperonin 1 were de-oxidized by UV-B. When compared to UV-B, gamma radiation also decreased the porphyrin production of P. acnes in a dose-dependent manner, but induced a different signature of protein oxidation/de-oxidation. We highlight that uncovering response of skin microbiome to radiation will facilitate the development of pre-symptomatic diagnosis

Quantification of Tissue Trauma following Insulin Pen Needle Insertions in Skin

DEFF Research Database (Denmark)

Jensen, Casper Bo; Larsen, Rasmus; Vestergaard, Jacob Schack

Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop a computa......Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop...... a computational method to quantify tissue trauma based on skin bleeding and immune response. Method: Two common sized pen needles of 28G (0.36mm) and 32G (0.23mm) were inserted into skin of sedated LYD pigs prior to termination. Four pigs were included and a total of 32 randomized needle insertions were conducted...... diameter. Conclusion: A computational and quantitative method has been developed to assess tissue trauma following insulin pen needle insertions. Application of the method is tested by conduction of a needle diameter study. The obtained quantitative measures of tissue trauma correlate positively to needle...

Development and psychometric testing of the 'Motivation and Self-Efficacy in Early Detection of Skin Lesions' index.

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Dyson, Judith; Cowdell, Fiona

2014-12-01

To develop and psychometrically test the Motivation and Self-Efficacy in Early Detection of Skin Lesions Index. Skin cancer is the most frequently diagnosed cancer worldwide. The primary strategy used to prevent skin cancer is promotion of sun avoidance and the use of sun protection. However, despite costly and extensive campaigns, cases of skin cancer continue to increase. If found and treated early, skin cancer is curable. Early detection is, therefore, very important. The study was conducted in 2013. Instrument Development. A literature review and a survey identified barriers (factors that hinder) and levers (factors that help) to skin self-examination. These were categorized according to a the Theoretical Domains Framework and this formed the basis of an instrument, which was tested for validity and reliability using confirmatory factor analysis and Cronbach's alpha respectively. A five-factor 20-item instrument was used that tested well for reliability and construct validity. Test-retest reliability was good for all items and domains. The five factors were: (i) Outcome expectancies; (ii) Intention; (iii) Self-efficacy; (iv) Social influences; (v) Memory. The Motivation and Self-Efficacy in Early Detection of Skin Lesions Index provides a reliable and valid method of assessing barriers and levers to skin self-examination. The next step is to design a theory-based intervention that can be tailored according to individual determinants to behaviour change identified by this instrument. © 2014 John Wiley & Sons Ltd.

Development, standardization and testing of a bacterial wound infection model based on ex vivo human skin.

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Christoph Schaudinn

Full Text Available Current research on wound infections is primarily conducted on animal models, which limits direct transferability of these studies to humans. Some of these limitations can be overcome by using-otherwise discarded-skin from cosmetic surgeries. Superficial wounds are induced in fresh ex vivo skin, followed by intradermal injection of Pseudomonas aeruginosa under the wound. Subsequently, the infected skin is incubated for 20 hours at 37°C and the CFU/wound are determined. Within 20 hours, the bacteria count increased from 107 to 109 bacteria per wound, while microscopy revealed a dense bacterial community in the collagen network of the upper wound layers as well as numerous bacteria scattered in the dermis. At the same time, IL-1alpha and IL-1beta amounts increased in all infected wounds, while-due to bacteria-induced cell lysis-the IL-6 and IL-8 concentrations rose only in the uninfected samples. High-dosage ciprofloxacin treatment resulted in a decisive decrease in bacteria, but consistently failed to eradicate all bacteria. The main benefits of the ex vivo wound model are the use of healthy human skin, a quantifiable bacterial infection, a measureable donor-dependent immune response and a good repeatability of the results. These properties turn the ex vivo wound model into a valuable tool to examine the mechanisms of host-pathogen interactions and to test antimicrobial agents.

Comparison of sensitivity of quantiferon-tb gold test and tuberculin skin test in active pulmonary tuberculosis

International Nuclear Information System (INIS)

Khalil, K.F.; Ambreen, A.; Butt, T.

2013-01-01

Objective: To compare the sensitivity of tuberculin skin test (TST) and quantiFERON-TB gold test (QFT-G) in active pulmonary tuberculosis. Study Design: Analytical study. Place and Duration of Study: Department of Pulmonology, Fauji Foundation Hospital, Rawalpindi, from July 2011 to January 2012. Methodology: QuantiFERON-TB gold test (QFT-G) was evaluated and compared it with tuberculin skin test (TST) in 50 cases of active pulmonary tuberculosis, in whom tuberculous infection was suspected on clinical, radiological and microbiological grounds. Sensitivity was determined against positive growth for Mycobacterium tuberculosis. Results: Out of 50 cases, 43 were females and 7 were males. The mean age was 41.84 A+- 19.03 years. Sensitivity of QFT-G was 80% while that of TST was 28%. Conclusion: QFT-G has much higher sensitivity than TST for active pulmonary tuberculosis. It is unaffected by prior BCG administration and prior exposure to atypical mycobacteria. A positive QFT-G result can be an adjunct to diagnosis in patients having clinical and radiological data compatible with pulmonary tuberculosis. (author)

A study on the frictional response of reptilian shed skin

International Nuclear Information System (INIS)

Abdel-Aal, H A; Vargiolu, R; Zahouani, H; Mansori, M El

2011-01-01

Deterministic surfaces are constructs of which profile, topography and textures are integral to the function of the system they enclose. They are designed to yield a predetermined tribological response. Developing such entities relies on controlling the structure of the rubbing interface so that, not only the surface is of optimized topography, but also is able to self-adjust its tribological behaviour according to the evolution of sliding conditions. In seeking inspirations for such designs, many engineers are turning toward the biological world to study the construction and behaviour of bio-analogues, and to probe the role surface topography assumes in conditioning of frictional response. That is how a bio-analogue can self-adjust its tribological response to adapt to habitat constraints. From a tribological point of view, Squamate Reptiles, offer diverse examples where surface texturing, submicron and nano-scale features, achieves frictional regulation. In this paper, we study the frictional response of shed skin obtained from a snake (Python regius). The study employed a specially designed tribo-acoustic probe capable of measuring the coefficient of friction and detecting the acoustical behavior of the skin in vivo. The results confirm the anisotropy of the frictional response of snakes. The coefficient of friction depends on the direction of sliding: the value in forward motion is lower than that in the backward direction. Diagonal and side winding motion induces a different value of the friction coefficient. We discuss the origin of such a phenomenon in relation to surface texturing and study the energy constraints, implied by anisotropic friction, on the motion of the reptile.

A study on the frictional response of reptilian shed skin

Energy Technology Data Exchange (ETDEWEB)

Abdel-Aal, H A [Arts et Metier ParisTech, Rue Saint Dominique BP 508, 51006 Chalons-en-Champagne (France); Vargiolu, R; Zahouani, H [Laboratoire de Tribology et Dynamique des Systemes, UMR CNRS 5513, ENI Saint Etienne - Ecole Centrale de Lyon -36 Avenue Guy de Collongue, 69131 Ecully cedex. France (France); Mansori, M El, E-mail: Hisham.abdel-aal@ensam.eu [Ecole Nationale Superieure d' Arts et Metiers, 2, cours des Arts et Metiers - 13617 Aix en Provence cedex 1 (France)

2011-08-19

Deterministic surfaces are constructs of which profile, topography and textures are integral to the function of the system they enclose. They are designed to yield a predetermined tribological response. Developing such entities relies on controlling the structure of the rubbing interface so that, not only the surface is of optimized topography, but also is able to self-adjust its tribological behaviour according to the evolution of sliding conditions. In seeking inspirations for such designs, many engineers are turning toward the biological world to study the construction and behaviour of bio-analogues, and to probe the role surface topography assumes in conditioning of frictional response. That is how a bio-analogue can self-adjust its tribological response to adapt to habitat constraints. From a tribological point of view, Squamate Reptiles, offer diverse examples where surface texturing, submicron and nano-scale features, achieves frictional regulation. In this paper, we study the frictional response of shed skin obtained from a snake (Python regius). The study employed a specially designed tribo-acoustic probe capable of measuring the coefficient of friction and detecting the acoustical behavior of the skin in vivo. The results confirm the anisotropy of the frictional response of snakes. The coefficient of friction depends on the direction of sliding: the value in forward motion is lower than that in the backward direction. Diagonal and side winding motion induces a different value of the friction coefficient. We discuss the origin of such a phenomenon in relation to surface texturing and study the energy constraints, implied by anisotropic friction, on the motion of the reptile.

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.

Science.gov (United States)

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.

A Study on the Effects of Sympathetic Skin Response Parameters in Diagnosis of Fibromyalgia Using Artificial Neural Networks.

Science.gov (United States)

Ozkan, Ozhan; Yildiz, Murat; Arslan, Evren; Yildiz, Sedat; Bilgin, Suleyman; Akkus, Selami; Koyuncuoglu, Hasan R; Koklukaya, Etem

2016-03-01

Fibromyalgia syndrome (FMS), usually observed commonly in females over age 30, is a rheumatic disease accompanied by extensive chronic pain. In the diagnosis of the disease non-objective psychological tests and physiological tests and laboratory test results are evaluated and clinical experiences stand out. However, these tests are insufficient in differentiating FMS with similar diseases that demonstrate symptoms of extensive pain. Thus, objective tests that would help the diagnosis are needed. This study analyzes the effect of sympathetic skin response (SSR) parameters on the auxiliary tests used in FMS diagnosis, the laboratory tests and physiological tests. The study was conducted in Suleyman Demirel University, Faculty of Medicine, Physical Medicine and Rehabilitation Clinic in Turkey with 60 patients diagnosed with FMS for the first time and a control group of 30 healthy individuals. In the study all participants underwent laboratory tests (blood tests), certain physiological tests (pulsation, skin temperature, respiration) and SSR measurements. The test data and SSR parameters obtained were classified using artificial neural network (ANN). Finally, in the ANN framework, where only laboratory and physiological test results were used as input, a simulation result of 96.51 % was obtained, which demonstrated diagnostic accuracy. This data, with the addition of SSR parameter values obtained increased to 97.67 %. This result including SSR parameters - meaning a higher diagnostic accuracy - demonstrated that SSR could be a new auxillary diagnostic method that could be used in the diagnosis of FMS.

De-labelling self-reported penicillin allergy within the emergency department through the use of skin tests and oral drug provocation testing.

Science.gov (United States)

Marwood, Joseph; Aguirrebarrena, Gonzalo; Kerr, Stephen; Welch, Susan A; Rimmer, Janet

2017-10-01

Self-reported penicillin allergy is common among patients attending the ED, but is a poor predictor of true immunoglobulin E-mediated hypersensitivity to penicillin. We hypothesise that with a combination of skin testing and drug provocation testing, selected patients can be safely de-labelled of their allergy. This prospective study enrolled a sample of patients presenting to an urban academic ED between 2011 and 2016 with a self-reported allergy to penicillin. Standardised skin prick and intradermal testing with amoxicillin and both major and minor determinants of penicillin was performed in the department. If negative, testing was followed by a graded oral challenge of amoxicillin over 9 days. The primary end point was the allergy status of participants at the end of the study. A total of 100 patients (mean age 42; standard deviation 14 years; 54% women) completed the testing. Of these, 81% (95% confidence interval 71.9-88.2) showed no hypersensitivity to penicillin and were labelled non-allergic. The majority (16/19) of allergies were confirmed by skin testing, with three suspected allergies detected by the oral challenge. Women were more likely than men to have a true penicillin allergy, with odds ratio of 4.0 (95% confidence interval 1.23-13.2). There were no serious adverse events. Selected patients in the ED who self-report an allergy to penicillin can be safely tested there for penicillin allergy, using skin tests and oral drug provocation testing. This testing allows a significant de-labelling of penicillin allergy, with the majority of these patients able to tolerate penicillin without incident. © 2017 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Test-Anchored Vibration Response Predictions for an Acoustically Energized Curved Orthogrid Panel with Mounted Components

Science.gov (United States)

Frady, Gregory P.; Duvall, Lowery D.; Fulcher, Clay W. G.; Laverde, Bruce T.; Hunt, Ronald A.

2011-01-01

rich body of vibroacoustic test data was recently generated at Marshall Space Flight Center for component-loaded curved orthogrid panels typical of launch vehicle skin structures. The test data were used to anchor computational predictions of a variety of spatially distributed responses including acceleration, strain and component interface force. Transfer functions relating the responses to the input pressure field were generated from finite element based modal solutions and test-derived damping estimates. A diffuse acoustic field model was applied to correlate the measured input sound pressures across the energized panel. This application quantifies the ability to quickly and accurately predict a variety of responses to acoustically energized skin panels with mounted components. Favorable comparisons between the measured and predicted responses were established. The validated models were used to examine vibration response sensitivities to relevant modeling parameters such as pressure patch density, mesh density, weight of the mounted component and model form. Convergence metrics include spectral densities and cumulative root-mean squared (RMS) functions for acceleration, velocity, displacement, strain and interface force. Minimum frequencies for response convergence were established as well as recommendations for modeling techniques, particularly in the early stages of a component design when accurate structural vibration requirements are needed relatively quickly. The results were compared with long-established guidelines for modeling accuracy of component-loaded panels. A theoretical basis for the Response/Pressure Transfer Function (RPTF) approach provides insight into trends observed in the response predictions and confirmed in the test data. The software developed for the RPTF method allows easy replacement of the diffuse acoustic field with other pressure fields such as a turbulent boundary layer (TBL) model suitable for vehicle ascent. Structural responses

GALEN skin test study III: Minimum battery of test inhalent allergens needed in epidemiological studies in patients

NARCIS (Netherlands)

Bousquet, P.-J.; Burbach, G.; Heinzerling, L. M.; Edenharter, G.; Bachert, C.; Bindslev-Jensen, C.; Bonini, S.; Bousquet-Rouanet, L.; Demoly, P.; Bresciani, M.; Bruno, A.; Gjomarkaj, M.; Canonica, G. W.; Darsow, U.; Durham, S.; Fokkens, W. J.; Giavi, S.; Gramiccioni, C.; Papadopoulos, N. G.; Haahtela, T.; Kowalski, M. L.; Magyar, P.; Muraközi, G.; Orosz, M.; Röhnelt, C.; Stingl, G.; Todo-Bom, A.; von Mutius, E.; Wiesner, A.; Wöhrl, S.; Bousquet, J.; Zuberbier, T.

2009-01-01

Background: The number of allergens to be tested in order to identify sensitized patients is important in order to have the most cost-effective approach in epidemiological studies. Objective: To define the minimal number and the type of skin prick test (SPT) allergens required to identify a patient

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

Science.gov (United States)

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. 2008 FRAME.

The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

International Nuclear Information System (INIS)

Wondergem, J.; Haveman, J.

1983-01-01

The effect of previous x-irradiation on the response to hyperthermia (44 0 C), x-irradiation, and irradiation combined with hyperthermia (43 0 C or 44 0 C) was studied in mouse foot skin. Irradiation of mice feet 90 days before, with 20 Gy, increased the subsequent response to heat alone, or combined with irradiation, as well as to irradiation alone. It had little effect on the thermal enhancement ratios for both acute and late skin reactions. Memory of the previous irradiation treatment could be masked when the temperature of the subsequent heat treatment alone, or combined with irradiation, was 44 0 C. Priming heat treatment induced resistance to a subsequent heat treatment and to a subsequent combined irradiation-heat treatment in normal as well as previously irradiated skin. When late skin reaction was considered, a larger 'memory' of the previous irradiation treatment was always evident, compared to acute skin reaction: the 'remembered' dose in the late skin reaction was about twice the 'remembered' dose in the acute reaction. (U.K.)

The relation between constitutional skin color and photosensitivity estimated from UV-induced erythema and pigmentation dose-response curves

NARCIS (Netherlands)

Westerhof, W.; Estevez-Uscanga, O.; Meens, J.; Kammeyer, A.; Durocq, M.; Cario, I.

1990-01-01

In 54 healthy volunteers we assessed predictors of sensitivity to ultraviolet (UV) light, including Fitzpatrick's sun reactive skin types and constitutional skin color, and compared these with one another and with responses of the skin to UV irradiation, as determined experimentally by a minimal

In vitro and in vivo characterization of hazelnut skin prick test extracts

NARCIS (Netherlands)

Akkerdaas, Jaap H.; Wensing, Marjolein; Knulst, André C.; Aalberse, Rob C.; Hefle, Susan L.; van Ree, Ronald

2003-01-01

RATIONALE: Hazelnut allergy ranks among the most frequently observed food allergies. Clinical symptoms range from the oral allergy syndrome to life threatening anaphylaxis. Diagnosis of hazelnut allergy partially relies on in vivo testing by means of skin prick testing (SPT). The aim of this study

Responsiveness of the Spanish Version of the “Skin Cancer Index”

Directory of Open Access Journals (Sweden)

M. de Troya-Martín

2016-01-01

Full Text Available Background. Skin Cancer Index (SCI is a specific questionnaire measuring health related quality of life (HRQL in patients with cervicofacial non-melanoma skin cancer (CFNMSC. The original scale has recently been adapted and validated into Spanish. Objectives. Evaluate the responsiveness of the Spanish version of SCI. Methods. Patients with CFNMSC candidate for surgical treatment were administered the questionnaire at time of diagnostic (t0, 7 days after surgery (t1, and 5 months after surgery (t2. The scale and subscales scores (C1: social/appearance, C2: emotional were then evaluated. Differences between t0-t1, t1-t2, and t0-t2 were determined and a gender-and-age segmented analysis was performed. Results. 88 patients, 54.8% male, mean age 62.5 years, completed the study. Differences between t0-t1 and t1-t2 scores were statistically significant (p<0.05. The lowest values were found at time of diagnosis and postsurgery. Women and patients under 65 years showed the lowest values at the three times. Limitations. Concrete geographic and cultural area. Clinical and histological variables are not analysed. Conclusions. Our results confirm responsiveness of the Spanish version of the SCI. Further development of the instrument in Spanish-speaking countries and populations will make it possible to extend worldwide research and knowledge horizons on skin cancer.

Skin Cancer Screening

Science.gov (United States)

... Genetics of Skin Cancer Skin Cancer Screening Research Skin Cancer Screening (PDQ®)–Patient Version What is screening? ... These are called diagnostic tests . General Information About Skin Cancer Key Points Skin cancer is a disease ...

Pattern Of Skin Prick Allergy Test Results In Enugu | Mgbor ...

African Journals Online (AJOL)

In this study we report on pattern of allergy prick skin test results found among atopic patients attending the department of otorhinolargngology of the University of Nigeria Teaching Hospital Enugu and Hansa Clinics, Enugu and propose ways of minimizing the exposure of the population to allergens. Material and method

Differential immune response of congenic mice to ultraviolet-treated major histocompatibility complex class II-incompatible skin grafts

International Nuclear Information System (INIS)

Vermeer, B.J.; Santerse, B.; Van De Kerckhove, B.A.; Schothorst, A.A.; Claas, F.H.

1988-01-01

The influence of ultraviolet (UVB) irradiation on the survival of H-2 class II-disparate skin grafts was studied in congenic mouse strains. Isolated skin was UVB irradiated in vitro at a dose of 40 mJ/cm 2 from both sides to remove Ia immunogenicity. Immediately after irradiation the skin was transplanted onto the flank of allogeneic mice. When B10.AQR grafts were transplanted onto B10.T(6R) recipients, a significant prolongation of the survival time was observed, while 50% of the UVB-treated grafts were not rejected at all. However, in the opposite direction--i.e., B10.T(6R) grafts onto B10.AQR recipients, no significant prolongation of the survival was observed. To test whether this effect was due to a difference in susceptibility of the donor skin to UVB irradiation or to a different immune response in the recipients, (B10.T(6R) x B10.AQR) grafts were transplanted onto the parent strains. Similar results were obtained, in that UVB-treated grafts did not show a prolonged survival in B10.AQR recipients, whereas a significant prolongation (50% of the grafts survived more than 100 days) was observed in B10.T(6R) recipients. UVB-treated (B10.T(6R) x B10.AQR)F1 grafts were also transplanted onto (B10.T(6R) x C57B1/10)F1, (B10.AQR x C57B1/10)F1, (B10.T(6R) x Balb/c)F1 and (B10.AQR x Balb/c)F1 recipients--but in none of these combinations was a prolonged survival time observed. These data suggest that, in contrast to all in vitro experiments, the abrogation of the immune response by UVB treatment of the stimulator cells is, in vivo, not a general phenomenon. The genetic constitution of the responder mice seems to play an important role in determining whether or not an immune response takes place

Influence of hydration and experimental length scale on themechanical response of human skin in vivo, using optical coherence tomography

NARCIS (Netherlands)

Hendriks, F.M.; Brokken, D.; Oomens, C.W.J.; Baaijens, F.P.T.

2004-01-01

Human skin is a complex tissue consisting of different layers. To gain better insight into the mechanical behaviour of different skin layers, the mechanical response was studied with experiments of various length scales. Also, the influence of (superficial) hydration on the mechanical response is

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

Science.gov (United States)

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

2012-08-01

Patients suffering from postherpetic neuralgia often complain about hypo- or hypersensation in the affected dermatome. The loss of thermal sensitivity has been demonstrated by quantitative sensory testing as being associated with small-fiber (Aδ- and C-fiber) deafferentation. We aimed to compare laser stimulation (radiant heat) to thermode stimulation (contact heat) with regard to their sensitivity and specificity to detect thermal sensory deficits related to small-fiber dysfunction in postherpetic neuralgia. We contrasted detection rate of laser stimuli with 5 thermal parameters (thresholds of cold/warm detection, cold/heat pain, and sensory limen) of quantitative sensory testing. Sixteen patients diagnosed with unilateral postherpetic neuralgia and 16 age- and gender-matched healthy control subjects were tested. Quantitative sensory testing and laser stimulation of tiny skin areas were performed in the neuralgia-affected skin and in the contralateral homologue of the neuralgia-free body side. Across the 5 thermal parameters of thermode stimulation, only one parameter (warm detection threshold) revealed sensory abnormalities (thermal hypoesthesia to warm stimuli) in the neuralgia-affected skin area of patients but not in the contralateral area, as compared to the control group. In contrast, patients perceived significantly less laser stimuli both in the affected skin and in the contralateral skin compared to controls. Overall, laser stimulation proved more sensitive and specific in detecting thermal sensory abnormalities in the neuralgia-affected skin, as well as in the control skin, than any single thermal parameter of thermode stimulation. Thus, laser stimulation of tiny skin areas might be a useful diagnostic tool for small-fiber dysfunction. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Skin care products can aggravate epidermal function: studies in a murine model suggest a pathogenic role in sensitive skin.

Science.gov (United States)

Li, Zhengxiao; Hu, Lizhi; Elias, Peter M; Man, Mao-Qiang

2018-02-01

Sensitive skin is defined as a spectrum of unpleasant sensations in response to a variety of stimuli. However, only some skin care products provoke cutaneous symptoms in individuals with sensitive skin. Hence, it would be useful to identify products that could provoke cutaneous symptoms in individuals with sensitive skin. To assess whether vehicles, as well as certain branded skin care products, can alter epidermal function following topical applications to normal mouse skin. Following topical applications of individual vehicle or skin care product to C57BL/6J mice twice daily for 4 days, transepidermal water loss (TEWL) rates, stratum corneum (SC) hydration and skin surface pH were measured on treated versus untreated mouse skin with an MPA5 device and pH 900 pH meter. Our results show that all tested products induced abnormalities in epidermal functions of varying severity, including elevations in TEWL and skin surface pH, and reduced SC hydration. Our results suggest that mice can serve as a predictive model that could be used to evaluate the potential safety of skin care products in humans with sensitive skin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Skin barrier properties in patients with recessive X-linked ichthyosis

DEFF Research Database (Denmark)

Johansen, J D; Ramsing, D; Vejlsgaard, G

1995-01-01

increased in controls compared to ichthyosis patients, when evaluated by TEWL. When evaluated by erythema index a statistically significant increase in redness was found in controls, but not in ichthyosis patients. Electrical capacitance, reflecting skin hydration, was significantly reduced in RXLI patients......Patients with X-linked recessive ichthyosis (RXLI) were studied as a model of the effect of disturbed epidermal lipid composition on skin barrier function. Thirteen patients with RXLI and 15 age- and sex-matched controls were patch-tested with sodium lauryl sulphate (SLS) 0.5% for 24 h. Basal skin...... properties and skin response to SLS were studied by measurement of transepidermal water loss (TEWL), electrical capacitance and erythema index. No statistically significant difference in basal TEWL was found between the two groups. The skin response to SLS was found to be statistically significantly...

Dose-response models for the radiation-induction of skin tumours in mice

International Nuclear Information System (INIS)

Papworth, D.G.; Hulse, E.V.

1983-01-01

Extensive data on radiation-induced skin tumours in mice were examined using 8 models, all based on the concept that incidences of radiation-induced tumours depend on a combination of two radiation effects: a tumour induction process and the loss of reproductive integrity by the potential tumour cells. Models with and without a threshold were used, in spite of theoretical objections to threshold models. No model fitted well both the epidermal and the dermal tumour data and models which proved to be statistically satisfactory for some of the data were rejected for biological reasons. It is concluded that, for skin tumours, dose-response curves depending on a combination of cancer induction and loss of cellular reproductive integrity are distorted by some special, relatively radio-resistant, factor which we have previously postulated as being involved in radiation skin carcinogenesis. (author)

Environment and the skin

International Nuclear Information System (INIS)

Suskind, R.R.

1990-01-01

The skin is an important organ of defense adaptation and a portal of entry for xenobiotics. It is vulnerable to physical, chemical, and biologic agents and capable of expressing responses to these agents in a variety of pathologic patterns. These patterns are characterized by morphologic and functional features which are elicited by careful examination and test procedures. Cutaneous cancer may result from exposure to nonionizing as well as ionizing radiation, to specific identifiable chemical hazards, and may be enhanced by trauma. Cutaneous hazards of chemical sources are largely found in the workplace and among consumer products, including drugs and toilet goods. Environmental skin diseases and injuries are preventable. Prior to use assessment for safety and for possible risks from exposure to an agent, product, or process is of primary importance in the prevention and control of environmental skin disease and injury

Preoperative ultraviolet B inflammation in skin

DEFF Research Database (Denmark)

Lunn, T H; Dawes, J M; Denk, F

2018-01-01

BACKGROUND: Neuroimmune interactions play a vital role in many of the most common pain conditions, such as arthritis. There have been many attempts to derive clinically predictive information from an individual's inflammatory response in order to gauge subsequent pain perception. OBJECTIVES: Here......, we wanted to test whether this effort could be enhanced and complemented by the use of a model system which takes into account the function of not just circulating, but also tissue-resident immune cells: ultraviolet B (UVB) irradiation of the skin. METHODS: We conducted psychophysical...... in the skin might predict the degree of a patient's neuro-immune response and the extent of their postoperative pain after total knee arthroplasty....

Impact of changed legislation on skin tests: the present and future

NARCIS (Netherlands)

Klimek, Ludger; Hoffmann, Hans Jürgen; Kugler, Alexa; Muraro, Antonella; Hellings, Peter W.

2016-01-01

To discuss the impact of current European Union regulations on the availability of commercially available skin test allergens in European member states. European Union legislations now define diagnostic allergens to be medicine requiring market authorization of every individual diagnostic allergen

A simple in chemico method for testing skin sensitizing potential of chemicals using small endogenous molecules.

Science.gov (United States)

Nepal, Mahesh Raj; Shakya, Rajina; Kang, Mi Jeong; Jeong, Tae Cheon

2018-06-01

Among many of the validated methods for testing skin sensitization, direct peptide reactivity assay (DPRA) employs no cells or animals. Although no immune cells are involved in this assay, it reliably predicts the skin sensitization potential of a chemical in chemico. Herein, a new method was developed using endogenous small-molecular-weight compounds, cysteamine and glutathione, rather than synthetic peptides, to differentiate skin sensitizers from non-sensitizers with an accuracy as high as DPRA. The percent depletion of cysteamine and glutathione by test chemicals was measured by an HPLC equipped with a PDA detector. To detect small-size molecules, such as cysteamine and glutathione, a derivatization by 4-(4-dimethylaminophenylazo) benzenesulfonyl chloride (DABS-Cl) was employed prior to the HPLC analysis. Following test method optimization, a cut-off criterion of 7.14% depletion was applied to differentiate skin sensitizers from non-sensitizers in combination of the ratio of 1:25 for cysteamine:test chemical with 1:50 for glutathione:test chemical for the best predictivity among various single or combination conditions. Although overlapping HPLC peaks could not be fully resolved for some test chemicals, high levels of sensitivity (100.0%), specificity (81.8%), and accuracy (93.3%) were obtained for 30 chemicals tested, which were comparable or better than those achieved with DPRA. Copyright © 2018 Elsevier B.V. All rights reserved.

The sensitization potential of sunscreen after ablative fractional skin resurfacing using modified human repeated insult patch test.

Science.gov (United States)

Boonchai, Waranya; Sathaworawong, Angkana; Wongpraparut, Chanisada; Wanitphakdeedecha, Rungsima

2015-10-01

Ablative fractional skin resurfacing has become popular and proven to be useful in treating scars, photoaging and wrinkles. Although post-inflammatory hyperpigmentation (PIH) is the most common complication especially in dark-skinned patients like Asian. Several modalities have been used to overcome the PIH. To determine the sensitization potential of sunscreen applied immediately after ablative fractional skin resurfacing. Sixty volunteers were recruited. Of these 30 subjects were from previous ablative fractional skin resurfacing study who applied broad-spectrum sunscreen containing anti-inflammatory agent starting on the first day after resurfacing and another 30 non-resurfacing subjects had applied the same sunscreen on the intact skin. All subjects were patch/photopatch tested for sensitization study by using modified human repeated insult patch test (HRIPT). There were significantly higher sensitization rate of UV-filter, octocrylene and the sunscreen in resurfacing group than in non-resurfacing group. Early application of sunscreen after ablative fractional skin resurfacing has increased the incidence of sensitization potential of sunscreen. The sunscreen is recommended to start using from D3 after fractional ablative skin resurfacing to ensure the complete recovery of skin barrier and minimize the risk of sensitization.

Determination of the axial and circumferential mechanical properties of the skin tissue using experimental testing and constitutive modeling.

Science.gov (United States)

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.

Caffeine ameliorates radiation-induced skin reactions in mice but does not influence tumour radiation response

Energy Technology Data Exchange (ETDEWEB)

Hebbar, S.A.; Mitra, A.K.; George, K.C.; Verma, N.C. [Radiation Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)]. E-mail: ncverma@apsara.barc.ernet.in

2002-03-01

Intramuscular administration of caffeine at a dose of 80 mg kg{sup -1} body weight to the gastrocnemius muscles of Swiss mice 5 min prior to local irradiation (35 Gy) of the leg delayed the progression of radiation-induced skin reactions in such animals. While 90% epilation with reddening of the skin was noted in animals treated with radiation alone, animals pretreated with caffeine suffered only partial hair loss with slight reddening of the skin on the 16th and 20th days post-irradiation. Beyond the 28th day, damage scores in irradiated feet for both the groups were similar (score 3) and remained unchanged until the 32nd day and then decreased and disappeared completely in both treatment groups by the 40th day after irradiation. In addition, the effect of caffeine on the radiation response of a mouse fibrosarcoma was investigated. Results showed that intratumoral administration of caffeine at a dose of 80 mg kg{sup -1} body weight 5 min prior to local exposure of tumours to 10 Gy of {sup 60}Co {gamma}-rays did not influence the response of tumours to radiation. The present study thus showed that although caffeine ameliorated radiation-induced skin reactions in the mouse leg, it did not affect the tumour radiation response, indicating its potential application in cancer radiotherapy. (author)

Bee Venom Pharmacopuncture Responses According to Sasang Constitution and Gender

Directory of Open Access Journals (Sweden)

Kim Chaeweon

2013-12-01

Full Text Available Objectives: The current study was performed to compare the bee venom pharmacopuncture skin test reactions among groups with different sexes and Sasang constitutions. Methods: Between July 2012 and June 2013, all 76 patients who underwent bee venom pharmacopuncture skin tests and Sasang constitution diagnoses at Oriental Medicine Hospital of Sangji University were included in this study. The skin test was performed on the patient’s forearm intracutaneously with 0.05 ml of sweet bee venom (SBV on their first visit. If the patients showed a positive response, the test was discontinued. On the other hand, if the patient showed a negative response, the test was performed on the opposite forearm intracutaneously with 0.05 ml of bee venom pharmacopuncture 25% on the next day or the next visit. Three groups were made to compare the differences in the bee venom pharmacopuncture skin tests according to sexual difference and Sasang constitution: group A showed a positive response to SBV, group B showed a positive response to bee venom pharmacopuncture 25%, and group C showed a negative response on all bee venom pharmacopuncture skin tests. Fisher’s exact test was performed to evaluate the differences statistically. Results: The results of the bee venom pharmacopuncture skin tests showed no significant differences according to Sasang constitution (P = 0.300 or sexual difference (P = 0.163. Conclusion: No significant differences on the results of bee venom pharmacopuncture skin tests were observed according to two factors, Sasang constitution and the sexual difference.

A SKIN TEST FOR DETECTING GROUP C HEMOLYTIC STREPTOCOCCAL INFECTION CAUSING EPIZOOTIC LYMPHADENITIS IN GUINEA PIGS

Science.gov (United States)

Moen, Johannes K.

1936-01-01

1. A skin test with a crude bacterial extract prepared from group C (Lancefield) hemolytic streptococci was used as a means of detecting possible carriers of the streptococcus causing epizootic lymphadenitis in guinea pigs. A positive test similar to a positive tuberculin reaction was considered presumptive evidence of present or recent infection with this streptococcus. 2. 20 positive reactors were found in 330 supposedly normal guinea pigs. 3. 195 negatively reacting animals were used as a breeding stock which yielded 1,296 progeny over a period of 15 months. None of the breeding stock or their progeny showed evidence of spontaneous lymphadenitis. Skin tests of 100 of the progeny were all negative. 4. The use of this skin test as a means of obtaining guinea pig breeding stock free of the streptococcus causing spontaneous lymphadenitis is suggested. PMID:19870552

Study of Laser Reflectivity on Skin

International Nuclear Information System (INIS)

Oidor-Garcia, J. J. J.; Trevino-Palacios, C. G.

2008-01-01

The response to the light on the skin can be manifested as temperature increase or creation of biochemical byproducts, in which further studies are required to asset the light effect. This response changes the average response over time and can produce discrepancies between similar studies. In this work we present a Low Level Laser Therapy (LLLT) study with feedback. We study the time response reflectivity of a 980 nm laser diode of 25 mW modulated at frequencies close to 40 kHz and detect the reflected light on a silicon photodiode, finding no direct correlation between different test points or individuals, while finding reproducible responses within the same individual and test point

Histological and Immunological Description of the Leishmanin Skin Test in Ibizan Hounds.

Science.gov (United States)

Ordeix, L; Silva, J E Dos S; Llull, J; Quirola, P; Montserrat-Sangrà, S; Martínez-Orellana, P; Solano-Gallego, L

2018-01-01

The leishmanin skin test (LST), a delayed-type hypersensitivity (DTH) reaction to Leishmania infantum, can specifically identify dogs that have made a cell-mediated immune response to L. infantum infection. The Ibizan hound appears to be more resistant to L. infantum infection than other breeds of dog. The aim of this study was to describe the histological and immunohistochemical changes induced by the LST in Ibizan hounds living in an area highly endemic for leishmaniosis. The majority of dogs were apparently healthy, lacked serum antibody to L. infantum and blood parasitaemia, but had marked specific interferon gamma production after in-vitro blood stimulation with L. infantum. Leishmanin (3 × 10 8 killed promastigotes of L. infantum/ml) was injected intradermally and biopsy samples were obtained from a positive reaction at 72 h from nine Ibizan hounds. A moderate to intense, perivascular to interstitial dermatitis and panniculitis characterized the inflammatory response at the injection site. In addition, three samples had diffuse inflammation in the deep dermis and panniculus. Oedema and necrosis were present in the deep dermis and panniculus. Congestion and haemorrhage were observed in five biopsies. T lymphocytes (CD3 + ) and large mononuclear cells (lysozyme - ) were the most prevalent cells. CD3 + cells were significantly more numerous than CD20 + B cells and lysozyme + cells. B cells were sparsely distributed, especially in the deep dermis and panniculus. Rare neutrophils and macrophages (lysozyme + ) were observed with few eosinophils. Toll-like receptor (TLR)-2 protein was expressed in large mononuclear cells mainly located in the superficial dermis. Leishmania immunohistochemistry was negative and quantitative polymerase chain reaction was positive in all cases. The intradermal injection of killed L. infantum promastigotes in Ibizan hounds causes similar histological and immunohistochemical findings to those described for human subjects and are

Advanced Development of Leishmania Topical Skin Test Antigen

Science.gov (United States)

2012-09-28

was discarded. The lysate was then heated in a water bath for 30 minutes at 60°C. The material was cooled to 10 °C, poured into sterile centrifuge...followed to assess the effectiveness of the cleaning and sanitization procedures. The filling, capping and assembly of final containers occurred in Class...40 and 80 µg doses per 0.1 mL. For all skin tests, 0.1 mL was injected intradermally into the volar surface of the forearm . Final LtSTA Report for

Positive Skin Test or Specific IgE to Penicillin Does Not Reliably Predict Penicillin Allergy.

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Tannert, Line Kring; Mortz, Charlotte Gotthard; Skov, Per Stahl; Bindslev-Jensen, Carsten

According to guidelines, patients are diagnosed with penicillin allergy if skin test (ST) result or specific IgE (s-IgE) to penicillin is positive. However, the true sensitivity and specificity of these tests are presently not known. To investigate the clinical relevance of a positive ST result and positive s-IgE and to study the reproducibility of ST and s-IgE. A sample of convenience of 25 patients with positive penicillin ST results, antipenicillin s-IgE results, or both was challenged with their culprit penicillin. Further 19 patients were not challenged, but deemed allergic on the basis of a recent anaphylactic reaction or delayed reactions to skin testing. Another sample of convenience of 18 patients, 17 overlapping with the 25 challenged, with initial skin testing and s-IgE (median, 25; range, 3-121), months earlier (T -1 ), was repeat skin tested and had s-IgE measured (T 0 ), and then skin tested and had s-IgE measured 4 weeks later (T 1 ). Only 9 (36%) of 25 were challenge positive. There was an increased probability of being penicillin allergic if both ST result and s-IgE were positive at T 0 . Positive ST result or positive s-IgE alone did not predict penicillin allergy. Among the 18 patients repeatedly tested, 46.2% (12 of 25) of positive ST results at T -1 were reproducibly positive at T 0 . For s-IgE, 54.2% (14 of 24) positive measurements were still positive at T 0 and 7 converted to positive at T 1 . The best predictor for a clinically significant (IgE-mediated) penicillin allergy is a combination of a positive case history with simultaneous positive ST result and s-IgE or a positive challenge result. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Skin-transmitted pathogens and the heebie jeebies: evidence for a subclass of disgust stimuli that evoke a qualitatively unique emotional response.

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Blake, Khandis R; Yih, Jennifer; Zhao, Kun; Sung, Billy; Harmon-Jones, Cindy

2017-09-01

Skin-transmitted pathogens have threatened humans since ancient times. We investigated whether skin-transmitted pathogens were a subclass of disgust stimuli that evoked an emotional response that was related to, but distinct from, disgust and fear. We labelled this response "the heebie jeebies". In Study 1, coding of 76 participants' experiences of disgust, fear, and the heebie jeebies showed that the heebie jeebies was elicited by unique stimuli which produced skin-crawling sensations and an urge to protect the skin. In Experiment 2,350 participants' responses to skin-transmitted pathogen, fear-inducing, and disgust-inducing vignettes showed that the vignettes elicited sensations and urges which loaded onto heebie jeebies, fear, and disgust factors, respectively. Experiment 3 largely replicated findings from Experiment 2 using video stimuli (178 participants). Results are consistent with the notion that skin-transmitted pathogens are a subclass of disgust stimuli which motivate behaviours that are functionally consistent with disgust yet qualitatively distinct.

Fibroblast radiosensitivity versus acute and late normal skin responses in patients treated for breast cancer

International Nuclear Information System (INIS)

Brock, William A.; Tucker, Susan L.; Geara, Fady B.; Wike, Jennifer; Peters, Lester J.; Turesson, Ingela; Nyman, Jan

1995-01-01

Purpose/Objective: To determine if the radiosensitivity of normal human skin fibroblasts, measured in early passage cultures, is significantly correlated with the degree of acute or late normal skin damage in patients treated for breast cancer with radiotherapy. Methods and Materials: In the 1970s, a series of breast cancer patients was treated at the Department of Oncology in Gothenburg, Sweden with postoperative irradiation to the parasternal region. Patients were treated bilaterally using different fractionation schedules and doses to the right and left fields. Peak acute reactions were scored on a six-point scale, and skin erythema was measured by reflectance spectrophotometry. Telangiectasia was graded over time on a six-point scale. In April 1992, two small skin biopsies were obtained from 22 patients in two treatment groups (i.e., four dose-fractionation schedules) and, using either delayed or immediate plating, fibroblast radiosensitivity was measured in early passage cultures by clonogenic survival, after high and low dose-rate irradiations. Survival at 2.0 Gy (SF2) was calculated from complete survival curves. Results: To test assay reproducibility, SF2 values derived from paired biopsies of the same patient (12 cases) were compared. A reasonably good correlation (p = 0.075) was obtained for SF2s determined by high dose-rate irradiations with immediate plating, but not for delayed plating or low dose-rate treatments. The median coefficient of variation in the replicate SF2s after high dose-rate treatment and immediate plating was 13%, suggesting that the poor correlation in paired SF2 values is due to the magnitude of the uncertainty in SF2 relative to the overall spread in SF2 values between patients (CV = 28%). Individual SF2 values and averaged values from patients with data from two biopsies were compared with the acute and late clinical reactions. A significant negative correlation was found between SF2 and relative clinical response, but only when

Characterization of guinea pig T cell responses elicited after EP-assisted delivery of DNA vaccines to the skin.

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Schultheis, Katherine; Schaefer, Hubert; Yung, Bryan S; Oh, Janet; Muthumani, Karuppiah; Humeau, Laurent; Broderick, Kate E; Smith, Trevor R F

2017-01-03

The skin is an ideal target tissue for vaccine delivery for a number of reasons. It is highly accessible, and most importantly, enriched in professional antigen presenting cells. Possessing strong similarities to human skin physiology and displaying a defined epidermis, the guinea pig is an appropriate model to study epidermal delivery of vaccine. However, whilst we have characterized the humoral responses in the guinea pig associated with skin vaccine protocols we have yet to investigate the T cell responses. In response to this inadequacy, we developed an IFN-γ ELISpot assay to characterize the cellular immune response in the peripheral blood of guinea pigs. Using a nucleoprotein (NP) influenza pDNA vaccination regimen, we characterized host T cell responses. After delivery of the DNA vaccine to the guinea pig epidermis we detected robust and rapid T cell responses. The levels of IFN-γ spot-forming units averaged approximately 5000 per million cells after two immunizations. These responses were broad in that multiple regions across the NP antigen elicited a T cell response. Interestingly, we identified a number of NP immunodominant T cell epitopes to be conserved across an outbred guinea pig population, a phenomenon which was also observed after immunization with a RSV DNA vaccine. We believe this data enhances our understanding of the cellular immune response elicited to a vaccine in guinea pigs, and globally, will advance the use of this model for vaccine development, especially those targeting skin as a delivery site. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Optical coherence tomography applied to tests of skin care products in humans--a case study.

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Vasquez-Pinto, L M C; Maldonado, E P; Raele, M P; Amaral, M M; de Freitas, A Z

2015-02-01

When evaluating skin care products for human skin, quantitative test methods need to be simple, precise and reliable. Optical coherence tomography (OCT), provides high-resolution sectional images of translucent materials to a depth of a few millimeters, a technique usually applied to medical measurements in ophthalmology and dermatology. This study aimed to demonstrate the application of OCT as the main technique for monitoring changes in skin topography during tests of a wrinkle-reduction product in humans. We used a commercial OCT apparatus to perform clinical examinations of skin roughness in treated and non-treated sites in the periorbital region of thirty human voluntaries who were using an anti-aging product commercially available: Natura Chronos® Flavonóides de Passiflora 45+ FPS15, from Natura Cosméticos, Brazil. Measurements were performed days 0, 7, 14 and 28 of treatment. Equipment and software allowed real-time recording of skin roughness parameters and wrinkle depths. The OCT measurements have allowed the monitoring of changes in skin roughness, which have shown reduction in treated sites around 10%. The obtained depth distributions also indicate reduction in the occurrence of wrinkles deeper than 170 μm. The verified results are consistent with those typically obtained after successful treatment with modern anti-aging products. By using the OCT technique, it was possible to quantify changes in skin roughness and in the distribution of depths of skin wrinkles, with adequate sensitivity. OCT imaging allows the direct visualization of the skin topography with resolution of micrometers, a reliable and interactive tool for clinical use. Therefore, for the first time, we demonstrated the use of OCT technique to verify the efficacy of cosmetic products in real time. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[IFN-gamma enzyme-linked immunospot assay versus PPD tuberculin skin test in the diagnosis of tuberculous epididymitis].

Science.gov (United States)

Huang, Hao; Yang, Xi-Fei; Deng, Qun-Yi; Li, Bing; Liu, Guo-Hui; Zhang, Jie-Yun; Yang, Da-Fei

2012-06-01

To explore the potential application of IFN-gamma enzyme-linked immunospot (ELISPOT) assay in the diagnosis of tuberculous epididymitis (TE) by comparing ELISPOT assay with the traditional purified protein derivative (PPD) tuberculin skin test. We examined 13 TE patients using an in-house ELISPOT kit, another 11 TE patients by PPD skin testing, and 57 healthy male volunteers by parallel test with both the methods. Twelve (92.3%) of the 13 TE cases were positive on ELISPOT assay, and 10 (90.9%) of the 11 TE cases positive on PPD skin test, with no statistically significant differences between the two groups (P > 0.05). Among the 57 healthy male volunteers, 8 (14.0%) were positive on ELISPOT, and 28 (49.1%) positive on PPD test, the latter significantly higher than the former (P PPD test in the examination of tuberculous epididymitis. As for specificity, ELISPOT assay seems better than PPD test in differentiating tuberculous epididymitis patients from healthy males.

A tan in a test tube - in vitro models for investigating ultraviolet radiation-induced damage in skin.

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Fernandez, Tara L; Dawson, Rebecca A; Van Lonkhuyzen, Derek R; Kimlin, Michael G; Upton, Zee

2012-06-01

Presently, global rates of skin cancers induced by ultraviolet radiation (UVR) exposure are on the rise. In view of this, current knowledge gaps in the biology of photocarcinogenesis and skin cancer progression urgently need to be addressed. One factor that has limited skin cancer research has been the need for a reproducible and physiologically-relevant model able to represent the complexity of human skin. This review outlines the main currently-used in vitro models of UVR-induced skin damage. This includes the use of conventional two-dimensional cell culture techniques and the major animal models that have been employed in photobiology and photocarcinogenesis research. Additionally, the progression towards the use of cultured skin explants and tissue-engineered skin constructs, and their utility as models of native skin's responses to UVR are described. The inherent advantages and disadvantages of these in vitro systems are also discussed. © 2012 John Wiley & Sons A/S.

Mechanisms regulating skin immunity and inflammation.

Science.gov (United States)

Pasparakis, Manolis; Haase, Ingo; Nestle, Frank O

2014-05-01

Immune responses in the skin are important for host defence against pathogenic microorganisms. However, dysregulated immune reactions can cause chronic inflammatory skin diseases. Extensive crosstalk between the different cellular and microbial components of the skin regulates local immune responses to ensure efficient host defence, to maintain and restore homeostasis, and to prevent chronic disease. In this Review, we discuss recent findings that highlight the complex regulatory networks that control skin immunity, and we provide new paradigms for the mechanisms that regulate skin immune responses in host defence and in chronic inflammation.

Creation of a Bioengineered Skin Flap Scaffold with a Perfusable Vascular Pedicle.

Science.gov (United States)

Jank, Bernhard J; Goverman, Jeremy; Guyette, Jacques P; Charest, Jon M; Randolph, Mark; Gaudette, Glenn R; Gershlak, Joshua R; Purschke, Martin; Javorsky, Emilia; Nazarian, Rosalynn M; Leonard, David A; Cetrulo, Curtis L; Austen, William G; Ott, Harald C

2017-07-01

Full-thickness skin loss is a challenging problem due to limited reconstructive options, demanding 75 million surgical procedures annually in the United States. Autologous skin grafting is the gold standard treatment, but results in donor-site morbidity and poor aesthetics. Numerous skin substitutes are available on the market to date, however, none truly functions as full-thickness skin due to lack of a vascular network. The creation of an autologous full-thickness skin analogue with a vascular pedicle would result in a paradigm shift in the management of wounds and in reconstruction of full-thickness skin defects. To create a clinically relevant foundation, we generated an acellular skin flap scaffold (SFS) with a perfusable vascular pedicle of clinically relevant size by perfusion decellularization of porcine fasciocutaneous flaps. We then analyzed the yielded SFS for mechanical properties, biocompatibility, and regenerative potential in vitro and in vivo. Furthermore, we assessed the immunological response using an in vivo model. Finally, we recellularized the vascular compartment of an SFS and reconnected it to a recipient's blood supply to test for perfusability. Perfusion decellularization removed all cellular components with preservation of native extracellular matrix composition and architecture. Biaxial testing revealed preserved mechanical properties. Immunologic response and biocompatibility assessed via implantation and compared with native xenogenic skin and commercially available dermal substitutes revealed rapid neovascularization and complete tissue integration. Composition of infiltrating immune cells showed no evidence of allorejection and resembled the inflammatory phase of wound healing. Implantation into full-thickness skin defects demonstrated good tissue integration and skin regeneration without cicatrization. We have developed a protocol for the generation of an SFS of clinically relevant size, containing a vascular pedicle, which can be

The effect of the moisture content of a local heat source on the blood flow response of the skin.

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Petrofsky, Jerrold Scott; Bains, Gurinder; Raju, Chinna; Lohman, Everett; Berk, Lee; Prowse, Michelle; Gunda, Shashi; Madani, Piyush; Batt, Jennifer

2009-09-01

Numerous studies have examined the effect of local and global heating of the body on skin blood flow. However, the effect of the moisture content of the heat source on the skin blood flow response has not been examined. Thirty-three subjects, without diabetes or cardiovascular disease, between the ages of 22 and 32 were examined to determine the relationship between the effects of dry vs. moist heat applied for the same length of time and with the skin clamped at the same skin temperature on the blood flow response of the skin. The skin, heated with an infrared heat lamp (skin temperature monitored with a thermocouple) to 40 degrees C for 15 min, was either kept moist with wet towels or, in a separate experiment, kept dry with Drierite (a desiccant) between the towels to remove any moisture. Before and after heat exposure of the forearm, blood pressure, heart rate, skin moisture content, skin temperature, and skin blood flow were recorded. The results of the experiment showed that there was no change in skin moisture after 15 min exposure to dry heat at 40 degrees C. However, with moist heat, skin moisture increased by 43.7%, a significant increase (P heat, blood flow increased from the resting value by 282.3% whereas with moist heat, blood flow increased by 386% over rest, a significant increase over dry heat (P heat was a better heating modality than dry heat. The reason may be linked to moisture sensitivity in calcium channels in the vascular endothelial cell.

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

Energy Technology Data Exchange (ETDEWEB)

Sharma, Rakesh, E-mail: rs05h@fsu.ed [Departments of Chemical Engineering and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, FL 32310 (United States)

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.

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

International Nuclear Information System (INIS)

Sharma, Rakesh

2010-01-01

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.

Dermal safety assessment of Arm & Hammer laundry products formulated for sensitive skin.

Science.gov (United States)

Frederick, Douglas M; Vorwerk, Linda; Gupta, Archana; Ghassemi, Annahita

2017-09-01

The prevalence of sensitive skin among the general population in industrialized countries is reported to be over 50%. Sensitive skin subjects often report significant reactions to contact with cosmetics, soaps and other consumer products. This paper describes the overall skin compatibility and mildness program for a newly developed, lightly fragranced, colorant free laundry product (i.e. Arm & Hammer™ Sensitive Skin plus Skin-Friendly Fresh Scent), specially formulated for individuals with sensitive skin. The skin mildness of the product was compared to Arm & Hammer™ Free & Clear liquid laundry detergent with no fragrance or colorant, and an established history of safe use by sensitive skin consumers. The test material was a liquid laundry product with a light scent formulated for sensitive skin consumers (Arm & Hammer™ Sensitive Skin plus Skin-Friendly Fresh Scent). The product was compared to commercially marketed products for sensitive skin with a history of skin safety in the marketplace, including: a very similar product formulation (Arm & Hammer™ Free & Clear with no fragrance), and several selected competitors' products. Studies were conducted among individuals with self-assessed sensitive skin (based on a questionnaire) using standard protocols for the Human Repeat Insult Patch Test (HRIPT), 10-Day Cumulative Irritation, the Wrist Band Wear test, and the Safety In-Use testing. Responses in all protocols were evaluated by visual scoring of potential dermatologic reactions, and recording any sensory effects at the time of the examination. In addition, sensory effects collected from panelists' daily diaries were also evaluated. The HRIPT confirmed that neither the fragrance alone, nor the product formulation with fragrance, induced contact sensitization in sensitive skin subjects. The 10-Day cumulative irritation study conducted using sensitive skin subjects showed highly favorable skin compatibility, and the test product was comparable to the control

The Tritiated Water Skin Barrier Integrity Test: Considerations for Acceptance Criteria with and Without 14C-Octanol.

Science.gov (United States)

Lehman, Paul A; Beatch, Kacie; Raney, Sam G; Franz, Thomas J

2017-01-01

A study was designed to assess barrier integrity simultaneously using separate compounds (probes) for polar and non-polar pathways through the skin, 3 H 2 O and 14 C-octanol, respectively; and to determine whether the two probe approach could better define barrier integrity. A 5-min dose of water containing 3 H 2 O and 14 C -octanol was applied to ex vivo human skin mounted in Franz diffusion cells. The receptor solution was sampled at 30 min, analyzed for 3 H and 14 C content, and the correlation between water and octanol absorption was determined by statistical tests suitable for non-normally distributed data. This study was conducted on skin from 37 donors with from 3 to 30 replicate skin sections per donor (a total of 426 sections). The correlation between 3 H 2 O and 14 C-octanol absorption was low (Pearson correlation coefficient = 0.3485). The 3 H 2 O absorption cutoff used in this study to select for a normal skin barrier rejected some sections in which 14 C-octanol absorption was within normal limits and accepted others in which 14 C-octanol absorption was abnormally high. The converse was true for 3 H 2 O absorption when the 14 C-octanol-based cutoff was used. The results of the 3 H 2 O test or of similar tests that primarily assess the permeability of polar pathways through the skin may not necessarily provide information relevant to the absorption of highly lipophilic compounds. Octanol, or another molecule that more closely matches the physicochemical attributes of the test compound, may characterize properties of the skin barrier that are more relevant to compounds of low water solubility.

Diagnostic evaluation of a large group of patients with immediate allergy to penicillins: the role of skin testing.

Science.gov (United States)

Torres, M J; Romano, A; Mayorga, C; Moya, M C; Guzman, A E; Reche, M; Juarez, C; Blanca, M

2001-09-01

Penicillin is no longer the most commonly prescribed beta-lactam, and the pattern of reactions has changed. We studied the diagnostic value of skin testing in penicillin-allergic subjects from a population where benzylpenicillin is not now the most frequently used beta-lactam. Patients with a history of immediate allergic reactions to penicillins were studied with: skin tests with major and minor determinants of benzylpenicillin (BPO/MDM), amoxicillin, and ampicillin; in vitro determination of specific IgE; and controlled administration for those with a positive history but negative skin and in vitro tests. A reaction was considered immediate when symptoms appeared within a maximum of 1 h after drug intake. After testing, 290 patients (71% having anaphylaxis and 29% having urticaria) proved to be allergic. Amoxicillin was involved in 64.8% and benzylpenicillin in 2.8% of the patients. Skin test positivity to at least one determinant appeared in 70% of cases, amoxicillin being the most frequent. The overall sensitivity decreased markedly when only BPO and MDM were considered. In 13.1% of patients, the diagnosis was established by in vitro test and in 16.9% by controlled administration. Of the 290 patients, 42.1% were positive to determinants generated from benzylpenicillin and 57.9% were selective responders. Sensitivity of skin tests to BPO was lower than reported, being partly replaced by minor determinants, mostly amoxicillin. The incorporation of additional reagents and the development of new tests are required, and these will probably change as the patterns of consumption vary.

Rate dependency and role of nitric oxide in the vascular response to direct cooling in human skin.

Science.gov (United States)

Yamazaki, Fumio; Sone, Ryoko; Zhao, Kun; Alvarez, Guy E; Kosiba, Wojciech A; Johnson, John M

2006-01-01

Local cooling of nonglabrous skin without functional sympathetic nerves causes an initial vasodilation followed by vasoconstriction. To further characterize these responses to local cooling, we examined the importance of the rate of local cooling and the effect of nitric oxide synthase (NOS) inhibition in intact skin and in skin with vasoconstrictor function inhibited. Release of norepinephrine was blocked locally (iontophoresis) with bretylium tosylate (BT). Skin blood flow was monitored from the forearm by laser-Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was calculated as the ratio of LDF to blood pressure. Local temperature was controlled over 6.3 cm2 around the sites of LDF measurement. Local cooling was applied at -0.33 or -4 degrees C/min. At -4 degrees C/min, CVC increased (P cooling (-4 degrees C/min) to 24 degrees C decreased (P cooling, CVC decreased at BT + saline sites relative to the precooling levels (P cooling, but not functional NOS, is an important determinant of the early non-adrenergic vasodilator response to local cooling and that functional NOS, adrenergic nerves, as well as other mechanisms play roles in vasoconstriction during prolonged local cooling of skin.

Tissue responses to fractional transient heating with sinusoidal heat flux condition on skin surface.

Science.gov (United States)

Ezzat, Magdy A; El-Bary, Alaa A; Al-Sowayan, Noorah S

2016-10-01

A fractional model of Bioheat equation for describing quantitatively the thermal responses of skin tissue under sinusoidal heat flux conditions on skin surface is given. Laplace transform technique is used to obtain the solution in a closed form. The resulting formulation is applied to one-dimensional application to investigate the temperature distribution in skin with instantaneous surface heating for different cases. According to the numerical results and its graphs, conclusion about the fractional bioheat transfer equation has been constructed. Sensitivity analysis is performed to explore the thermal effects of various control parameters on tissue temperature. The comparisons are made with the results obtained in the case of the absence of time-fractional order. © 2016 Japanese Society of Animal Science. © 2016 Japanese Society of Animal Science.

Analysis of skin conductance response during evaluation of preferences for cosmetic products

Science.gov (United States)

Ohira, Hideki; Hirao, Naoyasu

2015-01-01

We analyzed skin conductance response (SCR) as a psychophysiological index to evaluate affective aspects of consumer preferences for cosmetic products. To examine the test-retest reliability of association between preferences and SCR, we asked 33 female volunteers to complete two experimental sessions approximately 1 year apart. The participants indicated their preferences in a typical paired comparison task by choosing the better option from a combination of two products among four products. We measured anticipatory SCR prior to expressions of the preferences. We found that the mean amplitude of the SCR elicited by the preferred products was significantly larger than that elicited by the non-preferred products. The participants' preferences and corresponding SCR patterns were well preserved at the second session 1 year later. Our results supported cumulating findings that SCR is a useful index of consumer preferences that has future potential, both in laboratory and marketing settings. PMID:25709593

Reliability of candida skin test in the evaluation of T-cell function in ...

African Journals Online (AJOL)

Background: Both standardized and non-standardized candida skin tests are used in clinical practice for functional in-vivo assessment of cellular immunity with variable results and are considered not reliable under the age of 1 year. We sought to investigate the reliability of using manually prepared candida intradermal test ...

Histamine response and local cooling in the human skin: involvement of H1- and H2-receptors.

Science.gov (United States)

Grossmann, M; Jamieson, M J; Kirch, W

1999-08-01

Histamine may contribute locally to cutaneous blood flow control under normal and pathologic conditions. The objective of this study was to observe the influence of skin temperature on histamine vasodilation, and the roles of H1-and H2-receptors using novel noninvasive methods. Eleven healthy subjects received, double-blind, single doses of the H1-receptor antagonist cetirizine (10 mg), cetirizine (10 mg) plus the H2-receptor antagonist cimetidine (400 mg), or placebo on separate occasions. Histamine was dosed cumulatively by iontophoresis to the forearm skin at 34 degrees C and 14 degrees C. Laser-Doppler flux (LDF) was measured at the same sites using customised probeholder/iontophoretic chambers with Peltier cooling elements. Finger mean arterial pressure (MAP) was measured and cutaneous vascular conductance calculated as LDF/MAP. Histamine vasodilation was reduced in cold skin. Cetirizine shifted the histamine dose-response at both temperatures: statistically significantly at 14 degrees C only. Combined H1- and H2-receptor antagonism shifted the response significantly at both temperatures. H1- and H2-receptors mediate histamine-induced skin vasodilation. The sensitivity of these receptors, particularly the H1- receptor, is attenuated at low skin temperature. Whether the reduced effect in cold skin represents specific receptor or postreceptor desensitization, or nonspecific attenuation of cutaneous vasodilation remains to be elucidated.

Concordant or discordant results by the tuberculin skin test and the quantiFERON-TB test in children reflect immune biomarker profiles

DEFF Research Database (Denmark)

Dhanasekaran, S; Jenum, S; Stavrum, R

2014-01-01

The tuberculin skin test (TST) and QuantiFERON-TB-Gold-In-tube (QFTGIT) are adjunctive tests used in the diagnosis of pediatric tuberculosis (TB). Neither test can rule out TB; however, a positive test usually triggers preventive treatment in TB contacts aged <5 years. TST and QFTGIT can give div...

Development, validation and testing of a skin sampling method for assessment of metal exposure.

Science.gov (United States)

Erfani, Behnaz; Midander, Klara; Lidén, Carola; Julander, Anneli

2017-07-01

Nickel, cobalt and chromium are frequent skin sensitizers. Skin exposure results in eczema in sensitized individuals, the risk being related to the skin dose. To develop a self-sampling method for quantification of skin exposure to metals, to validate the method, and to assess its feasibility. Defined metal doses (0.01-5 µg) were applied to the fingers of 5 participants. Skin areas (2 cm 2 ) were sampled with 1% HNO 3 , either as 0.1 ml on a swab, or as 0.5 ml on a wipe. Furthermore, 17 participants performed self-sampling by swab after 2 h of leisure activity. Samples were extracted in 1% HNO 3 and analysed by inductively coupled plasma mass spectrometry. The sampling efficiency by swab was 46%, as compared with 93% for acid wipe sampling, for all tested doses. Most metal from the skin dose was detected in the first swab (33-43%). Despite lower sampling efficiency by swab, skin doses of metals following 2 h of leisure activity without hand washing were quantified in all participants, and ranged from 0.0016 to 0.15 µg/cm 2 , from 0.00014 to -0.0020 µg/cm 2 and from 0.00048 to -0.027 µg/cm 2 for nickel, cobalt, and chromium, respectively. The results indicate a future potential of skin sampling by swab to detect and monitor metals on skin by self-sampling. This will contribute to better knowledge of metal skin exposure among dermatitis patients, workers, and the general population. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Impact of Age and Insulin-Like Growth Factor-1 on DNA Damage Responses in UV-Irradiated Human Skin.

Science.gov (United States)

Kemp, Michael G; Spandau, Dan F; Travers, Jeffrey B

2017-02-26

The growing incidence of non-melanoma skin cancer (NMSC) necessitates a thorough understanding of its primary risk factors, which include exposure to ultraviolet (UV) wavelengths of sunlight and age. Whereas UV radiation (UVR) has long been known to generate photoproducts in genomic DNA that promote genetic mutations that drive skin carcinogenesis, the mechanism by which age contributes to disease pathogenesis is less understood and has not been sufficiently studied. In this review, we highlight studies that have considered age as a variable in examining DNA damage responses in UV-irradiated skin and then discuss emerging evidence that the reduced production of insulin-like growth factor-1 (IGF-1) by senescent fibroblasts in the dermis of geriatric skin creates an environment that negatively impacts how epidermal keratinocytes respond to UVR-induced DNA damage. In particular, recent data suggest that two principle components of the cellular response to DNA damage, including nucleotide excision repair and DNA damage checkpoint signaling, are both partially defective in keratinocytes with inactive IGF-1 receptors. Overcoming these tumor-promoting conditions in aged skin may therefore provide a way to lower aging-associated skin cancer risk, and thus we will consider how dermal wounding and related clinical interventions may work to rejuvenate the skin, re-activate IGF-1 signaling, and prevent the initiation of NMSC.

Impact of Age and Insulin-Like Growth Factor-1 on DNA Damage Responses in UV-Irradiated Human Skin

Directory of Open Access Journals (Sweden)

Michael G. Kemp

2017-02-01

Full Text Available The growing incidence of non-melanoma skin cancer (NMSC necessitates a thorough understanding of its primary risk factors, which include exposure to ultraviolet (UV wavelengths of sunlight and age. Whereas UV radiation (UVR has long been known to generate photoproducts in genomic DNA that promote genetic mutations that drive skin carcinogenesis, the mechanism by which age contributes to disease pathogenesis is less understood and has not been sufficiently studied. In this review, we highlight studies that have considered age as a variable in examining DNA damage responses in UV-irradiated skin and then discuss emerging evidence that the reduced production of insulin-like growth factor-1 (IGF-1 by senescent fibroblasts in the dermis of geriatric skin creates an environment that negatively impacts how epidermal keratinocytes respond to UVR-induced DNA damage. In particular, recent data suggest that two principle components of the cellular response to DNA damage, including nucleotide excision repair and DNA damage checkpoint signaling, are both partially defective in keratinocytes with inactive IGF-1 receptors. Overcoming these tumor-promoting conditions in aged skin may therefore provide a way to lower aging-associated skin cancer risk, and thus we will consider how dermal wounding and related clinical interventions may work to rejuvenate the skin, re-activate IGF-1 signaling, and prevent the initiation of NMSC.

Fibroblast radiosensitivity versus acute and late normal skin responses in patients treated for breast cancer

International Nuclear Information System (INIS)

Brock, W.A.; Wike, J.; Tucker, S.L.

1995-01-01

To determine if the radiosensitivity of normal human skin fibroblasts, measured in early passage cultures, is significantly correlated with the degree of acute or late normal skin damage in patients treated for breast cancer with radiotherapy. To test assay reproducibility, SF2 values derived from paired biopsies of the same patient (12 cases) were compared. A reasonably good correlation (p = 0.075) was obtained for SF2s determined by high dose-rate irradiations with immediated plating, but not for delayed plating or low dose-rate treatments. The median coefficient of variation in the replicate SF2s after high dose-rate treatment and immediate plating was 13%, suggesting that the poor correlation in paired SF2 values is due to the magnitude of the uncertainty in SF2 relative to the overall spread in SF2 values between patients (CV = 28%). Individual SF2 values and averaged values from patients with data from two biopsies were compared with the acute and late clinical reactions. A significant negative correlation was found between SF2 and relative clinical response, but only when averaged high dose-rate SF2 values and telangiectasia scores were compared. There was no significant correlation between average SF2 values and acute responses or between individual SF2 measurements and either the acute or late clinical response. The results of this study suggest that the degree of late telangiectasia is at least partially dependent upon the intrinsic cellular radiosensitivity of normal fibroblasts, but the relationship is not clear cut. Multiple replicate assays are necessary to obtain reliable estimates of fibroblast SF2 values using current techniques. 20 refs., 3 figs., 3 tabs

HLA-DPDQDR is expressed in all lesional skin from patients with autoimmune skin diseases

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Ana Maria Abreu Velez

2014-04-01

Full Text Available Introduction: Human genes responsible for human antigen presentation and transplant rejection functions are located on the short arm of Chromosome 6 and are called the Major Histocompatibility Complex (MHC. Moreover, the primary physiologic function of MHC molecules is to present peptides to T lymphocytes. MHC molecules are integral components of the ligands that most T cells recognize, since the T cell receptor (TCR has specificity for complexes of foreign antigenic peptides, as well as self-MHC molecules. Aim: Our investigation attempts to investigate the presence of HLA-DPDQDR within lesional skin biopsies from patients affected by autoimmune skin blistering diseases (ABDs. Materials and Methods: We utilized immunohistochemistry (IHC to evaluate the presence of HLA-DPDQDR in lesional skin biopsies of patients affected by ABDs. We tested 30 patients with endemic pemphigus foliaceus (EPF, 15 controls from the EPF endemic area, and 15 biopsies from healthy controls from the USA. We also tested archival biopsies from patients with selected ABDs, including 30 patients with bullous pemphigoid (BP, 20 with pemphigus vulgaris (PV, 8 with pemphigus foliaceus (PF, 14 with dermatitis herpetiformis (DH and 2 with epidermolysis bullosa acquisita (EBA. Results: Most ABD biopsies stained positive for HLA-DPDQDR in the lesional blisters and/or inflamed neurovascular plexus in the superficial dermis, and also at mesenchymal-endothelial like-cell junctions in the dermis. In BP, EBA and EPF, the HLA-DPDQDR staining was also seen in the dermal eccrine sweat gland coils and and ducts. Conclusion: Here, we document that HLA-DPDQDR is expressed in several anatomic areas of lesional skin in patients with ABDs. Notably, HLA-DPDQDR positivity was also consistently present in areas of the classic immune response in pemphigus epidermal keratinocytic intercellular junctions, and at basement membrane sites in bullous pemphigoid and other subepidermal blistering diseases.

Comparison of blood volume pulse and skin conductance responses to mental and affective stimuli at different anatomical sites

International Nuclear Information System (INIS)

Kushki, Azadeh; Fairley, Jillian; Merja, Satyam; King, Gillian; Chau, Tom

2011-01-01

Measurements of blood volume pulse (BVP) and skin conductance are commonly used as indications of psychological arousal in affective computing and human–machine interfaces. To date, palmar surfaces remain the primary site for these measurements. Placement of sensors on palmar surfaces, however, is undesirable when recordings are fraught with motion and pressure artifacts. These artifacts are frequent when the human participant has involuntary movements as in hyperkinetic cerebral palsy. This motivates the use of alternative measurement sites. The present study examined the correlation between measurements of blood volume pulse and skin conductance obtained from three different sites on the body (fingers, toes and ear for BVP; fingers, toes and arch of the foot for skin conductance) in response to cognitive and affective stimuli. The results of this pilot study indicated significant inter-site correlation among signal features derived from different sites, with the exception of BVP amplitude, the number of electrodermal reactions and the slope of the electrodermal activity response. We attribute these differences in part to inter-site discrepancies in local skin conditions, such as skin temperature. Despite these differences, significant changes from baseline were present in the responses to the cognitive and affective stimuli at non-palmar sites, suggesting that these sites may provide viable signal measurements for use in affective computing and human–machine interface applications

Thermosensitive Hydrogel Mask Significantly Improves Skin Moisture and Skin Tone; Bilateral Clinical Trial

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Anna Quattrone

2017-06-01

Full Text Available Objective: A temperature-sensitive state-changing hydrogel mask was used in this study. Once it comes into contact with the skin and reaches the body temperature, it uniformly and quickly releases the active compounds, which possess moisturizing, anti-oxidant, anti-inflammatory and regenerative properties. Methods: An open label clinical trial was conducted to evaluate the effects of the test product on skin hydration, skin tone and skin ageing. Subjects applied the product to one side of their face and underwent Corneometer® and Chromameter measurements, Visual assessment of facial skin ageing and facial photography. All assessments and Self-Perception Questionnaires (SPQ were performed at baseline, after the first application of the test product and after four applications. Results: After a single treatment we observed an increase in skin moisturisation, an improvement of skin tone/luminosity and a reduction in signs of ageing, all statistically significant. After four applications a further improvement in all measured parameters was recorded. These results were confirmed by the subjects’ own perceptions, as reported in the SPQ both after one and four applications. Conclusion: The hydrogel mask tested in this study is very effective in improving skin hydration, skin radiance and luminosity, in encouraging an even skin tone and in reducing skin pigmentation.

Assessment of pepper spray product potency in Asian and Caucasian forearm skin using transepidermal water loss, skin temperature and reflectance colorimetry.

Science.gov (United States)

Pershing, Lynn K; Reilly, Christopher A; Corlett, Judy L; Crouch, Dennis J

2006-01-01

Historically, pepper spray product potency has been established using a taste test evaluation. A taste test is subjective and may not be appropriate for assessing pepper potency in skin. The current study evaluated chemically diverse pepper sprays in human forearm skin using three objective, noninvasive parameters: transepidermal water loss, skin surface temperature and erythema, as a means for assessing dermal pharmacology, toxicology and product potency. Five commercial pepper spray products containing various capsaicinoid analogs at various concentrations were evaluated in duplicate on volar forearms of six Caucasians and six Asians using a 10 min exposure. Mean surface skin temperature, transepidermal water loss results were highly variable and therefore did not demonstrate dose responsive behavior to increasing capsaicinoid concentrations. Erythema, as measured by increases in a* (reflected light in the red-to-green color spectrum) of the L*a*b* uniform color scale, was superior among parameters evaluated in discriminating pepper spray potency and correlated well with the relative and total capsaicinoid concentration in the products. Products containing greater than 16 mg ml(-1) capsaicinoid concentration produced greater erythema responses in Caucasians than Asians. Asians responded greater to the synthetic analog, nonivamide, than to mixtures of capsaicinoids, while Caucasians responded equally to both capsaicinoid analogs. Thus, pepper spray product potency in human skin reflects the total capsaicinoid concentration, the specific capsaicin analog(s) present, and the race of the individual exposed. The finding that the reflectance colorimeter a* scale can differentiate these parameters in skin will have a significant impact on evaluating the use and efficacy of pepper spray products in humans. 2005 John Wiley & Sons, Ltd.

Effects of locus coeruleus stimulation on the responses of SI neurons of the rat to controlled natural and electrical stimulation of the skin.

Science.gov (United States)

Snow, P J; Andre, P; Pompeiano, O

1999-02-01

very large size probably corresponding to large layer V pyramidal cells, were often difficult to activate with air puffs applied at the centre of the receptive field (RF) and were submitted to electrical stimulation of the skin. 4. Among the 59 isolated SI units tested either to air puffs (45 neurons) or to electrical skin stimulation (14 neurons), 15 units (i.e., 25.4%) were facilitated, while 12 units (i.e., 20.3%) were inhibited following stimulation of the LC complex. 5. A marked feature of the facilitatory effects which usually involved the predominant response to the first air puff, but also the smaller response to the second puff, was that the increase in the number of spikes per stimulus was accompanied by a temporal focusing of the responses characterized by a clear tightening of the latency and narrowing of the peak of activity, which was often accompanied by some level of tonic inhibition of the background discharge. Thus, LC stimulation increased the signal-to-noise ratio of SI neuronal responses to skin stimulation. When inhibitory effects were induced by LC stimulation, they clearly affected the unit response to the first air puff, which was severely depressed. However, the response to the second puff could be facilitated, suggesting that LC stimulation might have produced inhibition of those inhibitory interneurons responsible for the postexcitatory inhibition of the units under examination. Evidence for spatial focusing of the response was not easily documented. In some units, however, LC stimulation produced either facilitation of the responses to puffs at the receptive field center and inhibition of the responses to puffs at the edge at the receptive field or vice versa. 6. Since the LC complex contains in the rat a predominant population of noradrenergic neurons, it is likely that the effects described above were mainly due to activation of these noradrenergic neurons. 7. (ABSTRACT TRUNCATED)

Estrogens and aging skin

OpenAIRE

Thornton, M. Julie

2013-01-01

Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity...

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

Science.gov (United States)

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. 2016 FRAME.

Deep tissue injury in development of pressure ulcers: a decrease of inflammasome activation and changes in human skin morphology in response to aging and mechanical load.

Directory of Open Access Journals (Sweden)

Olivera Stojadinovic

Full Text Available Molecular mechanisms leading to pressure ulcer development are scarce in spite of high mortality of patients. Development of pressure ulcers that is initially observed as deep tissue injury is multifactorial. We postulate that biomechanical forces and inflammasome activation, together with ischemia and aging, may play a role in pressure ulcer development. To test this we used a newly-developed bio-mechanical model in which ischemic young and aged human skin was subjected to a constant physiological compressive stress (load of 300 kPa (determined by pressure plate analyses of a person in a reclining position for 0.5-4 hours. Collagen orientation was assessed using polarized light, whereas inflammasome proteins were quantified by immunoblotting. Loaded skin showed marked changes in morphology and NLRP3 inflammasome protein expression. Sub-epidermal separations and altered orientation of collagen fibers were observed in aged skin at earlier time points. Aged skin showed significant decreases in the levels of NLRP3 inflammasome proteins. Loading did not alter NLRP3 inflammasome proteins expression in aged skin, whereas it significantly increased their levels in young skin. We conclude that aging contributes to rapid morphological changes and decrease in inflammasome proteins in response to tissue damage, suggesting that a decline in the innate inflammatory response in elderly skin could contribute to pressure ulcer pathogenesis. Observed morphological changes suggest that tissue damage upon loading may not be entirely preventable. Furthermore, newly developed model described here may be very useful in understanding the mechanisms of deep tissue injury that may lead towards development of pressure ulcers.

The choice of sensitive skin layer responsible for aftereffects of daily irradiation of the skin

International Nuclear Information System (INIS)

Keirim-Markus, I.B.

1992-01-01

The choice of sensitive human skin layer manifesting in delayed period after daily irradiation of the human skin (stochastic and determined effects) was evaluated. It was established that delayed aftereffects of daily radiation of the skin manifested as epidem damages. This layer of papilla derma of 10-15 mg/cm 2 thick situated at the great part of body surface, 15 mg/cm 2 on dorsal side of hands and 40 mg/cm 2 on palms and pillows of the fingers. Sensitive layer of skin dosimeter for a control of daily irradiation of people must have the same geometry

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

Science.gov (United States)

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.

Optimization of gelatine extraction from grass carp (Catenopharyngodon idella) fish skin by response surface methodology.

Science.gov (United States)

Kasankala, Ladislaus M; Xue, Yan; Weilong, Yao; Hong, Sun D; He, Qian

2007-12-01

To establish the optimum gelatine extraction conditions from grass carp fish skin, response surface methodology (RSM) was adopted in this study. The effects of concentration of HCl (%, A), pre-treatment time (h, B), extraction temperature ( degrees C, C) and extraction time (h, D) were studied. The responses were yield (%) and gel strength (g). A=1.19%, B=24 h, C=52.61 degrees C and D=5.12h were determined as the optimum conditions while the predicted responses were 19.83% yield and 267 g gel strength. Gelling and melting points were 19.5 degrees C and 26.8 degrees C, respectively. Moreover, grass carp gelatine showed high contents of imino acids (proline and hydroxyproline) 19.47%. RSM provided a powerful tool to optimize the extraction parameters and the results may be adapted for industrial extraction of gelatine from grass carp fish skins.

Skin response to cobalt 60 irradiation and the consequences for matching the color of facial prostheses

International Nuclear Information System (INIS)

van Oort, R.P.; Vermey, J.; Ten Bosch, J.J.

1984-01-01

A radiotherapy treatment ( 60 Co) of cancer in the head and neck region causes side effects in the skin that postpone the facial prosthetic treatment. The increasing and fading erythema and pigmentation of the skin was investigated with the use of a subtractive colorimeter. This method was verified with photographs scored according to the Oxford scoring system. Fourteen patients were investigated during a period of 24 weeks. The mean colorimetric skin response showed a peak 6 weeks after the onset of irradiation. Six to 7 weeks later, there was no significant difference between the skin color before and after irradiation. At this time the dry desquamation of the skin is healed. From this viewpoint, the color matching procedure for a facial prosthesis may start not earlier than 15 weeks from the onset of irradiation. If a nonirradiated control field in the facial region is present, a color match for the facial prosthesis can be started just after the irradiation period

Chemical signals of fish skin for the attachment response of Acanthostomum brauni cercariae.

Science.gov (United States)

Haas, W; de Nuñez, M O

1988-01-01

The chemical signals of the skin surface of fish, which stimulate the attachment responses of Acanthostomum brauni cercariae, were identified by offering chemicals and fish-skin extracts in agarose substrates to the cercariae. Smaller molecules such as amino acids, fatty acids, monosaccharides, electrolytes, urea, and carbonate solutions did not stimulate attachments, but hyaluronic acid had some effects. Bovine submaxillary glycoproteins had a strong stimulating activity that disappeared after neuraminidase digestion. The stimulating components of the skin surface of fish were hydrophilic substances with molecular weights of more than 10,000. They were sensitive to neuraminidase digestion but not to hyaluronidase digestion and thus can be identified as glycoproteins. A. brauni cercariae respond only to the complete glycoprotein molecules and not to their monosaccharide components. The known attachment triggers of other cercariae are small molecules. Large glycoproteins as host signals for A. brauni cercariae may be an adaptation to muddy habitats, where various substances with low molecular weights may interfere with the host identification.

Mechanical properties of striped bass fish skin: Evidence of an exotendon function of the stratum compactum.

Science.gov (United States)

Szewciw, Lawrence; Barthelat, Francois

2017-09-01

Teleost fish skin is a multifunctional natural material with high penetration resistance owing to specialized puncture mechanisms of both the individual scale and the intact scaled integument. In this paper, we explore the possible additional role of the skin in fish undulatory locomotion by examining the structural and mechanical properties of the dermal stratum (s.) compactum layer of striped bass (Morone saxatilis) skin. The structure, mechanical response and function of s. compactum was investigated by combining several methods: optical microscopy and histology, tensile tests on descaled skin specimens in different anatomical locations and orientations, puncture tests, and flexural tests on whole fish with disruption of the s. compactum. Local histological features of the s. compactum, such as collagen fiber angle and degree of crimping, were shown to explain corresponding patterns determined for the tensile properties of the skin along the long axis of the fish, including changes in stiffness, strength and locking strain at stiffening. The fish bending tests demonstrated a tendon-like response of the whole fish and a significant contribution of the s. compactum to the flexural stiffness of the fish. Collectively, the findings show that the s. compactum is a strong tissue with a tendon-like nonlinear response, and which provides an appreciable mechanical protection against sharp puncture and lacerations. Our results also support the theory of an exotendon function of the s. compactum in teleost fish skin. These findings may inspire the design of new multifunctional protective and locomotory systems for a variety of engineering applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Food allergies in children: a comparison of parental reports and skin prick test results

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Camilia Metadea Aji Savitri

2018-04-01

Full Text Available Background Food allergy is common in children and its prevalence is generally on the rise. Imprecise parental reports about reactions to particular foods can lead to unnecessary restrictions. Since children have specific growth requirements, such nutritional restrictions may have disturbing effects on children’s growth and development. Objective To compare parental reports on food reactions to skin prick test results in their children. Method Retrospective, cross sectional study using patient’s medical record data during one-year study period. Data were analyzed manually and statistically, to assess the degree of agreement (Kappa’s coefficient and significance (P. Results We collected data from 154 subjects aged 0-18 years. For every allergen assessed, parents reported more food reactions than positive skin prick test results. Allergy incidence were caused, in order, by cow’s milk and chicken (25.3%, eggs (22.1%, chocolate (20.1%, fruits (14.3%, seafood (13%, and saltwater fish (1.9%. Kappa coefficient are all poor (0.05 except for chicken (P=0.02. Conclusion Most parents tend to overestimate which food cause reactions in their children, as reactions reported were not necessarily allergenic. Therefore, every patient experiencing allergy reactions should undergo skin prick testing to confirm the possibility of allergy.

Raman spectroscopy: in vivo quick response code of skin physiological status

Science.gov (United States)

Vyumvuhore, Raoul; Tfayli, Ali; Piot, Olivier; Le Guillou, Maud; Guichard, Nathalie; Manfait, Michel; Baillet-Guffroy, Arlette

2014-11-01

Dermatologists need to combine different clinically relevant characteristics for a better understanding of skin health. These characteristics are usually measured by different techniques, and some of them are highly time consuming. Therefore, a predicting model based on Raman spectroscopy and partial least square (PLS) regression was developed as a rapid multiparametric method. The Raman spectra collected from the five uppermost micrometers of 11 healthy volunteers were fitted to different skin characteristics measured by independent appropriate methods (transepidermal water loss, hydration, pH, relative amount of ceramides, fatty acids, and cholesterol). For each parameter, the obtained PLS model presented correlation coefficients higher than R2=0.9. This model enables us to obtain all the aforementioned parameters directly from the unique Raman signature. In addition to that, in-depth Raman analyses down to 20 μm showed different balances between partially bound water and unbound water with depth. In parallel, the increase of depth was followed by an unfolding process of the proteins. The combinations of all these information led to a multiparametric investigation, which better characterizes the skin status. Raman signal can thus be used as a quick response code (QR code). This could help dermatologic diagnosis of physiological variations and presents a possible extension to pathological characterization.

The phenomenon of skin lightening: Is it right to be light?

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Lester M. Davids

2016-11-01

Full Text Available Chemicals capable of lightening the skin variously known as skin-bleaching, skin-lightening, depigmenting, skin-evening and skin-brightening agents are among the most commonly used skin preparations in the world. Globally, Africa reportedly exhibits a high prevalence of skin lightener use. In this review, we provide both clinical and social perspectives on skin lightener use in Africa, with particular emphasis on South Africa. We narratively explore the timeline associated with skin lightener use in South Africa and attempt to interweave the social rhetoric of this specific paradigm. Despite the risks associated with exposing the skin to known constituents of these formulations, such as hydroquinone and mercury, chronic use continues. In spite of legislation banning hydroquinone and mercury in cosmetics in South Africa, these ingredients are present in widely available products. We recommend better implementation of policies and greater ethical responsibility of multinational cosmetic companies in addition to the initiation of a system of random product testing and penalties that could improve industry compliance.

Standardisation of defined approaches for skin sensitisation testing to support regulatory use and international adoption: position of the International Cooperation on Alternative Test Methods.

Science.gov (United States)

Casati, S; Aschberger, K; Barroso, J; Casey, W; Delgado, I; Kim, T S; Kleinstreuer, N; Kojima, H; Lee, J K; Lowit, A; Park, H K; Régimbald-Krnel, M J; Strickland, J; Whelan, M; Yang, Y; Zuang, Valérie

2018-02-01

Skin sensitisation is the regulatory endpoint that has been at the centre of concerted efforts to replace animal testing in recent years, as demonstrated by the Organisation for Economic Co-operation and Development (OECD) adoption of five non-animal methods addressing mechanisms under the first three key events of the skin sensitisation adverse outcome pathway. Nevertheless, the currently adopted methods, when used in isolation, are not sufficient to fulfil regulatory requirements on the skin sensitisation potential and potency of chemicals comparable to that provided by the regulatory animal tests. For this reason, a number of defined approaches integrating data from these methods with other relevant information have been proposed and documented by the OECD. With the aim to further enhance regulatory consideration and adoption of defined approaches, the European Union Reference Laboratory for Alternatives to Animal testing in collaboration with the International Cooperation on Alternative Test Methods hosted, on 4-5 October 2016, a workshop on the international regulatory applicability and acceptance of alternative non-animal approaches, i.e., defined approaches, to skin sensitisation assessment of chemicals used in a variety of sectors. The workshop convened representatives from more than 20 regulatory authorities from the European Union, United States, Canada, Japan, South Korea, Brazil and China. There was a general consensus among the workshop participants that to maximise global regulatory acceptance of data generated with defined approaches, international harmonisation and standardisation are needed. Potential assessment criteria were defined for a systematic evaluation of existing defined approaches that would facilitate their translation into international standards, e.g., into a performance-based Test Guideline. Informed by the discussions at the workshop, the ICATM members propose practical ways to further promote the regulatory use and facilitate

Tuberculin skin testing: Spectrum of adverse reactions.

Science.gov (United States)

Praveen, Ramar; Bahuguna, Amit; Dhadwal, Bhumesh Singh

2015-01-01

Tuberculin skin testing (TST) is one of the primary diagnostic modalities recommended by the World Health Organization (WHO) and the National Institute for Health and Care Excellence (NICE) study conducted in the United Kingdom (UK) for diagnosing tuberculosis (TB). Even after acceptance as a diagnostic modality and stern standardization, TST has its own flaws that include a spectrum of adverse reactions. We report a series of cases with a spectrum of adverse reactions occurring with a higher frequency than present in the available evidence. The study has some demerits such as being a retrospective one with interobserver variation and lack of histopathological confirmation. The observation is presented to accentuate the fact that adverse reactions are not a rarity and that further studies are required to establish the cause and exact incidence of the same.

Probabilistic hazard assessment for skin sensitization potency by dose–response modeling using feature elimination instead of quantitative structure–activity relationships

Science.gov (United States)

McKim, James M.; Hartung, Thomas; Kleensang, Andre; Sá-Rocha, Vanessa

2016-01-01

Supervised learning methods promise to improve integrated testing strategies (ITS), but must be adjusted to handle high dimensionality and dose–response data. ITS approaches are currently fueled by the increasing mechanistic understanding of adverse outcome pathways (AOP) and the development of tests reflecting these mechanisms. Simple approaches to combine skin sensitization data sets, such as weight of evidence, fail due to problems in information redundancy and high dimension-ality. The problem is further amplified when potency information (dose/response) of hazards would be estimated. Skin sensitization currently serves as the foster child for AOP and ITS development, as legislative pressures combined with a very good mechanistic understanding of contact dermatitis have led to test development and relatively large high-quality data sets. We curated such a data set and combined a recursive variable selection algorithm to evaluate the information available through in silico, in chemico and in vitro assays. Chemical similarity alone could not cluster chemicals’ potency, and in vitro models consistently ranked high in recursive feature elimination. This allows reducing the number of tests included in an ITS. Next, we analyzed with a hidden Markov model that takes advantage of an intrinsic inter-relationship among the local lymph node assay classes, i.e. the monotonous connection between local lymph node assay and dose. The dose-informed random forest/hidden Markov model was superior to the dose-naive random forest model on all data sets. Although balanced accuracy improvement may seem small, this obscures the actual improvement in misclassifications as the dose-informed hidden Markov model strongly reduced "false-negatives" (i.e. extreme sensitizers as non-sensitizer) on all data sets. PMID:26046447

Decontamination efficiency of detergents on the market for the skin contaminated with radioactive materials. The comparative test (1)

International Nuclear Information System (INIS)

Miyabe, Kenjiro; Ninomiya, Kazushi; Takasaki, Koji; Horiuchi, Nobuharu; Yasunaka, Hideo; Izumi, Yuichi

1999-04-01

Contamination incidence on human body and skin happens sometimes during radiation works in controlled area. The radioactive surface contamination should be removed from the skin as soon as possible for radiation control and exposure management. Titanium oxide paste, which is reserved as a detergent for decontamination, has a satisfactory and reliable result for decontamination effects. The titanium oxide paste, however, has a short preservation period, and must be updated and supplied every serenal months. Decontamination tests for about 60 kinds of detergents on the market were carried out with swine and radioactive material, Ce-144. Radioactive solution of Ce-144 was dropped on the test samples of swine skin, which were left for 5 min or 40 min as it is. Radioactivities of the samples were measured before and after washing by the detergents. As a result of the decontamination tests, 22 kinds of detergents on the market which have a similar decontamination efficiency to the titanium oxide paste were selected. It was also ascertained that the decontamination efficiency of all the detergents decreased on the test samples which were immersed in the radioactive solution for 40 min and wounded on skin surface. (Suetake, M.)

Skin rash in patients treated with neoadjuvant erlotinib (Tarceva in resectable non-small cell lung cancer: Predictor for tumor response and survival?

Directory of Open Access Journals (Sweden)

Van Gool MH

2017-08-01

Full Text Available Background: Skin rash during treatment with epidermal growth factor receptor (EGFR-tyrosine kinase inhibitors (TKI has been reported to be predictive for response and survival in patients with advanced non-small cell lung cancer (NSCLC. The aim of this analysis was to evaluate whether skin rash during treatment (as a biomarker in a preoperative setting was related to response and survival. Methods: This study was designed as an open-label phase II trial (also known as M06NEL. Patients received preoperative erlotinib (Tarceva 150 mg once daily for 3 weeks. Skin toxicity during treatment was analysed in relation to metabolic and histopathological response, overall survival (OS and progression-free survival (PFS. Results: In total 59 patients (25 male, 34 female were eligible for analysis. In 39 patients (66% skin toxicity occurred. According to National Cancer Institute Common Toxicity Criteria (NCICTC, Grade 1 toxicity was seen in 15 patients (25%, Grade 2 in 19 patients (32% and Grade 3 in five patients (8%. None of the patients showed skin toxicity Grade 4 and 5. The median follow up was 74 months. Thirty-six patients (61% were alive at time of analysis. Twenty-seven patients (46% showed disease progression during follow up. Hazard ratios (HR indicated lower risk of death (HR = 0.66, 95%CI: 0.29 - 1.50 and progression (HR = 0.64, 0.30 - 1.36, although in this small group results were not significant. Skin rash did not adequately predict response. Conclusions: In this neoadjuvant setting with limited treatment time in patients with early stage NSCLC, skin rash was not associated with response and survival and cannot be used as an early biomarker.

Prefrontal oxygenation correlates to the responses in facial skin blood flows during exposure to pleasantly charged movie

OpenAIRE

Matsukawa, Kanji; Endo, Kana; Asahara, Ryota; Yoshikawa, Miho; Kusunoki, Shinya; Ishida, Tomoko

2017-01-01

Abstract Our laboratory reported that facial skin blood flow may serve as a sensitive tool to assess an emotional status. Cerebral neural correlates during emotional interventions should be sought in relation to the changes in facial skin blood flow. To test the hypothesis that prefrontal activity has positive relation to the changes in facial skin blood flow during emotionally charged stimulation, we examined the dynamic changes in prefrontal oxygenation (with near‐infrared spectroscopy) and...

Analysis of the suitableness of some enzymatic tests for estimation the degree of radiational injury of skin

International Nuclear Information System (INIS)

Matyushichev, V.B.; Kornikov, V.V.; Taratukhin, V.R.; Timofeeva, O.E.; Vereshchagina, E.M.

1981-01-01

Possibilities to characterize the degree of skin injury of white male-rats on the 14th day after external 85 Kr #betta#-irradiation at 3, 4, 5, 6, 7, 8, 9, 10 krad doses by activity levels of alkali and acid DNA-ases of skin and blood plasma as well as skin and plasma alpha-amylase have been studied using the methods of factor analysis. It has been ascertained that alkali and acid DNA-ases of skin have the best indicating properties. Other tests in the main only supplement the general picture. The combined accounting of properties of alkali and acid DNA-ases of skin as well as acid DNA-ase and alpha-amylase of blood plasma permits to demarkate individuals completely according to the degree (zero - 3d) of skin injuries. These indicators can be used in practical dosimetry

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

NARCIS (Netherlands)

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.

2012-01-01

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

Identification of low allergenic apple cultivars using skin prick tests and oral food challenges

NARCIS (Netherlands)

Vlieg-Boerstra, B. J.; van de Weg, W. E.; van der Heide, S.; Kerkhof, M.; Arens, P.; Heijerman-Peppelman, G.; Dubois, A. E. J.

2011-01-01

As oral allergy syndrome (OAS) symptoms to apple are frequent, we aimed to identify low allergenic apple cultivars and to validate the prick-to-prick skin prick test (SPT) as a suitable screening method. Sixty-eight apple cultivars were tested by SPTs in 33 Dutch adults with OAS, before and during

Identification of low allergenic apple cultivars using skin prick tests and oral food challenges

NARCIS (Netherlands)

Vlieg-Boerstra, B. J.; van de Weg, W. E.; van der Heide, S.; Kerkhof, M.; Arens, P.; Heijerman-Peppelman, G.; Dubois, A. E. J.

P>Background: As oral allergy syndrome (OAS) symptoms to apple are frequent, we aimed to identify low allergenic apple cultivars and to validate the prick-to-prick skin prick test (SPT) as a suitable screening method. Methods: Sixty-eight apple cultivars were tested by SPTs in 33 Dutch adults with

LLNA variability: An essential ingredient for a comprehensive assessment of non-animal skin sensitization test methods and strategies.

Science.gov (United States)

Hoffmann, Sebastian

2015-01-01

The development of non-animal skin sensitization test methods and strategies is quickly progressing. Either individually or in combination, the predictive capacity is usually described in comparison to local lymph node assay (LLNA) results. In this process the important lesson from other endpoints, such as skin or eye irritation, to account for variability reference test results - here the LLNA - has not yet been fully acknowledged. In order to provide assessors as well as method and strategy developers with appropriate estimates, we investigated the variability of EC3 values from repeated substance testing using the publicly available NICEATM (NTP Interagency Center for the Evaluation of Alternative Toxicological Methods) LLNA database. Repeat experiments for more than 60 substances were analyzed - once taking the vehicle into account and once combining data over all vehicles. In general, variability was higher when different vehicles were used. In terms of skin sensitization potential, i.e., discriminating sensitizer from non-sensitizers, the false positive rate ranged from 14-20%, while the false negative rate was 4-5%. In terms of skin sensitization potency, the rate to assign a substance to the next higher or next lower potency class was approx.10-15%. In addition, general estimates for EC3 variability are provided that can be used for modelling purposes. With our analysis we stress the importance of considering the LLNA variability in the assessment of skin sensitization test methods and strategies and provide estimates thereof.

Predicting the outcome of oral food challenges with hen's egg through skin test end-point titration.

Science.gov (United States)

Tripodi, S; Businco, A Di Rienzo; Alessandri, C; Panetta, V; Restani, P; Matricardi, P M

2009-08-01

Oral food challenge (OFC) is the diagnostic 'gold standard' of food allergies but it is laborious and time consuming. Attempts to predict a positive OFC through specific IgE assays or conventional skin tests so far gave suboptimal results. To test whether skin test with titration curves predict with enough confidence the outcome of an oral food challenge. Children (n=47; mean age 6.2 +/- 4.2 years) with suspected and diagnosed allergic reactions to hen's egg (HE) were examined through clinical history, physical examination, oral food challenge, conventional and end-point titrated skin tests with HE white extract and determination of serum specific IgE against HE white. Predictive decision points for a positive outcome of food challenges were calculated through receiver operating characteristic (ROC) analysis for HE white using IgE concentration, weal size and end-point titration (EPT). OFC was positive (Sampson's score >or=3) in 20/47 children (42.5%). The area under the ROC curve obtained with the EPT method was significantly bigger than the one obtained by measuring IgE-specific antibodies (0.99 vs. 0.83, P<0.05) and weal size (0.99 vs. 0.88, P<0.05). The extract's dilution that successfully discriminated a positive from a negative OFC (sensitivity 95%, specificity 100%) was 1 : 256, corresponding to a concentration of 5.9 microg/mL of ovotransferrin, 22.2 microg/mL of ovalbumin, and 1.4 microg/mL of lysozyme. EPT is a promising approach to optimize the use of skin prick tests and to predict the outcome of OFC with HE in children. Further studies are needed to test whether this encouraging finding can be extended to other populations and food allergens.

Protective Skins for Composite Airliners

Science.gov (United States)

Johnson, Vicki S.; Boone, Richard L.; Jones, Shannon; Pendse, Vandana; Hayward, Greg

2014-01-01

Traditional composite aircraft structures are designed for load bearing and then overdesigned for impact damage and hot humid environments. Seeking revolutionary improvement in the performance and weight of composite structures, Cessna Aircraft Company, with sponsorship from the NASA Fundamental Aeronautics Program/Subsonic Fixed Wing Project, has developed and tested a protective skin concept which would allow the primary composite structure to carry only load and would meet the impact, hot and humid, and other requirements through protective skins. A key requirement for the protective skins is to make any impact damage requiring repair visible. Testing from the first generation of skins helped identify the most promising materials which were used in a second generation of test articles. This report summarizes lessons learned from the first generation of protective skins, the design and construction of the second-generation test articles, test results from the second generation for impact, electromagnetic effects, aesthetics and smoothing, thermal, and acoustic (for the first time), and an assessment of the feasibility of the protective skin concept.

Staphylococcus aureus α-toxin modulates skin host response to viral infection.

Science.gov (United States)

Bin, Lianghua; Kim, Byung Eui; Brauweiler, Anne; Goleva, Elena; Streib, Joanne; Ji, Yinduo; Schlievert, Patrick M; Leung, Donald Y M

2012-09-01

Patients with atopic dermatitis (AD) with a history of eczema herpeticum have increased staphylococcal colonization and infections. However, whether Staphylococcus aureus alters the outcome of skin viral infection has not been determined. We investigated whether S aureus toxins modulated host response to herpes simplex virus (HSV) 1 and vaccinia virus (VV) infections in normal human keratinocytes (NHKs) and in murine infection models. NHKs were treated with S aureus toxins before incubation of viruses. BALB/c mice were inoculated with S aureus 2 days before VV scarification. Viral loads of HSV-1 and VV were evaluated by using real-time PCR, a viral plaque-forming assay, and immunofluorescence staining. Small interfering RNA duplexes were used to knockdown the gene expression of the cellular receptor of α-toxin, a disintegrin and metalloprotease 10 (ADAM10). ADAM10 protein and α-toxin heptamers were detected by using Western blot assays. We demonstrate that sublytic staphylococcal α-toxin increases viral loads of HSV-1 and VV in NHKs. Furthermore, we demonstrate in vivo that the VV load is significantly greater (P skin inoculated with an α-toxin-producing S aureus strain compared with murine skin inoculated with the isogenic α-toxin-deleted strain. The viral enhancing effect of α-toxin is mediated by ADAM10 and is associated with its pore-forming property. Moreover, we demonstrate that α-toxin promotes viral entry in NHKs. The current study introduces the novel concept that staphylococcal α-toxin promotes viral skin infection and provides a mechanism by which S aureus infection might predispose the host toward disseminated viral infections. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Effects of methylglyoxal bis(guanylhydrazone) on tumour and skin responses to hyperthermia in mice

International Nuclear Information System (INIS)

Miyakoshi, J.; Oda, W.; Inagaki, C.; Hiraoka, M.; Takahashi, M.; Abe, M.

1984-01-01

Effects of methylglyoxal bis(guanylhydrazone) (MGBG) on tumour and skin responses to hyperthermia (42degC) were examined in C3H mice. MGBG (50 mg/kg) was administered intraperitoneally to mice 4 hours before hyperthermic treatment. The tumour (FM3A) growth time was elongated by an amount dependent on the exposure time of treatment at 42degC (60, 90 and 120 min). Pre-treatment of mice with MGBG (50 mg/kg, i.p.) apparently further lengthened the tumour growth time after treatment at 42degC. No significant damage of foot skin was caused by 42degC hyperthermia. Pre-treatment with MGBG did not make the foot skin susceptible to the heating. From these findings, it can be considered that MGBG or related less-toxic compounds may have a clinical advantage for the mild (42degC) hyperthermic treatment in cancer therapy. (author)

Effects of methylglyoxal bis(guanylhydrazone) on tumour and skin responses to hyperthermia in mice

Energy Technology Data Exchange (ETDEWEB)

Miyakoshi, J.; Oda, W.; Inagaki, C. (Kyoto Coll. of Pharmacy (Japan)); Hiraoka, M.; Takahashi, M.; Abe, M. (Kyoto Univ. (Japan). Faculty of Medicine)

1984-09-01

Effects of methylglyoxal bis(guanylhydrazone) (MGBG) on tumour and skin responses to hyperthermia (42degC) were examined in C3H mice. MGBG (50 mg/kg) was administered intraperitoneally to mice 4 hours before hyperthermic treatment. The tumour (FM3A) growth time was elongated by an amount dependent on the exposure time of treatment at 42degC (60, 90 and 120 min). Pre-treatment of mice with MGBG (50 mg/kg, i.p.) apparently further lengthened the tumour growth time after treatment at 42degC. No significant damage of foot skin was caused by 42degC hyperthermia. Pre-treatment with MGBG did not make the foot skin susceptible to the heating. From these findings, it can be considered that MGBG or related less-toxic compounds may have a clinical advantage for the mild (42degC) hyperthermic treatment in cancer therapy.

Arsenic transformation predisposes human skin keratinocytes to UV-induced DNA damage yet enhances their survival apparently by diminishing oxidant response

International Nuclear Information System (INIS)

Sun Yang; Kojima, Chikara; Chignell, Colin; Mason, Ronald; Waalkes, Michael P.

2011-01-01

Inorganic arsenic and UV, both human skin carcinogens, may act together as skin co-carcinogens. We find human skin keratinocytes (HaCaT cells) are malignantly transformed by low-level arsenite (100 nM, 30 weeks; termed As-TM cells) and with transformation concurrently undergo full adaptation to arsenic toxicity involving reduced apoptosis and oxidative stress response to high arsenite concentrations. Oxidative DNA damage (ODD) is a possible mechanism in arsenic carcinogenesis and a hallmark of UV-induced skin cancer. In the current work, inorganic arsenite exposure (100 nM) did not induce ODD during the 30 weeks required for malignant transformation. Although acute UV-treatment (UVA, 25 J/cm 2 ) increased ODD in passage-matched control cells, once transformed by arsenic to As-TM cells, acute UV actually further increased ODD (> 50%). Despite enhanced ODD, As-TM cells were resistant to UV-induced apoptosis. The response of apoptotic factors and oxidative stress genes was strongly mitigated in As-TM cells after UV exposure including increased Bcl2/Bax ratio and reduced Caspase-3, Nrf2, and Keap1 expression. Several Nrf2-related genes (HO-1, GCLs, SOD) showed diminished responses in As-TM cells after UV exposure consistent with reduced oxidant stress response. UV-exposed As-TM cells showed increased expression of cyclin D1 (proliferation gene) and decreased p16 (tumor suppressor). UV exposure enhanced the malignant phenotype of As-TM cells. Thus, the co-carcinogenicity between UV and arsenic in skin cancer might involve adaptation to chronic arsenic exposure generally mitigating the oxidative stress response, allowing apoptotic by-pass after UV and enhanced cell survival even in the face of increased UV-induced oxidative stress and increased ODD. - Highlights: → Arsenic transformation adapted to UV-induced apoptosis. → Arsenic transformation diminished oxidant response. → Arsenic transformation enhanced UV-induced DNA damage.

Compositional analysis and physicochemical and mechanical testing of tanned rabbit skins

Directory of Open Access Journals (Sweden)

M.L. R. Sousa

2016-09-01

Full Text Available Chemical composition and physicochemical and mechanical parameters of New Zealand White rabbit tanned skin were evaluated. Skin samples from 70-d-old males, in natura and semi-finished, were collected for evaluation. The in natura treatment comprise skins without any processing, while semi-finished treatment comprise skins after soaking, fleshing, liming, de-liming, purging, degreasing, pickling, tanning, neutralising, re-tanning and dyeing, followed by oiling, drying, stretching and softening. After tanning, samples from the dorsal and flank regions were removed for tensile and physicochemical testing in the longitudinal and transverse directions. A split plot design was used with plot treatments (leather regions: R1=dorsal and R2=flank and subplots directions (S1=longitudinal and S2=transversal, using 10 examples per treatment. At the end of processing, the leather analysis revealed low moisture (31.76%, protein (46.48% and fat content (24.95%, and a high ash content (8.58%. Leather presented a pH of 4.9 and contained 2.0% chromium oxide, 25.5% extractable substances in dichloromethane, and these characteristics were coupled with a higher tensile strength (10.84 N/mm2 in the dorsal region. However, samples in the same region proved to have higher elasticity (64.57% in the longitudinal direction, although there was no difference in the progressive tearing analysis (21.07-23.50 N/mm. Overall, our analyses suggest that, in this case, the tanned leather product does not have sufficient resistance for application in clothing production.

Breathable and Stretchable Temperature Sensors Inspired by Skin

Science.gov (United States)

Chen, Ying; Lu, Bingwei; Chen, Yihao; Feng, Xue

2015-06-01

Flexible electronics attached to skin for healthcare, such as epidermal electronics, has to struggle with biocompatibility and adapt to specified environment of skin with respect to breath and perspiration. Here, we report a strategy for biocompatible flexible temperature sensors, inspired by skin, possessing the excellent permeability of air and high quality of water-proof by using semipermeable film with porous structures as substrate. We attach such temperature sensors to underarm and forearm to measure the axillary temperature and body surface temperature respectively. The volunteer wears such sensors for 24 hours with two times of shower and the in vitro test shows no sign of maceration or stimulation to the skin. Especially, precise temperature changes on skin surface caused by flowing air and water dropping are also measured to validate the accuracy and dynamical response. The results show that the biocompatible temperature sensor is soft and breathable on the human skin and has the excellent accuracy compared to mercury thermometer. This demonstrates the possibility and feasibility of fully using the sensors in long term body temperature sensing for medical use as well as sensing function of artificial skin for robots or prosthesis.

Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

Energy Technology Data Exchange (ETDEWEB)

Ogami, M; Kulkarni, R; Wang, H; Reif, R; Wang, R K [University of Washington, Department of Bioengineering, Seattle, Washington 98195 (United States)

2014-08-31

We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing. (laser biophotonics)

Laser speckle contrast imaging of skin blood perfusion responses induced by laser coagulation

Science.gov (United States)

Ogami, M.; Kulkarni, R.; Wang, H.; Reif, R.; Wang, R. K.

2014-08-01

We report application of laser speckle contrast imaging (LSCI), i.e., a fast imaging technique utilising backscattered light to distinguish such moving objects as red blood cells from such stationary objects as surrounding tissue, to localise skin injury. This imaging technique provides detailed information about the acute perfusion response after a blood vessel is occluded. In this study, a mouse ear model is used and pulsed laser coagulation serves as the method of occlusion. We have found that the downstream blood vessels lacked blood flow due to occlusion at the target site immediately after injury. Relative flow changes in nearby collaterals and anastomotic vessels have been approximated based on differences in intensity in the nearby collaterals and anastomoses. We have also estimated the density of the affected downstream vessels. Laser speckle contrast imaging is shown to be used for highresolution and fast-speed imaging for the skin microvasculature. It also allows direct visualisation of the blood perfusion response to injury, which may provide novel insights to the field of cutaneous wound healing.

Skin-safe photothermal therapy enabled by responsive release of acid-activated membrane-disruptive polymer from polydopamine nanoparticle upon very low laser irradiation.

Science.gov (United States)

Zhu, Rui; Gao, Feng; Piao, Ji-Gang; Yang, Lihua

2017-07-25

How to ablate tumor without damaging skin is a challenge for photothermal therapy. We, herein, report skin-safe photothermal cancer therapy provided by the responsive release of acid-activated hemolytic polymer (aHLP) from the photothermal polydopamine (PDA) nanoparticle upon irradiation at very low dosage. Upon skin-permissible irradiation (via an 850 nm laser irradiation at the power density of 0.4 W cm -2 ), the nanoparticle aHLP-PDA generates sufficient localized-heat to bring about mild hyperthermia treatment and consequently, responsively sheds off the aHLP polymer from its PDA nanocore; this leads to selective cytotoxicity to cancer cells under the acidic conditions of the extracellular microenvironment of tumor. As a result, our aHLP-PDA nanoparticle upon irradiation at a low dosage effectively inhibits tumor growth without damaging skin, as demonstrated using animal models. Effective in mitigating the otherwise inevitable skin damage in tumor photothermal therapy, the nanosystem reported herein offers an efficient pathway towards skin-safe photothermal therapy.

Low-pressure sequential compression of lower limbs enhances forearm skin blood flow.

Science.gov (United States)

Amah, Guy; Voicu, Sebastian; Bonnin, Philippe; Kubis, Nathalie

2016-12-01

We investigated whether forearm skin blood flow could be improved when a multilayer pulsatile inflatable suit was applied at a low pressure to the lower limbs and abdomen. We hypothesized that a non-invasive purely mechanical stimulation of the lower limbs could induce remote forearm blood flow modifications. The pulsatile suit induced a sequential compartmentalized low compression (65 mmHg), which was synchronized with each diastole of the cardiac cycle with each phase evolving centripetally (lower limbs to abdomen). Modifications of the forearm skin blood flow were continuously recorded by laser Doppler flowmetry (LDF) at baseline and during the pulsatile suit application. Endothelium-dependent and endothelium-independent vasodilations of the forearm skin microcirculation were measured by LDF in response to a local transdermal iontophoretic application of acetylcholine (ACh-test) and to hyperthermia (hyperT- test). Twenty-four healthy volunteers, 12 men and 12 women (43±14 years) were included in the study. LDF responses increased 1) under pulsatile suit (97±106%, p.

Course of Skin Symptoms and Quality of Life in Children Referred for Patch Testing

DEFF Research Database (Denmark)

Simonsen, Anne B; Sommerlund, Mette; Deleuran, Mette

2015-01-01

Children are patch tested in the same manner as adults, but little has been done to establish whether positive or negative findings influence the course of skin symptoms. To uncover the course of skin symptoms and the impact of persistent eczema on life quality in paediatric patients referred...... to follow-up. Among patients without atopic dermatitis, 23.5% reported to suffer from chronic eczema. Persistent eczema increased the risk of severe impairment of life quality. Our findings indicate a significant risk of childhood eczema becoming chronic and affecting life quality considerably. Patch...

Use of a smart phone based thermo camera for skin prick allergy testing: a feasibility study (Conference Presentation)

Science.gov (United States)

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.

Proficiency testing of skin prick testers as part of a quality assurance system

DEFF Research Database (Denmark)

Malling, Hans-Jørgen; Allesen-Holm, Pernille; Karved, Lisbeth Sys

2016-01-01

BACKGROUND: Skin prick test is an important diagnostic procedure in clinical allergy but documentation of the quality is often missing. METHODS: We describe a proficiency system to evaluate staff members in relation to the international recommended reproducibility in terms of coefficient...... of variation (CV 0.85) based on blinded octuplicate histamine testing using histamine 3, 10, 30 and 100 mg/ml. RESULTS: Fourteen trained allergy nurses participated in the proficiency testing. More than 95 % of the nurses, generated coefficient of variation...

Measurement of erythema and tanning responses in human skin using a tri-stimulus colorimeter.

Science.gov (United States)

Seitz, J C; Whitmore, C G

1988-01-01

A 'Minolta Tri-Stimulus Colorimeter II' was evaluated for obtaining objective measurements of early changes in erythema and tanning. The meter showed a subtle, continuous transition between the primary erythematous response and the delayed tanning of skin which was below the visual threshold for detection. Thereafter, the a* (redness) value of the meter showed a significant linear correlation with the dermatologist's perception of erythema while the b* (yellow) value showed a significant correlation with the perception of tanning. This capability of the tri-stimulus colorimeter to simultaneously evaluate the hue and saturation of skin color affords an improved opportunity to quantitate the transition from erythema to tanning without subjective bias.

Food Sensitivity in Children with Acute Urticaria in Skin Prick Test: Single Center Experience

Directory of Open Access Journals (Sweden)

Hatice Eke Gungor

2015-11-01

Full Text Available Aim: Families of children with acute urticaria often think that there is food allergy in children with urticaria and insist for skin tests. In this study, it was aimed to determine whether skin prick tests are necessary in cases presented with acute urticaria, in whom other causes of acute urticaria are excluded. Material and Method: A test panel involving cow milk, egg white, wheat, hazelnut, peanut, soybean, walnut, sesame, and tuna fish antigens was applied to the children presented with acute urticaria between 1 August 2013 and 1 August 2014, in whom other causes of acute urticaria were excluded and suspected food allergy was reported by parents. Results: Overall, 574 children aged 1-14 years were included to the study. Of the patients, sensitization against at least one food antigen was detected in 22.3% (128/574 of the patients. This rate was found to be 31.9% among those younger than 3 years, while 19.3% in those older than 3 years. Overall, sensitization rates against food allergen in panel were as follows: egg white, 7.3%; wheat, 3.3%; cow milk, 2.7%,; sesame, 2.8%; hazelnut, 2.4%; soybean, 2.3%; peanut, 1.9%, walnut, 1.6%; tuna fish, 1.6%. In general, the history of patients wasn%u2019t compatible with food sensitization detected. Discussion: Sensitization to food allergens is infrequent in children presented with acute urticaria, particularly among those older than 3 years despite expressions of parent and skin prick tests seems to be unnecessary unless strongly suggestive history is present.

Epidermal Rac1 regulates the DNA damage response and protects from UV-light-induced keratinocyte apoptosis and skin carcinogenesis

Science.gov (United States)

Deshmukh, Jayesh; Pofahl, Ruth; Haase, Ingo

2017-01-01

Non-melanoma skin cancer (NMSC) is the most common type of cancer. Increased expression and activity of Rac1, a small Rho GTPase, has been shown previously in NMSC and other human cancers; suggesting that Rac1 may function as an oncogene in skin. DMBA/TPA skin carcinogenesis studies in mice have shown that Rac1 is required for chemically induced skin papilloma formation. However, UVB radiation by the sun, which causes DNA damage, is the most relevant cause for NMSC. A potential role of Rac1 in UV-light-induced skin carcinogenesis has not been investigated so far. To investigate this, we irradiated mice with epidermal Rac1 deficiency (Rac1-EKO) and their controls using a well-established protocol for long-term UV-irradiation. Most of the Rac1-EKO mice developed severe skin erosions upon long-term UV-irradiation, unlike their controls. These skin erosions in Rac1-EKO mice healed subsequently. Surprisingly, we observed development of squamous cell carcinomas (SCCs) within the UV-irradiation fields. This shows that the presence of Rac1 in the epidermis protects from UV-light-induced skin carcinogenesis. Short-term UV-irradiation experiments revealed increased UV-light-induced apoptosis of Rac1-deficient epidermal keratinocytes in vitro as well as in vivo. Further investigations using cyclobutane pyrimidine dimer photolyase transgenic mice revealed that the observed increase in UV-light-induced keratinocyte apoptosis in Rac1-EKO mice is DNA damage dependent and correlates with caspase-8 activation. Furthermore, Rac1-deficient keratinocytes showed reduced levels of p53, γ-H2AX and p-Chk1 suggesting an attenuated DNA damage response upon UV-irradiation. Taken together, our data provide direct evidence for a protective role of Rac1 in UV-light-induced skin carcinogenesis and keratinocyte apoptosis probably through regulating mechanisms of the DNA damage response and repair pathways. PMID:28277539

Epidermal Rac1 regulates the DNA damage response and protects from UV-light-induced keratinocyte apoptosis and skin carcinogenesis.

Science.gov (United States)

Deshmukh, Jayesh; Pofahl, Ruth; Haase, Ingo

2017-03-09

Non-melanoma skin cancer (NMSC) is the most common type of cancer. Increased expression and activity of Rac1, a small Rho GTPase, has been shown previously in NMSC and other human cancers; suggesting that Rac1 may function as an oncogene in skin. DMBA/TPA skin carcinogenesis studies in mice have shown that Rac1 is required for chemically induced skin papilloma formation. However, UVB radiation by the sun, which causes DNA damage, is the most relevant cause for NMSC. A potential role of Rac1 in UV-light-induced skin carcinogenesis has not been investigated so far. To investigate this, we irradiated mice with epidermal Rac1 deficiency (Rac1-EKO) and their controls using a well-established protocol for long-term UV-irradiation. Most of the Rac1-EKO mice developed severe skin erosions upon long-term UV-irradiation, unlike their controls. These skin erosions in Rac1-EKO mice healed subsequently. Surprisingly, we observed development of squamous cell carcinomas (SCCs) within the UV-irradiation fields. This shows that the presence of Rac1 in the epidermis protects from UV-light-induced skin carcinogenesis. Short-term UV-irradiation experiments revealed increased UV-light-induced apoptosis of Rac1-deficient epidermal keratinocytes in vitro as well as in vivo. Further investigations using cyclobutane pyrimidine dimer photolyase transgenic mice revealed that the observed increase in UV-light-induced keratinocyte apoptosis in Rac1-EKO mice is DNA damage dependent and correlates with caspase-8 activation. Furthermore, Rac1-deficient keratinocytes showed reduced levels of p53, γ-H2AX and p-Chk1 suggesting an attenuated DNA damage response upon UV-irradiation. Taken together, our data provide direct evidence for a protective role of Rac1 in UV-light-induced skin carcinogenesis and keratinocyte apoptosis probably through regulating mechanisms of the DNA damage response and repair pathways.

Identification of common allergens for united airway disease by skin prick test

Directory of Open Access Journals (Sweden)

Vikas Deep Mishra

2016-01-01

Full Text Available Objective: Identification of common allergens by skin prick test in patients of united airway disease. Materials and Methods: Skin prick test was performed in 60 patients of United Airway Disease to identify the common allergens. A total of 62 allergens consisting of 36 types of pollen, 5 fungi, 4 insects, 8 type of dusts, 4 dander, 3 fabrics, Dust mite and Parthenium leaves were tested. Result: Most common allergens were Dust mite (60% followed by Parthenium leaves (45%, insects (18.75%, pollen (14.81%, dust allergens (8.51%, fabrics (8.33%, fungi (5.66%, dander (5%. Most common insect allergens were cockroach (female (30%, cockroach (male (23.33%. Common pollens were Ricinus communis (28.33%, Amaranthus spinosus (28.33%, Parthenium hysterophorus (26.66%, Eucalyptus tereticornis (26.66% and Cynodon dactylon (25%. Common dust allergens were house dust (21.66%, paper dust (11.66% and cotton mill dust (10%. Among fabrics kapok cotton (13.33% showed maximum positivity. Among fungi Aspergillus fumigatus (10% followed by A. niger (6.66% were most common. In animal dander group common ones were cat dander followed by dog dander. Conclusion: In conclusion it can be said that the knowledge drawn by above study will help to treat patients by immunotherapy or avoidance strategy.

QSAR Study of Skin Sensitization Using Local Lymph Node Assay Data

Directory of Open Access Journals (Sweden)

Eugene Demchuk

2004-01-01

Full Text Available Abstract: Allergic Contact Dermatitis (ACD is a common work-related skin disease that often develops as a result of repetitive skin exposures to a sensitizing chemical agent. A variety of experimental tests have been suggested to assess the skin sensitization potential. We applied a method of Quantitative Structure-Activity Relationship (QSAR to relate measured and calculated physical-chemical properties of chemical compounds to their sensitization potential. Using statistical methods, each of these properties, called molecular descriptors, was tested for its propensity to predict the sensitization potential. A few of the most informative descriptors were subsequently selected to build a model of skin sensitization. In this work sensitization data for the murine Local Lymph Node Assay (LLNA were used. In principle, LLNA provides a standardized continuous scale suitable for quantitative assessment of skin sensitization. However, at present many LLNA results are still reported on a dichotomous scale, which is consistent with the scale of guinea pig tests, which were widely used in past years. Therefore, in this study only a dichotomous version of the LLNA data was used. To the statistical end, we relied on the logistic regression approach. This approach provides a statistical tool for investigating and predicting skin sensitization that is expressed only in categorical terms of activity and nonactivity. Based on the data of compounds used in this study, our results suggest a QSAR model of ACD that is based on the following descriptors: nDB (number of double bonds, C-003 (number of CHR3 molecular subfragments, GATS6M (autocorrelation coefficient and HATS6m (GETAWAY descriptor, although the relevance of the identified descriptors to the continuous ACD QSAR has yet to be shown. The proposed QSAR model gives a percentage of positively predicted responses of 83% on the training set of compounds, and in cross validation it correctly identifies 79% of

The skin immune system (SIS): distribution and immunophenotype of lymphocyte subpopulations in normal human skin

NARCIS (Netherlands)

Bos, J. D.; Zonneveld, I.; Das, P. K.; Krieg, S. R.; van der Loos, C. M.; Kapsenberg, M. L.

1987-01-01

The complexity of immune response-associated cells present in normal human skin was recently redefined as the skin immune system (SIS). In the present study, the exact immunophenotypes of lymphocyte subpopulations with their localizations in normal human skin were determined quantitatively. B cells

The value of Tzanck smear test in diagnosis of erosive, vesicular, bullous, and pustular skin lesions.

Science.gov (United States)

Durdu, Murat; Baba, Mete; Seçkin, Deniz

2008-12-01

Tzanck smear is generally used for the diagnosis of the pemphigus group of autoimmune bullous diseases and mucocutaneous herpesvirus infections. There are only a few studies in the literature investigating its diagnostic value. We aimed to investigate Tzanck smear findings and to determine the diagnostic value of this test in moist (erosive, vesicular, bullous, and pustular) skin lesions. We also aimed to develop an algorithmic approach for the diagnosis of these types of skin lesions according to the Tzanck smear findings. Samples were stained with May-Grünwald-Giemsa and evaluated by the same dermatologist. In some patients, methylene blue and Gram staining or direct immunofluorescence examinations were additionally performed. In all of the study cases, after the evaluation of clinical and laboratory findings (including, when appropriate, potassium hydroxide examination; viral serology; bacterial and fungal cultures; histopathology; direct and indirect immunofluorescence; patch testing), the definite diagnosis was established. We also determined the sensitivity and the specificity of certain Tzanck smear findings. Tzanck smear was performed in a total of 400 patients with moist skin lesions. The sensitivities of multinucleated giant cells and acantholytic cells in herpetic infections, dyskeratotic acantholytic cells and cocci in bullous impetigo, pseudohyphae in candidiasis, acantholytic cells in pemphigus and more than 10 tadpole cells (magnification x100) in spongiotic dermatitis were 84.7%, 92%, 100%, 100%, and 81.5%, respectively. Because Tzanck smears were evaluated by the same dermatologist, no comment could be made regarding the interobserver reliability of this test and how the level of experience with this technique might affect the results. Also, the sensitivity and the specificity of Tzanck smear test findings for certain diseases could not be calculated because of an insufficient number of patients. The Tzanck smear test is an inexpensive, useful

Dramatic response to nivolumab in xeroderma pigmentosum skin tumor.

Science.gov (United States)

Chambon, Fanny; Osdoit, Sophie; Bagny, Kelly; Moro, Anne; Nguyen, Jacqueline; Réguerre, Yves

2018-02-01

We report the case of a 6-year-old female with xeroderma pigmentosum (XP) who developed a nonoperable scalp tumor, treated with anti-programmed cell death protein 1 (anti-PD-1) therapy (nivolumab). She presented with a sarcomatoid carcinoma of the scalp with bone lysis as well as vascular and meningeal contact. Nivolumab was initiated because it has emerged as a promising immunotherapy. We observed a dramatic tumor response with excellent tolerance. However, while on nivolumab therapy she developed two large skin melanomas and several squamous cell carcinomas, which have been resected. These results demonstrate that cancer immunotherapy in patients with XP can be impressive but complex and warrants further investigation. © 2017 Wiley Periodicals, Inc.

White matter abnormalities in skin picking disorder

DEFF Research Database (Denmark)

Grant, Jon E; Odlaug, Brian Lawrence; Hampshire, Adam

2013-01-01

Skin picking disorder (SPD) is characterized by the repetitive and compulsive picking of skin, resulting in tissue damage. Neurocognitive findings in SPD implicate difficulty with response inhibition (suppression of pre-potent motor responses). This function is dependent on the integrity of the r......Skin picking disorder (SPD) is characterized by the repetitive and compulsive picking of skin, resulting in tissue damage. Neurocognitive findings in SPD implicate difficulty with response inhibition (suppression of pre-potent motor responses). This function is dependent on the integrity...... remarkably similar to those previously reported in trichotillomania. This study adds considerable support to the notion that-in addition to the phenomenological and comorbid overlap between SPD and trichotillomania-these disorders likely share overlapping neurobiology....

Comparison of fabric skins for the simulation of sweating on thermal manikins

Science.gov (United States)

Koelblen, Barbara; Psikuta, Agnes; Bogdan, Anna; Annaheim, Simon; Rossi, René M.

2017-09-01

Sweating is an important thermoregulatory process helping to dissipate heat and, thus, to prevent overheating of the human body. Simulations of human thermo-physiological responses in hot conditions or during exercising are helpful for assessing heat stress; however, realistic sweating simulation and evaporative cooling is needed. To this end, thermal manikins dressed with a tight fabric skin can be used, and the properties of this skin should help human-like sweat evaporation simulation. Four fabrics, i.e., cotton with elastane, polyester, polyamide with elastane, and a skin provided by a manikin manufacturer (Thermetrics) were compared in this study. The moisture management properties of the fabrics have been investigated in basic tests with regard to all phases of sweating relevant for simulating human thermo-physiological responses, namely, onset of sweating, fully developed sweating, and drying. The suitability of the fabrics for standard tests, such as clothing evaporative resistance measurements, was evaluated based on tests corresponding to the middle phase of sweating. Simulations with a head manikin coupled to a thermo-physiological model were performed to evaluate the overall performance of the skins. The results of the study showed that three out of four evaluated fabrics have adequate moisture management properties with regard to the simulation of sweating, which was confirmed in the coupled simulation with the head manikin. The presented tests are helpful for comparing the efficiency of different fabrics to simulate sweat-induced evaporative cooling on thermal manikins.

Cold-induced vasoconstriction at forearm and hand skin sites: the effect of age

OpenAIRE

Kingma, B.R.M.; Frijns, A.J.H.; Saris, W.H.M.; Steenhoven, van, A.A.; Marken Lichtenbelt, van, W.D.

2010-01-01

During mild cold exposure, elderly are at risk of hypothermia. In humans, glabrous skin at the hands is well adapted as a heat exchanger. Evidence exists that elderly show equal vasoconstriction due to local cooling at the ventral forearm, yet no age effects on vasoconstriction at hand skin have been studied. Here, we tested the hypotheses that at hand sites (a) elderly show equal vasoconstriction due to local cooling and (b) elderly show reduced response to noradrenergic stimuli. Skin perfus...

Skin barrier function

DEFF Research Database (Denmark)

2016-01-01

Renowned experts present the latest knowledge Although a very fragile structure, the skin barrier is probably one of the most important organs of the body. Inward/out it is responsible for body integrity and outward/in for keeping microbes, chemicals, and allergens from penetrating the skin. Since...... the role of barrier integrity in atopic dermatitis and the relationship to filaggrin mutations was discovered a decade ago, research focus has been on the skin barrier, and numerous new publications have become available. This book is an interdisciplinary update offering a wide range of information...... on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...

Error response test system and method using test mask variable

Science.gov (United States)

Gender, Thomas K. (Inventor)

2006-01-01

An error response test system and method with increased functionality and improved performance is provided. The error response test system provides the ability to inject errors into the application under test to test the error response of the application under test in an automated and efficient manner. The error response system injects errors into the application through a test mask variable. The test mask variable is added to the application under test. During normal operation, the test mask variable is set to allow the application under test to operate normally. During testing, the error response test system can change the test mask variable to introduce an error into the application under test. The error response system can then monitor the application under test to determine whether the application has the correct response to the error.

Is skin penetration a determining factor in skin sensitization ...

Science.gov (United States)

Summary:Background. It is widely accepted that substances that cannot penetrate through the skin will not be sensitisers. Thresholds based on relevant physicochemical parameters such as a LogKow > 1 and a MW 1 is a true requirement for sensitisation.Methods. A large dataset of substances that had been evaluated for their skin sensitisation potential, together with measured LogKow values was compiled from the REACH database. The incidence of skin sensitisers relative to non-skin sensitisers below and above the LogKow = 1 threshold was evaluated. Results. 1482 substances with associated skin sensitisation outcomes and measured LogKow values were identified. 305 substances had a measured LogKow self-evident truth borne out from the widespread misconception that the ability to efficiently penetrate the stratum corneum is a key determinant of skin sensitisation potential and potency. Using the REACH data extracted to test out the validity of common assumptions in the skin sensitization AOP. Builds on trying to develop a proof of concept IATA

Skin Potential as an Indicator of Emotion

Science.gov (United States)

Seligman, Linda

1975-01-01

The skin-potential responses of six college students were monitored while each was seen for 10 counseling sessions. Negative skin-potential responses were accompanied by feelings described as pleasant and released; positive responses were associated with unpleasant and inhibited feelings; and neutral responses were often associated with unpleasant…

The sympathetic skin response in diabetic neuropathy and its relationship to autonomic symptoms

International Nuclear Information System (INIS)

Al-Moallem, Mansour A.; Zaidan, Radwan M.; Alkali, Nura H.

2008-01-01

Objective was to examine the utility of the sympathetic skin response (SSR) as a measure of impaired autonomic function among diabetic patients in Saudi Arabia. In this case-control study, baseline SSR was obtained from 18 healthy subjects, followed by nerve conduction studies and SSR testing on a consecutive cohort of 50 diabetic patients with peripheral neuropathy. The SSR in diabetic patients was compared between those with autonomic neuropathy and those without autonomic neuropathy. This study was conducted at the King Khalid University Hospital, Riyadh, Saudi Arabia, from June 2006 to June 2007. The SSR was present in all healthy subjects and in 32 diabetic patients. Among 16 patients with autonomic neuropathy, the SSR was absent in 14 and present in 2, while 4 of 34 patients lacking evidence of autonomic neuropathy had absent SSR. Using Fisher's exact test, we found a strong association between absent SSR and autonomic neuropathy (p<0.001), however, not with age or duration of diabetes mellitus. As a diagnostic test of autonomic neuropathy, the SSR had a sensitivity of 87.5%, a specificity of 88.2%, a positive predictive value of 77.8%, and a negative predictive value of 93.7%. Absence of the SSR is a reliable indicator of autonomic neuropathy among patients with diabetes mellitus in Saudi Arabia. (author)

Prediction of skin sensitization potency using machine learning approaches.

Science.gov (United States)

Zang, Qingda; Paris, Michael; Lehmann, David M; Bell, Shannon; Kleinstreuer, Nicole; Allen, David; Matheson, Joanna; Jacobs, Abigail; Casey, Warren; Strickland, Judy

2017-07-01

The replacement of animal use in testing for regulatory classification of skin sensitizers is a priority for US federal agencies that use data from such testing. Machine learning models that classify substances as sensitizers or non-sensitizers without using animal data have been developed and evaluated. Because some regulatory agencies require that sensitizers be further classified into potency categories, we developed statistical models to predict skin sensitization potency for murine local lymph node assay (LLNA) and human outcomes. Input variables for our models included six physicochemical properties and data from three non-animal test methods: direct peptide reactivity assay; human cell line activation test; and KeratinoSens™ assay. Models were built to predict three potency categories using four machine learning approaches and were validated using external test sets and leave-one-out cross-validation. A one-tiered strategy modeled all three categories of response together while a two-tiered strategy modeled sensitizer/non-sensitizer responses and then classified the sensitizers as strong or weak sensitizers. The two-tiered model using the support vector machine with all assay and physicochemical data inputs provided the best performance, yielding accuracy of 88% for prediction of LLNA outcomes (120 substances) and 81% for prediction of human test outcomes (87 substances). The best one-tiered model predicted LLNA outcomes with 78% accuracy and human outcomes with 75% accuracy. By comparison, the LLNA predicts human potency categories with 69% accuracy (60 of 87 substances correctly categorized). These results suggest that computational models using non-animal methods may provide valuable information for assessing skin sensitization potency. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Skin Penetration Enhancement by Natural Oils for Dihydroquercetin Delivery.

Science.gov (United States)

Čižinauskas, Vytis; Elie, Nicolas; Brunelle, Alain; Briedis, Vitalis

2017-09-12

Natural oils are commonly used in topical pharmaceutical formulations as emulsifiers, stabilizers or solubility enhancers. They are presented as safe and inert components, mainly used for formulation purposes. It is confirmed that natural oils can affect the skin penetration of various substances. Fatty acids are mainly responsible for this effect. Current understanding lacks reliable scientific data on penetration of natural oils into the skin and their skin penetration enhancement potential. In the current study, fatty acid content analysis was used to determine the principal fatty acids in soybean, olive, avocado, sea-buckthorn pulp, raspberry seed and coconut oils. Time of flight secondary ion mass spectrometry bioimaging was used to determine the distribution of these fatty acids in human skin ex vivo after application of the oils. Skin penetration enhancement ratios were determined for a perspective antioxidant compound dihydroquercetin. The results demonstrated skin penetration of fatty acids from all oils tested. Only soybean and olive oils significantly increased the skin distribution of dihydroquercetin and can be used as skin penetration enhancers. However, no correlation can be determined between the fatty acids' composition and skin penetration enhancement using currently available methodological approaches. This indicates that potential chemical penetration enhancement should be evaluated during formulation of topically applied products containing natural oils.

CYCLO-OXYGENASE 2 IS PRESENT IN THE MAJORITY OF LESIONAL SKIN FROM PATIENTS WITH AUTOINMUNE BLISTERING DISEASES

Directory of Open Access Journals (Sweden)

Ana Maria Abreu Velez

2013-10-01

Full Text Available Introduction: The in situ immune response within skin biopsies from patients affected by autoimmune skin blistering diseases (ABDs is not well characterized. Aim: Based on the fact that the ABD immune response is considered an adaptive immune response, both an innate immune response and inflammation would be expected in these diseases. Our investigation investigates the presence of cyclo-oxygenase-2 (COX-2, since this enzyme is commonly involved in innate immune responses. Methods: We utilized immunohistochemistry (IHC to evaluate the presence of COX-2 in lesional skin biopsies of patients affected by ABDs. We tested 30 patients with endemic pemphigus foliaceus (EPF, 15 controls from the endemic area, and 15 biopsies from healthy controls from the USA. We also tested archival biopsies from patients with selected ABDs, including 20 patients with bullous pemphigoid, 20 with pemphigus vulgaris, 8 with pemphigus foliaceus and 12 with dermatitis herpetiformis. Results: Most ABD biopsies stained positive for COX-2 in the lesional blister and/or the dermal inflammatory infiltrate, accentuated in the upper neurovascular plexus. In BP and EPF, the COX-2 staining was also seen in the sweat glands. All controls were negative. Conclusions: We document that COX-2 is expressed in lesional skin of patients with ABDs.

Design of a Biomimetic Skin for an Octopus-Inspired Robot - Part Ⅰ: Characterising Octopus Skin

Institute of Scientific and Technical Information of China (English)

Jinping Hou; Richard H. C. Bonser; George Jeronimidis

2011-01-01

Octopus skin samples were tested under quasi-static and scissor cutting conditions to measure the in-plane material properties and fracture toughness. Samples from all eight arms of one octopus were tested statically to investigate how properties vary from arm to arm. Another nine octopus skins were measured to study the influence of body mass on skin properties. Influence of specimen location on skin mechanical properties was also studied. Material properties of skin, i.e. the Young's modulus, ultimate stress, failure strain and fracture toughness have been plotted against the position of skin along the length of arm or body. Statistical studies were carried out to help analyzing experimental data obtained. Results of this work will be used as guidelines for the design and development of artificial skins for an octopus-inspired robot.

Expectancy, False Galvanic Skin Response Feedback, and Systematic Desensitization in the Modification of Phobic Behavior

Science.gov (United States)

Lick, John

1975-01-01

This study compared systematic desensitization and two pseudotherapy manipulations with and without false galvanic skin response feedback after every session suggesting improvement in the modification of intense snake and spider fear. The results indicated no consistent differences between the three treatment groups. (Author)

Digital dermoscopy to determine skin melanin index as an objective indicator of skin pigmentation

Directory of Open Access Journals (Sweden)

Sara Majewski

2016-04-01

Full Text Available Clinical assessment of skin photosensitivity is subjectively determined by erythema and tanning responses to sunlight recalled by the subject, alternatively known as Fitzpatrick Skin Phototype (SPT. Responses may be unreliable due to recall bias, subjective bias by clinicians and subjects, and lack of cultural sensitivity of the questions. Analysis of red-green-blue (RGB color spacing of digital images may provide an objective determination of SPT. This paper presents the studies to assess the melanin index (MI, as determined by RGB images obtained by both standard digital camera as well as by videodermoscope, and to correlate the MI with SPT based upon subjects’ verbal responses to standardized questions administered by a dermatologist.A sample of subjects representing all SPTs I–VI was selected. Both the digital camera and videodermoscope were calibrated at standard illumination, light source and white balance. Images of constitutive skin of the upper ventral arm were taken of each subject using both instruments.The studies showed that 58 subjects (20 M, 38 F were enrolled in the study (mean age: 47 years; range: 20–89, stratified to skin phototype I–VI. MI obtained by using both digital camera and videodermoscope increased significantly as the SPT increased p = 0.004 and p < 0.0001, respectively and positively correlated with dermatologist-assessed SPT (Spearman correlation, r = 0.48 and r = 0.84, respectively.Digital imaging can quantify melanin content in order to quantitatively approximate skin pigmentation in all skin phototypes including Type VI skin. This methodology holds promise as a simple, non-invasive, rapid and objective approach to reliably determine skin phototype and, with further investigation, may prove to be both practical and useful in the prediction of skin cancer risk.

Dendritic cells: biology of the skin

NARCIS (Netherlands)

Toebak, M.J.; Gibbs, S.; Bruynzeel, D.P.; Scheper, R.J.; Rustemeyer, T.

2009-01-01

Allergic contact dermatitis results from a T-cell-mediated, delayed-type hypersensitivity immune response induced by allergens. Skin dendritic cells (DCs) play a central role in the initiation of allergic skin responses. Following encounter with an allergen, DCs become activated and undergo

Metabolic and redox barriers in the skin exposed to drugs and xenobiotics.

Science.gov (United States)

Korkina, Liudmila

2016-01-01

Growing exposure of human skin to environmental and occupational hazards, to numerous skin care/beauty products, and to topical drugs led to a biomedical concern regarding sustainability of cutaneous chemical defence that is essential for protection against intoxication. Since skin is the largest extra-hepatic drug/xenobiotic metabolising organ where redox-dependent metabolic pathways prevail, in this review, publications on metabolic processes leading to redox imbalance (oxidative stress) and its autocrine/endocrine impact to cutaneous drug/xenobiotic metabolism were scrutinised. Chemical and photo-chemical skin barriers contain metabolic and redox compartments: their protective and homeostatic functions. The review will examine the striking similarity of adaptive responses to exogenous chemical/photo-chemical stressors and endogenous toxins in cutaneous metabolic and redox system; the role(s) of xenobiotics/drugs and phase II enzymes in the endogenous antioxidant defence and maintenance of redox balance; redox regulation of interactions between metabolic and inflammatory responses in skin cells; skin diseases sharing metabolic and redox problems (contact dermatitis, lupus erythematosus, and vitiligo) Due to exceptional the redox dependence of cutaneous metabolic pathways and interaction of redox active metabolites/exogenous antioxidants with drug/xenobiotic metabolism, metabolic tests of topical xenobiotics/drugs should be combined with appropriate redox analyses and performed on 3D human skin models.

Synergistic skin heat shock protein expression in response to combined laser treatment with a diode laser and ablative fractional lasers.

Science.gov (United States)

Paasch, Uwe; Sonja, Grunewald; Haedersdal, Merete

2014-06-01

Diode laser-based skin heating has been shown to minimise scars by interfering with wound healing responses through the induction of heat shock proteins (HSP). HSP are also induced after ablative fractional laser (AFXL) wound healing. AFXL itself is highly recommended for scar treatment. Therefore, the sequential combination of both modalities may produce superior outcomes. The aim of this study was to examine the pretreatment effects of a diode laser before AFXL on wound healing responses in terms of HSP up-regulation in an in vitro model. Immediate responses and responses on days 1, 3 or 6 post-procedure were studied in an in vitro porcine skin model (n = 240). Untreated samples served as control. Immunohistochemical investigation (Hsp70) was performed in all untreated controls, diode laser-, AFXL-, and in diode laser + AFXL-treated samples. Hsp70 was shown to be up-regulated by all interventions between days 1 and 6 after interventions. The largest effect was caused by the combination of a diode laser and an AFXL procedure. Diode laser exposure induces a skin HSP response that can be further enhanced by sequential AFXL treatment. Clinical studies are necessary to investigate the dose response of HSP on scar formation and refine suitable laser exposure settings.

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

Science.gov (United States)

2015-09-01

members of this committee who have their kids at one time or another wearing body armor in theater, either Iraq or Afghanistan. And that includes... YouTube has pictures of Dragon Skin body armor testing on the Internet and Wikipedia has posted a carefully documented description of the history of

Behavior of Skin Friction of Piles subjected to Top-downward and ...

African Journals Online (AJOL)

In situ results of Osterberg cell load test and the conventional static compression load test are compared. Finite Element Method (FEM) is used to study the effects of changes in boundary conditions, mechanism of pile-soil interaction and the accompanying change in soil stress, which are responsible for the difference in skin ...

Testing and Analysis of the Peeling of Medical Adhesives From Human Skin

OpenAIRE

Karwoski, Alicia Corrine

2003-01-01

The analysis of peeling tape or a bandage from skin is a challenging problem. Skin is a very complex material made of many layers with anisotropic material properties. Adhesives that bond tapes or patches to skin must attach to skin through moisture and skin movement, but then be removed with little skin trauma. A computer model of peeling from skin apparently has not been developed previously. With experiments and the application of mechanics, research was conducted to analyze adhesion to sk...

Response-surface models for deterministic effects of localized irradiation of the skin by discrete {beta}/{gamma} -emitting sources

Energy Technology Data Exchange (ETDEWEB)

Scott, B.R.

1995-12-01

Individuals who work at nuclear reactor facilities can be at risk for deterministic effects in the skin from exposure to discrete {Beta}- and {gamma}-emitting ({Beta}{gamma}E) sources (e.g., {Beta}{gamma}E hot particles) on the skin or clothing. Deterministic effects are non-cancer effects that have a threshold and increase in severity as dose increases (e.g., ulcer in skin). Hot {Beta}{gamma}E particles are {sup 60}Co- or nuclear fuel-derived particles with diameters > 10 {mu}m and < 3 mm and contain at least 3.7 kBq (0.1 {mu}Ci) of radioactivity. For such {Beta}{gamma}E sources on the skin, it is the beta component of the dose that is most important. To develop exposure limitation systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for evaluating the risk of deterministic effects of localized {Beta} irradiation of the skin. The purpose of this study was to develop dose-rate and irradiated-area dependent, response-surface models for evaluating risks of significant deterministic effects of localized irradiation of the skin by discrete {Beta}{gamma}E sources and to use modeling results to recommend approaches to limiting occupational exposure to such sources. The significance of the research results as follows: (1) response-surface models are now available for evaluating the risk of specific deterministic effects of localized irradiation of the skin; (2) modeling results have been used to recommend approaches to limiting occupational exposure of workers to {Beta} radiation from {Beta}{gamma}E sources on the skin or on clothing; and (3) the generic irradiated-volume, weighting-factor approach to limiting exposure can be applied to other organs including the eye, the ear, and organs of the respiratory or gastrointestinal tract and can be used for both deterministic and stochastic effects.

Response-surface models for deterministic effects of localized irradiation of the skin by discrete β/γ -emitting sources

International Nuclear Information System (INIS)

Scott, B.R.

1995-01-01

Individuals who work at nuclear reactor facilities can be at risk for deterministic effects in the skin from exposure to discrete Β- and γ-emitting (ΒγE) sources (e.g., ΒγE hot particles) on the skin or clothing. Deterministic effects are non-cancer effects that have a threshold and increase in severity as dose increases (e.g., ulcer in skin). Hot ΒγE particles are 60 Co- or nuclear fuel-derived particles with diameters > 10 μm and < 3 mm and contain at least 3.7 kBq (0.1 μCi) of radioactivity. For such ΒγE sources on the skin, it is the beta component of the dose that is most important. To develop exposure limitation systems that adequately control exposure of workers to discrete ΒγE sources, models are needed for systems that adequately control exposure of workers to discrete ΒγE sources, models are needed for evaluating the risk of deterministic effects of localized Β irradiation of the skin. The purpose of this study was to develop dose-rate and irradiated-area dependent, response-surface models for evaluating risks of significant deterministic effects of localized irradiation of the skin by discrete ΒγE sources and to use modeling results to recommend approaches to limiting occupational exposure to such sources. The significance of the research results as follows: (1) response-surface models are now available for evaluating the risk of specific deterministic effects of localized irradiation of the skin; (2) modeling results have been used to recommend approaches to limiting occupational exposure of workers to Β radiation from ΒγE sources on the skin or on clothing; and (3) the generic irradiated-volume, weighting-factor approach to limiting exposure can be applied to other organs including the eye, the ear, and organs of the respiratory or gastrointestinal tract and can be used for both deterministic and stochastic effects

Exogenous melatonin administration modifies cutaneous vasoconstrictor response to whole body skin cooling in humans.

Science.gov (United States)

Aoki, Ken; Zhao, Kun; Yamazaki, Fumio; Sone, Ryoko; Alvarez, Guy E; Kosiba, Wojciech A; Johnson, John M

2008-03-01

Humans and other diurnal species experience a fall in internal temperature (T(int)) at night, accompanied by increased melatonin and altered thermoregulatory control of skin blood flow (SkBF). Also, exogenous melatonin induces a fall in T(int), an increase in distal skin temperatures and altered control of the cutaneous active vasodilator system, suggesting an effect of melatonin on the control of SkBF. To test whether exogenous melatonin also affects the more tonically active vasoconstrictor system in glabrous and nonglabrous skin during cooling, healthy males (n = 9) underwent afternoon sessions of whole body skin temperature (T(sk)) cooling (water-perfused suits) after oral melatonin (Mel; 3 mg) or placebo (Cont). Cutaneous vascular conductance (CVC) was calculated from SkBF (laser Doppler flowmetry) and non-invasive blood pressure. Baseline T(int) was lower in Mel than in Cont (P forearm CVC was first significantly reduced at T(sk) of 34.33 +/- 0.01 degrees C (P forearm CVC in Mel was significantly less than in Cont at T(sk) of 32.66 +/- 0.01 degrees C and lower (P < 0.05). In Mel, palmar CVC was significantly higher than in Cont above T(sk) of 33.33 +/- 0.01 degrees C, but not below. Thus exogenous melatonin blunts reflex vasoconstriction in nonglabrous skin and shifts vasoconstrictor system control to lower T(int). It provokes vasodilation in glabrous skin but does not suppress the sensitivity to falling T(sk). These findings suggest that by affecting the vasoconstrictor system, melatonin has a causal role in the nocturnal changes in body temperature and its control.

Implicit Recognition of Familiar and Unfamiliar Faces in Schizophrenia: A Study of the Skin Conductance Response in Familiarity Disorders

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Aurely Ameller

2017-09-01

Full Text Available ObjectiveFamiliarity is a subjective sensation that contributes to person recognition. This process is described as an emotion-based memory-trace of previous meetings and could be disrupted in schizophrenia. Consequently, familiarity disorders could be involved in the impaired social interactions observed in patients with schizophrenia. Previous studies have primarily focused on famous people recognition. Our aim was to identify underlying features, such as emotional disturbances, that may contribute to familiarity disorders in schizophrenia. We hypothesize that patients with familiarity disorders will exhibit a lack of familiarity that could be detected by a flattened skin conductance response (SCR.MethodThe SCR was recorded to test the hypothesis that emotional reactivity disturbances occur in patients with schizophrenia during the categorization of specific familiar, famous and unknown faces as male or female. Forty-eight subjects were divided into the following 3 matched groups with 16 subjects per group: control subjects, schizophrenic people with familiarity disorder, and schizophrenic people without familiarity disorders.ResultsEmotional arousal is reflected by the skin conductance measures. The control subjects and the patients without familiarity disorders experienced a differential emotional response to the specific familiar faces compared with that to the unknown faces. Nevertheless, overall, the schizophrenic patients without familiarity disorders showed a weaker response across conditions compared with the control subjects. In contrast, the patients with familiarity disorders did not show any significant differences in their emotional response to the faces, regardless of the condition.ConclusionOnly patients with familiarity disorders fail to exhibit a difference in emotional response between familiar and non-familiar faces. These patients likely emotionally process familiar faces similarly to unknown faces. Hence, the lower

Sympathetic skin responses in patients with hyperthyroidism.

Science.gov (United States)

Gozke, E; Ozyurt, Z; Dortcan, N; Ore, O; Kocer, A; Ozer, E

2007-01-01

The aim of this study was to investigate the disorders of sympathetic nervous system in patients with hyperthyroidism using sympathetic skin response (SSR). Twenty-two newly diagnosed cases with hyperthyroidism were included in the study. The results were compared with those of 20 healthy controls. SSR was recorded with the contralateral electrical stimulation of the median nerve (of the upper extremities) and tibial nerve (of the lower extremities) with active electrodes placed on palms and soles and reference electrodes attached on the dorsal aspects of hands and feet. Ages of the cases with hyperthyroidism and controls ranged between 15-65 years (mean: 46.7 +/- 15.0 years) and 24-62 years (mean: 39.6 +/- 9.8 years) respectively (p > 0.05). In all the control subjects SSR could be obtained, while from the lower extremities of 4 cases with hyperthyroidism (18.0%) SSR could not be elicited. Mean SSR latencies of lower extremities were found significantly longer than control group (p nervous system involvement in cases with hyperthyroidism.

Analysis of Double Skin Composite Slabs

Directory of Open Access Journals (Sweden)

Husain M. Husain

2018-03-01

Full Text Available This paper deals with finite element modeling of the ultimate load behavior of double skin composite (DSC slabs. In a DSC slab, shear connectors in the form of nut bolt technique studs are used to transfer shear between the outer skin made of steel plates and the concrete core. The current study is based on finite element analysis using ANSYS Version 11 APDL release computer program. Experimental programmes were carried out by the others, two simply supported DSC beams were tested until failure under a concentrated load applied at the center. These test specimens were analyzed by the finite element method and the analyses have shown that these slabs displayed a high degree of flexural characteristics, ultimate strength, and ductility. The close agreement has been observed between the finite element and experimental results for ultimate loads and load–deflection responses. The finite element model was thus found to be capable of predicting the behavior of DSC slabs accurately.

The effect of pregnancy on paternal skin allograft survival

Institute of Scientific and Technical Information of China (English)

无

2009-01-01

Elucidation of maternal-fetal tolerance mechanisms clarifies the role of regulatory T cells (Treg) in transplant tolerance. This study aim to investigate the effect of pregnancy on paternal skin allograft survival. Flow cytometry techniques, mixed lymphocytes reaction (MLR), PCR, real-time PCR and skin transplantation were key methods. Treg increased significantly from 4.2% before pregnancy to peak at 6.8% day 8 after pregnancy. Both heme oxygenase-1 (HO-1) and indoleamine 2,3-dioxygenase (IDO) mRNA express high in placenta while low in spleen (P<0.05). Although Treg increased during pregnancy, and splenocytes from the pregnant mice showed lower MLR response toward the paternal stimulator, single time pregnancy showed no significant protective effect on paternal skin allograft survival in the tested condition.

Positive Skin Test or Specific IgE to Penicillin Does Not Reliably Predict Penicillin Allergy

DEFF Research Database (Denmark)

Tannert, Line Kring; Mørtz, Charlotte G; Skov, Per Stahl

2017-01-01

INTRODUCTION: According to guidelines, patients are diagnosed with penicillin allergy if skin test (ST) result or specific IgE (s-IgE) to penicillin is positive. However, the true sensitivity and specificity of these tests are presently not known. OBJECTIVE: To investigate the clinical relevance...... of a positive ST result and positive s-IgE and to study the reproducibility of ST and s-IgE. METHODS: A sample of convenience of 25 patients with positive penicillin ST results, antipenicillin s-IgE results, or both was challenged with their culprit penicillin. Further 19 patients were not challenged......-IgE measured (T0), and then skin tested and had s-IgE measured 4 weeks later (T1). RESULTS: Only 9 (36%) of 25 were challenge positive. There was an increased probability of being penicillin allergic if both ST result and s-IgE were positive at T0. Positive ST result or positive s-IgE alone did not predict...

Supplementation with Eskimo Skin Care improves skin elasticity in women. A pilot study.

Science.gov (United States)

Segger, Dörte; Matthies, Andreas; Saldeen, Tom

2008-01-01

To investigate the question of whether supplementation with an oral oil formulation rich in natural stable fish oil can alter skin elasticity, transepidermal water loss (TEWL), and skin roughness in healthy women. Twenty-four healthy women aged 40-60 years participated in a single-blind randomized trial for testing the effect of a proprietary oral supplement for skin nutrition (Eskimo Skin Care) on skin elasticity, TEWL, and skin roughness. Skin elasticity was measured by an optical cutometer, TEWL by a water-loss module based upon the vapour gradient principle, and skin roughness with a three-dimensional microtopography imaging system. Skin elasticity increased by 10% after 3 months of treatment with the supplement, a statistically significant increase in comparison with the control group (p=0.0298). There was a trend, though not statistically significant, towards a positive influence on the skin's barrier function. No effect on the skin roughness was observed. Eskimo Skin Care, an oral preparation rich in natural stable fish oil, can improve skin elasticity.

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

Science.gov (United States)

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. Copyright © 2013 Elsevier Inc. All rights reserved.

Skin reactions amongst Greek endodontists: a national questionnaire survey.

Science.gov (United States)

Zarra, T; Lambrianidis, T

2015-04-01

To investigate amongst Greek endodontists in the past 5 years the prevalence, aetiologic factors, severity and treatment for skin reactions. One hundred and 47 endodontists met the inclusion criteria and were invited to participate in the survey. Participants were asked for personal/professional data, prevalence, aetiologic factors, symptoms, severity and treatment for skin reactions in the past 5 years. The type of gloves used and frequency of hand washing as well as information on history of atopy and eczema were also recorded. Data were analysed using chi-square test and independent samples t-test. The level of significance was set at P = 0.05. The response rate was 84%. Skin reactions were reported by 32.5% of participants. Hands were the body part most frequently affected (66% of cases); glove powder accounted for 73% of skin reactions. Medical care was sought by 28.2% of the affected participants. Endodontists with a history of atopy (P skin reactions. Replacement of powdered latex gloves with powder-free or vinyl/nitrile gloves, avoidance of potential allergens and use of pharmaceutical ointments were adopted by 48.7%, 23.1% and 2.6% of the affected endodontists, respectively, to manage skin reactions. Approximately one-third of participants reported skin reactions. History of atopy and dermal eczema as well as gender was significantly associated with such reactions. The use of powder-free latex gloves instead of powdered ones was the measure most frequently adopted to manage reactions. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Relationship between skin temperature and muscle activation during incremental cycle exercise.

Science.gov (United States)

Priego Quesada, Jose I; Carpes, Felipe P; Bini, Rodrigo R; Salvador Palmer, Rosario; Pérez-Soriano, Pedro; Cibrián Ortiz de Anda, Rosa M

2015-02-01

While different studies showed that better fitness level adds to the efficiency of the thermoregulatory system, the relationship between muscular effort and skin temperature is still unknown. Therefore, the present study assessed the relationship between neuromuscular activation and skin temperature during cycle exercise. Ten physically active participants performed an incremental workload cycling test to exhaustion while neuromuscular activations were recorded (via surface electromyography - EMG) from rectus femoris, vastus lateralis, biceps femoris and gastrocnemius medialis. Thermographic images were recorded before, immediately after and 10 min after finishing the cycling test, at four body regions of interest corresponding to the muscles where neuromuscular activations were monitored. Frequency band analysis was conducted to assess spectral properties of EMG signals in order to infer on priority in recruitment of motor units. Significant inverse relationship between changes in skin temperature and changes in overall neuromuscular activation for vastus lateralis was observed (r0.7 and p<0.01). Participants with larger overall activation and reduced low frequency component for vastus lateralis activation presented a better adaptive response of their thermoregulatory system by showing fewer changes in skin temperature after incremental cycling test. Copyright © 2014 Elsevier Ltd. All rights reserved.

Localization of sclerotic-type chronic graft-vs-host disease to sites of skin injury: potential insight into the mechanism of isomorphic and isotopic responses.

Science.gov (United States)

Martires, Kathryn J; Baird, Kristin; Citrin, Deborah E; Hakim, Fran T; Pavletic, Steven Z; Cowen, Edward W

2011-09-01

The mechanisms responsible for the variable manifestations of chronic cutaneous graft-vs-host disease (cGVHD) are poorly understood. Localization of sclerotic-type chronic graft-vs-host disease to sites of skin injury (isomorphic and isotopic responses), a recognized phenomenon in morphea, suggests a potential common pathway between cGVHD and other sclerotic skin conditions. Four cases of sclerotic-type cGVHD developed at the site of disparate skin injuries (ionizing radiotherapy, repeated needle sticks, central catheter site, and varicella-zoster virus infection). We review the spectrum of previously reported cases of sclerotic and nonsclerotic cGVHD relating to external forces on the skin. Localization of sclerotic-type cGVHD may occur after many types of skin injury, including UV and ionizing radiotherapy, needle sticks, viral infection, and pressure or friction. Recognition of this phenomenon may be helpful for the early diagnosis of sclerotic disease. Recent insights into the immunological consequences of minor skin injury may provide important clues to the underlying pathogenesis of cGVHD-mediated skin disease.

Evaluation of the effect of Dardia Lipo Line on skin inflammation induced by surfactants using the repeated open-application test.

Science.gov (United States)

Ortonne, J-P; Queille-Roussel, C

2007-09-01

Medical skin care products are topical preparations with mainly moisturizing properties. A new line of medical skin products with an excellent tolerability profile and improved hydration for dry skin has been developed, but beneficial effects have not yet been investigated on damaged skin. To investigate if these products maintain barrier function and hydration status, improve subjective symptoms due to irritant contact dermatitis and to prove their tolerability on damaged skin. Single-centre, blinded, randomized, controlled study in 20 healthy Caucasian women. 5% sodium lauryl sulphate solution was used to induce skin irritation. Two sites on the inside surface of both forearms of each subject were treated daily for 5 days (irritation period). Lipo Cream, Lipo Milk (water-in-oil emulsions) and Lipo Ointment (water-free formulation) were applied twice daily to three of the four test sites on days 1-5. The fourth site was used as a control. Visual readings, subjective symptom assessments, transepidermal water loss (TEWL) and colorimetric measurements, corneometry and skin microrelief macrophotographies were done on days 1-6. On day 6, TEWL was increased vs baseline on all sites; however, TEWL with Lipo Cream or Lipo Ointment was significantly lower than control. At day 6, skin capacitance was 94%, 100% and 85% of baseline value for the cream, milk and ointment, respectively, versus 72% for control. All test products were well tolerated. Lipo Line products showed both protective properties against epidermal dysfunction and significant hydrating effect.

Studies on the prevalence of leishmanin skin test positivity in the Baringo District, Rift Valley, Kenya

NARCIS (Netherlands)

Schaefer, K. U.; Kurtzhals, J. A.; Kager, P. A.; Gachihi, G. S.; Gramiccia, M.; Kagai, J. M.; Sherwood, J. A.; Muller, A. S.

1994-01-01

The leishmanin skin test (LST) was applied in 26 clusters of an average of 97 individuals in Baringo District, Kenya. These clusters were centered around recent cases of visceral leishmaniasis (VL). Of 2,411 individuals tested, 254 (10.5%, 155 males and 99 females) had a positive reaction. Among

Radiophosphorus (32P)-test on precancerosis and malignant tumors of the skin

International Nuclear Information System (INIS)

Biersack, H.J.; Rodermund, O.E.; Meurin, G.; Winkler, C.; Bonn Univ.

1976-01-01

In 21 patients with a variety of skin tumors (squamous cell carcinomas, malignant melanomas, basal cell epitheliomas and mycosis fungoides) or precancerous lesions (Bowen's disease, actinic keratosis, junctional nevus cell nevus) the radioactive phosphorus uptake test demonstrates a sign ficantly increased concentration of P 32 in those tumors. There were no false negative tests. The possibility of differentiation of malignant melanoma from benign nevus cell nevus and the early recognition of cutaneous metastases is described. Furthermore recurrence of previously irradiated or excised basal cell epitheliomas can be detected without a biopsy. No hematological side-effects were observed. (orig.) [de

Inflammatory response, parasite load and AgNOR expression in ear skin of symptomatic and asymptomatic Leishmania (Leishmania chagasi infected dogs

Directory of Open Access Journals (Sweden)

Verçosa BLA

2011-01-01

Full Text Available The skin has an important role in the transmission of visceral leishmaniasis (VL as the infection pathway in dogs. To better characterize the inflammatory response of intact skin in VL, sixty infected dogs (30 symptomatic and 30 asymptomatic and six non-infected controls were studied. Diagnosis of visceral leishmaniasis was confirmed by RIFI and ELISA; direct visualization of the parasite in bone marrow aspirate; imprints of popliteal lymph nodes, spleen, liver and skin; culture in NNN-phase liquid Schneider's medium; and PCR (performed only in the ear skin. Amastigote forms of the parasite in intact skin were found only in symptomatic dogs. Inflammatory infiltrates were observed in all groups, varying from intense and/or moderate in symptomatic to discrete and/or negligible in asymptomatic and control animals. Parasite load was associated with the intensity of the inflammatory response and with clinical manifestations in canine visceral leishmaniasis. AgNOr as active transcription markers were expressed in inflammatory cells and within apoptotic bodies in all groups, including controls, with no statistical difference. Therefore, cell activation and transcription do occur in both symptomatic and asymptomatic canine visceral leishmaniasis and may result in more necrosis and inflammation or in apoptosis and less symptoms, depending on the parasite load.

Tuberculin skin testing in patients with HIV infection: limited benefit of reduced cutoff values

NARCIS (Netherlands)

Cobelens, Frank G.; Egwaga, Saidi M.; van Ginkel, Tessa; Muwinge, Hemed; Matee, Mecky I.; Borgdorff, Martien W.

2006-01-01

BACKGROUND: When determining eligibility for isoniazid preventive therapy of human immunodeficiency virus (HIV)-infected patients, the cutoff value of the tuberculin skin test (TST) is often reduced from an induration of 10 mm in diameter to one of 5 mm in diameter to compensate for loss of

Differential gene expression profiling of mouse skin after sulfur mustard exposure: Extended time response and inhibitor effect

International Nuclear Information System (INIS)

Gerecke, Donald R.; Chen Minjun; Isukapalli, Sastry S.; Gordon, Marion K.; Chang, Y.-C.; Tong Weida; Androulakis, Ioannis P.; Georgopoulos, Panos G.

2009-01-01

Sulfur mustard (HD, SM), is a chemical warfare agent that within hours causes extensive blistering at the dermal-epidermal junction of skin. To better understand the progression of SM-induced blistering, gene expression profiling for mouse skin was performed after a single high dose of SM exposure. Punch biopsies of mouse ears were collected at both early and late time periods following SM exposure (previous studies only considered early time periods). The biopsies were examined for pathological disturbances and the samples further assayed for gene expression profiling using the Affymetrix microarray analysis system. Principal component analysis and hierarchical cluster analysis of the differently expressed genes, performed with ArrayTrack showed clear separation of the various groups. Pathway analysis employing the KEGG library and Ingenuity Pathway Analysis (IPA) indicated that cytokine-cytokine receptor interaction, cell adhesion molecules (CAMs), and hematopoietic cell lineage are common pathways affected at different time points. Gene ontology analysis identified the most significantly altered biological processes as the immune response, inflammatory response, and chemotaxis; these findings are consistent with other reported results for shorter time periods. Selected genes were chosen for RT-PCR verification and showed correlations in the general trends for the microarrays. Interleukin 1 beta was checked for biological analysis to confirm the presence of protein correlated to the corresponding microarray data. The impact of a matrix metalloproteinase inhibitor, MMP-2/MMP-9 inhibitor I, against SM exposure was assessed. These results can help in understanding the molecular mechanism of SM-induced blistering, as well as to test the efficacy of different inhibitors

Adaptive technique for matching the spectral response in skin lesions' images

International Nuclear Information System (INIS)

Pavlova, P; Borisova, E; Avramov, L; Pavlova, E

2015-01-01

The suggested technique is a subsequent stage for data obtaining from diffuse reflectance spectra and images of diseased tissue with a final aim of skin cancer diagnostics. Our previous work allows us to extract patterns for some types of skin cancer, as a ratio between spectra, obtained from healthy and diseased tissue in the range of 380 – 780 nm region. The authenticity of the patterns depends on the tested point into the area of lesion, and the resulting diagnose could also be fixed with some probability. In this work, two adaptations are implemented to localize pixels of the image lesion, where the reflectance spectrum corresponds to pattern. First adapts the standard to the personal patient and second – translates the spectrum white point basis to the relative white point of the image. Since the reflectance spectra and the image pixels are regarding to different white points, a correction of the compared colours is needed. The latest is done using a standard method for chromatic adaptation. The technique follows the steps below: –Calculation the colorimetric XYZ parameters for the initial white point, fixed by reflectance spectrum from healthy tissue; –Calculation the XYZ parameters for the distant white point on the base of image of nondiseased tissue; –Transformation the XYZ parameters for the test-spectrum by obtained matrix; –Finding the RGB values of the XYZ parameters for the test-spectrum according sRGB; Finally, the pixels of the lesion's image, corresponding to colour from the test-spectrum and particular diagnostic pattern are marked with a specific colour

Prospective, multicenter clinical trial to validate new products for skin tests in the diagnosis of allergy to penicillin.

Science.gov (United States)

Fernández, J; Torres, M J; Campos, J; Arribas-Poves, F; Blanca, M

2013-01-01

Allergy to penicillin is the most commonly reported type of drug hypersensitivity. Diagnosis is currently confirmed using skin tests with benzylpenicillin reagents, ie, penicilloyl-polylysine (PPL) as the major determinant of benzylpenicillin and benzylpenicillin, benzylpenicilloate and benzylpenilloate as a minor determinant mixture (MDM). To synthesize and assess the diagnostic capacity of 2 new benzylpenicillin reagents in patients with immediate hypersensitivity reactions to B-lactams: benzylpenicilloyl octa-L-lysine (BP-OL) as the major determinant and benzylpenilloate (penilloate) as the minor determinant. Prospective multicenter clinical trial performed in 18 Spanish centers. Efficacy was assessed by detection of positive skin test results in an allergic population and negative skin test results in a nonallergic, drug-exposed population. Sensitivity, specificity, and negative and positive predictive values were determined. The study sample comprised 94 allergic patients: 31 (35.23%) presented anaphylaxis, 4 (4.55%) anaphylactic shock, 51 (58.04%) urticaria, and 2 (2.27%) no specific condition. The culprit 8-lactams were amoxicillin in 63 cases (71.60%), benzypencillin in 14 cases (15.89%), cephalosporins in 2 cases (2.27%), other drugs in 3 cases (3.42%), and unidentified agents in 6 cases (6.82%). The results of testing with BP-OL were positive in 46 cases (52.3%); the results of testing with penilloate were positive in 33 cases (37.5%). When both reagents were taken into consideration, sensitivity reached 61.36% and specificity 100%. Skin testing with penilloate was significantly more often negative when the interval between the reaction and the study was longer. The sensitivity of BP-OL and penilloate was 61%. Considering that amoxicillin was the culprit drug in 71% of reactions, these results indicate that most patients were allergic to the whole group of penicillins. These data support the use of benzylpenicillin determinants in the diagnosis of allergy

Facial skin blood flow responses during exposures to emotionally charged movies.

Science.gov (United States)

Matsukawa, Kanji; Endo, Kana; Ishii, Kei; Ito, Momoka; Liang, Nan

2018-03-01

The changes in regional facial skin blood flow and vascular conductance have been assessed for the first time with noninvasive two-dimensional laser speckle flowmetry during audiovisually elicited emotional challenges for 2 min (comedy, landscape, and horror movie) in 12 subjects. Limb skin blood flow and vascular conductance and systemic cardiovascular variables were simultaneously measured. The extents of pleasantness and consciousness for each emotional stimulus were estimated by the subjective rating from -5 (the most unpleasant; the most unconscious) to +5 (the most pleasant; the most conscious). Facial skin blood flow and vascular conductance, especially in the lips, decreased during viewing of comedy and horror movies, whereas they did not change during viewing of a landscape movie. The decreases in facial skin blood flow and vascular conductance were the greatest with the comedy movie. The changes in lip, cheek, and chin skin blood flow negatively correlated (P < 0.05) with the subjective ratings of pleasantness and consciousness. The changes in lip skin vascular conductance negatively correlated (P < 0.05) with the subjective rating of pleasantness, while the changes in infraorbital, subnasal, and chin skin vascular conductance negatively correlated (P < 0.05) with the subjective rating of consciousness. However, none of the changes in limb skin blood flow and vascular conductance and systemic hemodynamics correlated with the subjective ratings. The mental arithmetic task did not alter facial and limb skin blood flows, although the task influenced systemic cardiovascular variables. These findings suggest that the more emotional status becomes pleasant or conscious, the more neurally mediated vasoconstriction may occur in facial skin blood vessels.

Oncogenic Radiation Abscopal Effects In Vivo: Interrogating Mouse Skin

International Nuclear Information System (INIS)

Mancuso, Mariateresa; Leonardi, Simona; Giardullo, Paola; Pasquali, Emanuela; Tanori, Mirella; De Stefano, Ilaria; Casciati, Arianna; Naus, Christian C.; Pazzaglia, Simonetta; Saran, Anna

2013-01-01

Purpose: To investigate the tissue dependence in transmission of abscopal radiation signals and their oncogenic consequences in a radiosensitive mouse model and to explore the involvement of gap junction intercellular communication (GJIC) in mediating radiation tumorigenesis in off-target mouse skin. Methods and Materials: Patched1 heterozygous (Ptch1 +/− ) mice were irradiated at postnatal day 2 (P2) with 10 Gy of x-rays. Individual lead cylinders were used to protect the anterior two-thirds of the body, whereas the hindmost part was directly exposed to radiation. To test the role of GJICs and their major constituent connexin43 (Cx43), crosses between Ptch1 +/− and Cx43 +/− mice were similarly irradiated. These mouse groups were monitored for their lifetime, and skin basal cell carcinomas (BCCs) were counted and recorded. Early responses to DNA damage - Double Strand Breaks (DSBs) and apoptosis - were also evaluated in shielded and directly irradiated skin areas. Results: We report abscopal tumor induction in the shielded skin of Ptch1 +/− mice after partial-body irradiation. Endpoints were induction of early nodular BCC-like tumors and macroscopic infiltrative BCCs. Abscopal tumorigenesis was significantly modulated by Cx43 status, namely, Cx43 reduction was associated with decreased levels of DNA damage and oncogenesis in out-of-field skin, suggesting a key role of GJIC in transmission of oncogenic radiation signals to unhit skin. Conclusions: Our results further characterize the nature of abscopal responses and the implications they have on pathologic processes in different tissues, including their possible underlying mechanistic bases

Oncogenic Radiation Abscopal Effects In Vivo: Interrogating Mouse Skin

Energy Technology Data Exchange (ETDEWEB)

Mancuso, Mariateresa, E-mail: mariateresa.mancuso@enea.it [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Leonardi, Simona [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Giardullo, Paola; Pasquali, Emanuela [Department of Radiation Physics, Guglielmo Marconi University, Rome (Italy); Tanori, Mirella [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); De Stefano, Ilaria [Department of Radiation Physics, Guglielmo Marconi University, Rome (Italy); Casciati, Arianna [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Naus, Christian C. [Department of Cellular and Physiological Sciences, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia (Canada); Pazzaglia, Simonetta; Saran, Anna [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy)

2013-08-01

Purpose: To investigate the tissue dependence in transmission of abscopal radiation signals and their oncogenic consequences in a radiosensitive mouse model and to explore the involvement of gap junction intercellular communication (GJIC) in mediating radiation tumorigenesis in off-target mouse skin. Methods and Materials: Patched1 heterozygous (Ptch1{sup +/−}) mice were irradiated at postnatal day 2 (P2) with 10 Gy of x-rays. Individual lead cylinders were used to protect the anterior two-thirds of the body, whereas the hindmost part was directly exposed to radiation. To test the role of GJICs and their major constituent connexin43 (Cx43), crosses between Ptch1{sup +/−} and Cx43{sup +/−} mice were similarly irradiated. These mouse groups were monitored for their lifetime, and skin basal cell carcinomas (BCCs) were counted and recorded. Early responses to DNA damage - Double Strand Breaks (DSBs) and apoptosis - were also evaluated in shielded and directly irradiated skin areas. Results: We report abscopal tumor induction in the shielded skin of Ptch1{sup +/−} mice after partial-body irradiation. Endpoints were induction of early nodular BCC-like tumors and macroscopic infiltrative BCCs. Abscopal tumorigenesis was significantly modulated by Cx43 status, namely, Cx43 reduction was associated with decreased levels of DNA damage and oncogenesis in out-of-field skin, suggesting a key role of GJIC in transmission of oncogenic radiation signals to unhit skin. Conclusions: Our results further characterize the nature of abscopal responses and the implications they have on pathologic processes in different tissues, including their possible underlying mechanistic bases.

Response of Human Skin to Aesthetic Scarification

Science.gov (United States)

Gabriel, Vincent A.; McClellan, Elizabeth A.; Scheuermann, Richard H.

2014-01-01

This study was undertaken to investigate changes in RNA expression in previously healthy adult human skin following thermal injury induced by contact with hot metal that was undertaken as part of aesthetic scarification, a body modification practice. Subjects were recruited to have pre-injury skin and serial wound biopsies performed. 4 mm punch biopsies were taken prior to branding and 1 hour, 1 week, and 1, 2 and 3 months post injury. RNA was extracted and quality assured prior to the use of a whole-genome based bead array platform to describe expression changes in the samples using the pre-injury skin as a comparator. Analysis of the array data was performed using k-means clustering and a hypergeometric probability distribution without replacement and corrections for multiple comparisons were done. Confirmatory q-PCR was performed. Using a k of 10, several clusters of genes were shown to co-cluster together based on Gene Ontology classification with probabilities unlikely to occur by chance alone. OF particular interest were clusters relating to cell cycle, proteinaceous extracellular matrix and keratinization. Given the consistent expression changes at one week following injury in the cell cycle cluster, there is an opportunity to intervene early following burn injury to influence scar development. PMID:24582755

A SKIN TEST FOR DETECTING GROUP C HEMOLYTIC STREPTOCOCCAL INFECTION CAUSING EPIZOOTIC LYMPHADENITIS IN GUINEA PIGS : APPLICATIONS IN SELECTING BREEDING STOCK.

Science.gov (United States)

Moen, J K

1936-09-30

1. A skin test with a crude bacterial extract prepared from group C (Lancefield) hemolytic streptococci was used as a means of detecting possible carriers of the streptococcus causing epizootic lymphadenitis in guinea pigs. A positive test similar to a positive tuberculin reaction was considered presumptive evidence of present or recent infection with this streptococcus. 2. 20 positive reactors were found in 330 supposedly normal guinea pigs. 3. 195 negatively reacting animals were used as a breeding stock which yielded 1,296 progeny over a period of 15 months. None of the breeding stock or their progeny showed evidence of spontaneous lymphadenitis. Skin tests of 100 of the progeny were all negative. 4. The use of this skin test as a means of obtaining guinea pig breeding stock free of the streptococcus causing spontaneous lymphadenitis is suggested.

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

Science.gov (United States)

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

2015-12-01

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

Melatonin, mitochondria, and the skin.

Science.gov (United States)

Slominski, Andrzej T; Zmijewski, Michal A; Semak, Igor; Kim, Tae-Kang; Janjetovic, Zorica; Slominski, Radomir M; Zmijewski, Jaroslaw W

2017-11-01

The skin being a protective barrier between external and internal (body) environments has the sensory and adaptive capacity to maintain local and global body homeostasis in response to noxious factors. An important part of the skin response to stress is its ability for melatonin synthesis and subsequent metabolism through the indolic and kynuric pathways. Indeed, melatonin and its metabolites have emerged as indispensable for physiological skin functions and for effective protection of a cutaneous homeostasis from hostile environmental factors. Moreover, they attenuate the pathological processes including carcinogenesis and other hyperproliferative/inflammatory conditions. Interestingly, mitochondria appear to be a central hub of melatonin metabolism in the skin cells. Furthermore, substantial evidence has accumulated on the protective role of the melatonin against ultraviolet radiation and the attendant mitochondrial dysfunction. Melatonin and its metabolites appear to have a modulatory impact on mitochondrion redox and bioenergetic homeostasis, as well as the anti-apoptotic effects. Of note, some metabolites exhibit even greater impact than melatonin alone. Herein, we emphasize that melatonin-mitochondria axis would control integumental functions designed to protect local and perhaps global homeostasis. Given the phylogenetic origin and primordial actions of melatonin, we propose that the melatonin-related mitochondrial functions represent an evolutionary conserved mechanism involved in cellular adaptive response to skin injury and repair.

Lightning Tests on the WC-130 Research Aircraft.

Science.gov (United States)

1982-12-01

in the WC-136 tests at various times.) E- Feild Fiber Optic Test Article Sensor Transmitter (Typ)WiePr Indtuced Voltag Sensor"" *Fiber I"=Current optic...well-characterized. 5.1 Skin Current Measurements Skin current vectors were measured at five fuselage locations on the left side of the WC-130 at a...MGL-S7) which were mounted so that they sampled two orthogonal components of the skin current vector . The measured responses were then inte- grated

β-adrenergic blockade does not impair the skin blood flow sensitivity to local heating in burned and non-burned skin under neutral and hot environments in children

Science.gov (United States)

Rivas, Eric; McEntire, Serina J.; Herndon, David N.; Mlcak, Ronald P.; Suman, Oscar E.

2017-01-01

Objective Tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. Methods In a randomized double-blind study, a placebo was given to 8 burned children while propranolol was given to 13 burned children with similar characteristics (mean ± SD: 11.9±3y, 147±20cm, 45±23kg, 56±12% TBSA). Non-burned children (n=13, 11.4±3y, 152±15cm, 52±13kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and non-burned control skin under the two environmental conditions (23°C and 34°C) via laser-Doppler flowmetry. Results Resting SkBF was greater in burned and unburned skin compared to the non-burned control (main effect: skin, Pburned; 38±36 unburned vs 9±8 control %SkBFmax). No difference was found for maximal SkBF capacity to local heating between groups. Additionally, dose response curves for the sensitivity of SkBF to local heating were not different among burned or unburned skin, and non-burned control skin (EC50, P>0.05) under either condition. Conclusion Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children. PMID:28071840

Moist skin care can diminish acute radiation-induced skin toxicity

International Nuclear Information System (INIS)

Momm, F.; Weissenberger, C.; Bertelt, S.; Henke, M.

2003-01-01

Background: Radiation treatment may induce acute skin reactions. There are several methods of managing them. Validity of these methods, however, is not sufficiently studied. We therefore investigated, whether moist skin care with 3% urea lotion will reduce acute radiation skin toxicity. Patients and Methods: 88 patients with carcinomas of the head and neck undergoing radiotherapy with curative intent (mean total dose 60 Gy, range: 50-74 Gy) were evaluated weekly for acute skin reactions according to the RTOG-CTC score. In 63 patients, moist skin care with 3% urea lotion was performed. The control group consisted of 25 patients receiving conventional dry skin care. The incidence of grade I, II, and III reactions and the radiation dose at occurrence of a particular reaction were determined and statistically analyzed using the log-rank test. The dose-time relations of individual skin reactions are described. Results: At some point of time during radiotherapy, all patients suffered from acute skin reactions grade I, > 90% from grade II reactions. 50% of patients receiving moist skin care experienced grade I reactions at 26 Gy as compared to 22 Gy in control patients (p = 0.03). Grade II reactions occurred at 51 Gy versus 34 Gy (p = 0.006). Further, 22% of the patients treated with moist skin care suffered from acute skin toxicity grade III as compared to 56% of the controls (p = 0.0007). Conclusion: Moist skin care with 3% urea lotion delays the occurrence and reduces the grade of acute skin reactions in percutaneously irradiated patients with head and neck tumors. (orig.)

Skin care products can aggravate epidermal function: studies in a murine model suggest a pathogenic role in sensitive skin

OpenAIRE

Li, Z; Hu, L; Elias, PM; Man, M-Q

2018-01-01

Sensitive skin is defined as a spectrum of unpleasant sensations in response to a variety of stimuli. However, only some skin care products provoke cutaneous symptoms in individuals with sensitive skin. Hence, it would be useful to identify products that could provoke cutaneous symptoms in individuals with sensitive skin.To assess whether vehicles, as well as certain branded skin care products, can alter epidermal function following topical applications to normal mouse skin.Following topical ...

Skin denervation and its clinical significance in late-stage chronic kidney disease.

Science.gov (United States)

Chao, Chi-Chao; Wu, Vin-Cent; Tan, Chun-Hsiang; Wang, Yi-Mei; Tseng, Ming-Tsung; Wu, Pei-Chen; Lin, Yea-Huey; Lin, Whei-Min; Wu, Kwan-Dun; Hsieh, Sung-Tsang

2011-02-01

To investigate the skin innervation and its clinical significance in late-stage chronic kidney disease (CKD). Case series. National Taiwan University Hospital, Taipei, Taiwan. Forty consecutive nondiabetic patients with late-stage CKD (14 female and 26 male; mean [SD] age, 60.7 [12.3] years), including 2 cases with stage 3 CKD, 6 with stage 4 CKD, and 32 with stage 5 CKD, ie, end-stage kidney disease. Clinical evaluation of neurological deficits, nerve conduction study, autonomic function tests, and a 3-mm-diameter skin biopsy specimen taken from the distal leg. Quantitation of epidermal innervation, parameters of nerve conduction study, R-R interval variability, and sympathetic skin response. Clinically, 21 patients (52.5%) were symptomatic with paresthesia over the limbs or autonomic symptoms. The intraepidermal nerve fiber (IENF) density was markedly reduced in patients with CKD compared with age- and sex-matched controls (mean [SD], 2.8 [2.0] vs 8.6 [2.8] fibers/mm; P Skin denervation was observed in 27 patients (67.5%). Fifteen patients (37.5%) had abnormalities on nerve conduction studies, and 29 patients (72.5%) had abnormal results on autonomic function tests. By analysis with multiple regression models, the IENF density was negatively correlated with the duration of renal disease (P = .02). Additionally, the R-R interval variability at rest was linearly correlated with the IENF density (P = .02) and the absence of sympathetic skin responses at the soles was associated with reduced IENF density (P = .03). Small-fiber sensory and autonomic neuropathies constitute the major form of neuropathy in late-stage CKD. Furthermore, skin denervation was associated with the duration of renal disease.

Fractionated laser resurfacing corrects the inappropriate UVB response in geriatric skin

OpenAIRE

Spandau, Dan F; Lewis, Davina A.; Somani, Ally-Khan; Travers, Jeffrey B.

2012-01-01

Non-melanoma skin cancer is a disease primarily afflicting geriatric patients as evidenced by the fact that 80% of all non-melanoma skin cancers are diagnosed in patients over the age of 60 years. As such, geriatric skin responds to cancer-inducing UVB irradiation in a manner that allows the establishment of tumor cells. Currently, the only effective treatment for non-melanoma skin cancer is the removal of the tumors after they appear, indicating the need for a more cost-effective prophylacti...

Anatomy of the Skin and the Pathogenesis of Nonmelanoma Skin Cancer.

Science.gov (United States)

Losquadro, William D

2017-08-01

Skin is composed of the epidermis, dermis, and adnexal structures. The epidermis is composed of 4 layers-the stratums basale, spinosum, granulosum, and corneum. The dermis is divided into a superficial papillary dermis and deeper reticular dermis. Collagen and elastin within the reticular dermis are responsible for skin tensile strength and elasticity, respectively. The 2 most common kinds of nonmelanoma skin cancers are basal cell and squamous cell carcinoma. Both are caused by a host of environmental and genetic factors, although UV light exposure is the single greatest predisposing factor. Copyright © 2017 Elsevier Inc. All rights reserved.

Optimisation of gelatin extraction from Unicorn leatherjacket (Aluterus monoceros) skin waste: response surface approach.

Science.gov (United States)

Hanjabam, Mandakini Devi; Kannaiyan, Sathish Kumar; Kamei, Gaihiamngam; Jakhar, Jitender Kumar; Chouksey, Mithlesh Kumar; Gudipati, Venkateshwarlu

2015-02-01

Physical properties of gelatin extracted from Unicorn leatherjacket (Aluterus monoceros) skin, which is generated as a waste from fish processing industries, were optimised using Response Surface Methodology (RSM). A Box-Behnken design was used to study the combined effects of three independent variables, namely phosphoric acid (H3PO4) concentration (0.15-0.25 M), extraction temperature (40-50 °C) and extraction time (4-12 h) on different responses like yield, gel strength and melting point of gelatin. The optimum conditions derived by RSM for the yield (10.58%) were 0.2 M H3PO4 for 9.01 h of extraction time and hot water extraction of 45.83 °C. The maximum achieved gel strength and melting point was 138.54 g and 22.61 °C respectively. Extraction time was found to be most influencing variable and had a positive coefficient on yield and negative coefficient on gel strength and melting point. The results indicated that Unicorn leatherjacket skins can be a source of gelatin having mild gel strength and melting point.

Coffee polyphenols extracted from green coffee beans improve skin properties and microcirculatory function.

Science.gov (United States)

Fukagawa, Satoko; Haramizu, Satoshi; Sasaoka, Shun; Yasuda, Yuka; Tsujimura, Hisashi; Murase, Takatoshi

2017-09-01

Coffee polyphenols (CPPs), including chlorogenic acid, exert various physiological activities. The purpose of this study was to investigate the effects of CPPs on skin properties and microcirculatory function in humans. In this double-blind, placebo-controlled study, 49 female subjects with mildly xerotic skin received either a test beverage containing CPPs (270 mg/100 mL/day) or a placebo beverage for 8 weeks. The ingestion of CPPs significantly lowered the clinical scores for skin dryness, decreased transepidermal water loss, skin surface pH, and increased stratum corneum hydration and the responsiveness of skin blood flow during local warming. Moreover, the amounts of free fatty acids and lactic acid in the stratum corneum significantly increased after the ingestion of CPPs. These results suggest that an 8-week intake of CPPs improve skin permeability barrier function and hydration, with a concomitant improvement in microcirculatory function, leading to efficacy in the alleviation of mildly xerotic skin.

Experimental studies of radiation carcinogenesis in the skin: a review

International Nuclear Information System (INIS)

Coggle, J.E.; Williams, J.P.

1990-01-01

Dose and time response characteristics of cancer induction following a variety of modes and qualities of radiation exposure are reviewed in relation to rat and mouse skin studies. Despite interspecies differences, it is shown that all of the experimental data for radiogenic skin cancer, when expressed per unit area of skin, fall on a relatively narrow and well defined response curve, which is approximately two orders of magnitude more sensitive than the human skin cancer dose response. (UK)

Freqüência de positividade em teste cutâneo para aeroalérgenos Frequency of positive skin tests for airborne allergic agents

Directory of Open Access Journals (Sweden)

Ricardo Godinho

2003-12-01

Full Text Available O aumento da prevalência das rinopatias tem sido descrito na literatura médica e a rinite alérgica continua sendo a mais freqüente. O teste cutâneo é importante no diagnóstico diferencial das doenças nasais e na determinação do padrão de sensibilização da população. Esta permite a promoção de medidas de redução de exposição, sendo fundamental para o tratamento adequado da rinite alérgica. FORMA DE ESTUDO: Coorte transversal. MATERIAL E MÉTODO: Com o objetivo de determinar a freqüência de positividade no teste cutâneo para aeroalérgenos específicos, avaliamos os prontuários de 398 pacientes com sintomas nasais sugestivos de alergia ou outras queixas otorrinolaringológicas que necessitavam deste teste para esclarecimento diagnóstico. RESULTADOS: A poeira doméstica (74,9%, o dermatofagóide (58,4% e o mofo (36,5% foram os alérgenos mais freqüentes, seguidos do pêlo de cão (32,7%, gramínea (22,4%, pêlo de gato (16,9%, penas (16,4% e lã (15,6%. Apenas 3,5% com positividade para pena de periquito e 1,5% para flores. 39 pacientes (9,8% apresentaram teste cutâneo negativo, 10 (2,5% apresentaram reação ao extrato da solução e 8 (2% não reagiram à histamina. Não foram encontradas complicações à aplicação do teste. CONCLUSÃO: A poeira doméstica foi o aeroalérgeno mais freqüente. Os testes cutâneos devem ser realizados no contexto da história clínica e os resultados apresentados nos orientam para o adequado diagnóstico e tratamento das rinopatias.Medical literature has reported on the increase in the prevalence of nose diseases, and allergic rhinitis still leads the statistics. The skin test is important in the differential diagnosis of nose diseases and to determine the sensitivity pattern of the population in order to establish measures to reduce exposure. This is fundamental for adequate handling allergic rhinitis. STUDY DESIGN: Transversal cohorte. MATERIAL AND METHOD: In order to determine the

Mycobacterium tuberculosis epitope-specific interferon-g production in healthy Brazilians reactive and non-reactive to tuberculin skin test

Directory of Open Access Journals (Sweden)

Bosco Christiano Maciel da Silva

2014-12-01

Full Text Available The interferon (IFN-γ response to peptides can be a useful diagnostic marker of Mycobacterium tuberculosis (MTB latent infection. We identified promiscuous and potentially protective CD4+ T-cell epitopes from the most conserved regions of MTB antigenic proteins by scanning the MTB antigenic proteins GroEL2, phosphate-binding protein 1 precursor and 19 kDa antigen with the TEPITOPE algorithm. Seven peptide sequences predicted to bind to multiple human leukocyte antigen (HLA-DR molecules were synthesised and tested with IFN-γ enzyme-linked immunospot (ELISPOT assays using peripheral blood mononuclear cells (PBMCs from 16 Mantoux tuberculin skin test (TST-positive and 16 TST-negative healthy donors. Eighty-eight percent of TST-positive donors responded to at least one of the peptides, compared to 25% of TST-negative donors. Each individual peptide induced IFN-γ production by PBMCs from at least 31% of the TST-positive donors. The magnitude of the response against all peptides was 182 ± 230 x 106 IFN-γ spot forming cells (SFC among TST-positive donors and 36 ± 62 x 106 SFC among TST-negative donors (p = 0.007. The response to GroEL2 (463-477 was only observed in the TST-positive group. This combination of novel MTB CD4 T-cell epitopes should be tested in a larger cohort of individuals with latent tuberculosis (TB to evaluate its potential to diagnose latent TB and it may be included in ELISPOT-based IFN-γ assays to identify individuals with this condition.

Development and characterisation of an in vitro photomicronucleus test using ex vivo human skin tissue

NARCIS (Netherlands)

Reus, A.A.; Meeuwen, R.N.C. van; Vogel, N. de; Maas, W.J.M.; Krul, C.A.M.

2011-01-01

Photosafety testing is of concern for the evaluation of personal care products and pharmaceuticals. Current regulatory guidance state that photosafety should be evaluated for compounds that absorb radiation between 290 and 700 nm with relevant exposure in the skin or eyes. However, oversensitivity

Differential Gene Expression in Primary Human Skin Keratinocytes and Fibroblasts in Response to Ionizing Radiation

Science.gov (United States)

Warters, Raymond L.; Packard, Ann T.; Kramer, Gwen F.; Gaffney, David K.; Moos, Philip J.

2009-01-01

Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes to radiation. The transcriptional response of quiescent primary fibroblasts and keratinocytes exposed to from 10 cGy to 5 Gy and collected 4 h after treatment was examined. RNA was isolated and examined by microarray analysis for changes in the levels of gene expression. Exposure to ionizing radiation altered the expression of 279 genes across both cell types. Changes in RNA expression could be arranged into three main categories: (1) changes in keratinocytes but not in fibroblasts, (2) changes in fibroblasts but not in keratinocytes, and (3) changes in both. All of these changes were primarily of p53 target genes. Similar radiation-induced changes were induced in immortalized fibroblasts or keratinocytes. In separate experiments, protein was collected and analyzed by Western blotting for expression of proteins observed in microarray experiments to be overexpressed at the mRNA level. Both Q-PCR and Western blot analysis experiments validated these transcription changes. Our results are consistent with changes in the expression of p53 target genes as indicating the magnitude of cell responses to ionizing radiation. PMID:19580510

Force sensor in simulated skin and neural model mimic tactile SAI afferent spiking response to ramp and hold stimuli.

Science.gov (United States)

Kim, Elmer K; Wellnitz, Scott A; Bourdon, Sarah M; Lumpkin, Ellen A; Gerling, Gregory J

2012-07-23

The next generation of prosthetic limbs will restore sensory feedback to the nervous system by mimicking how skin mechanoreceptors, innervated by afferents, produce trains of action potentials in response to compressive stimuli. Prior work has addressed building sensors within skin substitutes for robotics, modeling skin mechanics and neural dynamics of mechanotransduction, and predicting response timing of action potentials for vibration. The effort here is unique because it accounts for skin elasticity by measuring force within simulated skin, utilizes few free model parameters for parsimony, and separates parameter fitting and model validation. Additionally, the ramp-and-hold, sustained stimuli used in this work capture the essential features of the everyday task of contacting and holding an object. This systems integration effort computationally replicates the neural firing behavior for a slowly adapting type I (SAI) afferent in its temporally varying response to both intensity and rate of indentation force by combining a physical force sensor, housed in a skin-like substrate, with a mathematical model of neuronal spiking, the leaky integrate-and-fire. Comparison experiments were then conducted using ramp-and-hold stimuli on both the spiking-sensor model and mouse SAI afferents. The model parameters were iteratively fit against recorded SAI interspike intervals (ISI) before validating the model to assess its performance. Model-predicted spike firing compares favorably with that observed for single SAI afferents. As indentation magnitude increases (1.2, 1.3, to 1.4 mm), mean ISI decreases from 98.81 ± 24.73, 54.52 ± 6.94, to 41.11 ± 6.11 ms. Moreover, as rate of ramp-up increases, ISI during ramp-up decreases from 21.85 ± 5.33, 19.98 ± 3.10, to 15.42 ± 2.41 ms. Considering first spikes, the predicted latencies exhibited a decreasing trend as stimulus rate increased, as is observed in afferent recordings. Finally, the SAI afferent's characteristic response

Syk/Src Pathway-Targeted Inhibition of Skin Inflammatory Responses by Carnosic Acid

Directory of Open Access Journals (Sweden)

Jueun Oh

2012-01-01

Full Text Available Carnosic acid (CA is a diterpene compound exhibiting antioxidative, anticancer, anti-angiogenic, anti-inflammatory, anti-metabolic disorder, and hepatoprotective and neuroprotective activities. In this study, the effect of CA on various skin inflammatory responses and its inhibitory mechanism were examined. CA strongly suppressed the production of IL-6, IL-8, and MCP-1 from keratinocyte HaCaT cells stimulated with sodium lauryl sulfate (SLS and retinoic acid (RA. In addition, CA blocked the release of nitric oxide (NO, tumor necrosis factor (TNF-α, and prostaglandin E2 (PGE2 from RAW264.7 cells activated by the toll-like receptor (TLR-2 ligands, Gram-positive bacterium-derived peptidoglycan (PGN and pam3CSK, and the TLR4 ligand, Gram-negative bacterium-derived lipopolysaccharide (LPS. CA arrested the growth of dermatitis-inducing Gram-positive and Gram-negative microorganisms such Propionibacterium acnes, Pseudomonas aeruginosa, and Staphylococcus aureus. CA also blocked the nuclear translocation of nuclear factor (NF-κB and its upstream signaling including Syk/Src, phosphoinositide 3-kinase (PI3K, Akt, inhibitor of κBα (IκBα kinase (IKK, and IκBα for NF-κB activation. Kinase assays revealed that Syk could be direct enzymatic target of CA in its anti-inflammatory action. Therefore, our data strongly suggest the potential of CA as an anti-inflammatory drug against skin inflammatory responses with Src/NF-κB inhibitory properties.