Reduced content of chloroatranol and atranol in oak moss absolute significantly reduces the elicitation potential of this fragrance material.

PubMed

Andersen, Flemming; Andersen, Kirsten H; Bernois, Armand; Brault, Christophe; Bruze, Magnus; Eudes, Hervé; Gadras, Catherine; Signoret, Anne-Cécile J; Mose, Kristian F; Müller, Boris P; Toulemonde, Bernard; Andersen, Klaus Ejner

2015-02-01

Oak moss absolute, an extract from the lichen Evernia prunastri, is a valued perfume ingredient but contains extreme allergens. To compare the elicitation properties of two preparations of oak moss absolute: 'classic oak moss', the historically used preparation, and 'new oak moss', with reduced contents of the major allergens atranol and chloroatranol. The two preparations were compared in randomized double-blinded repeated open application tests and serial dilution patch tests in 30 oak moss-sensitive volunteers and 30 non-allergic control subjects. In both test models, new oak moss elicited significantly less allergic contact dermatitis in oak moss-sensitive subjects than classic oak moss. The control subjects did not react to either of the preparations. New oak moss is still a fragrance allergen, but elicits less allergic contact dermatitis in previously oak moss-sensitized individuals, suggesting that new oak moss is less allergenic to non-sensitized individuals. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Food patch testing for irritable bowel syndrome.

PubMed

Stierstorfer, Michael B; Sha, Christopher T; Sasson, Marvin

2013-03-01

The traditional classification of irritable bowel syndrome (IBS) as a functional disorder has been challenged in recent years by evidence of ongoing low-grade gastrointestinal tract inflammation. Inflammation may alter gastrointestinal motility and thus be central to the pathogenesis of IBS. Many foods and food additives are known to cause allergic contact dermatitis. We hypothesize that allergenic foods and food additives may elicit a similar allergic reaction in the gastrointestinal tract, giving rise to symptoms suggestive of IBS. We sought to determine whether skin patch testing to a panel of foods and food additives may identify food allergens that may be responsible for symptoms of IBS. We performed skin patch testing to common allergenic foods and food additives on individuals with a history of or symptoms suggestive of IBS. We used patch test-guided avoidance diets to determine whether avoidance alleviates IBS symptoms. Thirty of the 51 study participants showed at least 1 doubtful or positive patch test result. Fourteen of the participants reported symptomatic improvement, ranging from slight to great, upon avoidance of the foods/food additives to which they reacted. Double-blind study design, inclusion of only patients with active IBS, larger sample size, more balanced gender distribution, testing of more foods/food additives, and longer duration of and more precise quantification of response to dietary avoidance are suggested for future studies. Allergic contact enteritis to ingested foods, food additives, or both may contribute to IBS symptoms. Patch testing may be useful in identifying the causative foods. Copyright © 2012 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Patch testing and cross sensitivity study of adverse cutaneous drug reactions due to anticonvulsants: A preliminary report.

PubMed

Shiny, T N; Mahajan, Vikram K; Mehta, Karaninder S; Chauhan, Pushpinder S; Rawat, Ritu; Sharma, Rajni

2017-03-26

To evaluate the utility of patch test and cross-sensitivity patterns in patients with adverse cutaneous drug reactions (ACDR) from common anticonvulsants. Twenty-four (M:F = 13:11) patients aged 18-75 years with ACDR from anticonvulsants were patch tested 3-27 mo after complete recovery using carbamazepine, phenytoin, phenobarbitone, lamotrigine, and sodium valproate in 10%, 20% and 30% conc. in pet. after informed consent. Positive reactions persisting on D3 and D4 were considered significant. Clinical patterns were exanthematous drug rash with or without systemic involvement (DRESS) in 18 (75%), Stevens-Johnsons syndrome/toxic epidermal necrolysis (SJS/TEN) overlap and TEN in 2 (8.3%) patients each, SJS and lichenoid drug eruption in 1 (4.2%) patient each, respectively. The implicated drugs were phenytoin in 14 (58.3%), carbamazepine in 9 (37.5%), phenobarbitone in 2 (8.3%), and lamotrigine in 1 (4.7%) patients, respectively. Twelve (50%) patients elicited positive reactions to implicated drugs; carbamazepine in 6 (50%), phenytoin alone in 4 (33.3%), phenobarbitone alone in 1 (8.3%), and both phenytoin and phenobarbitone in 1 (8.33%) patients, respectively. Cross-reactions occurred in 11 (92%) patients. Six patients with carbamazepine positive patch test reaction showed cross sensitivity with phenobarbitone, sodium valproate and/or lamotrigine. Three (75%) patients among positive phenytoin patch test reactions had cross reactions with phenobarbitone, lamotrigine, and/or valproate. Carbamazepine remains the commonest anticonvulsant causing ACDRs and cross-reactions with other anticonvulsants are possible. Drug patch testing appears useful in DRESS for drug imputability and cross-reactions established clinically.

Patch testing and cross sensitivity study of adverse cutaneous drug reactions due to anticonvulsants: A preliminary report

PubMed Central

Shiny, T N; Mahajan, Vikram K; Mehta, Karaninder S; Chauhan, Pushpinder S; Rawat, Ritu; Sharma, Rajni

2017-01-01

AIM To evaluate the utility of patch test and cross-sensitivity patterns in patients with adverse cutaneous drug reactions (ACDR) from common anticonvulsants. METHODS Twenty-four (M:F = 13:11) patients aged 18-75 years with ACDR from anticonvulsants were patch tested 3-27 mo after complete recovery using carbamazepine, phenytoin, phenobarbitone, lamotrigine, and sodium valproate in 10%, 20% and 30% conc. in pet. after informed consent. Positive reactions persisting on D3 and D4 were considered significant. RESULTS Clinical patterns were exanthematous drug rash with or without systemic involvement (DRESS) in 18 (75%), Stevens-Johnsons syndrome/toxic epidermal necrolysis (SJS/TEN) overlap and TEN in 2 (8.3%) patients each, SJS and lichenoid drug eruption in 1 (4.2%) patient each, respectively. The implicated drugs were phenytoin in 14 (58.3%), carbamazepine in 9 (37.5%), phenobarbitone in 2 (8.3%), and lamotrigine in 1 (4.7%) patients, respectively. Twelve (50%) patients elicited positive reactions to implicated drugs; carbamazepine in 6 (50%), phenytoin alone in 4 (33.3%), phenobarbitone alone in 1 (8.3%), and both phenytoin and phenobarbitone in 1 (8.33%) patients, respectively. Cross-reactions occurred in 11 (92%) patients. Six patients with carbamazepine positive patch test reaction showed cross sensitivity with phenobarbitone, sodium valproate and/or lamotrigine. Three (75%) patients among positive phenytoin patch test reactions had cross reactions with phenobarbitone, lamotrigine, and/or valproate. CONCLUSION Carbamazepine remains the commonest anticonvulsant causing ACDRs and cross-reactions with other anticonvulsants are possible. Drug patch testing appears useful in DRESS for drug imputability and cross-reactions established clinically. PMID:28396847

Study on cross-reactivity to the para group.

PubMed

Picardo, M; Cannistraci, C; Cristaudo, A; De Luca, C; Santucci, B

1990-01-01

In 80 patients, positive to at least one hapten of the para group (para-phenylenediamine, diaminodiphenylmethane, benzocaine, PPD mix), patch tests were carried out with freshly prepared solutions of para-phenylenediamine (PPD) and of 3 selected aromatic compounds related structurally to PPD (para-aminophenol, ortho-aminophenol, hydroquinone). The number of positive reactions correlated with the rate of decomposition of the substances as evaluated by high-pressure liquid chromatography. PPD, which was almost decomposed after 24 h, gave the highest number of positive reactions, followed by ortho-aminophenol and by para-aminophenol, while hydroquinone, which was oxidized to the extent of 35%, did not give any reactions. To evaluate if a different rate of oxidation can modify the patch test response, in the same patients and in 10 normal volunteers, tests were carried out with PPD solutions containing the oxidizing agent silver oxide (0.1%). By this procedure a significant increase in the number of positive responses was observed. The results suggest that the rate of decomposition and therefore the amount of quinone(s) generated, might be the key to eliciting patch test responses to oxidizable aromatic haptens.

Performance of a commercially available plant allergen series in the assessment of suspected occupational contact dermatitis to plants in north Indian patients.

PubMed

De, Dipankar; Khullar, Geeti; Handa, Sanjeev

2015-01-01

Parthenium hysterophorus is the leading cause of phytogenic allergic contact dermatitis in India. The Indian Standard Series currently supplied by Systopic Laboratories Ltd and manufactured by Chemotechnique Diagnostics ® contains parthenolide as the only allergen representing plant allergens. The study was conducted to assess the performance of the Chemotechnique plant series (PL-1000), consisting of 14 allergens, in patients with clinically suspected occupational contact dermatitis to plant allergens. Ninety patients were patch tested with the Chemotechnique plant series from 2011 to 2013. Demographic details, clinical diagnosis and patch test results were recorded in the contact dermatitis clinic proforma. Of 90 patients, 24 (26.7%) showed positive reactions to one or more allergens in the plant series. Positive patch tests were elicited most commonly by sesquiterpene lactone mix in 19 (78.6%) patients, followed by parthenolide in 14 (57.1%), Achillea millefolium in 10 (42.9%) and others in decreasing order. The plant allergen series prepared by Chemotechnique Diagnostics is possibly not optimal for diagnosing suspected allergic contact dermatitis to plants in north Indians. Sesquiterpene lactone mix should replace parthenolide as the plant allergen in the Indian Standard Series until relevant native plant extracts are commercially available for patch testing.

Patch testing with serial dilutions and thin-layer chromatograms of oak moss absolutes containing high and low levels of atranol and chloroatranol.

PubMed

Mowitz, Martin; Zimerson, Erik; Svedman, Cecilia; Bruze, Magnus

2013-12-01

Oak moss absolute (Evernia prunastri extract) contains a large number of substances, among them the potent allergens atranol and chloroatranol. Since 2008, their content in oak moss absolute has been restricted by the International Fragrance Association to a maximum level of 100 ppm each. To compare the elicitation capacities of a traditional (sample A) and a treated (sample B) oak moss absolute containing, in total, 27 000 and 66 ppm of atranol and chloroatranol, respectively, and to investigate reactions to components of oak moss absolute separated by thin-layer chromatography (TLC). Fifteen oak moss-allergic subjects were patch tested with serial dilutions and TLC strips of samples A and B. Fifteen subjects reacted to sample A at concentrations ≤ 2.0%, and 2 subjects reacted to sample B at 2.0% but not to lower concentrations. Among 13 subjects reacting to the TLC strip of sample A, 11 reacted to spots with retardation factor values corresponding to those of atranol and/or chloroatranol, and 11 reacted to other areas on the TLC strip. Only one subject reacted to the TLC strip of sample B. The patch test reactivity of sample B was significantly lower than that of sample A. The TLC patch tests indicate the presence of sensitizers other than atranol and chloroatranol in oak moss absolute. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contact allergy to epoxy hardeners.

PubMed

Aalto-Korte, Kristiina; Suuronen, Katri; Kuuliala, Outi; Henriks-Eckerman, Maj-Len; Jolanki, Riitta

2014-09-01

Diglycidylether of bisphenol A resin is the most important sensitizer in epoxy systems, but a minority of patients develop concomitant or solitary contact allergy to epoxy hardeners. At the Finnish Institute of Occupational Health, several in-house test substances of epoxy hardeners have been tested in a special epoxy compound patch test series. To analyse the frequency and clinical relevance of allergic reactions to different epoxy hardeners. Test files (January 1991 to March 2013) were screened for contact allergy to different epoxy hardeners, and the clinical records of patients with allergic reactions were analysed for occupation, concomitant allergic reactions, and exposure. The most commonly positive epoxy hardeners were m-xylylenediamine (n = 24), 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP; n = 14), isophorone-diamine (n = 12), and diethylenetriamine (n = 9). Trimethylhexamethylenediamine (n = 7), tetraethylenepentamine (n = 4), and triethylenetetramine (n = 2) elicited some reactions, although most patients were found to have no specific exposure. Allergic reactions to hexamethylenetetramine, dimethylaminopropylamine and ethylenediamine dihydrochloride were not related to epoxy products. Tris-DMP is an important sensitizer in epoxy hardeners, and should be included in the patch test series of epoxy chemicals. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Hydroxyisohexyl 3-cyclohexene carboxaldehyde- known as Lyral: quantitative aspects and risk assessment of an important fragrance allergen.

PubMed

Johansen, J D; Frosch, P J; Svedman, C; Andersen, K E; Bruze, M; Pirker, C; Menné, T

2003-06-01

Hydroxyisohexyl 3-cyclohexene carboxaldehyde, also known as Lyral, is a fragrance ingredient identified as the cause of contact allergic reactions in 2-3% of eczema patients undergoing patch testing. Lyral has been included in the standard patch test series in many clinics due to its importance as an allergen. It has been used without restrictions in cosmetic products, until now. In the present study, the dose-response relationship of Lyral contact allergy was studied with doses relevant for normal exposure in cosmetic products. 18 eczema patients, who previously had given a positive patch test to Lyral 5% petrolatum, were included along with 7 control subjects. All cases were tested with a serial dilution of Lyral in ethanol 6% to 6 p.p.m and subjected to a 2-week, repeated open application test with a low dose of Lyral in ethanol. In the case of no reaction, this was followed by another 2 weeks of testing with a higher dose. The test was performed at the volar aspect of the forearm. In 16 of 18 cases (89%), a positive use test developed, 11 reacting to the low and 5 to the high concentration. None reacted to the vehicle control of ethanol applied to the contralateral arm. All controls were negative to both the test solutions of Lyral and the ethanol control. The difference between the test and the control group was statistically significant (Fisher's test, P < 0.001). It is concluded that Lyral at the current usage levels is inducing sensitization in the community. The same levels were shown to elicit allergic contact dermatitis in almost all sensitized individuals. A significant reduction in usage concentrations is recommended to prevent contact allergic reactions.

Multicenter Patch Testing With Methylisothiazolinone and Methylchloroisothiazolinone/Methylisothiazolinone Within the International Contact Dermatitis Research Group.

PubMed

Isaksson, Marléne; Ale, Iris; Andersen, Klaus E; Elsner, Peter; Goh, Chee-Leok; Goossens, An; Jerajani, Hemangi; Matsunaga, Kayoko; McFadden, John; Bruze, Magnus

The preservatives methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and MI are well-known contact sensitizers. Recently, an increase in the contact allergy frequency for MI 0.2% aqueous (aq) has been seen in many European countries paralleled with an increase in MCI/MI allergy. Many of the MI-allergic patients do not react to MCI/MI 0.01% or 0.02% because the concentration of MI in these preparations is too low (25 and 50 ppm, respectively) to elicit a positive patch test reaction. The aims of this study were to investigate the prevalence of contact allergy to MI in the participating clinics representing various countries all over the world, to assess how many additional individuals with contact allergy are found by testing MI 0.2% aq in parallel with MCI/MI 0.02%, and to assess the clinical relevance of MI and MCI/MI allergies. In 9 dermatology clinics representing 9 countries, 3865 consecutive patients with dermatitis were patch tested with MI 0.2% aq and in parallel with MCI/MI 0.02% aq, provisionally included into the baseline series. An assessment of clinical relevance in those allergic to MI was also made. Contact allergy to MI was found in 284 patients (7.3%). The frequency of contact allergy varied from 0.8% to 10.9% in different centers. Simultaneous reactivity to 200 ppm of MCI/MI was found in 67.3% of the MI-positive patients. Contact allergy to MI alone without any simultaneous contact allergy to 200 ppm of MCI/MI was diagnosed in 93 patients (32.7%; 2.4% of all tested patients). The contact allergy to MI and/or MCI/MI could explain or contribute to dermatitis in more than 60% of the MI-allergic patients. Methylisothiazolinone of 2000 ppm needs to be patch tested on its own to not miss contact allergy.

Sunflower seeds as eliciting agents of Compositae dermatitis.

PubMed

Paulsen, Evy; El-Houri, Rime B; Andersen, Klaus E; Christensen, Lars P

2015-03-01

Sunflowers may cause dermatitis because of allergenic sesquiterpene lactones (SLs). Contact sensitization to sunflower seeds has also been reported, but the allergens are unknown. To analyse sunflower seeds for the presence of SLs and to assess the prevalence of sunflower sensitization in Compositae-allergic individuals. Sunflower-sensitive patients were identified by aimed patch testing. A dichloromethane extract of whole sunflower seeds was analysed by liquid chromatography-mass spectrometry and high-performance liquid chromatography. The prevalence of sensitivity to sunflower in Compositae-allergic individuals was 56%. A solvent wash of whole sunflower seeds yielded an extract containing SLs, the principal component tentatively being identified as argophyllin A or B, other SLs being present in minute amounts. The concentration of SLs on the sunflower seeds is considered high enough to elicit dermatitis in sensitive persons, and it seems appropriate to warn Compositae-allergic subjects against handling sunflower seeds. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Tongue erosions and diet cola.

PubMed

Jacob, Sharon E; Steele, Tace

2007-04-01

We report the case of a 38-year-old woman who presented with a 10-year history of painful ulcerations on her tongue. She reported that she drank large quantities of diet cola and some orange juice daily and that she used cinnamon-flavored toothpaste and mouthwash nightly. Patch testing elicited positive reactions to balsam of Peru (a fragrance as well as a flavoring agent put in cola drinks that cross-reacts with orange juice) and cinnamic aldehyde. She was diagnosed with allergic contact dermatitis. She was put on a restricted diet and a fragrance-free regimen, and her condition resolved.

Asthma, rhinitis, and dermatitis in workers exposed to reactive dyes.

PubMed Central

Nilsson, R; Nordlinder, R; Wass, U; Meding, B; Belin, L

1993-01-01

A survey was conducted at 15 textile plants with dyehouses in western Sweden. Employees with a history of work related rhinitis, asthma, or skin symptoms were offered a clinical and immunological investigation including skin prick tests, skin patch tests, and radioallergosorbent tests (RASTs) to detect specific allergy to reactive dyes. Among the 1142 employees, 162 were exposed to reactive dyes and 10 of these (6%) reported work related respiratory or nasal symptoms. An allergy to reactive dyes could be confirmed in five (3%, 95% confidence interval 1-7%). All but one had been exposed to reactive dyes for one year or less before the onset of symptoms. Positive RASTs could be detected in four of the five patients. All of the RAST positive patients were positive to remazol black B, but six out of eight additional remazol dyes also elicited positive results. RAST and RAST inhibition showed a cross reactivity between some of the dyes. Seven persons with work related dermatitis and three with urticaria or Quincke oedema were found. In one patient contact dermatitis to a monoazo dye was shown, but no positive patch test reactions to reactive dyes. IgE-mediated allergy to reactive dyes seems to be an important cause of respiratory and nasal symptoms among dyehouse employees exposed to dust from reactive dyes. PMID:8431393

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

PubMed

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

2017-05-01

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.

Deodorants: an experimental provocation study with hydroxycitronellal.

PubMed

Svedman, C; Bruze, M; Johansen, J D; Andersen, K E; Goossens, A; Frosch, P J; Lepoittevin, J-P; Rastogi, S; White, I R; Menné, T

2003-04-01

Axillary dermatitis is a common problem, particularly in individuals with contact allergy to fragrances. Many individuals suspect their deodorant to be the causal product of their fragrance allergy. It has been shown that deodorants containing cinnamic aldehyde (cinnamal) can elicit axillary dermatitis in patients sensitized to this substance. The aim of the present investigation was to evaluate the importance of hydroxycitronellal used in deodorants for the development of axillary dermatitis, when applied by individuals with and without contact allergy to this fragrance chemical. Patch tests with deodorants and ethanolic solutions containing hydroxycitronellal, as well as repeated open application tests (ROAT) with roll-on deodorants with and without hydroxycitronellal at different concentrations, were performed in 14 dermatitis patients, 7 with and 7 without contact allergy to hydroxycitronellal. A positive ROAT was noted only in the patients hypersensitive to hydroxycitronellal (P < 0.001) and only in the axilla to which the deodorants containing hydroxycitronellal had been applied (P < 0.001). Deodorants containing hydroxycitronellal in the concentration range of 0.032-0.32% used twice daily on healthy skin in individuals hypersensitive to hydroxycitronellal can elicit axillary dermatitis in a few weeks.

Patch-clamp analysis of voltage-activated and chemically activated currents in the vomeronasal organ of Sternotherus odoratus (stinkpot/musk turtle)

PubMed Central

Fadool, D. A.; Wachowiak, M.; Brann, J. H.

2011-01-01

Summary The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, −54.5±2.7 mV, N=11; input resistance, 6.7±1.4GΩ, N=25; capacitance, 4.2±0.3 pF, N=22; means ± S.E.M.). The voltage-gated K+ current inactivation rate was significantly slower in VN neurons from males than in those from females, and K+ currents in males were less sensitive (greater Ki) to tetraethylammonium. Vomeronasal neurons were held at a holding potential of −60 mV and tested for their response to five natural chemicals, female urine, male urine, female musk, male musk and catfish extract. Of the 90 VN neurons tested, 33 (34 %) responded to at least one of the five compounds. The peak amplitude of chemically evoked currents ranged from 4 to 180 pA, with two-thirds of responses less than 25 pA. Urine-evoked currents were of either polarity, whereas musk and catfish extract always elicited only inward currents. Urine applied to neurons harvested from female animals evoked currents that were 2–3 times larger than those elicited from male neurons. Musk-evoked inward currents were three times the magnitude of urine-or catfish-extract-evoked inward currents. The calculated breadth of responsiveness for neurons presented with this array of five chemicals indicated that the mean response spectrum of the VN neurons is narrow (H metric 0.11). This patch-clamp study indicates that VN neurons exhibit sexual dimorphism in function and specificity in response to complex natural chemicals. PMID:11815645

Patch-clamp analysis of voltage-activated and chemically activated currents in the vomeronasal organ of Sternotherus odoratus (stinkpot/musk turtle).

PubMed

Fadool, D A; Wachowiak, M; Brann, J H

2001-12-01

The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, -54.5 +/- 2.7 mV, N=11; input resistance, 6.7 +/- 1.4 G Omega, N=25; capacitance, 4.2 +/- 0.3 pF, N=22; means +/- S.E.M.). The voltage-gated K(+) current inactivation rate was significantly slower in VN neurons from males than in those from females, and K(+) currents in males were less sensitive (greater K(i)) to tetraethylammonium. Vomeronasal neurons were held at a holding potential of -60 mV and tested for their response to five natural chemicals, female urine, male urine, female musk, male musk and catfish extract. Of the 90 VN neurons tested, 33 (34 %) responded to at least one of the five compounds. The peak amplitude of chemically evoked currents ranged from 4 to 180 pA, with two-thirds of responses less than 25 pA. Urine-evoked currents were of either polarity, whereas musk and catfish extract always elicited only inward currents. Urine applied to neurons harvested from female animals evoked currents that were 2-3 times larger than those elicited from male neurons. Musk-evoked inward currents were three times the magnitude of urine- or catfish-extract-evoked inward currents. The calculated breadth of responsiveness for neurons presented with this array of five chemicals indicated that the mean response spectrum of the VN neurons is narrow (H metric 0.11). This patch-clamp study indicates that VN neurons exhibit sexual dimorphism in function and specificity in response to complex natural chemicals.iol

Cosmetics and herbal remedies with Compositae plant extracts - are they tolerated by Compositae-allergic patients?

PubMed

Paulsen, Evy; Chistensen, Lars P; Andersen, Klaus E

2008-01-01

Compositae-sensitive patients are routinely warned against topical use of Compositae-containing cosmetics and herbal remedies. However, the risk of elicitation of dermatitis in presensitized persons is unknown. The main aim of this study was to assess the significance of direct plant allergen contact via Compositae-derived cosmetics and herbal remedies in Compositae-allergic patients with special reference to arnica (Arnica montana) and German chamomile (Chamomilla recutita). 8 of 12 chamomile-sensitive patients tested positive to chamomile-containing preparations, including tea, creams, ointments, and oil. 5 of 6 arnica-sensitive persons tested positive to arnica-based products. When the group was patch tested with cosmetic and/or herbal product ingredients, plant allergens elicited positive reactions most frequently, but fragrances, emulsifiers, and preservatives tested positive as well. Plant allergens were mainly derived from Compositae, but avocado oil, and Hamamelis virginiana tincture were unexpectedly detected as sensitizers too. Chemical analyses indicated that the Compositae allergens were both sesquiterpene lactones and other naturally occurring compounds. In conclusion, Compositae-allergic persons should be warned against topical use of Compositae-containing products, not only because of the plant allergens, but also because of allergenic cream constituents that may cause reactions in the group of patients who have multiple contact allergies beside the Compositae allergy.

Influence of the vehicle on elicitation of contact allergic reactions to acrylic compounds in the guinea pig.

PubMed

Björkner, B; Niklasson, B

1984-11-01

Many factors can influence the elicitation of hypersensitivity reactions in guinea pigs and humans. The effect which the vehicle might have on the test response in guinea pigs sensitized with various acrylic compounds, using the "guinea pig maximization test", has been investigated. A marked decrease in the number of positive animals was seen when acetone was used as test vehicle, compared to petrolatum. The same result was seen with alcohol as vehicle, when neopentyl glycol diacrylate (NPGDA) was used as an acrylic monomer model. The patch test locations on the guinea pig flank, also affected the test response. Half of the animals did not react when challenged near the abdomen, compared to a test site near the back. By means of HPLC-analysis, the possible adsorption of the acrylic monomer to the aluminium chamber or filter paper disc, was analysed. Our findings did not indicate that adsorption occurs. A decrease in the amount of acrylic monomer in the chamber with increasing time, was noted. There was a marked difference in the monomer residue between solutions with (darkness) and without (daylight) inhibitor. The monomer decrease was also more affected by an aluminium surface than a glass or filter paper surface. Aluminium oxide probably enhances the polymerization process. The discrepancy between the test results in this study, when petrolatum and acetone were used as test vehicles, is due to a polymerization process of the acrylic compounds. Thus, the petrolatum vehicle probably prevents polymerization of the acrylic monomer.

Quantitative aspects of contact allergy to chromium and exposure to chrome-tanned leather.

PubMed

Hansen, Malene Barré; Rydin, Stefan; Menné, Torkil; Duus Johansen, Jeanne

2002-09-01

The potential of trivalent and hexavalent chromium to induce and elicit allergic contact dermatitis and the degree of chromium exposure from leather products are reviewed. Chromium dermatitis is often due to exposure in the occupational environment, with cement being one of the most common chromium sources. However, consumer products such as chromium(III)-tanned leather products are also an important source of chromium exposure. Apart from Cr(III), which is used for tanning, leather often also contains trace amounts of Cr(VI), which is formed by oxidation of Cr(III) during the tanning process. In a recent study of the Cr(VI) content of leather products bought on the Danish market, 35% of such articles had a Cr(VI) content above the detection limit of 3 p.p.m., ranging from 3.6 p.p.m. to 14.7 p.p.m. Leachable Cr(III) was detected at levels of 430-980 p.p.m. An examination of available dose-response studies showed that exposure to occluded patch test concentrations of 7-45 p.p.m. Cr(VI) elicits a reaction in 10% of the chromium-sensitive patients. When reviewing repeated open exposure studies, it is seen that either exposure to 5 p.p.m. Cr(VI) in the presence of 1% sodium lauryl sulfate (SLS) or exposure to 10 p.p.m. Cr(VI) alone both elicit eczema in chromium-sensitive patients. The eliciting capacity of Cr(III) has not been systematically investigated but, compared to Cr(VI), much higher concentrations are needed to elicit eczema.

Nevirapine patch testing in Thai human immunodeficiency virus infected patients with nevirapine drug hypersensitivity.

PubMed

Prasertvit, Piyatida; Chareonyingwattana, Angkana; Wattanakrai, Penpun

2017-12-01

Antiretroviral drug hypersensitivity in HIV patients is common. Publications have shown that Abacavir (ABC) patch testing is useful in confirming ABC hypersensitivity in 24-50% of cases with a 100% sensitivity of HLA-B*5701 in patch test positive cases. However, Nevirapine (NVP) patch testing has not been reported. (1) To evaluate the usefulness and safety of NVP patch testing in Thai HIV patients with NVP hypersensitivity. (2) To assess the correlation of positive patch tests with HLA-B*3505. Patients were classified into two groups: (1) study group of 20 HIV NVP hypersensitivity patients and (2) control group of 15 volunteers without NVP hypersensitivity. Both groups were patch tested with purified and commercialized form of NVP in various vehicles. Two HIV patients with NVP hypersensitivity were patch test positive. All controls tested negative. Three HIV patients were positive for HLA-B*3505 and the two patients with positive patch testing were both HLA-B*3505 positive. NVP patch testing in Thai HIV patients is safe and can be used to help confirm the association between NVP and hypersensitivity skin reactions. NVP patch test results significantly correlated with HLA-B*3505. The sensitivity of HLA-B*3505 for positive patch test was 100%. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Patch testing in children from 2005 to 2012: results from the North American contact dermatitis group.

PubMed

Zug, Kathryn A; Pham, Anh Khoa; Belsito, Donald V; DeKoven, Joel G; DeLeo, Vincent A; Fowler, Joseph F; Fransway, Anthony F; Maibach, Howard I; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Sasseville, Denis; Storrs, Frances J; Taylor, James S; Warshaw, Erin M; Zirwas, Matthew J

2014-01-01

Allergic contact dermatitis is common in children. Epicutaneous patch testing is an important tool for identifying responsible allergens. The objective of this study was to provide the patch test results from children (aged ≤18 years) examined by the North American Contact Dermatitis Group from 2005 to 2012. This is a retrospective analysis of children patch-tested with the North American Contact Dermatitis Group 65- or 70-allergen series. Frequencies and counts were compared with previously published data (2001-2004) using χ statistics. A total of 883 children were tested during the study period. A percentage of 62.3% had ≥1 positive patch test and 56.7% had ≥1 relevant positive patch test. Frequencies of positive patch test and relevant positive patch test reaction were highest with nickel sulfate (28.1/25.6), cobalt chloride (12.3/9.1), neomycin sulfate (7.1/6.6), balsam of Peru (5.7/5.5), and lanolin alcohol 50% petrolatum vehicle (5.5/5.1). The ≥1 positive patch test and ≥1 relevant positive patch test in the children did not differ significantly from adults (≥19 years) or from previously tested children (2001-2004). The percentage of clinically relevant positive patch tests for 27 allergens differed significantly between the children and adults. A total of 23.6% of children had a relevant positive reaction to at least 1 supplemental allergen. Differences in positive patch test and relevant positive patch test frequencies between children and adults as well as test periods confirm the importance of reporting periodic updates of patch testing in children to enhance clinicians' vigilance to clinically important allergens.

Comparing reliabilities of strip and conventional patch testing.

PubMed

Dickel, Heinrich; Geier, Johannes; Kreft, Burkhard; Pfützner, Wolfgang; Kuss, Oliver

2017-06-01

The standardized protocol for performing the strip patch test has proven to be valid, but evidence on its reliability is still missing. To estimate the parallel-test reliability of the strip patch test as compared with the conventional patch test. In this multicentre, prospective, randomized, investigator-blinded reliability study, 132 subjects were enrolled. Simultaneous duplicate strip and conventional patch tests were performed with the Finn Chambers ® on Scanpor ® tape test system and the patch test preparations nickel sulfate 5% pet., potassium dichromate 0.5% pet., and lanolin alcohol 30% pet. Reliability was estimated by the use of Cohen's kappa coefficient. Parallel-test reliability values of the three standard patch test preparations turned out to be acceptable, with slight advantages for the strip patch test. The differences in reliability were 9% (95%CI: -8% to 26%) for nickel sulfate and 23% (95%CI: -16% to 63%) for potassium dichromate, both favouring the strip patch test. The standardized strip patch test method for the detection of allergic contact sensitization in patients with suspected allergic contact dermatitis is reliable. Its application in routine clinical practice can be recommended, especially if the conventional patch test result is presumably false negative. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bacteroides induce higher IgA production than Lactobacillus by increasing activation-induced cytidine deaminase expression in B cells in murine Peyer's patches.

PubMed

Yanagibashi, Tsutomu; Hosono, Akira; Oyama, Akihito; Tsuda, Masato; Hachimura, Satoshi; Takahashi, Yoshimasa; Itoh, Kikuji; Hirayama, Kazuhiro; Takahashi, Kyoko; Kaminogawa, Shuichi

2009-02-01

The gut mucosal immune system is crucial in host defense against infection by pathogenic microbacteria and viruses via the production of IgA. Previous studies have shown that intestinal commensal bacteria enhance mucosal IgA production. However, it is poorly understood how these bacteria induce IgA production and which genera of intestinal commensal bacteria induce IgA production effectively. In this study, we compared the immunomodulatory effects of Bacteroides and Lactobacillus on IgA production by Peyer's patches lymphocytes. IgA production by Peyer's patches lymphocytes co-cultured with Bacteroides was higher than with Lactobacillus. In addition, the expression of activation-induced cytidine deaminase increased in co-culture with Bacteroides but not with Lactobacillus. We found that intestinal commensal bacteria elicited IgA production. In particular, Bacteroides induced the differentiation of Peyer's patches B cell into IgA(+) B cells by increasing activation-induced cytidine deaminase expression.

Direct demonstration of persistent Na+ channel activity in dendritic processes of mammalian cortical neurones

PubMed Central

Magistretti, Jacopo; Ragsdale, David S; Alonso, Angel

1999-01-01

Single Na+ channel activity was recorded in patch-clamp, cell-attached experiments performed on dendritic processes of acutely isolated principal neurones from rat entorhinal-cortex layer II. The distances of the recording sites from the soma ranged from ≈20 to ≈100 μm.Step depolarisations from holding potentials of −120 to −100 mV to test potentials of −60 to +10 mV elicited Na+ channel openings in all of the recorded patches (n= 16).In 10 patches, besides transient Na+ channel openings clustered within the first few milliseconds of the depolarising pulses, prolonged and/or late Na+ channel openings were also regularly observed. This ‘persistent’ Na+ channel activity produced net inward, persistent currents in ensemble-average traces, and remained stable over the entire duration of the experiments (≈9 to 30 min).Two of these patches contained <= 3 channels. In these cases, persistent Na+ channel openings could be attributed to the activity of one single channel.The voltage dependence of persistent-current amplitude in ensemble-average traces closely resembled that of whole-cell, persistent Na+ current expressed by the same neurones, and displayed the same characteristic low threshold of activation.Dendritic, persistent Na+ channel openings had relatively high single-channel conductance (≈20 pS), similar to what is observed for somatic, persistent Na+ channels.We conclude that a stable, persistent Na+ channel activity is expressed by proximal dendrites of entorhinal-cortex layer II principal neurones, and can contribute a significant low-threshold, persistent Na+ current to the dendritic processing of excitatory synaptic inputs. PMID:10601494

Facilitation of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor transmission in the suprachiasmatic nucleus by aniracetam enhances photic responses of the biological clock in rodents.

PubMed

Moriya, Takahiro; Ikeda, Masayuki; Teshima, Koji; Hara, Reiko; Kuriyama, Koji; Yoshioka, Tohru; Allen, Charles N; Shibata, Shigenobu

2003-05-01

This study was designed to test whether the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor-facilitating drug, aniracetam, could potentiate photic responses of the biological clock in the suprachiasmatic nucleus (SCN) of rodents. Using the whole-cell patch technique, we first demonstrated that AMPA currents elicited by either local AMPA application or optic chiasm stimulation were augmented by aniracetam in the neurons of the SCN. The AMPA application-elicited increase of intracellular Ca2+ concentration in SCN slices was also enhanced by aniracetam treatment. The systemic injection of aniracetam dose-dependently (10-100 mg/kg) potentiated the phase delay in behavioral rhythm induced by brief light exposure of low intensity (3 lux) but not high intensity (10 or 60 lux) during early subjective night. Under the blockade of NMDA receptors by (+) MK801, aniracetam failed to potentiate a light (3 lux)-induced phase delay in behavioral rhythm. Aniracetam increased the photic induction of c-Fos protein in the SCN that was elicited by low intensity light exposure (3 lux). These results suggest that AMPA receptor-mediated responses facilitated by aniracetam can explain enhanced photic responses of the biological clock in the SCN of rodents.

Cosmetic Contact Sensitivity in Patients with Melasma: Results of a Pilot Study

PubMed Central

Prabha, Neel; Mahajan, Vikram K.; Mehta, Karaninder S.; Chauhan, Pushpinder S.

2014-01-01

Background. Some of the patients with melasma perhaps have pigmented cosmetic dermatitis. However, cosmetic contact sensitivity in melasma remains poorly studied particularly in the Indian context. Objectives. To study cosmetic contact sensitivity in patients with melasma. Materials and Methods. 67 (F : M = 55 : 12) consecutive patients with melasma between 19 and 49 years of age were patch tested sequentially during January–December, 2012, with Indian Cosmetic and Fragrance Series, Indian Sunscreen Series, p-phenylenediamine, and patient's own cosmetic products. Results. 52 (78%) patients were in the age group of 20–40 years. The duration of melasma varied from 1 month to 20 years. Centrofacial, malar, and mandibular patterns were observed in 48 (72%), 18 (27%), and 1 (1%) patients, respectively. Indian Cosmetics and Fragrance Series elicited positive reactions in 29 (43.3%) patients. Cetrimide was the most common contact sensitizers eliciting positivity in 15 (52%) patients, followed by gallate mix in 9 (31%) patients and thiomersal in 7 (24%) patients. Only 2 of the 42 patients showed positive reaction from their own cosmetics while the other 5 patients had irritant reaction. Indian Sunscreen Series did not elicit any positive reaction. Conclusion. Cosmetics contact sensitivity appears as an important cause of melasma not associated with pregnancy, lactation, or hormone therapy. PMID:25132846

Allergic contact dermatitis to acrylates in disposable blue diathermy pads.

PubMed Central

Sidhu, S. K.; Shaw, S.

1999-01-01

We report 2 cases of elicitation of allergic contact dermatitis to acrylates from disposable blue diathermy pads used on patients who underwent routine surgery. Their reactions were severe, and took approximately 5 weeks to resolve. Both patients gave a prior history of finger tip dermatitis following the use of artificial sculptured acrylic nails, which is a common, but poorly reported, cause of acrylate allergy. Patch testing subsequently confirmed allergies to multiple acrylates present in both the conducting gel of disposable blue diathermy pads, and artificial sculptured acrylic nails. We advocate careful history taking prior to surgery to avoid unnecessary exposure to acrylates in patients already sensitized. Images Figure 1 Figure 2 PMID:10364952

A localized flare of dermatitis may render patch tests uninterpretable in some patients with recently controlled widespread dermatitis.

PubMed

Magembe, Anna J; Davis, Mark D P; Richardson, Donna M

2009-01-01

Patch testing rarely is confounded by localized dermatitis induced in the area being tested (usually the back). Its occurrence renders the interpretation of patch tests impossible. To review our experience of the circumstances in which this phenomenon occurs during patch testing. We retrospectively reviewed patients with this phenomenon who underwent patch testing from January 1, 2002, through June 30, 2006. Of the 3,569 patients tested, 12 (0.34% [9 men and 3 women]) had development of this phenomenon. All patients previously had recent widespread dermatitis that was suppressed temporarily with topical corticosteroids and wet dressings at the time of patch testing. The period between control of the dermatitis and the initiation of patch testing was less than 1 week for all patients. Three patients (25%) had recently discontinued therapy with systemic corticosteroids (less than 1 week earlier). In patients with irritable skin either immediately after widespread dermatitis is controlled or after the cessation of systemic corticosteroid treatment, a flare of dermatitis induced by patch testing may render patch tests unreadable and therefore uninterpretable. To avoid this confounding occurrence, a waiting period between control of widespread dermatitis and initiation of patch testing is advised.

Audio-visual synchrony and feature-selective attention co-amplify early visual processing.

PubMed

Keitel, Christian; Müller, Matthias M

2016-05-01

Our brain relies on neural mechanisms of selective attention and converging sensory processing to efficiently cope with rich and unceasing multisensory inputs. One prominent assumption holds that audio-visual synchrony can act as a strong attractor for spatial attention. Here, we tested for a similar effect of audio-visual synchrony on feature-selective attention. We presented two superimposed Gabor patches that differed in colour and orientation. On each trial, participants were cued to selectively attend to one of the two patches. Over time, spatial frequencies of both patches varied sinusoidally at distinct rates (3.14 and 3.63 Hz), giving rise to pulse-like percepts. A simultaneously presented pure tone carried a frequency modulation at the pulse rate of one of the two visual stimuli to introduce audio-visual synchrony. Pulsed stimulation elicited distinct time-locked oscillatory electrophysiological brain responses. These steady-state responses were quantified in the spectral domain to examine individual stimulus processing under conditions of synchronous versus asynchronous tone presentation and when respective stimuli were attended versus unattended. We found that both, attending to the colour of a stimulus and its synchrony with the tone, enhanced its processing. Moreover, both gain effects combined linearly for attended in-sync stimuli. Our results suggest that audio-visual synchrony can attract attention to specific stimulus features when stimuli overlap in space.

An observational study on the effects of aviation turbine fuel and lubricants on the skin of Indian Air Force ground crew in flying stations.

PubMed

Radhakrishnan, S; Chopra, Ajay; Mitra, Debdeep; Gnanasekaran, R; Kanagaraj, R

2017-07-01

Ground crew of the Air Force routinely handle aviation turbine fuel (ATF) and lubricants and a need was felt to study the adverse effects of these substances on their skin so that remedial measures could be taken to prevent these adverse effects. A multi-centric, cross-sectional, observational study was performed at three Air Force flying stations. 109 ground crew members of the Indian Air Force (IAF) who were in direct contact with ATF and lubricants were screened for dermatological manifestations on exposed areas. History of atopy was elicited, systemic and dermatological examination done and occlusive patch testing carried out where indicated. Fungal infections were excluded by a potassium hydroxide mount. 20 out of the 109 personnel (18.34%) were symptomatic in the form of mild irritant contact dermatitis. There was no case of allergic contact dermatitis. Only two cases showed an irritant reaction on patch testing. 65% of the symptomatic personnel were atopic. There was no predisposing trade or age group for adverse effects to ATF. This study revealed that contact with ATF is associated with only mild irritant contact dermatitis in exposed ground crew members of the IAF and atopy was a predisposing factor for susceptibility to the dermatitis.

A Comparison of Patched HOTV Visual Acuity and Photoscreening

ERIC Educational Resources Information Center

Leman, Rachel; Clausen, Michelle M.; Bates, Janice; Stark, Lee; Arnold, Koni K.; Arnold, Robert W.

2006-01-01

Early detection of significant vision problems in children is a high priority for pediatricians and school nurses. Routine vision screening is a necessary part of that detection and has traditionally involved acuity charts. However, photoscreening in which "red eye" is elicited to show whether each eye is focusing may outperform routine acuity…

Skin test performed with highly purified Mycobacterium tuberculosis recombinant protein triggers tuberculin shock in infected guinea pigs.

PubMed

Reece, Stephen T; Stride, Nicole; Ovendale, Pamela; Reed, Steven G; Campos-Neto, Antonio

2005-06-01

Tuberculin shock due to inoculation of Mycobacterium tuberculosis antigens in patients with tuberculosis is a serious syndrome originally described over 100 years ago by Robert Koch. Here, we present experimental evidence that a single M. tuberculosis recombinant protein, CFP-10, triggers this syndrome. Intradermal inoculation of CFP-10 elicits in M. tuberculosis-infected mice high levels of serum tumor necrosis factor alpha and causes tuberculin shock in infected guinea pigs characterized by hypothermia and death within 6 to 48 h after the antigen inoculation. Autopsies of these animals revealed intense polycythemia and hemorrhagic patches in the lung parenchyma, a pathological observation consistent with tuberculin shock. These results point to the possible occurrence of tuberculin shock in sensitive individuals inoculated with highly purified M. tuberculosis recombinant proteins as vaccine candidates or skin test reagents.

Patch Test Negative Generalized Dermatitis.

PubMed

Spiker, Alison; Mowad, Christen

2016-01-01

Allergic contact dermatitis is a common condition in dermatology. Patch testing is the criterion standard for diagnosis. However, dermatitis is not always caused by an allergen, and patch testing does not identify a culprit in every patient. Generalized dermatitis, defined as eczematous dermatitis affecting greater than 3 body sites, is often encountered in dermatology practice, especially patch test referral centers. Management for patients with generalized dermatitis who are patch test negative is challenging. The purpose of this article is to outline an approach to this challenging scenario and summarize the paucity of existing literature on patch test negative generalized dermatitis.

Evaluation of canine adverse food reactions by patch testing with single proteins, single carbohydrates and commercial foods.

PubMed

Johansen, Cornelia; Mariani, Claire; Mueller, Ralf S

2017-10-01

Adverse food reaction (AFR) is an important differential diagnosis for the pruritic dog. It is usually diagnosed by feeding an elimination diet with a novel protein and carbohydrate source for eight weeks followed by subsequent food provocation. A previous study demonstrated that patch testing dogs with foods had a high sensitivity and negative predictability for selection of elimination diet ingredients. The aim of this study was to investigate patch testing with proteins, carbohydrates and dry commercial dog food in dogs to determine whether there was value in patch testing to aid the diagnosis of canine adverse food reaction. Twenty five privately owned dogs, with confirmed AFR, underwent provocation trials with selected food antigens and patch testing. For proteins, carbohydrates and dry dog food the sensitivity of patch testing was 100%, 70% and 22.2%, respectively; the negative predictive values of patch testing were 100%, 79% and 72%. The positive predictive values of patch testing for proteins and carbohydrates were 75% and 74%, respectively. This study confirmed that patch testing may be useful for the selection of a suitable protein source for an elimination diet in dogs with suspected AFR, but not as a diagnostic tool for canine AFR. Results for proteins are more reliable than for carbohydrates and the majority of positive patch test reactions were observed with raw protein. Patch testing with commercial dog food does not seem to be useful. © 2017 ESVD and ACVD.

Clash of kingdoms or why Drosophila larvae positively respond to fungal competitors.

PubMed

Rohlfs, Marko

2005-01-27

BACKGROUND: Competition with filamentous fungi has been demonstrated to be an important cause of mortality for the vast group of insects that depend on ephemeral resources (e.g. fruit, dung, carrion). Recent data suggest that the well-known aggregation of Drosophila larvae across decaying fruit yields a competitive advantage over mould, by which the larvae achieve a higher survival probability in larger groups compared with smaller ones. Feeding and locomotor behaviour of larger larval groups is assumed to cause disruption of fungal hyphae, leading to suppression of fungal growth, which in turn improves the chances of larval survival to the adult stage. Given the relationship between larval density, mould suppression and larval survival, the present study has tested whether fungal-infected food patches elicit communal foraging behaviour on mould-infected sites by which larvae might hamper mould growth more efficiently. RESULTS: Based on laboratory experiments in which Drosophila larvae were offered the choice between fungal-infected and uninfected food patches, larvae significantly aggregated on patches containing young fungal colonies. Grouping behaviour was also visible when larvae were offered only fungal-infected or only uninfected patches; however, larval aggregation was less strong under these conditions than in a heterogeneous environment (infected and uninfected patches). CONCLUSION: Because filamentous fungi can be deadly competitors for insect larvae on ephemeral resources, social attraction of Drosophila larvae to fungal-infected sites leading to suppression of mould growth may reflect an adaptive behavioural response that increases insect larval fitness and can thus be discussed as an anti-competitor behaviour. These observations support the hypothesis that adverse environmental conditions operate in favour of social behaviour. In a search for the underlying mechanisms of communal behaviour in Drosophila, this study highlights the necessity of investigating the role of inter-kingdom competition as a potential driving force in the evolution of spatial behaviour in insects.

Stratum corneum profiles of inflammatory mediators in patch test reactions to common contact allergens and sodium lauryl sulfate.

PubMed

Koppes, S A; Ljubojevic Hadzavdic, S; Jakasa, I; Franceschi, N; Jurakić Tončić, R; Marinović, B; Brans, R; Gibbs, S; Frings-Dresen, M H W; Rustemeyer, T; Kezic, S

2017-06-01

Recent studies have demonstrated allergen-specific differences in the gene expression of inflammatory mediators in patch tested skin. To determine levels of various inflammatory mediators in the stratum corneum (SC) after patch testing with common contact allergens and the skin irritant sodium lauryl sulfate (SLS). In total, 27 individuals who had previously patch tested positive to nickel, chromium, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) or para-phenylenediamine were retested and then patch tested with SLS and petrolatum, with petrolatum serving as the patch test control. At 72 h, the test sites were clinically graded and the SC samples collected on adhesive tape. The levels of 18 of the 32 quantified mediators differed significantly from that of the control patches for at least one of the tested substances. SLS and MCI/MI induced the largest number of immunomediators. Interleukin (IL)-16 levels were significantly higher in patch test reactions in all allergens than they were in the controls, while no significant difference was detected for SLS. Furthermore, a strong negative correlation was found between strength of patch test reaction and IL-1α levels. Cytokine profiles in the SC of patch tested skin did not show a distinct allergen-specific pattern. However, MCI/MI induced a larger and wider immune response than the other allergens, perhaps due to its potency as an irritant. The levels of IL-16 were significantly increased in patch test reactions to allergens but not to SLS; thus, they may help clinicians to differentiate between allergic contact dermatitis and irritant contact dermatitis. © 2016 British Association of Dermatologists.

Early Antibody Lineage Diversification and Independent Limb Maturation Lead to Broad HIV-1 Neutralization Targeting the Env High-Mannose Patch.

PubMed

MacLeod, Daniel T; Choi, Nancy M; Briney, Bryan; Garces, Fernando; Ver, Lorena S; Landais, Elise; Murrell, Ben; Wrin, Terri; Kilembe, William; Liang, Chi-Hui; Ramos, Alejandra; Bian, Chaoran B; Wickramasinghe, Lalinda; Kong, Leopold; Eren, Kemal; Wu, Chung-Yi; Wong, Chi-Huey; Kosakovsky Pond, Sergei L; Wilson, Ian A; Burton, Dennis R; Poignard, Pascal

2016-05-17

The high-mannose patch on HIV Env is a preferred target for broadly neutralizing antibodies (bnAbs), but to date, no vaccination regimen has elicited bnAbs against this region. Here, we present the development of a bnAb lineage targeting the high-mannose patch in an HIV-1 subtype-C-infected donor from sub-Saharan Africa. The Abs first acquired autologous neutralization, then gradually matured to achieve breadth. One Ab neutralized >47% of HIV-1 strains with only ∼11% somatic hypermutation and no insertions or deletions. By sequencing autologous env, we determined key residues that triggered the lineage and participated in Ab-Env coevolution. Next-generation sequencing of the Ab repertoire showed an early expansive diversification of the lineage followed by independent maturation of individual limbs, several of them developing notable breadth and potency. Overall, the findings are encouraging from a vaccine standpoint and suggest immunization strategies mimicking the evolution of the entire high-mannose patch and promoting maturation of multiple diverse Ab pathways. Copyright © 2016 Elsevier Inc. All rights reserved.

A Pragmatic Approach to Patch Testing Atopic Dermatitis Patients: Clinical Recommendations Based on Expert Consensus Opinion.

PubMed

Chen, Jennifer K; Jacob, Sharon E; Nedorost, Susan T; Hanifin, Jon M; Simpson, Eric L; Boguniewicz, Mark; Watsky, Kalman L; Lugo-Somolinos, Aida; Hamann, Carsten R; Eberting, Cheryl Lee; Silverberg, Jonathan I; Thyssen, Jacob P

2016-01-01

Allergic contact dermatitis (ACD) may complicate the clinical course of atopic dermatitis (AD), and patch testing remains the criterion standard for diagnosing ACD. To date, there have been no guidelines or consensus recommendations on when and how to patch test individuals with AD. Failure to patch test when appropriate may result in overlooking an important and potentially curable complicating comorbidity. In this article, we present consensus recommendations regarding when to perform patch testing in the AD patient, best practices, and common pitfalls. Patch testing should be considered in AD patients with dermatitis that fails to improve with topical therapy; with atypical/changing distribution of dermatitis, or pattern suggestive of ACD; with therapy-resistant hand eczema in the working population; with adult- or adolescent-onset AD; and/or before initiating systemic immunosuppressants for the treatment of dermatitis. A suggested patch testing algorithm for AD patients is provided.

Results of patch testing in 10 patients with peristomal dermatitis.

PubMed

Landis, Megan N; Keeling, James H; Yiannias, James A; Richardson, Donna M; Nordberg Linehan, Diane L; Davis, Mark D P

2012-09-01

Peristomal dermatitis is a common problem in patients with ostomies that is a source of considerable morbidity. Irritant contact dermatitis is most common, but allergic contact dermatitis can also occur. Because of the lack of published reports on patch testing for this indication, we undertook a retrospective study of patch testing results in patients with suspected peristomal allergic contact dermatitis. We sought to describe our patch testing experience with patients referred with peristomal dermatitis. This was a retrospective review of medical records of patients with ostomies and peristomal dermatitis who underwent patch testing in the Mayo Clinic Departments of Dermatology in Jacksonville, FL; Rochester, MN; and Scottsdale, AZ, during a 10-year period (2000-2010). Ten patients with peristomal dermatitis were referred for patch testing (6 in Minnesota, 2 in Florida, and 2 in Arizona). Patients were patch tested to the materials used in their stoma devices, to the standard series, and in some cases to supplemental series. All 10 had at least one allergic patch test reaction, most commonly to stoma paste (3 of 10 patients). Retrospective nature of study via chart review is a limitation. Patch testing is a useful tool for identification of allergens in patients with peristomal dermatitis. Copyright © 2011 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Thiol-ene mediated neoglycosylation of collagen patches: a preliminary study.

PubMed

Russo, Laura; Battocchio, Chiara; Secchi, Valeria; Magnano, Elena; Nappini, Silvia; Taraballi, Francesca; Gabrielli, Luca; Comelli, Francesca; Papagni, Antonio; Costa, Barbara; Polzonetti, Giovanni; Nicotra, Francesco; Natalello, Antonino; Doglia, Silvia M; Cipolla, Laura

2014-02-11

Despite the relevance of carbohydrates as cues in eliciting specific biological responses, the covalent surface modification of collagen-based matrices with small carbohydrate epitopes has been scarcely investigated. We report thereby the development of an efficient procedure for the chemoselective neoglycosylation of collagen matrices (patches) via a thiol-ene approach, between alkene-derived monosaccharides and the thiol-functionalized material surface. Synchrotron radiation-induced X-ray photoelectron spectroscopy (SR-XPS), Fourier transform-infrared (FT-IR), and enzyme-linked lectin assay (ELLA) confirmed the effectiveness of the collagen neoglycosylation. Preliminary biological evaluation in osteoarthritic models is reported. The proposed methodology can be extended to any thiolated surface for the development of smart biomaterials for innovative approaches in regenerative medicine.

Deodorants: an experimental provocation study with isoeugenol.

PubMed

Bruze, Magnus; Johansen, Jeanne D; Andersen, Klaus Ejner; Frosch, Peter; Goossens, An; Lepoittevin, Jean-Pierre; Rastogi, Suresh C; White, Ian; Menné, Torkil

2005-05-01

Axillary dermatitis is common and overrepresented in people with contact allergy to fragrances. Many people suspect their deodorants to be the incriminating products. In order to investigate the significance of isoeugenol in deodorants for the development of axillary dermatitis when used by people with and without contact allergy to isoeugenol, patch tests with deodorants and ethanol solutions with isoeugenol, as well as repeated open application tests (ROAT) with roll-on deodorants with and without isoeugenol at various concentrations, were performed in 35 dermatitis patients, 10 without and 25 with contact allergy to isoeugenol. A positive ROAT was observed only in patients hypersensitive to isoeugenol (P<0.001) and only in the axilla to which the deodorants containing isoeugenol had been applied (P<0.001). Deodorants containing isoeugenol in the concentration range of 0.0063-0.2% used 2 times daily on healthy skin can thus elicit axillary dermatitis within a few weeks in people with contact allergy to isoeugenol.

Atopy patch test reactions to house dust mites in patients with scabies.

PubMed

Taşkapan, Oktay; Harmanyeri, Yavuz

2005-01-01

It is well known that the house dust and the scabies mites are related phylogenetically. We therefore performed atopy patch tests with house dust mite antigens (Dermatophagoides pteronyssinus (Dp) and/or Dermatophagoides farinae (Df)) in scabies patients without atopy and healthy controls. We studied 25 men with active scabies and 25 healthy controls. Skin prick tests with standardized house dust mite extract were performed for all patients and controls. An intradermal test procedure was carried out in skin prick test-negative patients, and for controls showing positive atopy patch test to Dp and/or Df. While atopy patch tests were performed directly in all healthy controls, patients with scabies were first treated and on the next day, atopy patch tests were performed. Twenty-two of 25 patients with scabies (88%) had skin prick test and/or intradermal test positivity against house dust mites, whereas 17/25 patients (68%) had atopy patch test positivity against house dust mites (Dp and/or Df). There was no statistically significant difference between skin prick test and/or intradermal test positivity and atopy patch test positivity in a regression analysis (p=0.222). The only statistically significant correlation was between atopy patch test positivity and the extent of scabies involvement (p<0.05). Only few of the healthy controls had positive tests. In this study, we have shown that a positive atopy patch test to house dust mite antigens is not specific for patients with atopic dermatitis, but also occurs in scabies patients without a history of atopic dermatitis.

Is there a risk of active sensitization to PPD by patch testing the general population?

PubMed

Thyssen, Jacob Pontoppidan; Menné, Torkil; Nielsen, Niels Henrik; Linneberg, Allan

2007-08-01

Para-phenylenediamine (PPD), a constituent of permanent hair dyes, may cause contact allergy in exposed individuals. It has previously been questioned whether a patch testing with PPD in population-based epidemiological studies is entirely safe. The Glostrup allergy studies patch tested the same cohort twice. In 1990, 567 persons were patch-tested and only one person had a (+) positive reaction to PPD. In 1998, 540 persons were re-invited to a new patch test and 365 (participation rate 68%) were re-tested. There were no positive reactions to PPD. These studies indicate that patch testing with PPD in individuals with no previous positive reactions to PPD or with only one previous positive reaction does not cause active sensitization and can be performed with minimal risk.

Selective versus routine patch metal allergy testing to select bar material for the Nuss procedure in 932 patients over 10years.

PubMed

Obermeyer, Robert J; Gaffar, Sheema; Kelly, Robert E; Kuhn, M Ann; Frantz, Frazier W; McGuire, Margaret M; Paulson, James F; Kelly, Cynthia S

2018-02-01

The aim of the study was to determine the role of patch metal allergy testing to select bar material for the Nuss procedure. An IRB-approved (11-04-WC-0098) single institution retrospective, cohort study comparing selective versus routine patch metal allergy testing to select stainless steel or titanium bars for Nuss repair was performed. In Cohort A (9/2004-1/2011), selective patch testing was performed based on clinical risk factors. In Cohort B (2/2011-9/2014), all patients were patch tested. The cohorts were compared for incidence of bar allergy and resultant premature bar loss. Risk factors for stainless steel allergy or positive patch test were evaluated. Cohort A had 628 patients with 63 (10.0%) selected for patch testing, while all 304 patients in Cohort B were tested. Over 10years, 15 (1.8%) of the 842 stainless steel Nuss repairs resulted in a bar allergy, and 5 had a negative preoperative patch test. The incidence of stainless steel bar allergy (1.8% vs 1.7%, p=0.57) and resultant bar loss (0.5% vs 1.3%, p=0.23) was not statistically different between cohorts. An allergic reaction to a stainless steel bar or a positive patch test was more common in females (OR=2.3, p<0.001) and patients with a personal (OR=24.8, p<0.001) or family history (OR=3.1, p<0.001) of metal sensitivity. Stainless steel bar allergies occur at a low incidence with either routine or selective patch metal allergy testing. If selective testing is performed, it is advisable in females and patients with a personal or family history of metal sensitivity. A negative preoperative patch metal allergy test does not preclude the possibility of a postoperative stainless steel bar allergy. Level III Treatment Study and Study of Diagnostic Test. Copyright © 2017 Elsevier Inc. All rights reserved.

Deodorants: an experimental provocation study with cinnamic aldehyde.

PubMed

Bruze, Magnus; Johansen, J D; Andersen, K E; Frosch, P; Lepoittevin, J-P; Rastogi, S; Wakelin, S; White, I; Menné, T

2003-02-01

Axillary dermatitis is common and overrepresented in individuals with contact allergy to fragrances. Many individuals suspect their deodorants to be the incriminating products. Our aim was to investigate the significance of cinnamic aldehyde in deodorants for the development of axillary dermatitis when used by individuals with and without contact allergy to cinnamic aldehyde. Patch tests with deodorants and ethanol solutions with cinnamic aldehyde, and repeated open application tests with roll-on deodorants without and with cinnamic aldehyde at different concentrations, were performed in 37 patients with dermatitis, 20 without and 17 with contact allergy to cinnamic aldehyde. A repeated open application test with positive findings was noted only in patients hypersensitive to cinnamic aldehyde (P <.001) and only in the axilla to which the deodorants containing cinnamic aldehyde had been applied (P <.001). Deodorants containing cinnamic aldehyde in the concentration range 0.01% to 0.32%, used twice daily on healthy skin, can elicit axillary dermatitis within a few weeks.

Single-unit activity during natural vision: diversity, consistency, and spatial sensitivity among AF face patch neurons.

PubMed

McMahon, David B T; Russ, Brian E; Elnaiem, Heba D; Kurnikova, Anastasia I; Leopold, David A

2015-04-08

Several visual areas within the STS of the macaque brain respond strongly to faces and other biological stimuli. Determining the principles that govern neural responses in this region has proven challenging, due in part to the inherently complex stimulus domain of dynamic biological stimuli that are not captured by an easily parameterized stimulus set. Here we investigated neural responses in one fMRI-defined face patch in the anterior fundus (AF) of the STS while macaques freely view complex videos rich with natural social content. Longitudinal single-unit recordings allowed for the accumulation of each neuron's responses to repeated video presentations across sessions. We found that individual neurons, while diverse in their response patterns, were consistently and deterministically driven by the video content. We used principal component analysis to compute a family of eigenneurons, which summarized 24% of the shared population activity in the first two components. We found that the most prominent component of AF activity reflected an interaction between visible body region and scene layout. Close-up shots of faces elicited the strongest neural responses, whereas far away shots of faces or close-up shots of hindquarters elicited weak or inhibitory responses. Sensitivity to the apparent proximity of faces was also observed in gamma band local field potential. This category-selective sensitivity to spatial scale, together with the known exchange of anatomical projections of this area with regions involved in visuospatial analysis, suggests that the AF face patch may be specialized in aspects of face perception that pertain to the layout of a social scene.

Trichloroethylene Hypersensitivity Syndrome Is Potentially Mediated through Its Metabolite Chloral Hydrate.

PubMed

Huang, Yongshun; Xia, Lihua; Wu, Qifeng; Zeng, Zifang; Huang, Zhenlie; Zhou, Shanyu; Jin, Jiachun; Huang, Hanlin

2015-01-01

We documented previously the entity of trichloroethylene (TCE) hypersensitivity syndrome (THS) in occupational workers. To identify the culprit causative compound, determine the type of hypersensitivity of THS, and establish a screening test for subjects at risk of THS. TCE and its main metabolites chloral hydrate (CH), trichloroethanol (TCOH) and trichloroacetic acid (TCA) were used as allergens at different concentrations in skin patch tests. The study included 19 case subjects diagnosed with occupational THS, 22 control healthy workers exposed to TCE (exposure >12 weeks), and 20 validation new workers exposed to TCE for <12 weeks free of THS. All subjects were followed-up for 12 weeks after the patch test. The highest patch test positive rate in subjects with THS was for CH, followed by TCOH, TCA and TCE. The CH patch test positive rate was 100% irrespective of CH concentrations (15%, 10% and 5%). The TCOH patch test positive rate was concentration-dependent (89.5%, 73.7% and 52.6% for 5%, 0.5% and 0.05%, respectively). Lower patch test positive rates were noted for TCA and TCE. All patch tests (including four allergens) were all negative in each of the 22 control subjects. None of the subjects of the validation group had a positive 15% CH patch test. Chloral hydrate seems to be the culprit causative compound of THS and type IV seems to be the major type of hypersensitivity of THS. The CH patch test could be potentially useful for screening workers at risk of THS.

Size Matters: Observed and Modeled Camouflage Response of European Cuttlefish (Sepia officinalis) to Different Substrate Patch Sizes during Movement

PubMed Central

Josef, Noam; Berenshtein, Igal; Rousseau, Meghan; Scata, Gabriella; Fiorito, Graziano; Shashar, Nadav

2017-01-01

Camouflage is common throughout the phylogenetic tree and is largely used to minimize detection by predator or prey. Cephalopods, and in particular Sepia officinalis cuttlefish, are common models for camouflage studies. Predator avoidance behavior is particularly important in this group of soft-bodied animals that lack significant physical defenses. While previous studies have suggested that immobile cephalopods selectively camouflage to objects in their immediate surroundings, the camouflage characteristics of cuttlefish during movement are largely unknown. In a heterogenic environment, the visual background and substrate feature changes quickly as the animal swim across it, wherein substrate patch is a distinctive and high contrast patch of substrate in the animal's trajectory. In the current study, we examine the effect of substrate patch size on cuttlefish camouflage, and specifically the minimal size of an object for eliciting intensity matching response while moving. Our results indicated that substrate patch size has a positive effect on animal's reflectance change, and that the threshold patch size resulting in camouflage response falls between 10 and 19 cm (width). These observations suggest that the animal's length (7.2–12.3 cm mantle length in our case) serves as a possible threshold filter below which objects are considered irrelevant for camouflage, reducing the frequency of reflectance changes—which may lead to detection. Accordingly, we have constructed a computational model capturing the main features of the observed camouflaging behavior, provided for cephalopod camouflage during movement. PMID:28144221

Size Matters: Observed and Modeled Camouflage Response of European Cuttlefish (Sepia officinalis) to Different Substrate Patch Sizes during Movement.

PubMed

Josef, Noam; Berenshtein, Igal; Rousseau, Meghan; Scata, Gabriella; Fiorito, Graziano; Shashar, Nadav

2016-01-01

Camouflage is common throughout the phylogenetic tree and is largely used to minimize detection by predator or prey. Cephalopods, and in particular Sepia officinalis cuttlefish, are common models for camouflage studies. Predator avoidance behavior is particularly important in this group of soft-bodied animals that lack significant physical defenses. While previous studies have suggested that immobile cephalopods selectively camouflage to objects in their immediate surroundings, the camouflage characteristics of cuttlefish during movement are largely unknown. In a heterogenic environment, the visual background and substrate feature changes quickly as the animal swim across it, wherein substrate patch is a distinctive and high contrast patch of substrate in the animal's trajectory. In the current study, we examine the effect of substrate patch size on cuttlefish camouflage, and specifically the minimal size of an object for eliciting intensity matching response while moving. Our results indicated that substrate patch size has a positive effect on animal's reflectance change, and that the threshold patch size resulting in camouflage response falls between 10 and 19 cm (width). These observations suggest that the animal's length (7.2-12.3 cm mantle length in our case) serves as a possible threshold filter below which objects are considered irrelevant for camouflage, reducing the frequency of reflectance changes-which may lead to detection. Accordingly, we have constructed a computational model capturing the main features of the observed camouflaging behavior, provided for cephalopod camouflage during movement.

Patch-test reaction patterns in patients with a predisposition to atopic dermatitis.

PubMed

Brasch, Jochen; Schnuch, Axel; Uter, Wolfgang

2003-10-01

Patients with a predisposition to atopic dermatitis often need to be patch tested in order to detect possible contact sensitization. However, it is unknown whether immunologic or other peculiarities of atopic skin are related to altered patch-test reaction patterns. Our study was aimed at answering this question, because patch-test reaction patterns are of considerable practical importance in the reading and interpretation of patch tests. Therefore, we compared patterns of patch-test reactions in patients with a predisposition to atopic dermatitis and in control patients matched for sex, age, reason for testing and test centre. Patch-test results from 9 centres (2322 patients with a disposition to atopic dermatitis and 2126 matched controls) were evaluated retrospectively. All patients were tested with nickel sulfate, fragrance mix, potassium dichromate, lanolin alcohol, formaldehyde and mercury ammonium chloride. Patch tests applied for 1 day with readings on days 1, 2 and 3 were evaluated in order to cover the early phase of the reactions. Not unexpectedly, we found that, compared to the matched controls, patients with a predisposition to atopic dermatitis tended to have more doubtful and irritant reactions on day 1. As a new observation, it turned out that they had less reactions of crescendo pattern and more strong reactions on day 3. All these differences were slight/insignificant. A higher skin irritability in patients with a predisposition to atopic dermatitis is a likely explanation. In conclusion, standard methods for patch testing can be applied in patients with a predisposition to atopic dermatitis, but minor differences in reaction patterns should be considered.

Content and reactivity to product perfumes in fragrance mix positive and negative eczema patients. A study of perfumes used in toiletries and skin-care products.

PubMed

Johansen, J D; Rastogi, S C; Andersen, K E; Menné, T

1997-06-01

The aim of the study was to investigate the elicitation potential of perfumes from 17 commonly sold lower-price cosmetic products. 8 of the perfumes were from stay-on cosmetics and 9 were from wash-off cosmetics. Each perfume was tested in 500 consecutive eczema patients, who also were tested with the European standard patch test series. 4.2% reacted to 1 or more of the wash-off product perfumes and 3.2% to 1 or more of the stay-on product perfumes. Concordant positive reactions between the fragrance mix and the product perfumes were found in 81.3% of positive reactions to the stay-on product perfumes and in 52.4% of the reactions to the wash-off product perfumes. Compared to the fragrance mix alone, only 1 additional case of contact allergy to the product perfumes was detected by balsam of Peru. Chemical analysis revealed that between 1 and 5 of the chemically-defined constituents of the fragrance mix were present in all of the product perfumes. Geraniol was found in 12 of the 17 perfumes and was most often detected. The concentration of the target fragrance materials ranged from 0.005%-1.35 w/v%. It is concluded that the allergenic constituents of the fragrance mix are impossible to avoid if perfumed cosmetics are used. Furthermore, patients suspected of perfume allergy need to be tested with their own perfumed products, as far from all cases of perfume allergy are detected by the fragrance mix and/or balsam of Peru in the European standard patch test series.

Epoxy-based production of wind turbine rotor blades: occupational contact allergies.

PubMed

Pontén, Ann; Carstensen, Ole; Rasmussen, Kurt; Gruvberger, Birgitta; Isaksson, Marléne; Bruze, Magnus

2004-03-01

An industry producing rotor blades for wind turbines with an epoxy-based technology had experienced an increasing number of workers with dermatitis, among whom the frequency of occupational contact allergy (OCA) was suspected to be underestimated. To investigate the frequency of OCA by patch-testing with a specially profiled occupational patch test series. In a blinded study design, 603 workers were first interviewed and thereafter clinically examined. Based on a history of work-related skin disease, clinical findings of dermatitis, or both, 325 (53.9%) of the workers were patch-tested with an occupational patch test series and the European Standard patch test series. Of the 603 investigated workers, 10.9% had OCA and 5.6% had contact allergy to epoxy resin in the standard test series. Contact allergy to amine hardeners/catalysts was found in 4.1% of the workers. Among the workers with OCA, 48.5% reacted to work material other than epoxy resin in the European Standard patch test series. Approximately 50% of the workers with OCA would not have been detected if only the European Standard patch test series had been used.

Intradermal Vaccination With Adjuvanted Ebola Virus Soluble Glycoprotein Subunit Vaccine by Microneedle Patches Protects Mice Against Lethal Ebola Virus Challenge.

PubMed

Liu, Ying; Ye, Ling; Lin, Fang; Gomaa, Yasmine; Flyer, David; Carrion, Ricardo; Patterson, Jean L; Prausnitz, Mark R; Smith, Gale; Glenn, Gregory; Wu, Hua; Compans, Richard W; Yang, Chinglai

2018-06-08

In this study, we investigated immune responses induced by purified Ebola virus (EBOV) soluble glycoprotein (sGP) subunit vaccines via intradermal immunization with microneedle (MN) patches in comparison with intramuscular (IM) injection in mice. Our results showed that MN delivery of EBOV sGP was superior to IM injection in eliciting higher levels and longer lasting antibody responses against EBOV sGP and GP antigens. Moreover, sGP-specific immune responses induced by MN or IM immunizations were effectively augmented by formulating sGP with a saponin-based adjuvant, and they were shown to confer complete protection of mice against lethal mouse-adapted EBOV (MA-EBOV) challenge. In comparison, mice that received sGP without adjuvant by MN or IM immunizations succumbed to lethal MA-EBOV challenge. These results show that immunization with EBOV sGP subunit vaccines with adjuvant by MN patches, which have been shown to provide improved safety and thermal stability, is a promising approach to protect against EBOV infection.

Quantitative repeated open application testing with a rinse-off product in methyldibromo glutaronitrile-sensitive patients: results of the IVDK.

PubMed

Heratizadeh, Annice; Killig, Claudia; Worm, Margitta; Soost, Stephanie; Simon, Dagmar; Bauer, Andrea; Mahler, Vera; Schuster, Christian; Szliska, Christiane; Frambach, Yvonne; Eben, Ricarda; Werfel, Thomas; Uter, Wolfgang; Schnuch, Axel

2010-06-01

While the use of methyldibromo glutaronitrile (MDBGN) in leave-on products is clearly associated with high sensitization or elicitation risk, such a clear-cut relation could be questioned with regard to rinse-off products. The objective of this study was to find a maximum non-eliciting concentration for rinse-off products in MDBGN patch test-positive patients. We performed a use-related test [repeated open application test (ROAT)] in patients sensitized to MDBGN with a liquid soap containing three concentrations of MDBGN (50, 200, and 400 p.p.m. MDBGN, respectively). The soap at 50 p.p.m. was used twice daily for 4 weeks. If no reaction of the skin was observed, the product with the next higher concentration was used for another 4 weeks, etc. In total, 32/37 evaluated cases [86.5%; lower exact one-sided 95% confidence limit (CL): 73.7%] did not react to any of the preparations. The remaining reacted as follows: 1/37 reacted to 50 p.p.m., 3/37 to 200 p.p.m., and 1/37 to 400 p.p.m. The cumulative non-response to 50 p.p.m. was 97.3% (lower CL: 87.8%). The majority of subjects sensitized to MDBGN-tolerated rinse-off products containing a maximum concentration of 400 p.p.m. A concentration in rinse-off products in the range of 50 p.p.m. could be regarded as safe for most individuals already sensitized. These concentrations will presumably prevent induction (sensitization) also.

Trichloroethylene Hypersensitivity Syndrome Is Potentially Mediated through Its Metabolite Chloral Hydrate

PubMed Central

Huang, Yongshun; Xia, Lihua; Wu, Qifeng; Zeng, Zifang; Huang, Zhenlie; Zhou, Shanyu; Jin, Jiachun; Huang, Hanlin

2015-01-01

Background We documented previously the entity of trichloroethylene (TCE) hypersensitivity syndrome (THS) in occupational workers. Objectives To identify the culprit causative compound, determine the type of hypersensitivity of THS, and establish a screening test for subjects at risk of THS. Methods TCE and its main metabolites chloral hydrate (CH), trichloroethanol (TCOH) and trichloroacetic acid (TCA) were used as allergens at different concentrations in skin patch tests. The study included 19 case subjects diagnosed with occupational THS, 22 control healthy workers exposed to TCE (exposure >12 weeks), and 20 validation new workers exposed to TCE for <12 weeks free of THS. All subjects were followed-up for 12 weeks after the patch test. Results The highest patch test positive rate in subjects with THS was for CH, followed by TCOH, TCA and TCE. The CH patch test positive rate was 100% irrespective of CH concentrations (15%, 10% and 5%). The TCOH patch test positive rate was concentration-dependent (89.5%, 73.7% and 52.6% for 5%, 0.5% and 0.05%, respectively). Lower patch test positive rates were noted for TCA and TCE. All patch tests (including four allergens) were all negative in each of the 22 control subjects. None of the subjects of the validation group had a positive 15% CH patch test. Conclusions Chloral hydrate seems to be the culprit causative compound of THS and type IV seems to be the major type of hypersensitivity of THS. The CH patch test could be potentially useful for screening workers at risk of THS. PMID:26020924

Environmental contact factors in eczema and the results of patch testing Chinese patients with a modified European standard series of allergens.

PubMed

Li, Lin-Feng; Guo, Jing; Wang, Jing

2004-07-01

Environmental contact factors in eczema were investigated in China by clinical questionnaire and patch testing patients with a modified European standard series of allergens. 217 consecutive eczema patients were studied. Contact dermatitis (CD) was clinically diagnosed in 30% of the patients. Among the patients patch tested, 46 patients had clinically diagnosed allergic CD (ACD), 20 patients clinically had non-ACD (NACD) (including 16 cases of irritant contact dermatitis, 1 case of phototoxic contact reaction and 3 cases of asteatotic eczema) and 115 patients had clinically suspected ACD. 45 patients (98%) in the ACD group went on to have relevant patch test results. The most common ACD was from metals, fragrance materials, cosmetics and rubber materials. The most common contact allergens identified were nickel, fragrance mix, para-phenylenediamine (PPD), carba mix and thimerosal. No adverse reactions were observed to patch testing, except for pruritus in patch-test-positive patients. The positive rate of patch testing in ACD was much higher than that in NACD (98% versus 15%, P < 0.05, chi(2)-test). 60 (28%) patients had facial dermatitis (FD). Among these, 20 (33%) were confirmed as having ACD. 48 (22%) patients had hand dermatitis (HD). Among these, 7 (15%) were confirmed as having ACD. Fewer patients were confirmed as having ACD in the HD group than in the FD (15% versus 33%, P < 0.05, chi(2)-test). Although the difference was not significant, the total positivity rate in the HD group (55%) was lower than in the other groups. 65 (30%) patients had unclassified endogenous eczema (UEE). The total positive rate of patch testing in the UEE group (56%) was no different from that in the FD or HD groups. However, the relevance of positive patch tests was hard to determine in UEE. These results indicate that CD is common in eczema; relatively more patients with FD have ACD, while other factors, such as irritation, may play more of a role in HD. The total positive rate of patch testing in the UEE group was no different from that in the FD or HD groups, suggesting that patch testing should be stressed in UEE and the relevance of positive patch test results in UEE should be studied further. It is effective and safe to patch eczema patients with a modified European standard series of allergens in China.

Hydrodynamic Mediation of Killifish Predation on Infaunal Polychaetes

NASA Astrophysics Data System (ADS)

Hentschel, B. T.; Hayman, N. T.; Anderson, T. W.

2016-02-01

To explore predator-prey interactions between California killifish (Fundulus parvipinnis) and spionid polychaetes (Polydora cornuta and Streblospio benedicti) in tidal creeks, we conducted a laboratory flume experiment to quantify whether killifish prey-patch selectivity varies with flow speed. The flume included a 300-cm2 area of defaunated sediment within which we centrally positioned 24 P. cornuta, 24 S. benedicti, or no worms as a prey-free control. We videotaped groups of three killifish for 50 min at one of six unidirectional flow speeds (3, 6, 9, 12, 15, or 18 cm/s measured 1.5 cm above bottom) and recorded their bite rate anywhere in the sediment area vs. bites directed at the central prey patch (98 cm2). Each flow speed and prey treatment was replicated by four independent flume runs (i.e., 72 total flume runs). The percentage of bites directed at the central patch varied significantly with flow speed and worm presence. With defaunated sediment only, 33% of bites were directed at the central patch at all flow speeds, consistent with a null model of non-selective foraging. When either worm species inhabited the central patch, 65% of bites were directed at the central patch at 3 and 6 cm/s, and patch selectivity declined linearly as flow increased. Despite differences in morphology and behavior, the two prey species elicited similar foraging activity by killifish. We pooled the P. cornuta and S. benedicti treatments to determine the flow speed at which prey-patch selectivity by killifish became statistically indistinguishable from non-selective biting in the absence of prey. At flow speeds of 3, 6, and 9 cm/s, the percentage of bites located in the 98-cm2 patch was significantly greater when live worms were present compared to the prey-free controls. At 12, 15, and 18 cm/s, there was not a significant difference between the control patches and those containing live worms, indicating 12 cm/s is a flow threshold above which killifish cannot selectively forage on dense patches of infauna.

Resolving the 'nitrogen paradox' of arbuscular mycorrhizas: fertilization with organic matter brings considerable benefits for plant nutrition and growth.

PubMed

Thirkell, Tom J; Cameron, Duncan D; Hodge, Angela

2016-08-01

Arbuscular mycorrhizal fungi (AMF) can transfer nitrogen (N) to host plants, but the ecological relevance is debated, as total plant N and biomass do not generally increase. The extent to which the symbiosis is mutually beneficial is thought to rely on the stoichiometry of N, phosphorus (P) and carbon (C) availability. While inorganic N fertilization has been shown to elicit strong mutualism, characterized by improved plant and fungal growth and mineral nutrition, similar responses following organic N addition are lacking. Using a compartmented microcosm experiment, we determined the significance to a mycorrhizal plant of placing a (15) N-labelled, nitrogen-rich patch of organic matter in a compartment to which only AMF hyphae had access. Control microcosms denied AMF hyphal access to the patch compartment. When permitted access to the patch compartment, the fungus proliferated extensively in the patch and transferred substantial quantities of N to the plant. Moreover, our data demonstrate that allowing hyphal access to an organic matter patch enhanced total plant N and P contents, with a simultaneous and substantial increase in plant biomass. Furthermore, we demonstrate that organic matter fertilization of arbuscular mycorrhizal plants can foster a mutually beneficial symbiosis based on nitrogen transfer, a phenomenon previously thought irrelevant. © 2015 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

Pesticide patch test series for the assessment of allergic contact dermatitis among banana plantation workers in panama.

PubMed

Penagos, Homero; Ruepert, Clemens; Partanen, Timo; Wesseling, Catharina

2004-09-01

Irritant contact dermatitis and allergic contact dermatitis (ACD) are frequent among agricultural workers and require targeted interventions. Patch testing is necessary for differential diagnosis, but patch testing with pesticides is uncommon. This study explores the frequency of ACD and sensitization to pesticides among highly exposed banana plantation workers. Frequently and recently used pesticides on banana plantations in Divala, Panama, were documented. A pesticide patch test tray specific for this population was prepared. A structured interview was administered to 366 participants, followed by a complete skin examination. The pesticide patch test series, as well as a standard patch test series, was applied to 37 workers with dermatoses likely to be pesticide related and to 23 control workers without dermatoses. The pesticide patch tests identified 15 cases (41%) of ACD (20 positive reactions) among the 37 workers diagnosed with pesticide dermatosis. Three controls had allergic reactions to pesticides (4 positive reactions). The pesticides were carbaryl (5 cases), benomyl (4 cases), ethoprophos (3), chlorothalonil (2), imazalil (2), glyphosate (2), thiabendazole (2), chlorpyrifos (1), oxyfluorfen (1), propiconazole (1), and tridemorph (1). Ethoprophos and tridemorph had not been previously identified as sensitizers. Thus, the prevalence of ACD was 0.03 (15 of 366). On the basis of observed prevalences of positive patch-test reactions among the subgroups with and without dermatoses, we estimated that > or = 16% of the entire population may be sensitized to pesticides. Sensitization to pesticides among banana plantation workers is a frequent occupational health problem. Pesticide patch test trays should be used in assessing skin diseases in highly exposed workers.

Urushiol Patch Test Using the T.R.U.E. TEST System.

PubMed

Kim, Yesul; Longenecker, Amy; ElSohly, Mahmoud A; Gul, Waseem; Hage, Raymond J; Hamann, Curtis P; Marks, James G

Poison ivy, poison oak, and poison sumac are the most common causes of allergic contact dermatitis in North America. Although extensive efforts have been made to develop therapies that prevent and treat allergic contact dermatitis to these plants, there lacks an entirely effective method, besides complete avoidance. Efforts to develop a more effective preventive therapy, such as a vaccine, are ongoing. To accurately evaluate the efficacy of these new therapies, an appropriate assessment tool is needed. The aim of this study was to evaluate the safety and appropriate doses of urushiol required for a patch test based on the hydrogel delivery system of the Thin-Layer Rapid Use Epicutaneous Patch Test. Nine subjects were patch tested with various doses of urushiol and a negative control on day 0. Patch test sites were inspected for any local reaction on days 2, 4, 7, 14, and 21 after the initial exposure and graded by standard morphology. All 9 subjects did not have any significant adverse effects. The urushiol patch test using the hydrogel delivery method demonstrated urushiol sensitivity. All doses of urushiol resulted in a local reaction, and severity of reactions was correlated with dosage of urushiol used in the patch test.

Photo-patch and patch tests in patients with dermatitis over the photo-exposed areas: A study of 101 cases from a tertiary care centre in India.

PubMed

Sharma, Vinod Kumar; Bhari, Neetu; Wadhwani, Ashok Roopchand; Bhatia, Riti

2018-02-01

Many patients with dermatitis over photo-exposed body areas are positive to many contact allergens and have a pre-existing allergic contact dermatitis. This study included patients who presented to a tertiary centre in India with dermatitis on photo-exposed body areas suspected of chronic actinic dermatitis. Their detailed histories were recorded and cutaneous and systemic examinations were performed. Patch testing was done in all the patients and photo-patch testing was carried out in 86 patients. Altogether 101 patients were included (69 males, 32 females). The most common presentation was lichenified hyperpigmented plaques on the photo-exposed sites. Photosensitivity was recorded in 64 (63%) patients and summer exacerbation in 52 (52%). Exposure to the Parthenium hysterophorus weed was recorded in 70 (69%) patients, 27 (26.7%) had a history of hair dye application and 20 (20%) had a history of atopy. Photo-patch test was positive in 11 (12.8%) patients and patch testing was positive in 71 (70%). Parthenium hysterophorus was the most common allergen implicated and was positive in three (4%) photo-patch and 52 (52%) patch tests. Other positive photo-patch test allergens were perfume mix, balsam of Peru, thiuram mix, Compositae mix and promethazine hydrochloride. Other common patch test allergens were parthenolide, colophony, fragrance mix and p-phenylenediamine (PPD) base. In the Indian population parthenium and perfume mix are the most common photoallergens in patients with dermatitis over photo-exposed areas, while parthenium, colophony, fragrance mix and PPD are the common positive allergens. © 2016 The Australasian College of Dermatologists.

Attitudes about Advances in Sweat Patch Testing in Drug Courts: Insights from a Case Study in Southern California

ERIC Educational Resources Information Center

Polzer, Katherine

2010-01-01

Drug courts are reinventing the drug testing framework by experimenting with new methods, including use of the sweat patch. The sweat patch is a band-aid like strip used to monitor drug court participants. The validity and reliability of the sweat patch as an effective testing method was examined, as well as the effectiveness, meaning how likely…

The reactivity of the back revisited. Are there differences in reactivity in different parts of the back?

PubMed

Björk, Ann-Kristin; Bruze, Magnus; Engfeldt, Malin; Nielsen, Christel; Svedman, Cecilia

2017-01-01

In the contact dermatitis literature, it is regularly stated that the patch test reactivity on various areas of the back differs, which might have a large impact on the reproducibility of patch testing. To investigate the reproducibility of patch testing on the upper back with regard to the left as opposed to the right side, and the medial as opposed to the lateral part of the upper back. The reproducibility over time and with regard to the reactivity pattern was also investigated. Thirty-one subjects with contact allergy to the metals gold (n = 19) or nickel (n = 12) were patch tested with serial dilutions, in triplicate applications, on different locations on the upper back. The Friedman test was used for statistical calculations. No significant differences in the reactivity of the back were found. In all gold-allergic patients and 11 of 12 nickel-allergic patients, the allergy could be reproduced with regard to previous patch testing, but the degree of reactivity differed. When a high level of standardization of the patch test technique with the same test system was used, there were no differences in patch test reactions and sites of application on the upper back. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation and Management of Patch Test-Negative Patients With Generalized Dermatitis.

PubMed

Spiker, Alison; Mowad, Christen M

Patients with generalized dermatitis are common in dermatology practices. Allergic contact dermatitis is often suspected, and patients frequently undergo patch testing. When the patch testing result is negative, further evaluation and management of these patients are challenging. The purpose of this study was to survey members of the American Contact Dermatitis Society regarding the evaluation and management of patch test-negative patients with generalized dermatitis. Generalized dermatitis was the most common term identified for patch test-negative patients with diffuse dermatitis. After having negative expanded patch testing results, most physicians proceeded with additional testing including skin biopsy, complete blood cell count with differential, and liver and renal function tests. The most commonly used systemic treatment is prednisone, followed by methotrexate. Narrow-band ultraviolet B (UVB) is the most commonly used light source. Antihistamines are frequently prescribed. Food allergy is not felt to be causative. This cohort of patients experiences significant impairment in quality of life, stress on personal relationships, and time off work. The management of patch test-negative patients with generalized dermatitis is challenging. This study provides insight into management of these complex patients. It also demonstrates practice gaps in the management of these patients, indicating a need for further studies to direct the evaluation and management of this patient population.

Air-borne contact dermatitis caused exclusively by xanthium strumarium.

PubMed

Pasricha, J S; Verma, K K; D'Souza, P

1995-01-01

Most cases having air-borne contact dermatitis (ABCD) in India are considered to be caused by Parthenium hysterophorus. In some cases however, other plants have also been noticed to give positive patch test reactions. We are reporting two cases presenting as ABCD who showed positive patch tests with Xanthium strumarium while the patch tests with Parthenium hysterophorus were negative. It is therefore necessary to realise that every case of ABCD is not caused by Parthenium, and patch testing with Parthenium alone can lead to serious mistakes.

Allergic contact dermatitis from ophthalmic products: can pre-treatment with sodium lauryl sulfate increase patch test sensitivity?

PubMed

Corazza, Monica; Virgili, Annarosa

2005-05-01

In patients suspected of allergic contact dermatitis because of topical ophthalmic medicaments, patch tests performed with patients' own products are often negative. The irritant anionic surfactant sodium lauryl sulfate (SLS) may alter the stratum corneum and increase antigen penetration. Pre-treatment of the skin with SLS 0.5% for 24 h was performed in the sites of patch tests with patients' own products in 15 selected patients. In patients previously negative to their own products tested with conventional patch tests, SLS pre-treatment showed 6 new relevant positive reactions and induced a stronger positive reaction in 1 patient. SLS pre-treatment could be proposed as an alternative promising method, which may increase sensitivity of patch tests with patients' own products.

Inward current activated by carbachol in rat intestinal smooth muscle cells.

PubMed Central

Ito, S; Ohta, T; Nakazato, Y

1993-01-01

1. Carbachol (0.1 mM or 10 microM)-evoked inward currents were studied with standard and perforated whole-cell patch clamp techniques in smooth muscle cells isolated from rat small intestine. The intracellular free Ca2+ concentration was monitored simultaneously with the fura-2 method. 2. With a K(+)-containing pipette solution, carbachol produced an inward current at -60 mV and a large outward current at -20 mV. 3. When NaCl was substituted for KCl in the external and pipette solutions, carbachol elicited inward currents at holding potentials more inside-negative than 0 mV. The reversal potential of the carbachol-induced current altered when external chloride (-0.9 mV) was replaced by iodide (-21.2 mV), thiocyanate (-27.0 mV) and glutamate (18.2 mV). The carbachol-induced current at -60 mV was slightly decreased by the replacement of external NaCl with Tris-Cl. 4. The carbachol-induced inward current at -60 mV was accompanied by an increase in the intracellular concentration of free Ca2+. Both responses to carbachol were observed 2 min after exposure of the cells to a Ca(2+)-free solution containing 2 mM EGTA. 5. Intracellular application of heparin inhibited the inward current and Ca2+ transient responses to carbachol but not those to caffeine (10 mM). An inward current and Ca2+ transient were elicited after the patch membrane was ruptured at -60 mV, using a patch pipette containing inositol 1,4,5-trisphosphate (InsP3). 6. It is concluded that the carbachol-induced inward current is due to increases in membrane Cl- and Na+ conductances. Ca2+ released from InsP3-sensitive stores may play a role in increasing both conductances. PMID:7508506

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

PubMed

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.

Pediatric Baseline Patch Test Series: Initial Findings of the Pediatric Contact Dermatitis Workgroup.

PubMed

Yu, JiaDe; Atwater, Amber Reck; Brod, Bruce; Chen, Jennifer K; Chisolm, Sarah S; Cohen, David E; de la Feld, Salma; Gaspari, Anthony A; Martin, Kari Lyn; Montanez-Wiscovich, Marjorie; Sheehan, Michael; Silverberg, Nanette; Lugo-Somolinos, Aida; Thakur, Binod K; Watsky, Kalman; Jacob, Sharon E

2018-06-21

Allergic contact dermatitis is a challenging diagnostic problem in children. Although epicutaneous patch testing is the diagnostic standard for confirmation of contact sensitization, it is less used in children by dermatologists treating children, pediatric dermatologists, and pediatricians, when compared with adult practitioners. The aim of the study was to create and evaluate standardization of a pediatric patch test series for children older than 6 years. We surveyed dermatologists and allergists conducting epicutaneous patch testing in children attending the 2017 American Contact Dermatitis Society meeting held in Washington, DC. This was followed by discussion of collected data and consensus review by a pediatric contact dermatitis working group at the conference. A baseline pediatric patch test panel was established through working group consensus.

Health hazard evaluation report HETA 85-060-1670, City of Norwood, Norwood, Ohio. [Toner powder exposure

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

Ruhe, R.L.; Bennett, D.

1986-02-01

Following a request from the Health Commissioner of Norwood, Ohio, employee exposure to toner powder used in Norwood Senior High Media Center photocopying machine was investigated. Personal and area air samples for total particulates were collected on preweighed filters and total sample weights determined. Indicator tube sampling was done for carbon monoxide and ozone. Medical interviews were conducted with three media center workers to elicit work related symptomatology. Exposure to total particulate ranged from less than the detection limit to 0.02 mg/m/sup 3/. Carbon monoxide and ozone were nondetectable. Two employees reported no symptoms associated with work. After operating themore » copy machine for 3 weeks, the third employee developed hives on both hands progressing to the earlobes and right cheek. Her condition improved on weekends. She also had a cough and shortness of breath when working with the duplicator. No positive response to patch testing was seen, but the employee developed cough, tearing eyes, and itching 2 hours after patch application. The authors conclude that one employee suffered an allergic reaction precipitated by materials inhaled in the duplicator area. It is recommended that this employee not use this machine, and improved ventilation be provided for the entire media center.« less

Prevalence of benzocaine and lidocaine patch test sensitivity in Denmark: temporal trends and relevance.

PubMed

Thyssen, Jacob P; Engkilde, Kåre; Menné, Torkil; Johansen, Jeanne D

2011-08-01

BACKGROUND. Allergens included in the European baseline series should result in positive patch test reactions in at least 1% of a patch test population. Inclusion of local anaesthetics other than benzocaine in the baseline series has previously been debated. To investigate temporal trends of benzocaine and lidocaine allergy in dermatitis patients who underwent routine patch testing in a tertiary referral patch test centre, and to clarify and discuss whether lidocaine and benzocaine should be included in routine series. Dermatitis patients who underwent routine patch testing with benzocaine as a part of the European baseline series between 1985 and 2010 (n = 19 347) and dermatitis patients who underwent routine patch testing with lidocaine between 1994 and 2001 (n = 6265) and between 2007 and 2009 (n = 1360) were included. The overall prevalences of contact allergy were 0.5% (benzocaine), 0.3% (lidocaine for the period 1994-2001), and 0.14% (lidocaine for the period 2007-2009). Current relevance was observed in 10% of those with benzocaine allergy and in 5% of those with lidocaine allergy. Benzocaine and lidocaine allergy is infrequent in Danish dermatitis patients. Lidocaine should only be used for aimed testing, and benzocaine should be removed from the baseline series used in Denmark. © 2011 John Wiley & Sons A/S.

Comparison of reactivity to a metallic disc and 2% aluminium salt in 366 children, and reproducibility over time for 241 young adults with childhood vaccine-related aluminium contact allergy.

PubMed

Gente Lidholm, Anette; Inerot, Annica; Gillstedt, Martin; Bergfors, Elisabet; Trollfors, Birger

2018-07-01

An aluminium hydroxide-adsorbed pertussis toxoid vaccine was studied in 76 000 children in the 1990s in Gothenburg, Sweden. Long-lasting itchy subcutaneous nodules at the vaccination site were seen in 745 participants. Of 495 children with itchy nodules who were patch tested for aluminium allergy, 377 were positive. In 2007-2008, 241 of the positive children were retested. Only in one third were earlier positive results reproduced. To further describe patch test reactions to different aluminium compounds in children with vaccine-induced aluminium allergy. Positive patch test results for metallic aluminium (empty Finn Chamber) and aluminium chloride hexahydrate 2% petrolatum (pet.) were analysed in 366 children with vaccine-induced persistent itching nodules tested in 1998-2002. Of those, 241 were tested a second time (2007-2008), and the patch test results of the two aluminium preparations were analysed. Patch testing with aluminium chloride hexahydrate 2% pet. is a more sensitive way to diagnose aluminium contact allergy than patch testing with metallic aluminium. A general decrease in the strength of reactions to both aluminium preparations in 241 children tested twice was observed. Aluminium contact allergy can be diagnosed by patch testing without using metallic aluminium. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Our experience with atopy patch tests with aeroallergens.

PubMed

Celakovská, Jarmila; Ettlerová, Kvetuse; Ettler, Karel; Vanecková, Jaroslava

2013-01-01

Aim of our study was to evaluate the importance of atopy patch testing with aeroallergens as a diagnostic method in patients suffering from atopic dermatitis. The complet dermatological and allergological examinations were performed in 29 patients; 10 men, 19 women with the average age of 27.8 years, min. 17, max. 57 years; with the median SCORAD 24.2 points, s.d. 13.3 points. Wormwood, grass, dog dander, cat dander, dermatophagoides pharinae, dermatophagoides pteronyssinus and birch pollen were examined in diagnostic procedures. Skin prick tests, specific IgE were examined; the atopy patch tests were performed with aeroallergens for skin prick tests in concentration 1 x skin prick tests. Specific IgE and skin prick tests to one or more tested aeroallergens were positive altogether in 27 patients; atopy patch tests were positive only in one of these patients. For atopy patch testing with aeroallergens the concentration of 1 x skin prick tests is low to confirme the eczematic reaction in patients suffering from allergy to inhallant allergens.

Mechanisms of gastroprotection by transdermal nitroglycerin in the rat

PubMed Central

Calatayud, Sara; Sanz, María-Jesús; Canet, Amparo; Bello, Regina; de Rojas, Francisco Díaz; Esplugues, Juan V

1999-01-01

Nitric oxide (NO) donors prevent experimentally-induced gastric mucosal damage, but their clinical utility is limited by short duration of action or unsuitability of the pharmaceutical form employed. This study analyses the gastroprotection elicited by a clinically used mode of continuous administration of an NO donor, namely the nitroglycerin patch. Application to rats of a transdermal patch that releases doses of nitroglycerin comparable to those used in man (40, 80, 160 and 400 ng min−1 rat−1) reduced gastric damage induced by indomethacin (25 mg kg−1, p.o. or s.c.). The nitroglycerin patch (160 ng  min−1 rat−1) also diminished damage by oral administration (1 ml) of acidified bile salts (100 mg kg−1 taurocholic acid in 150 mM HCl) or 50% ethanol. Transdermal nitroglycerin (160 ng min−1 rat−1) did not influence basal gastric blood flow, as measured by lasser-doppler flowmetry, but prevented its reduction by indomethacin. Transdermal nitroglycerin (160 ng min−1 rat−1) prevented in vivo leukocyte rolling and adherence in the rat mesentery microvessels superfused with indomethacin, as evaluated by intravital microscopy. The transdermal nitroglycerin patch protects the gastric mucosa from damage by mechanisms that involve maintenance of mucosal blood flow and reduction of leukocyte-endothelial cell interaction. PMID:10455256

Use of patch testing for the diagnosis of abacavir-related hypersensitivity reaction in HIV patients.

PubMed

Giorgini, S; Martinelli, C; Tognetti, L; Carocci, A; Giuntini, R; Mastronardi, V; Torricelli, F; Leoncini, F; Lotti, T

2011-01-01

The use of antiretroviral drug abacavir (ABC) has been often associated with cutaneous hypersensitivity reactions, the majority being severe. The present study discusses the issues of patch testing associated with pharmacogenetic screening in light of the development of abacavir hypersensitivity reactions (HSRs). The present authors classified 100 patients into three groups: 20 patients (group A) had experienced a hypersensitivity reaction when treated with highly active antiretroviral therapy (HAART) including ABC; 60 HIV-positive patients (group B) were receiving HAART scheme including ABC; 20 HIV-negative patients acted as control group (group C). Patients of group A and B were patch tested with ABC as such, then with an ABC extract diluted to 1 and 10% in petrolatum. Group C patients underwent patches with petrolatum only. A biopsy of the lesion was performed in those patients who showed a positive skin reaction. All patients had been tested for HLA-B5701. A correlation between positive ABC-patch testing and HLA-B5701 was found in 50% of patients enrolled in group A, while in group B and C, all patients tested negative for both genetic marker and ABC-patch testing. Histopathology findings confirmed a vigorous CD4+ and CD8+ cellular response that is compatible with HSR. Patch testing is a safe and sensitive method that can be used for to confirm or exclude any correlation between abacavir and hypersensitivity skin reactions in patients who have been previously treated with abacavir during HAART. Correlation between patch test, immunohistochimical, and genetic tests results shows that genetic testing increases the possibility to identify patients with a true reaction. © 2012 Wiley Periodicals, Inc.

Allergic contact dermatitis to benzocaine: the importance of concomitant positive patch test results.

PubMed

González-Rodríguez, A J; Gutiérrez-Paredes, E M; Revert Fernández, Á; Jordá-Cuevas, E

2013-03-01

Local anesthetics are widely used in clinical practice, and adverse effects are not uncommon. Delayed hypersensitivity reactions are among the most common effects, but immediate-type reactions may also occur. Patch testing should be considered in patients with hypersensitivity reactions. We present a case of allergic contact dermatitis to benzocaine that was detected incidentally by patch testing and highlight the importance of correctly interpreting patch test results when there are concomitant positive reactions. Copyright © 2011 Elsevier España, S.L. and AEDV. All rights reserved.

PATIENTS' KNOWLEDGE OF MEDICAL PATCHES IN HUNGARY.

PubMed

Somogyi, Orsolya; Zelko, Romana

2016-11-01

Transdermal therapy with medical patches is a simple possibility in home medication. As the correct use of patches has a decisive impact from the point of its modulator effect.A questionnaire survey was developed to explore level of patients' knowledge of the correct use of transdermal patches. A survey was administered in thirteen Hungarian community pharmacies from October of 2012 to May of 2015. Most of the participants, men and women over 18 years of age (n = 233), used major analgesic patches (fentanyl); the remainder were given nitroglycerin, NSAID analgesics patches during the survey. For the hypothesis testing it was assumed that men were more likely to use a razor for skin depilation before patch application than women as their denser pelage hinders patch adhesion. The hypothesis testing showed no significant gender difference in razor use (X² = 0.201; p = 0.654). Pharmacists should direct patients to avoid using soap for skin cleansing before patch application because only 22 percent of the participants always avoided its use. Since only 9 tests were flawless from 233 completed questionnaires. Many patients do not understand how to correctly apply a transdermal dosage patch. Pharmacists should teach their correct application based on results.

Contact Urticaria to Nickel: A Series of 11 Patients Who Were Prick Test Positive and Patch Test Negative to Nickel Sulfate 2.5% and 5.0.

PubMed

Saluja, Sandeep S; Davis, Crystal L; Chong, Tracie A; Powell, Douglas L

2016-01-01

Nickel is the most common allergen found by patch testing; however, not all cases of nickel allergy are type 4 (delayed) allergies. Contact urticaria (CU) to nickel (immediate reaction) has been reported; however, few seem to evaluate it as per a recent published survey of American Contact Dermatitis Society members. The aim of the study was to present a series of patients who had clinical histories suggestive of nickel allergy and yet were patch test negative but prick test positive to nickel, thus demonstrating CU. We reviewed the charts of 11 patients who were patch test negative but prick test positive. All 11 patients demonstrated evidence of CU by prick testing (or closed chamber test in 1). None were patch test positive to nickel 2.5% or 5.0%. Four patients' histories mentioned reactions to various jewelry/earrings within minutes, whereas 2 histories mentioned reacting within a few hours. These histories are consistent with CU. Others (except 1 patient) recalled reacting to jewelry/earrings but did not recall a time frame. Our series suggests that CU to nickel may be far more common than anticipated and should be evaluated with prick testing when patients' history suggests nickel allergy and yet they are patch test negative.

The Effects of Nicotinic and Muscarinic Receptor Activation on Patch-Clamped Cells in the Optic Tectum of Rana Pipiens

PubMed Central

Yu, C.-J.; Debski, E. A.

2008-01-01

Both nicotinic and muscarinic cholinergic receptors are present in the optic tectum. To begin to understand how the activation of these receptors affects visual activity patterns, we have determined the types of physiological responses induced by their activation. Using tectal brain slices from the leopard frog, we found that application of nicotine (100 μM) evoked long-lasting responses in 60% of patch-clamped tectal cells. Thirty percent of these responses consisted of an increase in spontaneous postsynaptic currents (sPSCs) and had both a glutamatergic and GABAergic component as determined by the use of 6-cyano-7-nitroquinoxaline-2,3-dione (50 μM) and bicuculline (25 μM), respectively. Remaining response types consisted of an inward membrane current (16%) and an increase in sPSCs combined with an inward membrane current (14%). All responses could be elicited in the presence of tetrodotoxin (0.5 μM). Muscarinic receptor-mediated responses, induced by carbachol (100 μM) application after nicotinic receptor desensitization, produced responses in 70% of tectal cells. In contrast to responses elicited by nicotine, carbachol-induced responses could be evoked multiple times without significant decrement. Responses consisted of either an outward current (57%), a decrease in sPSCs (5%) or an increase in sPSCs, with (almost 6%) or without (almost 3%) an outward current. The response elicited by carbachol was not predicted by the response of the cell to nicotine. Our results suggest that nicotinic receptors are found predominantly at presynaptic locations in the optic tectum while muscarinic receptors are most often present at postsynaptic sites. We conclude that both of these receptor types could substantially modulate visual activity by changing either the input to tectal neurons or the level of their response to that input. PMID:12676145

The effects of nicotinic and muscarinic receptor activation on patch-clamped cells in the optic tectum of Rana pipiens.

PubMed

Yu, C-J; Debski, E A

2003-01-01

Both nicotinic and muscarinic cholinergic receptors are present in the optic tectum. To begin to understand how the activation of these receptors affects visual activity patterns, we have determined the types of physiological responses induced by their activation. Using tectal brain slices from the leopard frog, we found that application of nicotine (100 microM) evoked long-lasting responses in 60% of patch-clamped tectal cells. Thirty percent of these responses consisted of an increase in spontaneous postsynaptic currents (sPSCs) and had both a glutamatergic and GABAergic component as determined by the use of 6-cyano-7-nitroquinoxaline-2,3-dione (50 microM) and bicuculline (25 microM), respectively. Remaining response types consisted of an inward membrane current (16%) and an increase in sPSCs combined with an inward membrane current (14%). All responses could be elicited in the presence of tetrodotoxin (0.5 microM). Muscarinic receptor-mediated responses, induced by carbachol (100 microM) application after nicotinic receptor desensitization, produced responses in 70% of tectal cells. In contrast to responses elicited by nicotine, carbachol-induced responses could be evoked multiple times without significant decrement. Responses consisted of either an outward current (57%), a decrease in sPSCs (5%) or an increase in sPSCs, with (almost 6%) or without (almost 3%) an outward current. The response elicited by carbachol was not predicted by the response of the cell to nicotine. Our results suggest that nicotinic receptors are found predominantly at presynaptic locations in the optic tectum while muscarinic receptors are most often present at postsynaptic sites. We conclude that both of these receptor types could substantially modulate visual activity by changing either the input to tectal neurons or the level of their response to that input.

MS lesion segmentation using a multi-channel patch-based approach with spatial consistency

NASA Astrophysics Data System (ADS)

Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit

2015-03-01

This paper presents an automatic method for segmentation of Multiple Sclerosis (MS) in Magnetic Resonance Images (MRI) of the brain. The approach is based on similarities between multi-channel patches (T1, T2 and FLAIR). An MS lesion patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally a novel iterative patch-based label refinement process based on the initial segmentation map is performed to ensure spatial consistency of the detected lesions. A leave-one-out evaluation is done for each testing image in the MS lesion segmentation challenge of MICCAI 2008. Results are shown to compete with the state-of-the-art methods on the MICCAI 2008 challenge.

Evaluation of modifications of the traditional patch test in assessing the chemical irritation potential of feminine hygiene products.

PubMed

Farage, Miranda A; Meyer, Sandy; Walter, Dave

2004-05-01

The first main objective of the work presented in this paper was to investigate ways of optimizing the current arm patch test protocol by (1) increasing the sensitivity of the test in order to evaluate more effectively the products that are inherently non-irritating, and/or (2) reducing the costs of these types of studies by shortening the protocol. The second main objective was to use the results of these studies and the results of the parallel studies conducted using the behind-the-knee method to better understand the contribution of mechanical irritation to the skin effects produced by these types of products. In addition, we were interested in continuing the evaluation of sensory effects and their relationship to objective measures of irritation. Test materials were prepared from three, currently marketed feminine protection pads. Wet and dry samples were applied to the upper arm using the standard 24-h patch test. Applications were repeated daily for 4 consecutive days. The test sites were scored for irritation prior to the first patch application, and 30-60 min after removal of each patch. Some test sites were treated by tape stripping the skin prior to the initial patch application. In addition, in one experiment, panelists were asked to keep a daily diary describing any sensory skin effects they noticed at each test site. All protocol variations ([intact skin/dry samples], [compromised skin/dry samples], [intact skin/wet samples], and [compromised skin/wet samples]) gave similar results for the products tested. When compared to the behind-the-knee test method, the standard upper arm patch test gave consistently lower levels of irritation when the test sites were scored shortly after patch removal, even though the sample application was longer (24 vs. 6 h) in the standard patch test. The higher level of irritation in the behind-the-knee method was likely due to mechanical irritation. The sensory skin effects did not appear to be related to a particular test product or a particular protocol variation. However, the mean irritation scores at those sites where a sensory effect was reported were higher than the mean irritation scores at those sites were no sensory effects were reported. All four protocol variations of the standard upper arm patch test can be used to assess the inherent chemical irritant properties of feminine protection products. For these products, which are inherently non-irritating, tape stripping and/or applying wet samples does not increase the sensitivity of the patch test method. Differences in irritation potential were apparent after one to three 24-h applications. Therefore, the standard patch test protocol can be shortened to three applications without compromising our ability to detect differences in the chemical irritation produced by the test materials. The patch test can be used to evaluate effectively the inherent chemical irritation potential of these types of products. However, this method is not suitable for testing the mechanical irritation due to friction that occurs during product use. There is no relationship between specific test conditions, i.e., compromised skin and/or testing wet samples and reports of perceived sensory reactions. However, there seems to be a clear relationship between sensory reactions and objective irritation scores.

Patch test responses to Malassezia pachydermatis in healthy basset hounds and in basset hounds with Malassezia dermatitis.

PubMed

Bond, R; Patterson-Kane, J C; Perrins, N; Lloyd, D H

2006-08-01

The effects of the patch test application of Malassezia pachydermatis extracts were evaluated in seven healthy basset hounds and in seven basset hounds with Malassezia dermatitis. Antigens (4 and 0.4 mg/ml) and saline controls were applied for 48 h using filter paper discs in Finn chambers. One healthy basset hound and five affected hounds showed positive patch test reactivity to the yeast antigens. Positive patch test reactions were characterized histologically by mild epidermal hyperplasia and mild to moderate perivascular, periadnexal and interstitial infiltrates of neutrophils and CD3+ lymphocytes. Immediate intradermal test reactivity to M. pachydermatis antigens was seen in one healthy and one affected hound, whereas delayed intradermal test reactivity was seen in six healthy hounds and five affected hounds. This study indicates that patch test reactivity to M. pachydermatis antigen may occur in healthy basset hounds, and in contrast to delayed intradermal test reactivity, is more frequent in basset hounds with Malassezia dermatitis.

Patch testing with thin-layer chromatograms of chamomile tea in patients allergic to sesquiterpene lactones.

PubMed

Lundh, Kerstin; Gruvberger, Birgitta; Möller, Halvor; Persson, Lena; Hindsén, Monica; Zimerson, Erik; Svensson, Ake; Bruze, Magnus

2007-10-01

Patients with contact allergy to sesquiterpene lactones (SLs) are usually hypersensitive to Asteraceae plant products such as herbal teas. The objective of this study was to show sensitizers in chamomile tea by patch testing with thin-layer chromatograms. Tea made from German chamomile was separated by thin-layer chromatography. Strips of the thin-layer chromatograms were used for patch testing SL-positive patients. 15 (43%) of 35 patients tested positively to 1 or more spots on the thin-layer chromatogram, with many individual reaction patterns. Patch testing with thin-layer chromatograms of German chamomile tea showed the presence of several allergens.

Recommendation to increase the test concentration of methylchloroisothiazolinone/methylisothiazolinone in the European baseline patch test series - on behalf of the European Society of Contact Dermatitis and the European Environmental and Contact Dermatitis Research Group.

PubMed

Bruze, Magnus; Goossens, An; Isaksson, Marléne

2014-07-01

Methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) in aqua is present in the European baseline patch test series at 100 ppm, whereas 200 ppm has been used in Sweden since 1986, in Spain in the late 1980s, and, in recent years, also in the United Kingdom and Ireland. With regard to MCI/MI, to investigate the data on contact allergy rates in dermatitis patients, the frequencies of allergic contact dermatitis in the same group, and adverse reactions, particularly patch test sensitization in tested dermatitis patients, and to find the optimal patch test concentration as dose in mg/cm(2) . We performed a survey of the literature found via the National Library of Medicine (PubMed, http://www.ncbi.nlm.nih.gov/pubmed, last accessed 20 February 2014). MCI/MI at 200 ppm aq. diagnosis substantially more contact allergy and allergic contact dermatitis, without any registered increase in patch test sensitization, than the presently used concentration of 100 ppm. MCI/MI at 200 ppm aq. is recommended to be included in the European baseline patch test series. To avoid patch test sensitization, a dose of 0.006 mg/cm(2) must not be exceeded, which means a volume of 15 µl for Finn Chambers(®) (Ø 8 mm). © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Concentrations and stability of methyl methacrylate, glutaraldehyde, formaldehyde and nickel sulfate in commercial patch test allergen preparations.

PubMed

Siegel, Paul D; Fowler, Joseph F; Law, Brandon F; Warshaw, Erin M; Taylor, James S

2014-05-01

Epicutaneous patch tests are used to reproduce allergy and diagnose allergic contact dermatitis. Reliable allergen test preparations are required. The purpose of the present study was to measure the actual concentrations of nickel(II) sulfate hexahydrate (NiSO4 ), methyl methacrylate, formaldehyde, and glutaraldehyde, and to compare them with the labelled concentrations, in commercial patch test allergen preparations found in dermatology clinics where patch testing is routinely performed. The commercial in-date and out-of-date patch test allergen preparations concentrations of NiSO4 , methyl methacrylate, formaldehyde and glutaraldehyde from one to three participating clinics were analysed with chromatographic or wet chemical techniques. NiSO4 and formaldehyde concentrations were at or above the labelled concentrations; however, formaldehyde loss occurred with storage. NiSO4 particulate was uniformly distributed throughout the petrolatum. 'In-use' methyl methacrylate reagent syringes all contained ≤ 56% of the 2% label concentration, with no observable relationship with expiration date. Lower methyl methacrylate cocentrations were consistently measured at the syringe tip end, suggesting loss resulting from methyl methacrylate's volatility. The concentrations of glutaraldehyde patch test allergen preparations ranged from 27% to 45% of the labelled (1% in pet.) concentration, independently of expiration date. Some false-negative methyl methacrylate, formaldehyde or glutaraldehyde patch test results may be attributable to instability of the test preparations. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Monitoring contact sensitization to p-phenylenediamine (PPD) by patch testing with PPD 0.3% in petrolatum.

PubMed

Geier, Johannes; Ballmer-Weber, Barbara K; Dickel, Heinrich; Frosch, Peter J; Bircher, Andreas; Weisshaar, Elke; Hillen, Uwe

2013-07-01

Being a contact allergen of general relevance, p-phenylenediamine (PPD) is patch tested in the baseline series. However, PPD 1% in petrolatum may actively sensitize. Patch testing with PPD at 0.35% pet. proved to be safe, as far as active sensitization is concerned. To determine whether PPD 0.3% pet. reliably detects PPD sensitization. Patch testing with PPD 0.3% pet. and 1% pet. synchronously was performed in consecutive patients in a multicentre study within the Information Network of Departments of Dermatology. Altogether, 2042 patients were patch tested. PPD 1% pet. yielded 6.0% positive reactions (n = 123), and PPD 0.3% pet. yielded 4.7% (n = 95). The synchronous reproducibility of PPD reactions was similar as known from parallel patch tests with identical PPD concentrations. The diagnostic properties of PPD 0.3% pet. expressed as reaction index and positivity ratio were good. Of the 123 patients reacting to PPD 1% pet., 32 (26%) had no positive reaction to PPD 0.3% pet. In 22 of these 32 patients (69%), no clinical relevance could be found. As patch testing with PPD 0.3% pet. is reliable according to our results, we recommend replacing PPD 1% pet. in the baseline series with PPD 0.3% pet. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Atopy patch tests in young adult patients with atopic dermatitis and controls: dose-response relationship, objective reading, reproducibility and clinical interpretation.

PubMed

Bygum, Anette; Mortz, Charlotte Gotthard; Andersen, Klaus Ejner

2003-01-01

The clinical interpretation and reproducibility of atopy patch tests was studied in 23 selected young adult patients with atopic dermatitis and 25 healthy controls using standard inhalant allergens. Non-invasive measurements were used for objective assessment of test reactions and the participants were retested after 6 weeks. Ten of 19 (53%) evaluable patients with atopic dermatitis had at least one positive atopy patch test. However, there was no clear clinical relevance of the atopy patch test results when related to patient history and distribution of dermatitis. Reproducible and dose-dependent results were obtained with Dermatophagoides pteronyssinus, grass and cat with a reproducibility rate of 0.69 to 0.81 in patients and 0.60-0.96 in controls. A unique finding was a significant positive correlation between a positive atopy patch test, allergen dose and increase in transepidermal water loss and erythema, while measurement of capacitance did not distinguish between positive and negative reactions. The results of the present study do not support the routine use of atopy patch tests in the evaluation of adult patients with atopic dermatitis.

Monitoring Pregnant Women’s Illicit Opiate and Cocaine Use With Sweat Testing

PubMed Central

Brunet, Bertrand R.; Barnes, Allan J.; Choo, Robin E.; Mura, Patrick; Jones, Hendrée E.; Huestis, Marilyn A.

2011-01-01

Dependence on illicit drugs during pregnancy is a major public health concern as there may be associated adverse maternal, fetal, and neonatal consequences. Sweat patches (n = 389) were collected from 39 pregnant volunteers who provided written informed consent for this Institutional Review Board-approved protocol and wore patches, replaced approximately weekly, from study entry until delivery. Patches were analyzed for opiates (heroin, 6-acetylmor-phine, 6-acetylcodeine, morphine and codeine) and cocaine (cocaine, benzoylecgonine, ecgonine methyl ester, anhydroecgonine methyl ester) by solid phase extraction and gas chromatography mass spectrometry. Seventy-one percent (276) of collected sweat patches were ≥5 ng per patch (limit of quantification) for one or more analytes. Cocaine was present in 254 (65.3%) patches in concentrations ranging from 5.2 to 11,835 ng per patch with 154 of these high enough to satisfy the proposed Substance Abuse and Mental Health Services Administration guidelines for a confirmatory drug test (25 ng per patch). Interestingly, 6-acetylmorphine was the most prominent opiate analyte documented in 134 patches (34.4%) with 11.3% exceeding the proposed opiate Substance Abuse and Mental Health Services Administration cut-off (25 ng per patch). Heroin was identified in fewer patches (77), but in a similar concentration range (5.3–345.4 ng per patch). Polydrug use was evident by the presence of both cocaine and opiate metabolites in 136 (35.0%) patches. Sweat testing is an effective method for monitoring abstinence or illicit drug use relapse in this high-risk population of pregnant opiate- and/or cocaine-dependent women. PMID:19927046

Validation of a novel epicutaneous delivery system for patch testing of house dust mite-hypersensitive dogs.

PubMed

Olivry, Thierry; Linder, Keith E; Paps, Judy S; Bizikova, Petra; Dunston, Stan; Donne, Nathalie; Mondoulet, Lucie

2012-12-01

Patch tests with allergens are used for the evaluation of cellular hypersensitivity to food and environmental allergens in dogs and humans with atopic dermatitis. Viaskin is a novel allergen epicutaneous delivery system that enhances epidermal allergen capture by immune cells. To compare the use of Viaskin and Finn chamber patch tests in dogs hypersensitive to mite allergens. Empty control or Dermatophagoides farinae house dust mite-containing Viaskin or Finn chamber patches were applied to the thoracic skin of six mite-hypersensitive Maltese-beagle crossbred atopic dogs. Lesions were graded 49 and 72 h after patch test application, and skin biopsies were collected after 72 h. Overall microscopic inflammation, eosinophil and T-lymphocyte infiltrations were scored. Positive macroscopic patch test reactions developed at five of six Viaskin application sites and four of six Finn chamber application sites. Median microscopic epidermal and dermal inflammation, as well as eosinophil and CD3 T-lymphocyte dermal scores were always higher in biopsies collected at Viaskin than at Finn chamber sites. Microscopic inflammation scores were significantly higher after mite allergen-containing Viaskin compared with empty patches, but this was not the case for mite-containing Finn chambers compared with control chambers. Scores obtained using Viaskin were not significantly different from those obtained using Finn chambers. Macroscopic and microscopic scores were significantly correlated. In mite-allergic dogs, Viaskin epicutaneous delivery systems appear to induce stronger allergen-specific inflammation than currently used Finn chamber patch tests. Consequently, Viaskin patches might offer a better alternative for screening cellular hypersensitivity to food and environmental allergens. © 2012 The Authors. Veterinary Dermatology © 2012 ESVD and ACVD.

FOOT ECZEMA: THE ROLE OF PATCH TEST IN DETERMINING THE CAUSATIVE AGENT USING STANDARD SERIES

PubMed Central

Priya, K S; Kamath, Ganesh; Martis, Jacintha; D, Sukumar; Shetty, Narendra J; Bhat, Ramesh M; Kishore, B Nanda

2008-01-01

Foot dermatitis refers to the predominant involvement of feet in the eczematous process. This study is undertaken to determine the clinical pattern and causative agent in foot eczema and to evaluate the role of patch testing in determining the causative agent of foot eczema. Data was collected from 50 patients with foot eczema, who attended the out-patient department. The patch test was performed using Indian standard series. Patch test was positive in 88% of the patients. The most common site affected was the dorsal aspect of the foot (48%) and scaly plaque was the predominant morphological pattern. The highest number of patients (24%) showed positive reactions to mercaptobenzothiazole (MBT) and the lowest (4%) to neomycin sulfate. Rubber and rubber chemicals have been reported worldwide to be the most common sensitizer causing foot eczema. Thus, patch test has a major role in finding out the cause of foot eczema. PMID:19881990

Allergy Skin Tests

MedlinePlus

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

Membrane Vibration Tests Using Surface-Bonded Piezoelectric Patch Actuation

NASA Technical Reports Server (NTRS)

Gasper, James L.; Pappa, Richard S.

2003-01-01

This paper describes the status of on-going work at the NASA Langley Research Center to measure the dynamics of thin membranes. The test article is a one-meter square pre-tensioned Kapton membrane that incorporates small surface-bonded piezoelectric patches strategically positioned to excite many modes. It is shown that PVDF (polyvinylidene fluoride) and MFC (macro fiber composite) piezoelectric patch actuators provide adequate excitation energy to obtain modal frequencies and mode shapes. Results from modal tests performed on the membrane using piezoelectric patches of different sizes and positions are discussed.

Contact urticaria, allergic contact dermatitis, and photoallergic contact dermatitis from oxybenzone.

PubMed

Landers, Maeran; Law, Sandra; Storrs, Frances J

2003-03-01

There is little literature regarding conventional patch tests and photopatch tests to oxybenzone resulting in both immediate- and delayed-type hypersensitivity reactions. A patient was patch-tested and photopatch-tested to various sunscreen chemicals. Both immediate- and delayed-type hypersensitivity reactions were observed with oxybenzone. The positive patch tests were also photoaccentuated. Oxybenzone, a common sunscreen allergen, can result in both contact urticaria and delayed-type hypersensitivity on both conventional patch testing and photopatch testing. Allergic contact dermatitis to sunscreen chemicals has traditionally included contact urticaria, allergic contact dermatitis, and photoallergic contact dermatitis. Due to the recognition of p-aminobenzoic acid (PABA) and its esters as sensitizers, the presence of benzophenones in "PABA-free" sunscreens has become more prevalent, especially in sunscreens with a sun protection factor (SPF) greater than 8. In our patient, immediate- and delayed-type hypersensitivity reactions were seen to oxybenzone (2-hydroxy-4-methoxybenzophenone, 2-benzoyl-5-methoxyphenol, benzophenone-3, Eusolex 4360, Escalol 567, EUSORB 228, Spectra-Sorb UV-9, Uvinul M-40) upon conventional patch testing and photopatch testing.

Patch testing and allergen-specific serum IgE and IgG antibodies in the diagnosis of canine adverse food reactions.

PubMed

Bethlehem, Simone; Bexley, Jennifer; Mueller, Ralf S

2012-02-15

Adverse food reaction (AFR) is a common differential diagnosis for pruritic dogs. The only way to diagnose AFR is an elimination diet of 6-8 weeks with a protein and a carbohydrate source not previously fed. In humans, patch testing has been shown to be a useful tool to diagnose food allergies. In veterinary medicine, serum food allergen-specific antibody testing is widely offered to identify suitable ingredients for such diets. The aim of this study was to determine sensitivity, specificity, negative and positive predictability of patch testing with and serum antibody testing for a variety of common food stuffs. Twenty-five allergic dogs underwent an elimination diet and individual rechallenge with selected food stuffs, food patch testing and serum testing for food-antigen specific IgE and IgG. Eleven clinically normal control dogs only were subjected to patch and serum testing. The sensitivity and specificity of the patch test were 96.7 and 89.0% respectively, negative and positive predictability were 99.3 and 63.0%. For IgE and IgG the sensitivity was 6.7 and 26.7%, specificity were 91.4 and 88.3%, the negative predictive values 80.7 and 83.7% and the positive predictive values were 15.4 and 34.8%. Based on these results, a positive reaction of a dog on these tests is not very helpful, but a negative result indicates that this antigen is tolerated well. We conclude that patch testing (and to a lesser degree serum testing) can be helpful in choosing ingredients for an elimination diet in a dog with suspected AFR. Copyright © 2012. Published by Elsevier B.V.

A method to visualize transdermal nickel permeation in mouse skin using a nickel allergy patch

PubMed Central

Sugiyama, Tomoko; Uo, Motohiro; Wada, Takahiro; Hongo, Toshio; Omagari, Daisuke; Komiyama, Kazuo; Oikawa, Masakazu; Kusama, Mikio; Mori, Yoshiyuki

2015-01-01

Metal patch test is often used in clinical settings when metal-induced contact dermatitis is suspected. However, the transdermal permeation behavior of metal ions from the patch test remains unclear. Current patch tests using high concentrations of metal salt solutions have some side effects, e.g. acute skin reactions to high concentrations of metal salt. To resolve these, estimating metal ion transdermal permeation is wished. In this study, synchrotron radiation X-ray fluorescence (SR-XRF) and micro-focused particle-induced X-ray emission (micro-PIXE) were used to visualize the time-dependent Ni permeation in mouse skin. The cross-sectional diffusion of Ni was visualized in a time-dependent manner. Our results indicate that maximum Ni permeation occurs after 24 h of patch treatment, and the permeated Ni content was high in the epidermis and spread into the dermis beyond the basal layer. This method may be useful to determine the appropriate solution concentration and duration of administration for the patch test. PMID:26484550

Patch testing custom isocyanate materials from the workplace.

PubMed

Burrows, Dianne; Houle, Marie-Claude; Holness, D Linn; DeKoven, Joel; Skotnicki, Sandy

2015-01-01

Patch testing with standard trays of commercially available allergens is the current practice for investigating suspected cases of isocyanate-induced allergic contact dermatitis (ACD). In some facilities, these standard trays are further supplemented with custom preparations of isocyanate-containing materials. The aim was to determine whether added value exists in patch testing patients to custom isocyanate preparations in suspected cases of ACD. We performed a retrospective analysis of 11 patients referred to our specialty clinic between January 2003 and March 2011 for suspected patients of ACD who had custom testing with isocyanate materials from their workplace. In addition to standard trays of allergens, all patients were patch tested with custom isocyanate materials from their workplaces. Three (27%) of 11 patients showed an added value in testing to custom isocyanate allergens. Of these 3 patients, one had a reaction that reinforced positive reactions to the standard isocyanate tray, but the other 2 (18%) had no reactions to any of the commercially available allergens. Because of the high proportion of reactions (27%), we recommend the use of custom testing to workplace isocyanate products as a supplement to current standard patch testing procedures.

Flow cytometric analysis of regulatory T cells during hyposensitization of acquired allergic contact dermatitis.

PubMed

Fraser, Kathleen; Abbas, Mariam; Hull, Peter R

2014-01-01

We previously demonstrated that repeated intradermal steroid injections administered at weekly intervals into positive patch-test sites induce hyposensitization and desensitization. To examine changes in CD4CD25CD127lo/ regulatory T cells during the attenuation of the patch-test response. Ten patients with known allergic contact dermatitis were patch tested weekly for 10 weeks. The patch-test site was injected intradermally with 2 mg triamcinolone. At weeks 1 and 7, a biopsy was performed on the patch-test site in 6 patients, and flow cytometry was performed assessing CD4CD25CD127lo/ regulatory T cells. Secondary outcomes were clinical score, reaction size, erythema, and temperature. Statistical analysis included regression, correlation, and repeated-measures analysis of variance. The percentage of CD4CD25CD127lo/ regulatory T cells, measured by flow cytometry, increased from week 1 to week 7 by an average of 19.2%. The average grade of patch-test reaction decreased from +++ (vesicular reaction) to ++ (palpable erythema). The mean drop in temperature following treatment was 0.28°C per week. The mean area decreased 8.6 mm/wk over 10 weeks. Intradermal steroid injections of weekly patch-test reactions resulted in hyposensitization of the allergic contact dermatitis reaction. CD4CD25CD127lo/ regulatory T cells showed a tendency to increase; however, further studies are needed to determine if this is significant.

Effects of time and recall of patch test results on quality of life (QoL) after testing. Cross-sectional study analyzing QoL in hand eczema patients 1, 5 and 10 years after patch testing.

PubMed

Jamil, Wasim N; Lindberg, Magnus

2017-08-01

Patch testing can improve health-related quality of life (HRQOL). To study the impact on HRQOL of elapsed time after patch testing (1-10 years), and how the outcome of testing and patients' recall affects HRQOL. The Dermatology Life Quality Index (DLQI) questionnaire was sent to all patients (aged 18-65 years) who were patch tested for suspected contact allergy in 2009, 2005 and 2000 at the Department of Dermatology in Örebro. The response rate was 51% (n = 256). The DLQI score was significantly lower at 10 years after patch testing (mean DLQI = 5.5) than at 1 year (mean DLQI = 7.7). Work was the most impaired aspect. A binary logistic model showed that only time (10 years after testing) was associated with no effect, a light effect or a moderate effect (DLQI < 10) on HRQOL. No such association was seen for patients with negative or positive test results concerning full recall, partial recall or no recall of diagnosed allergens. Although there was an improvement in HRQOL over time, the work aspect remained a major problem. The improvement was not affected by the outcome of testing and patients' recall of test results. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Preferences among four combination nicotine treatments.

PubMed

Schneider, Nina G; Koury, Margaret A; Cortner, Chris; Olmstead, Richard E; Hartman, Neil; Kleinman, Leonard; Kim, Andrew; Chaya, Craig; Leaf, David

2006-09-01

Acute nicotine replacement treatments (NRTs) are disliked or misused, leading to insufficient nicotine intake and poor outcome. Patches provide steady nicotine but are slow and passive. Combining systems may improve efficacy with acute NRTs tailored for compliance. To test initial reactions to and use preferences among combinations of NRTs. Smokers (n=27) tested four combination NRTs in a 5-day crossover trial: 2/4-mg gum + 15-mg patch (G/P), 2/4-mg lozenges + 15-mg patch (L/P), inhaler + 15-mg patch (I/P), and 10 mg + 15-mg patches (P/P). Subjects rated an NRT combination each day after 5-6 h of use and ranked among the NRTs after testing all treatments. Double-patches (P/P) were ranked highest for "ease of use", "safety", and "use in public". However, for "help to quit", 70% preferred some form of acute-patch combination (A/P) compared to 30% choosing P/P. For "use under stress" (an immediate need), 93% preferred A/P systems compared to 7% choosing P/P. L/P ranked lowest for "ease of use", I/P and L/P were lowest on "safety", and I/P ranked lowest for "use in public". Expectations of NRTs changed with test experience for patches (better) and lozenges (worse). In brief testing, all combinations were acceptable. P/P was favored for ease, safety, and public use, but a majority chose A/P systems for help in quitting and use under stress. Combined use is viable and needs to be made known and accessible to smokers.

Pharmacokinetic Evaluation of Two Nicotine Patches in Smokers.

PubMed

Rasmussen, Scott; Horkan, Kathleen Halabuk; Kotler, Mitchell

2018-02-02

Smoking continues to be a major preventable cause of early mortality worldwide, and nicotine replacement therapy has been demonstrated to increase rates of abstinence among smokers attempting to quit. Nicotine transdermal systems (also known as nicotine patches) attach to the skin via an adhesive layer composed of a mixture of different-molecular-weight polyisobutylenes (PIBs) in a specific ratio. This randomized, single-dose, 2-treatment, crossover pharmacokinetic (PK) trial assessed the bioequivalence of nicotine patches including a replacement PIB adhesive (test) compared with the PIB adhesive historically used on marketed patches (reference). The test and reference patches were bioequivalent, as determined by the PK parameters of C max and AUC 0-t . In addition, the parameters T max and t 1/2 did not significantly differ between the 2 patches, supporting the bioequivalence finding from the primary analysis. The tolerability profiles of the patches containing the replacement and previously used PIB adhesives were similar; application-site adverse events did not significantly differ between test and reference patches. Overall, these data establish the bioequivalence of the nicotine patch with the replacement PIB adhesive formulation and the previously utilized PIB adhesive formulation. © 2018 The Authors. Clinical Pharmacology in Drug Development published by Wiley Periodicals, Inc. on behalf of The American College of Clinical Pharmacology.

Patch-augmented rotator cuff repair: influence of the patch fixation technique on primary biomechanical stability.

PubMed

Jung, Christian; Spreiter, Gregor; Audigé, Laurent; Ferguson, Stephen J; Flury, Matthias

2016-05-01

There is an ongoing debate about the potential of patch augmentation to improve biomechanical stability and healing associated with rotator cuff repair. The biomechanical properties of three different patch-augmented rotator cuff repair techniques were assessed in vitro and compared with a standard repair. Dermal collagen patch augmentation may increase the primary stability and strength of the repaired tendon in vitro, depending on the technique used for patch application. Forty cadaveric sheep shoulders with dissected infraspinatus tendons were randomized into four groups (n = 10/group) for tendon repair using a knotless double-row suture anchor technique. A xenologous dermal extracellular matrix patch was used for augmentation in the three test groups using an "integrated", "cover", or "hybrid" technique. Tendons were preconditioned, cyclically loaded from 10 to 30 N at 1 Hz, and then loaded monotonically to failure. Biomechanical properties and the mode of failure were evaluated. Patch augmentation significantly increased the maximum load at failure by 61 % in the "cover" technique test group (225.8 N) and 51 % in the "hybrid" technique test group (211.4 N) compared with the non-augmented control group (140.2 N) (P ≤ 0.015). For the test group with "integrated" patch augmentation, the load at failure was 28 % lower (101.6 N) compared with the control group (P = 0.043). There was no significant difference in initial and linear stiffness among the four experimental groups. The most common mode of failure was tendon pullout. No anchor dislocation, patch disruption or knot breakage was observed. Additional patch augmentation with a collagen patch influences the biomechanical properties of a rotator cuff repair in a cadaveric sheep model. Primary repair stability can be significantly improved depending on the augmentation technique.

Cutaneous hypersensitivity reactions to freshwater cyanobacteria – human volunteer studies

PubMed Central

Stewart, Ian; Robertson, Ivan M; Webb, Penelope M; Schluter, Philip J; Shaw, Glen R

2006-01-01

Background Pruritic skin rashes associated with exposure to freshwater cyanobacteria are infrequently reported in the medical and scientific literature, mostly as anecdotal and case reports. Diagnostic dermatological investigations in humans are also infrequently described. We sought to conduct a pilot volunteer study to explore the potential for cyanobacteria to elicit hypersensitivity reactions. Methods A consecutive series of adult patients presenting for diagnostic skin patch testing at a hospital outpatient clinic were invited to participate. A convenience sample of volunteers matched for age and sex was also enrolled. Patches containing aqueous suspensions of various cyanobacteria at three concentrations were applied for 48 hours; dermatological assessment was made 48 hours and 96 hours after application. Results 20 outpatients and 19 reference subjects were recruited into the study. A single outpatient produced unequivocal reactions to several cyanobacteria suspensions; this subject was also the only one of the outpatient group with a diagnosis of atopic dermatitis. No subjects in the reference group developed clinically detectable skin reactions to cyanobacteria. Conclusion This preliminary clinical study demonstrates that hypersensitivity reactions to cyanobacteria appear to be infrequent in both the general and dermatological outpatient populations. As cyanobacteria are widely distributed in aquatic environments, a better appreciation of risk factors, particularly with respect to allergic predisposition, may help to refine health advice given to people engaging in recreational activities where nuisance cyanobacteria are a problem. PMID:16584576

Allergic contact dermatitis caused by isobornyl acrylate in OmniPod, an innovative tubeless insulin pump.

PubMed

Raison-Peyron, Nadia; Mowitz, Martin; Bonardel, Nathalie; Aerts, Olivier; Bruze, Magnus

2018-04-10

The frequency of allergic contact dermatitis caused by (meth)acrylates is increasing worldwide, and isobornyl acrylate (IBOA) has been identified as a culprit sensitizer in FreeStyle Libre, a medical device used by diabetic patients. To report on 4 patients sensitized to IBOA contained in OmniPod, a new, tubeless insulin pump, and to describe the clinical and chemical analytical work-up. Four patients with eczematous skin eruptions after using OmniPod, including 2 with previous adverse skin reactions to FreeStyle Libre, were patch tested with a baseline series and additional (meth)acrylates, including IBOA in several concentrations and/or vehicles. Gas chromatography-mass spectrometry (GC-MS) was used to identify the presence of IBOA in OmniPod. All patients were shown to be sensitized to IBOA. GC-MS identified IBOA in OmniPod, with the highest concentrations being found in the unit itself and not in the adhesive patch. The OmniPod tubeless insulin pump is another source of IBOA, and its use may lead to primary sensitization to this acrylate, or may provoke elicitation of allergic contact dermatitis in previously sensitized patients. Our cases highlight the need to obtain satisfactory cooperation from pharmaceutical companies involved in the manufacture of these widely used medical devices. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The prevalence of positive reactions in the atopy patch test with aeroallergens and food allergens in subjects with atopic eczema: a European multicenter study.

PubMed

Darsow, U; Laifaoui, J; Kerschenlohr, K; Wollenberg, A; Przybilla, B; Wüthrich, B; Borelli, S; Giusti, F; Seidenari, S; Drzimalla, K; Simon, D; Disch, R; Borelli, S; Devillers, A C A; Oranje, A P; De Raeve, L; Hachem, J-P; Dangoisse, C; Blondeel, A; Song, M; Breuer, K; Wulf, A; Werfel, T; Roul, S; Taieb, A; Bolhaar, S; Bruijnzeel-Koomen, C; Brönnimann, M; Braathen, L R; Didierlaurent, A; André, C; Ring, J

2004-12-01

The atopy patch test (APT) was proposed to evaluate IgE-mediated sensitizations in patients with atopic eczema (AE). The prevalence and agreement with clinical history and specific IgE (sIgE) of positive APT reactions was investigated in six European countries using a standardized method. A total of 314 patients with AE in remission were tested in 12 study centers on clinically uninvolved, non-abraded back skin with 200 index of reactivity (IR)/g of house dust mite Dermatophagoides pteronyssinus, cat dander, grass, and birch pollen allergen extracts with defined major allergen contents in petrolatum. Extracts of egg white, celery and wheat flour with defined protein content were also patch tested. APT values were evaluated at 24, 48, and 72 h according to the European Task Force on Atopic Dermatitis (ETFAD) guidelines. In addition, skin-prick test (SPT) and sIgE and a detailed history on allergen-induced eczema flares were obtained. Previous eczema flares, after contact with specific allergens, were reported in 1% (celery) to 34% (D. pteronyssinus) of patients. The frequency of clear-cut positive APT reactions ranged from 39% with D. pteronyssinus to 9% with celery. All ETFAD intensities occured after 48 and 72 h. Positive SPT (16-57%) and elevated sIgE (19-59%) results were more frequent. Clear-cut positive APT with all SPT and sIgE testing negative was seen in 7% of the patients, whereas a positive APT without SPT or sIgE for the respective allergen was seen in 17% of the patients. APT, SPT and sIgE results showed significant agreement with history for grass pollen and egg white (two-sided Pr > /Z/ < or = 0.01). In addition, SPT and sIgE showed significant agreement with history for the other aeroallergens. With regard to clinical history, the APT had a higher specificity (64-91% depending on the allergen) than SPT (50-85%) or sIgE (52-85%). Positive APT were associated with longer duration of eczema flares and showed regional differences. In 10 non-atopic controls, no positive APT reaction was seen. Aeroallergens and food allergens are able to elicit eczematous skin reactions after epicutaneous application. As no gold standard for aeroallergen provocation in AE exists, the relevance of aeroallergens for AE flares may be evaluated by APT in addition to SPT and sIgE. The data may contribute to the international standardization of the APT.

Surface gloss and color perception of 3D objects.

PubMed

Xiao, Bei; Brainard, David H

2008-01-01

Two experiments explore the color perception of objects in complex scenes. The first experiment examines the color perception of objects across variation in surface gloss. Observers adjusted the color appearance of a matte sphere to match that of a test sphere. Across conditions we varied the body color and glossiness of the test sphere. The data indicate that observers do not simply match the average light reflected from the test. Indeed, the visual system compensates for the physical effect of varying the gloss, so that appearance is stabilized relative to what is predicted by the spatial average. The second experiment examines how people perceive color across locations on an object. We replaced the test sphere with a soccer ball that had one of its hexagonal faces colored. Observers were asked to adjust the match sphere have the same color appearance as this test patch. The test patch could be located at either an upper or lower location on the soccer ball. In addition, we varied the surface gloss of the entire soccer ball (including the test patch). The data show that there is an effect of test patch location on observers' color matching, but this effect is small compared to the physical change in the average light reflected from the test patch across the two locations. In addition, the effect of glossy highlights on the color appearance of the test patch was consistent with the results from Experiment 1.

Surface gloss and color perception of 3D objects

PubMed Central

Xiao, Bei; Brainard, David H.

2008-01-01

Two experiments explore the color perception of objects in complex scenes. The first experiment examines the color perception of objects across variation in surface gloss. Observers adjusted the color appearance of a matte sphere to match that of a test sphere. Across conditions we varied the body color and glossiness of the test sphere. The data indicate that observers do not simply match the average light reflected from the test. Indeed, the visual system compensates for the physical effect of varying the gloss, so that appearance is stabilized relative to what is predicted by the spatial average. The second experiment examines how people perceive color across locations on an object. We replaced the test sphere with a soccer ball that had one of its hexagonal faces colored. Observers were asked to adjust the match sphere have the same color appearance as this test patch. The test patch could be located at either an upper or lower location on the soccer ball. In addition, we varied the surface gloss of the entire soccer ball (including the test patch). The data show that there is an effect of test patch location on observers’ color matching, but this effect is small compared to the physical change in the average light reflected from the test patch across the two locations. In addition, the effect of glossy highlights on the color appearance of the test patch was consistent with the results from Experiment 1. PMID:18598406

Results of tests of K5NA and a revised formulation of EPDM/cork patch material in MSFC Hot Gas Facility

NASA Technical Reports Server (NTRS)

Dean, W. G.

1982-01-01

During prelaunch procedures at Kennedy Space Center some of the EPDM Thermal Protection System material was damaged on the Solid Rocket Booster stiffener stubs. The preferred solution was to patch the damaged areas with a cork-filled epoxy patching compound. Before this was done, however, it was requested that this patching technique be checked out by testing it in the MSFC Hot Gas Facility. Two tests were run in the HFG in 1980. The results showed the patch material to be adequate. Since that time, the formulation of the cork-filled epoxy material has been changed. It became necessary to retest this concept to be sure that the new material is as good as or better than the original material. In addition to the revised formulation material, tests were also made using K5NA as the patch material. The objectives of the tests reported herein were to: (1) compare the thermal performance of the original and the new cork-filled epoxy formulations, and (2) compare the K5NA closeout material to these epoxy materials. Material specifications are also discussed.

A patch test confirmed phenobarbital-induced fixed drug eruption in a child.

PubMed

Chadly, Zohra; Aouam, Karim; Chaabane, Amel; Belhadjali, Hichem; Abderrazzak Boughattas, Naceur; Zili, Jamel Eddine

2014-06-01

A-10-year-old girl was referred to our department for multiple hyperpigmented plaques. One week previously, she had been given one suppository of acetylsalicylic acid - phenobarbital for fever. Twelve hours after the drug intake the child developed pruritic red plaques on the left thigh. Six weeks after resolution of the acute reaction, patch tests were performed separately, with phenobarbital and acetylsalicylic acid. On 48-hour reading, only the phenobarbital patch test on residual pigmented lesion was positive. Because of possible cross-reactions between aromatic anticonvulsants, subsequent patch tests using carbamazepine and phenytoin on residual pigmented lesions were performed. They were all negative at 48-hour reading. To our knowledge, only two isolated pediatric cases of Phenobarbital-induced FDE have been reported in the literature. In this case report, as it was difficult to determine whether phenobarbital or acetylsalicylic acid was responsible for this reaction, subsequent patch tests allowed the identification of the culprit component since it was positive to phenobarbital.

Patch Testing in Patients with Suspected Footwear Dermatitis: A Retrospective Study.

PubMed

Garg, Taru; Agarwal, Soumya; Rana, Shiwangi; Chander, Ram

2017-01-01

Footwear dermatitis represents a common but often undiagnosed or misdiagnosed condition. Patch testing aids in its confirmation and identification of the offending allergen. This study aimed to find the frequency of positive patch test reactions in cases with suspected allergic contact dermatitis (ACD) to footwear, as well as the common responsible allergens. This is a retrospective record based study of 37 patients, with suspected ACD to footwear, who underwent patch testing with Indian standard series and Indian footwear series from July 2012 to July 2015. The majority of patients (45.94%) belonged to the age group of 20-40 years. Dorsal aspects of feet (81.08%) and soles (18.92%) were the common sites involved. Patch test was positive in 18.92% patients. The most common causative allergens were hydroquinone monobenzylether (8.11%) and 4-aminoazobenzene (5.41%). Common chemicals implicated in ACD were rubber, rubber additives, and dyes. The principal culprit allergens were hydroquinone monobenzylether and 4-aminoazobenzene.

2-Amino-4-hydroxyethylaminoanisole sulfate - a coupler causing contact allergy from use in hair dyes.

PubMed

Madsen, Jakob T; Andersen, Klaus E

2016-02-01

Allergic contact dermatitis resulting from the use of permanent hair dyes is common. Approximately 100 hair dye chemicals are permitted in Europe. Hair dye ingredients may change over time, and hence new hair dye allergens should be looked for continuously. To review positive patch test reactions to the coupler 2-amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014. Patch test results from the Allergen Bank database for eczema patients patch tested with 2-amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014 were reviewed. A total of 902 dermatitis patients (154 from the dermatology department and 748 from 65 practices) were patch tested with amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014. Thirteen (1.4%) patients had a positive patch test reaction. Our results do not indicate irritant reactions. 2-Amino-4-hydroxyethylaminoanisole sulfate is a new but rare contact allergen. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Patch test reactivity to metal allergens following regulatory interventions: a 33-year retrospective study.

PubMed

Thyssen, Jacob Pontoppidan; Ross-Hansen, Katrine; Menné, Torkil; Johansen, Jeanne Duus

2010-08-01

Contact allergy epidemics to chromate and nickel were addressed in Denmark in 1983 and 1990 by regulatory interventions. To evaluate whether regulatory interventions on nickel and chromate exposure have reduced the proportion of strong patch test reactions. 22 506 patients with dermatitis aged 4-99 years were patch tested with nickel sulfate, potassium dichromate, or cobalt chloride between 1977 and 2009. The proportion of 3+ reactions to nickel sulfate was reduced and almost disappeared after the mid- and late 1980s (P-trend = 0.001). Today, 1+ and 2+ nickel reactions occur equally frequent. Cobalt chloride patch test reactivity reflected the nickel development to some degree. The proportion of 3+ reactions to potassium dichromate was reduced during the 1980s (P-trend = 0.13), whereas the proportion of 2+ reactions to potassium dichromate have increased in recent years. The decrease in nickel sulfate and cobalt chloride 3+ patch test reactivity began long before the Danish nickel regulation came into effect. This could be because of research activity at the time as well as political attention in Northern Europe. The chromate content in cement regulation may have changed the epidemiology of patch test reactivity; however, in recent years, 2+ reactions to chromate have increased markedly, a development that should be carefully followed.

Investigation of contact allergy to dental materials by patch testing.

PubMed

Rai, Reena; Dinakar, Devina; Kurian, Swetha S; Bindoo, Y A

2014-07-01

Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG). Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials.

Patch test results with patients' own perfumes, deodorants and shaving lotions: results of the IVDK 1998-2002.

PubMed

Uter, W; Geier, J; Schnuch, A; Frosch, P J

2007-03-01

Assessment of the value of patch testing patients' own perfumes, eau de toilette, deodorants and shaving lotions with regard to diagnosing contact allergy to fragrances, and an analysis of the spectrum of concurrent patch test reactions to single fragrance allergens. Data of the Information Network of Departments of Dermatology (IVDK; http://www.ivdk.org) regarding patch test results with above products brought in by the patient, considered as possible cause of contact dermatitis, were retrospectively analysed. Between 1998 and 2002, 1468 patients were patch tested with 2557 single products (deodorants, n = 1094; eau de toilette, n = 598; perfume, n = 530; and pre- or after-shave, n = 325; remainder not classifiable), mostly 'as is'. Positive reactions were observed in 129 patients (to 191 products). In 58 of these patients, no further patch test reactions to the fragrance mix (FM-I), Myroxylon pereirae resin (balsam of Peru) or 4-(4-hydroxy-4-methyl-pentyl)-3-cyclohexencarboxaldehyde (e.g. Lyral(R)) were found. A strong association between contact sensitivity to the above commercial allergens and positive reactions to products was observed. Some single compounds such as ylang-ylang oil, propolis and especially oak moss absolute are important allergens in the 'perfume-positive' subgroup, but less in a subgroup positive to own deodorants. Patch testing this scope of products, brought in by the patient, can be regarded as a simple, safe and effective method to diagnose clinically relevant contact sensitization - the more so, as the composition of such products is ever-changing, and the sensitivity of established 'screening allergens' is thus insufficient.

Long-term healing of mildly cross-linked decellularized bovine pericardial aortic patch.

PubMed

Umashankar, P R; Sabareeswaran, A; Shenoy, Sachin J

2017-10-01

Glutaraldehyde treated bovine pericardium is extensively used in cardiovascular surgery. However, frequent occurrence of failure modes, such as calcification and structural failure, has hard pressed the need for finding an alternate technology. Decellularized bovine pericardium is an emerging technology. Mildly cross-linked decellularized bovine pericardium promotes positive remodeling with insignificant calcification and acute inflammation. In the present study, mildly cross-linked decellularized bovine pericardium was evaluated as a cardiovascular patch by studying mechanical strength as well as graft remodeling, resistance to calcific degeneration and inflammatory response using long duration porcine aortic implantation. It was observed that decellularized bovine pericardium, although thinner and less elastic had equivalent tensile properties such as tensile strength and stiffness when compared to commercially available glutaraldehyde-treated bovine pericardium. It showed the potential for site appropriate remodeling evidenced by host cell incorporation, thinner neointima, graft degradation, and neocollagenisation making it suitable for vascular patch application, whereas glutaraldehyde-treated pericardium failed to integrate with host tissue through timely degradation and host cell incorporation or neocollagenization. Conversely, it elicited persistent acute inflammation and produced calcification. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2145-2152, 2017. © 2016 Wiley Periodicals, Inc.

Taro corms mucilage/HPMC based transdermal patch: an efficient device for delivery of diltiazem hydrochloride.

PubMed

Sarkar, Gunjan; Saha, Nayan Ranjan; Roy, Indranil; Bhattacharyya, Amartya; Bose, Madhura; Mishra, Roshnara; Rana, Dipak; Bhattacharjee, Debashis; Chattopadhyay, Dipankar

2014-05-01

The aim of this work is to examine the effectiveness of mucilage/hydroxypropylmethylcellulose (HPMC) based transdermal patch (matrix type) as a drug delivery device. We have successfully extracted mucilage from Colocasia esculenta (Taro) corms and prepared diltiazem hydrochloride incorporated mucilage/HPMC based transdermal patches using various wt% of mucilage by the solvent evaporation technique. Characterization of both mucilage and transdermal patches has been done by several techniques such as Molisch's test, organoleptic evaluation of mucilage, mechanical, morphological and thermal analysis of transdermal patches. Skin irritation test is studied on hairless Albino rat skin showing that transdermal patches are apparently free of potentially hazardous skin irritation. Fourier transform infrared analysis shows that there is no interaction between drug, mucilage and HPMC while scanning electron microscopy shows the surface morphology of transdermal patches. In vitro drug release time of mucilage-HPMC based transdermal patches is prolonged with increasing mucilage concentration in the formulation. Copyright © 2014 Elsevier B.V. All rights reserved.

Finding the optimal patch test material and test concentration to detect contact allergy to geraniol.

PubMed

Hagvall, Lina; Karlberg, Ann-Therese; Christensson, Johanna B

2013-04-01

Geraniol is a commonly used fragrance terpene, and is tested in the baseline series in fragrance mix I. Geraniol is a pro-hapten and a pre-hapten, and sensitizers are formed in the autoxidation and skin metabolism of geraniol. Previous patch testing with air-exposed (oxidized) geraniol has suggested that oxidized geraniol could be a better marker for contact allergy to geraniol than pure geraniol. To find the optimal patch test substance and concentration for detecting contact allergy to geraniol. Six hundred and fifty-five patients were patch tested with pure and oxidized geraniol at 4.0%, 6.0% and 11.0% in petrolatum. Before patch testing, the irritant properties of pure and oxidized geraniol were studied in 27 patients at 2.5%, 5.0%, 10.0% and 20.0% pet. Pure geraniol detected positive reactions in 0.15-1.1% of the patients, and oxidized geraniol detected positive reactions in 0.92-4.6% of the patients. Reactions to pure geraniol in patients not reacting to oxidized geraniol indicated metabolic activation of geraniol. Neither pure nor oxidized geraniol gave significant irritant reactions. Increasing the test concentrations of pure and oxidized geraniol enables the detection of more cases of contact allergy. Oxidized geraniol detects more patients than pure geraniol, but patch testing with only oxidized geraniol does not detect all cases of contact allergy to geraniol. © 2013 John Wiley & Sons A/S.

Patch test standard series recommended by the Brazilian Contact Dermatitis Study Group during the 2006-2011 period.

PubMed

Duarte, Ida Alzira Gomes; Tanaka, Greta Merie; Suzuki, Nathalie Mie; Lazzarini, Rosana; Lopes, Andressa Sato de Aquino; Volpini, Beatrice Mussio Fornazier; Castro, Paulo Carrara de

2013-01-01

A retrospective study was carried out between 2006-2011. Six hundred and eighteen patients with suspected allergic contact dermatitis underwent the standard patch test series recommended by the Brazilian Contact Dermatitis Research Group. The aim of our study was to evaluate the variation of positive patch-test results from standard series year by year. The most frequently positive allergens were: nickel sulfate, thimerosal and potassium bichromate. Decrease of positive patch-test results over the years was statistically significant for: lanolin (p=0.01), neomycin (p=0.01) and anthraquinone (p=0.04). A follow-up study should be useful in determining which allergens could be excluded from standard series, as they may represent low sensitization risk.

Utility of patch testing for patients with drug eruption.

PubMed

Ohtoshi, S; Kitami, Y; Sueki, H; Nakada, T

2014-04-01

Patch testing is less dangerous than oral provocation testing for identification of the causative drug for patients with drug eruption; however, its usefulness for such identification is controversial. To clarify the rates of positive patch testing for patients with drug eruption, classified by causative drugs and clinical features. We analysed results during the period 1990-2010 for 444 patients (151 men, 293 women; mean ± SD age 49.9 ± 18.6 years) who were tested for drug eruption. In the patient group, there were 309 people (69.1%) with maculopapular eruption and 31 (6.9%) with severe drug eruption. The test materials were applied to the back and left for 2 days under occlusion, then results were assessed by the International Contact Dermatitis Research Group (ICDRG) scoring system 3 days after application. Reactions of + to +++ were regarded as positive. Of the 444 patients, 100 (22.4%) had a positive patch test result to a suspected drug. Positive rates were 23.6% and 20.0% for maculopapular eruption and fixed drug eruption, respectively. The class of materials to which most patients reacted positively was contrast medium (n = 53; 41.1%), followed by drugs acting on the central nervous system (n = 18; 28.6%). In the latter group, 16 of the 18 patients were positive to antiepileptics. Positive rates depend on the causative drug rather than the clinical features of the drug eruption. Patch testing is useful when contrast medium or antiepileptics are suspected to be the causative drugs. However, standardization of patch test materials and method of reading is needed, as well as guidelines regarding when testing should be performed. Although patch testing for drug eruption has significant potential, it requires further validation. © 2014 The Authors. Clinical and Experimental Dermatology published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists.

Randomized, double-blind, placebo-controlled trial using lidocaine patch 5% in traumatic rib fractures.

PubMed

Ingalls, Nichole K; Horton, Zachary A; Bettendorf, Matthew; Frye, Ira; Rodriguez, Carlos

2010-02-01

The lidocaine patch 5% was developed to treat postherpetic neuralgia. Anecdotal experience at our institution suggests the lidocaine patch 5% decreases narcotic usage in patients with traumatic rib fractures. This trial was developed to define the patch's efficacy. Patients with rib fractures admitted to the trauma service at our Level I trauma center were enrolled and randomized in a 1 to 1 double-blind manner to receive a lidocaine patch 5% or placebo patch. Fifty-eight patients who met the inclusion criteria were enrolled from January 2007 to August 2008. Demographic and clinical information were recorded. The primary outcomes variable was total narcotic use, analyzed using the 1-tailed Mann-Whitney test. The secondary outcomes variables included non-narcotic pain medication, average pain score, pulmonary complications, and length of stay. Significance was defined based on a 1-sided test for the primary outcome and 2-sided tests for other comparisons, at p < 0.05. Thirty-three patients received the lidocaine patch 5% and 25 received the placebo patch. There were no significant differences in age, number of rib fractures, gender, trauma mechanism, preinjury lung disease, smoking history, percent of current smokers, and need for placement of chest tube between the lidocaine patch 5% and placebo groups. There was no difference between the lidocaine patch 5% and placebo groups, respectively, with regard to total IV narcotic usage: median, 0.23 units versus 0.26 units; total oral narcotics: median, 4 units versus 7 units; pain score: 5.6 +/- 0.4 versus 6.0 +/- 0.3 (mean +/- SEM); length of stay: 7.8 +/- 1.1 versus 6.2 +/- 0.7; or percentage of patients with pulmonary complications: 72.7% versus 72.0%. The lidocaine patch 5% does not significantly improve pain control in polytrauma patients with traumatic rib fractures.

Biocompatibility tests of components of an implantable cardiac assist device.

PubMed

von Recum, A F; Imamura, H; Freed, P S; Kantrowitz, A; Chen, S T; Ekstrom, M E; Baechler, C A; Barnhart, M I

1978-09-01

A permanently implantable in-series left ventricular assist device, the dynamic aortic patch (DAP), has been tested in chronic animal experiments. The DAP replaces a section of the intrathoracic aortic wall. Hemothorax and hematocele at the implantation site have been complications in recent experiments. Primary postoperative hemorrhage was ruled out, and the biocompatibility of all components was therefore examined. Dacron velour, Teflon felt, conductive polyurethane, segmented polyether polyurethane, and Teflon-coated polyester fiber sutures were implanted in the pleural cavities of dogs and tested in vitro by culturing canine saphenous vein explants on them. In vivo experiments demonstrated that all components elicited mild to moderate inflammatory reactions, but hematocele occurred only when the components were implanted in the aorta with direct blood contact and exposed to arterial blood pressures. In vitro, cells were cultured on all components with no signs of toxic reactions. These results indicated that the host tolerated all implant components without major inflammatory responses. However, histological data indicated that chronic slow bleeding into or through the Dacron velour in contact with the arterial blood serum could account for hemothorax or hematocele formation. Therefore, a configuration of the assist device using materials impermeable to blood may obviate these difficulties.

Assessment of Irritation and Sensitization Potential of Eight Baby Skin Care Products.

PubMed

Galzote, Carlos; Thomas, Mini; Sachdev, Mukta

2016-10-01

Ethnic differences in skin sensitivity suggest that greater emphasis be focused on understanding a product's effect in diverse populations. The irritation and/or sensitization potential of 8 baby skin care products in Indian adults were evaluated using cumulative irritation tests (CIT) and human repeat insult patch testing (HRIPT) protocols. Healthy males or females aged 18 to 65 years of Indian ethnicity were treated with each of 6 products (cream, hair oil, lotion, body wash, shampoo, and baby soap) using CIT (n = 25) and HRIPT (n = 200). Baby powder and baby oil were evaluated by CIT (n = 25) and HRIPT (n = 107) in separate studies. CITs were conducted over 14 days; HRIPTs were conducted over 10 weeks. In both CIT and HRIPT, most products were considered mild, with no irritation. Baby soap and powder elicited reactions in the HRIPT induction phase, with positive challenge phase reactions (3 subjects), but were affirmed to be nonallergenic in the rechallenge phase. In these studies, 8 baby skin care products were evaluated by both CIT and HRIPT in Indian adults. The results of the studies indicated that all of the tested products were nonallergenic and nonirritating.

J Drugs Dermatol. 2016;15(10):1244-1248.

Clinical update on contact allergy.

PubMed

Uter, Wolfgang; Johansen, Jeanne Duus; Orton, David I; Frosch, Peter J; Schnuch, Axel

2005-10-01

The aim of this article is to review recent findings in contact allergy, regarding clinical research. The biocide methyldibromo glutaronitrile was identified to be an important sensitizer. Subsequently, it was banned from leave-on cosmetics in the European Union. Another group of important allergens that have been studied extensively included the fragrances oak moss absolute, isoeugenol, hydroxyisohexyl 3-cyclohexene carboxaldehyde and farnesol. A new fragrance mix II has been developed for standard testing, which includes the two latter compounds. Dose response studies have demonstrated broad individual variation of elicitation thresholds, dependent on the allergen concentration during induction, and other factors. Some unsuspected routes of exposure to allergens include oral, inhalational, connubial or airborne contact. Experimental studies provide a classification of newly introduced chemicals; increasingly, the local lymph node assay is supplementing and potentially replacing the guinea pig maximization test. Recent advances in occupational contact allergy include, for example, some attempts to improve diagnostics for epoxy resin and other plastic, glue, and cutting fluid components. Constant awareness for new allergens, confirmed by critical evaluation, standardization of patch test materials, and the identification of temporal patterns and subgroups at risk will improve both the diagnosis and prevention of allergic contact dermatitis.

Investigation of contact allergy to dental materials by patch testing

PubMed Central

Rai, Reena; Dinakar, Devina; Kurian, Swetha S.; Bindoo, Y. A.

2014-01-01

Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG). Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials. PMID:25165644

Pediatric Contact Dermatitis Registry Inaugural Case Data.

PubMed

Goldenberg, Alina; Mousdicas, Nico; Silverberg, Nanette; Powell, Douglas; Pelletier, Janice L; Silverberg, Jonathan I; Zippin, Jonathan; Fonacier, Luz; Tosti, Antonella; Lawley, Leslie; Wu Chang, Mary; Scheman, Andrew; Kleiner, Gary; Williams, Judith; Watsky, Kalman; Dunnick, Cory A; Frederickson, Rachel; Matiz, Catalina; Chaney, Keri; Estes, Tracy S; Botto, Nina; Draper, Michelle; Kircik, Leon; Lugo-Somolinos, Aida; Machler, Brian; Jacob, Sharon E

2016-01-01

Little is known about the epidemiology of allergic contact dermatitis (ACD) in US children. More widespread diagnostic confirmation through epicutaneous patch testing is needed. The aim was to quantify patch test results from providers evaluating US children. The study is a retrospective analysis of deidentified patch test results of children aged 18 years or younger, entered by participating providers in the Pediatric Contact Dermatitis Registry, during the first year of data collection (2015-2016). One thousand one hundred forty-two cases from 34 US states, entered by 84 providers, were analyzed. Sixty-five percent of cases had one or more positive patch test (PPT), with 48% of cases having 1 or more relevant positive patch test (RPPT). The most common PPT allergens were nickel (22%), fragrance mix I (11%), cobalt (9.1%), balsam of Peru (8.4%), neomycin (7.2%), propylene glycol (6.8%), cocamidopropyl betaine (6.4%), bacitracin (6.2%), formaldehyde (5.7%), and gold (5.7%). This US database provides multidisciplinary information on pediatric ACD, rates of PPT, and relevant RPPT reactions, validating the high rates of pediatric ACD previously reported in the literature. The registry database is the largest comprehensive collection of US-only pediatric patch test cases on which future research can be built. Continued collaboration between patients, health care providers, manufacturers, and policy makers is needed to decrease the most common allergens in pediatric consumer products.

Polyethylene glycol as marker for nitrofurazone allergy: 20 years of experience from Turkey.

PubMed

Özkaya, Esen; Kılıç, Sıla

2018-03-01

Polyethylene glycols (PEGs) and propylene glycol (PG) are used as vehicles in various medicinal and cosmetic products. They are potential contact sensitizers, including low molecular weight PEGs in nitrofurazone preparations that are still widely used in Turkey. To investigate the prevalence of allergic contact dermatitis caused by PEG and PG in a relatively large group of patients in Turkey. In this retrospective, cross-sectional, single-centre study, 836 patients patch tested with PEG and PG between 1996 and 2015 were reviewed. Thirty-five patients (4.2%) showed positive patch test reactions to PEG, and 7 (0.8%) showed positive patch test reactions to PG, partly as late positive reactions with PEG. PEG sensitivity was almost exclusively related to nitrofurazone allergy. Patch test reactions to PG were currently relevant mainly with regard to the use of minoxidil, and antiherpetic or corticosteroid creams. Ten patients (25%) had concomitant contact allergies to various topical drugs containing mainly PEGs. PEG sensitivity seems to be a marker for contact allergy to topical nitrofurazone in Turkey. Nitrofurazone allergy appears to favour concomitant sensitization to PEG. We would suggest the inclusion of PEG in an extended baseline patch test series in Turkey. Late patch test readings are important to diagnose delayed positive reactions to PEG. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Results of patch testing with lavender oil in Japan.

PubMed

Sugiura, M; Hayakawa, R; Kato, Y; Sugiura, K; Hashimoto, R

2000-09-01

We report the annual results of patch testing with lavender oil for a 9-year period from 1990 to 1998 in Japan. Using Finn Chambers and Scanpor tape, we performed 2-day closed patch testing with lavender oil 20% pet. on the upper back of each patient suspected of having cosmetic contact dermatitis. We compared the frequency of positive patch tests to lavender oil each year with those to other fragrances. We diagnosed contact allergy when patch test reactions were + or <+ at 1 day after removal. The positivity rate of lavender oil was 3.7% (0-13.9%) during the 9-year period from 1990 to 1998. The positivity rate of lavender oil increased suddenly in 1997. Recently, in Japan, there has been a trend for aromatherapy using lavender oil. With this trend, placing dried lavender flowers in pillows, drawers, cabinets, or rooms has become a new fashion. We asked patients who showed a positive reaction to lavender oil about their use of dried lavender flowers. We confirmed the use of dried lavender flowers in 5 cases out of 11 positive cases in 1997 and 8 out of 15 positive cases in 1998. We concluded that the increase in patch test positivity rates to lavender oil in 1997 and 1998 was due to the above fashion, rather than due to fragrances in cosmetic products.

Patch tests with fragrance materials and preservatives.

PubMed

de Groot, A C; Liem, D H; Nater, J P; van Ketel, W G

1985-02-01

179 patients suspected of cosmetic allergy were patch tested with a series of 16 fragrance materials and 9 preservatives. In 67 patients (37.4%), 1 or more of these substances gave positive reactions. In the group of fragrance materials, the largest numbers of positive patch test reactions were seen to isoeugenol, oak moss, geraniol, alpha-amylcinnamic alcohol, and a mixture of alpha-amylcinnamic aldehyde and alpha-hexylcinnamic aldehyde. The fragrance mix in the ICDRG standard series detected nearly 80% of cases of contact allergy to fragrance materials other than its constituents. In the group of preservatives, Kathon CG and quaternium-15 scored the highest number of positive reactions. It is argued that the commonly used patch test concentrations of 2% for oak moss and geraniol may be too low to detect all cases of sensitization.

Eyelid Dermatitis: Contact Allergy to 3-(Dimethylamino)propylamine

PubMed Central

Knopp, Eleanor; Watsky, Kalman

2014-01-01

We present the case of a 42-year-old woman with intractable eyelid dermatitis. Patch testing revealed sensitization to 3-(dimethylamino)propylamine (DMAPA). DMAPA is an important etiology of allergic contact dermatitis of the eyelids and face but is easily missed even with expanded-series patch testing. We also review the most common causative allergens in eyelid dermatitis cited in the literature over the past decade. DMAPA is a reagent used in the formation of cocamidopropyl betaine (CAPB), a common additive to liquid soaps, shampoos, and other cleansing products because of its utility as a surfactant. Beginning in the 1980s, reports of allergy to CAPB surfaced in the literature. Ultimately, a majority of patch testing studies have shown that clinical allergy to CAPB-containing products actually reflects allergy to contaminant DMAPA in most cases. Amidoamine, another intermediate in the formation of CAPB, may also be implicated through a proposed mechanism of conversion to DMAPA in the skin. When patch-testing for eyelid and facial dermatitis, it is crucial to test with DMAPA directly, not just with CAPB; unlike commercial-grade CAPB, the CAPB in patch test kits is ultrapure and does not contain contaminant DMAPA. PMID:19134437

Is the European standard series suitable for patch testing in Riyadh, Saudi Arabia?

PubMed

el-Rab, M O; al-Sheikh, O A

1995-11-01

Due to the lack of a regional patch test series in our geographical area, the suitability of the European standard series was evaluated by patch testing dermatitis patients in Riyadh, Saudi Arabia. Of 240 consecutive patients with various forms of dermatitis, 136 (57%) showed 1 or more positive patch tests, women, 74 (54%), slightly outnumbering men, 62 (46%). Positive reactions were found to 21 of the 22 items in the test series. Sensitization was most common to nickel sulfate (51 = 37.5%), potassium dichromate (48 = 35%) and cobalt chloride (43 = 32%) The frequency of sensitization to nickel was higher in women (41 = 30%) while that to dichromate was higher in men (39 = 29%). Less reactions were found to fragrance mix (21 = 15%), formaldehyde (15 = 11%) and neomycin sulfate (15 = 11%). Sensitization to other allergens ranged between 10 and 1%. Less than 1% of patients (0.7%) reacted to benzocaine and none to primin. The frequency of occurrence of multiple sensitivities is also presented. We conclude that the European standard series is suitable for patch testing dermatitis patients in our region, with the exception of benzocaine and primin. The addition of 3 allergens that could be of local relevance is discussed.

The blockade of excitation/contraction coupling by nifedipine in patch-clamped rat skeletal muscle cells in culture.

PubMed

Cognard, C; Rivet, M; Raymond, G

1990-04-01

The effects of the dihydropyridine derivative, nifedipine, well known as a blocker of calcium channels, were tested on cultured rat myoballs. Membrane currents and contractions were simultaneously recorded by means of the patch-clamp technique and a photoelectric transducing method. High concentrations of nifedipine (5 microM) inhibited the contractile responses and inward calcium current (ICa) elicited by long depolarizations. In the absence of ICa (1.5 mM cadmium in the bath), nifedipine inhibited both the ICa-independent contractile component and the outward current, supposed to depend on the intracellular calcium released during contraction. At low concentrations (0.5 microM) the blocking effects of nifedipine could be strongly enhanced by shifting the membrane potential towards less negative values (-60 mV) for 50 s prior to the test pulse. A blocking effect of nifedipine, at a usually ineffective concentration (0.1 microM), could also be observed when long-lasting (3 min) prepulses to 0 mV were applied from a reference membrane potential of -60 mV. This effect could be relieved by long-lasting cell hyperpolarizations (-90 mV). The blocking effects of nifedipine unrelated to ICa could be interpreted as an action on a molecule (voltage sensor) in the T-tubule membrane involved in the excitation/contraction coupling process and as a preferential binding of the dihydropyridine derivative on the inactivated form of this molecule, favored by the weak negative potentials or long-lasting depolarizations. The results provide data in favor of the existence of strong similarities between the calcium channels and voltage sensors since their operation was inhibited in a voltage-dependent manner by nifedipine.

Portable Holographic Interferometry Testing System: Application to crack patching quality control

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

Heslehurst, R.B.; Baird, J.P.; Williamson, H.M.

Over recent years the repair of metallic structures has been improved through the use of patches fabricated from composite materials and adhesively bonded to the damaged area. This technology is termed crack patching, and has been successfully and extensively used by the RAAF and the USAF. However, application of the technology to civilian registered aircraft has had limited success due to the apparent lack of suitable quality assurance testing methods and the airworthiness regulators concern overpatch adhesion integrity. Holographic interferometry has previously shown the advantages of detecting out-of-plane deformations of the order of the wavelength of light (1{mu}). Evidence willmore » be presented that holography is able to detect changes in load path due to debonds and weakened adhesion in an adhesively bonded patch. A Portable Holographic Interferometry Testing System (PHITS) which overcomes the vibration isolation problem associated with conventional holography techniques has been developed. The application of PHITS to crack patching technology now provides a suitable method to verify the integrity of bonded patches in-situ.« less

Nicotine patches improve mood and response speed in a lexical decision task.

PubMed

Gentry, M V; Hammersley, J J; Hale, C R; Nuwer, P K; Meliska, C J

2000-01-01

The effects of smoking a cigarette or wearing a transdermal nicotine patch on mood and lexical decision-making were tested in eight smokers. Each participant was tested after 4 hours of smoking abstinence, under 4 conditions: placebo (very low nicotine) cigarette, nicotine cigarette, placebo patch, and nicotine patch. Relative to placebo, wearing the nicotine patch reduced Profile of Mood States (POMS) Total Mood Disturbance and Fatigue/Inertia scores, while increasing the speed of some types of lexical decisions. Smoking a nicotine cigarette did not affect reaction times, but unexpectedly decreased the accuracy of Word/ Nonword lexical decisions. Thus, transdermal nicotine may improve mood and facilitate longterm memory search and/or attentional processes in nicotine-deprived smokers.

Stiffness and strength of fiber reinforced polymer composite bridge deck systems

NASA Astrophysics Data System (ADS)

Zhou, Aixi

This research investigates two principal characteristics that are of primary importance in Fiber Reinforced Polymer (FRP) bridge deck applications: STIFFNESS and STRENGTH. The research was undertaken by investigating the stiffness and strength characteristics of the multi-cellular FRP bridge deck systems consisting of pultruded FRP shapes. A systematic analysis procedure was developed for the stiffness analysis of multi-cellular FRP deck systems. This procedure uses the Method of Elastic Equivalence to model the cellular deck as an equivalent orthotropic plate. The procedure provides a practical method to predict the equivalent orthotropic plate properties of cellular FRP decks. Analytical solutions for the bending analysis of single span decks were developed using classical laminated plate theory. The analysis procedures can be extended to analyze continuous FRP decks. It can also be further developed using higher order plate theories. Several failure modes of the cellular FRP deck systems were recorded and analyzed through laboratory and field tests and Finite Element Analysis (FEA). Two schemes of loading patches were used in the laboratory test: a steel patch made according to the ASSHTO's bridge testing specifications; and a tire patch made from a real truck tire reinforced with silicon rubber. The tire patch was specially designed to simulate service loading conditions by modifying real contact loading from a tire. Our research shows that the effects of the stiffness and contact conditions of loading patches are significant in the stiffness and strength testing of FRP decks. Due to the localization of load, a simulated tire patch yields larger deflection than the steel patch under the same loading level. The tire patch produces significantly different failure compared to the steel patch: a local bending mode with less damage for the tire patch; and a local punching-shear mode for the steel patch. A deck failure function method is proposed for predicting the failure of FRP decks. Using developed laminated composite theories and FEA techniques, a strength analysis procedure containing ply-level information was proposed and detailed for FRP deck systems. The behavior of the deck's unsupported (free) edges was also investigated using ply-level FEA.

Severe allergic reactions to para-phenylenediamine in children and adolescents: should the patch test concentration of PPD be changed?

PubMed

Spornraft-Ragaller, Petra; Kämmerer, Eva; Gillitzer, Claus; Schmitt, Jochen

2012-04-01

Semipermanent henna tattoos containing para-phenylenediamine (PPD) are a well-known cause of severe contact dermatitis, mainly in children. Another relevant exposure source to PPD are hair dyes, which are increasingly used by children and have also been reported to cause intense facial and scalp dermatitis. German patch test guidelines for children recommend that PPD should only be tested in patients who have had a henna tattoo, and then at a reduced concentration of PPD 0.5 % for 24 hours. We report on patch test results in four patients, three children and one adolescent, with a history of contact dermatitis to henna tattoos or hair dye. We used the recommended or even lower patch test concentrations of PPD with 24-hours exposure in all patients. All patients showed very strong patch test reactions to PPD and cross-reactions to related compounds even after dilution of PPD to as low as 0.05 %. Therefore, we suggest that in children with a history of allergic reactions to this compound, a titration test should be performed beginning at a concentration of maximal 0.05 %. This procedure has also been proposed previously based on a larger cases series in adults. © The Authors • Journal compilation © Blackwell Verlag GmbH, Berlin.

Contact allergy to chlorhexidine in a tertiary dermatology clinic in Denmark.

PubMed

Opstrup, Morten S; Johansen, Jeanne D; Zachariae, Claus; Garvey, Lene H

2016-01-01

Chlorhexidine is a widely used disinfectant in the healthcare setting and in cosmetic products. A high prevalence of chlorhexidine contact allergy was reported in Denmark in the 1980s (2.0-5.4% of patients patch tested). It is unknown whether the prevalence is still high, which products cause the contact allergy, and whether accidental re-exposure occurs in some patients. To estimate the prevalence of chlorhexidine contact allergy in a tertiary dermatology clinic in Denmark; to investigate whether patch testing with both chlorhexidine diacetate and chlorhexidine digluconate is necessary; to investigate how many patients have combined immediate-type allergy and contact allergy; and to identify which products cause chlorhexidine contact allergy, and whether patients are accidentally re-exposed. This was a retrospective study including all patients patch tested with chlorhexidine during 2003-2013 at the Department of Dermato-Allergology at Copenhagen University Hospital Gentofte (n = 8497). All patients with a positive patch test reaction to chlorhexidine were sent a questionnaire comprising questions about the cause of the allergy and re-exposure. Overall, 1.0% (n = 82) of all patients patch tested with chlorhexidine were positive. A decrease in the prevalence was observed over time, most likely because of lowering of the test concentration from 1.0 to 0.5% in 2008. Of the 82 patients, 28 (0.3%) had positive test reactions to both chlorhexidine salts, 43 (0.5%) had a positive test reaction only to chlorhexidine diacetate, and 11 (0.1%) had a positive test reaction to chlorhexidine digluconate. Three patients were both patch test-positive and prick test-positive. A known cause of the allergy was reported by 19 patients (40%) in the questionnaire: the products used in the healthcare setting were mainly reported, but some reported cosmetic products. Accidental re-exposure was reported by 15 patients (32%), of whom 13 reported symptoms. The prevalence of chlorhexidine contact allergy does not seem to be higher in Denmark than in other European countries. Patch testing with both chlorhexidine diacetate and chlorhexidine digluconate may be beneficial. Testing for immediate-type allergy in patients with a positive patch test reaction to chlorhexidine is recommended. Chlorhexidine-containing products used in the healthcare setting and in cosmetics are potential causes of sensitization and allergy. Re-exposure is common, highlighting the fact that patients and healthcare personnel need to be well informed about possible sources of exposure. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Flu Vaccine Skin Patch Tested

MedlinePlus

... 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 ...

Risk factors and common contact allergens in facial allergic contact dermatitis patients.

PubMed

Kasemsarn, Pranee; Iamphonrat, Thanawan; Boonchai, Waranya

2016-04-01

Facial dermatitis is commonly encountered in dermatologic practice. It is sometimes difficult to manage because its causative factors may be multiple and difficult to diagnose. This study was designed to identify the characteristics, patch test results, and final diagnoses of facial dermatitis patients who were referred to a contact dermatitis clinic and to identify factors associated with facial allergic contact dermatitis (ACD). We retrospectively reviewed case records of facial dermatitis patients who underwent patch testing at the clinic during the period from July 2006 to June 2011. Of the 891 patients patch-tested, 244 (27.4%) had facial dermatitis. Female patients were 9.1 times more predominant than male patients. The mean ± standard deviation age of patients was 37.3 ± 14.8 years. A total of 199 (81.6%) patients demonstrated at least one positive reaction to a patch test, 66.7% of which were clinically relevant. Allergic contact dermatitis was diagnosed in 45.5% of patients. Independent factors predisposing towards facial dermatitis were female sex, having a previous history of cosmetic allergy, a positive patch test reaction to hairdressing product-related allergens, and a positive allergic reaction to preservative allergens. The prevalence of facial dermatitis was 27.4%. Almost half of all patients with facial dermatitis demonstrated ACD. Factors associated with facial ACD were female gender, a history of cosmetic allergy, and positive patch test reactions to hairdressing product-related allergens and preservatives. © 2015 The International Society of Dermatology.

The effectiveness of an adhesively bonded composite patch repair as applied to a transport aircraft lower wing skin

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

Ruschau, J.J.; Coate, J.E.

1996-12-31

Specimens were machined from lower wing skin extrusions of a transport aircraft, precracked under fatigue loading, repaired with a boron/epoxy patch, and subsequently fatigue tested under simulated flight loading conditions to evaluate the effectiveness of an adhesively bonded repair patch. Testing was performed at RT and -54{degrees}C for two configurations: one with the crack running up the integral stiffener (riser), the other running down the riser towards the outer skin surface. Cracks were initiated from a single 6.35 mm diameter hole located in the riser portion of the 7075-T6 wing skin material. Ultrasonic inspections were performed during fatigue loading tomore » determine crack growth and damage underneath the patch. Limited results show the adhesively bonded patch was successful in stopping or greatly reducing any further crack growth. Under laboratory air conditions, no crack growth occurred following 30,000 equivalent flight hours, double the expected life of the patched structure. Similarly at -54{degrees}C, no crack growth was observed for a patched crack growing up the riser following 15,000 EFH. For the case of a crack growing down the riser at the lower test temperature, some crack growth was measured, though at a greatly reduced rate.« less

EAACI position paper for practical patch testing in allergic contact dermatitis in children.

PubMed

de Waard-van der Spek, Flora B; Darsow, Ulf; Mortz, Charlotte G; Orton, David; Worm, Margitta; Muraro, Antonella; Schmid-Grendelmeier, Peter; Grimalt, Ramon; Spiewak, Radoslaw; Rudzeviciene, Odilija; Flohr, Carsten; Halken, Susanne; Fiocchi, Alessandro; Borrego, Luis Miguel; Oranje, Arnold P

2015-11-01

Allergic contact dermatitis (ACD) in children appears to be on the increase, and contact sensitization may already begin in infancy. The diagnosis of contact dermatitis requires a careful evaluation of a patient's clinical history, physical examination, and skin testing. Patch testing is the gold standard diagnostic test. Based on consensus, the EAACI Task Force on Allergic Contact Dermatitis in Children produced this document to provide details on clinical aspects, the standardization of patch test methodology, and suggestions for future research in the field. We provide a baseline list of test allergens to be tested in children with suspected ACD. Additional tests should be performed only on specific indications. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of Two-Pore Channel 2 by Nuclear Membrane Electrophysiology

PubMed Central

Lee, Claire Shuk-Kwan; Tong, Benjamin Chun-Kit; Cheng, Cecily Wing-Hei; Hung, Harry Chun-Hin; Cheung, King-Ho

2016-01-01

Lysosomal calcium (Ca2+) release mediated by NAADP triggers signalling cascades that regulate many cellular processes. The identification of two-pore channel 2 (TPC2) as the NAADP receptor advances our understanding of lysosomal Ca2+ signalling, yet the lysosome is not amenable to traditional patch-clamp electrophysiology. Previous attempts to record TPC2 single-channel activity put TPC2 outside its native environment, which not reflect TPC2’s true physiological properties. To test the feasibility of using nuclear membrane electrophysiology for TPC2 channel characterization, we constructed a stable human TPC2-expressing DT40TKO cell line that lacks endogenous InsP3R and RyR (DT40TKO-hTPC2). Immunostaining revealed hTPC2 expression on the ER and nuclear envelope. Intracellular dialysis of NAADP into Fura-2-loaded DT40TKO-hTPC2 cells elicited cytosolic Ca2+ transients, suggesting that hTPC2 was functionally active. Using nuclear membrane electrophysiology, we detected a ~220 pS single-channel current activated by NAADP with K+ as the permeant ion. The detected single-channel recordings displayed a linear current-voltage relationship, were sensitive to Ned-19 inhibition, were biphasically regulated by NAADP concentration, and regulated by PKA phosphorylation. In summary, we developed a cell model for the characterization of the TPC2 channel and the nuclear membrane patch-clamp technique provided an alternative approach to rigorously investigate the electrophysiological properties of TPC2 with minimal manipulation. PMID:26838264

A large contribution of a cyclic AMP-independent pathway to turtle olfactory transduction

PubMed Central

1994-01-01

Although multiple pathways are involved in the olfactory transduction mechanism, cAMP-dependent pathway has been considered to contribute mainly to the transduction. We examined the degree of contribution of cAMP-independent pathway to the turtle olfactory response by recording inward currents from isolated cells, nerve impulses from cilia and olfactory bulbar responses. The results obtained by the three recordings were essentially consistent with each other, but detail studies were carried out by recording the bulbar response to obtain quantitative data. Application of an odorant cocktail to the isolated olfactory neuron after injection of 1 mM cAMP from the patch pipette elicited a large inward current. Mean amplitude of inward currents evoked by the cocktail with 1 mM cAMP in the patch pipette was similar to that without cAMP in the pipette. Application of the cocktail after the response to 50 microM forskolin was adapted also induced a large inward current. Application of the odorant cocktail to the olfactory epithelium, after the response to 50 microM forskolin was adapted, brought about an appreciable increase in the impulse frequency. The bulbar response to forskolin alone reached a saturation level around 10 microM. After the response to 50 microM forskolin was adapted, 11 species of odorants were applied to the olfactory epithelium. The magnitudes of responses to the odorants after forskolin were 45-80% of those of the control responses. There was no essential difference in the degree of the suppression by forskolin between cAMP- and IP3- producing odorants classified in the rat, suggesting that certain part of the forskolin-suppressive component was brought about by nonspecific action of forskolin. Application of a membrane permeant cAMP analogue, cpt-cAMP elicited a large response, and 0.1 mM citralva after 3 mM cpt- cAMP elicited 51% of the control response which was close to the response to citralva after 50 microM forskolin. A membrane permeant cGMP analogue, db-cGMP elicited a small response and the response to 0.1 mM citralva was unaffected by db-cGMP. It was concluded that cAMP- independent (probably IP3-independent) pathway greatly contributes to the turtle olfactory transduction. PMID:7523576

Contact allergy to oxidized geraniol among Swedish dermatitis patients-A multicentre study by the Swedish Contact Dermatitis Research Group.

PubMed

Hagvall, Lina; Bruze, Magnus; Engfeldt, Malin; Isaksson, Marléne; Lindberg, Magnus; Ryberg, Kristina; Stenberg, Berndt; Svedman, Cecilia; Karlberg, Ann-Therese; Bråred Christensson, Johanna

2018-06-21

Geraniol is a widely used fragrance terpene, and is included in fragrance mix I. Geraniol is prone to autoxidation, forming the skin sensitizers geranial, neral, and geraniol-7-hydroperoxide. Oxidized geraniol has previously been patch tested in 1 clinic, giving 1% to 4.6% positive reactions in consecutive patients when tested at 2% to 11%. To compare test reactions to pure and oxidized geraniol, to compare 2 different test concentrations of oxidized geraniol and to investigate the pattern of concomitant reactions to fragrance markers of the baseline series in a multicentre setting. One thousand four hundred and seventy-six consecutive patients referred for patch testing were patch tested with geraniol 6% pet. and oxidized geraniol 6% and 11% pet. Pure geraniol 6% pet., oxidized geraniol 6% pet. and oxidized geraniol 11% pet. gave 1%, 3% and 8% positive patch test reactions and 0.7%, 3% and 5% doubtful reactions, respectively. Approximately 50% of the patients with doubtful reactions to oxidized geraniol 6% pet. had positive reactions to oxidized geraniol 11% pet. Oxidized geraniol 11% pet. provides better detection than oxidized geraniol 6% pet. As most patients reacted only to oxidized geraniol, it is important to explore further whether oxidized geraniol should be included in a baseline patch test series. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Lyral has been included in the patch test standard series in Germany.

PubMed

Geier, Johannes; Brasch, Jochen; Schnuch, Axel; Lessmann, Holger; Pirker, Claudia; Frosch, Peter J

2002-05-01

Lyral 5% pet. was tested in 3245 consecutive patch test patients in 20 departments of dermatology in order (i) to check the diagnostic quality of this patch test preparation, (ii) to examine concomitant reactions to Lyral and fragrance mix (FM), and (iii) to assess the frequency of contact allergy to Lyral in an unselected patch test population of German dermatological clinics. 62 patients reacted to Lyral, i.e. 1.9%. One third of the positive reactions were + + and + + +. The reaction index was 0.27. Thus, the test preparation can be regarded a good diagnostic tool. Lyral and fragrance mix (FM) were tested in parallel in 3185 patients. Of these, 300 (9.4%) reacted to FM, and 59 (1.9%) to Lyral. In 40 patients, positive reactions to both occurred, which is 13.3% of those reacting to FM, and 67.8% of those reacting to Lyral. So the concordance of positive test reactions to Lyral and FM was only slight. Based on these results, the German Contact Dermatitis Research Group (DKG) decided to add Lyral 5% pet. to the standard series.

Neural effects of methylphenidate and nicotine during smooth pursuit eye movements.

PubMed

Kasparbauer, Anna-Maria; Meyhöfer, Inga; Steffens, Maria; Weber, Bernd; Aydin, Merve; Kumari, Veena; Hurlemann, Rene; Ettinger, Ulrich

2016-11-01

Nicotine and methylphenidate are putative cognitive enhancers in healthy and patient populations. Although they stimulate different neurotransmitter systems, they have been shown to enhance performance on overlapping measures of attention. So far, there has been no direct comparison of the effects of these two stimulants on behavioural performance or brain function in healthy humans. Here, we directly compare the two compounds using a well-established oculomotor biomarker in order to explore common and distinct behavioural and neural effects. Eighty-two healthy male non-smokers performed a smooth pursuit eye movement task while lying in an fMRI scanner. In a between-subjects, double-blind design, subjects either received placebo (placebo patch and capsule), nicotine (7mg nicotine patch and placebo capsule), or methylphenidate (placebo patch and 40mg methylphenidate capsule). There were no significant drug effects on behavioural measures. At the neural level, methylphenidate elicited higher activation in left frontal eye field compared to nicotine, with an intermediate response under placebo. The reduced activation of task-related regions under nicotine could be associated with more efficient neural processing, while increased hemodynamic response under methylphenidate is interpretable as enhanced processing of task-relevant networks. Together, these findings suggest dissociable neural effects of these putative cognitive enhancers. Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of patch shape and connectivity on nest site selection and reproductive success of the Indigo Bunting.

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

Weldon, Aimee Jean

2004-07-01

Description – Ph.D Dissertation. North Carolina State University. Raleigh, North Carolina. 135 pp. Abatract - Habitat fragmentation and its associated effects have been blamed for the recent population declines of many Neotropical migratory bird species. Increased predation and parasitism resulting from edge-related effects have been implicated for poor nesting success in many studies, mostly of forest interior species. However, little attention has been devoted to disturbance-dependent birds. In this study, I examine how patch shape and connectivity in fragmented landscapes affects the reproductive success of disturbance-dependent bird species, specifically the Indigo Bunting (Passerina cyanea). I conducted my study in amore » landscape-scale experimental system of similar-area habitat patches that differed in connectivity and in shape. Shapes differed between edgy and rectangular forms, where edgy patches contained 50% more edge than rectangular patches. I tested whether edgy patches function as ecological traps for species with strong edge preferences, by leading them to select dangerous habitats. Indigo Buntings preferentially selected edgy patches over rectangular patches, but experienced significantly lower reproductive success in edgy patches early in the season. Although predation pressure intensified in rectangular patches late in the season, seasonal fecundity was still significantly lower in edgy patches, providing the first empirical evidence that edges can function as ecological traps for Indigo Buntings. A second objective of my study was to evaluate the efficacy of conservation corridors for disturbance-dependent bird species. Conservation corridors have become a popular strategy to preserve biodiversity and promote gene flow in fragmented landscapes, but corridors may also have negative consequences. I tested the hypothesis that corridors can increase nest predation risk in connected patches relative to unconnected patches. Nest predation rates increased significantly in connected patches compared to unconnected rectangular patches, but were similar between connected patches and unconnected edgy patches. This suggests that the increase in predator activity in connected patches is largely attributable to edge effects incurred through the addition of a corridor. This is the first landscape-scale study to experimentally demonstrate the potential negative effects of conservation corridors.« less

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

PubMed Central

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

2018-01-01

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

Ethylhexylglycerin: a low-risk, but highly relevant, sensitizer in 'hypo-allergenic' cosmetics.

PubMed

Aerts, Olivier; Verhulst, Lien; Goossens, An

2016-05-01

Ethylhexylglycerin is a relatively new cosmetic ingredient that is used for its surfactant, emollient, skin-conditioning and antimicrobial properties. Since 2002, it has been occasionally reported as a contact allergen. To report on 13 patients who presented with allergic contact dermatitis caused by ethylhexylglycerin, evaluated at two Belgian university patch test clinics during the period 1990-2015. The patients were patch tested with the European baseline series, a cosmetic series, and - if indicated - additional series. Both the cosmetic products used and their single ingredients were patch tested. All but one of the ethylhexylglycerin-allergic patients were female, with a median age of 43 years (range: 29-81 years), most often suffering from dermatitis on the face, and sometimes on the hands and/or axillae. As the culprit products, leave-on cosmetics were identified, including a high number of proclaimed 'hypo-allergenic' and 'preservative-free' facial creams, sun protection creams, and deodorants. Ethylhexylglycerin is a rare, but highly relevant, cosmetic sensitizer, even in those products advertised to be safe for consumers. Targeted patch testing with ethylhexylglycerin 5% pet. is very useful, and routine patch testing in a cosmetic series may be considered. Higher test concentrations might be indicated in selected cases. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Recommendation to test limonene hydroperoxides 0·3% and linalool hydroperoxides 1·0% in the British baseline patch test series.

PubMed

Wlodek, C; Penfold, C M; Bourke, J F; Chowdhury, M M U; Cooper, S M; Ghaffar, S; Green, C; Holden, C R; Johnston, G A; Mughal, A A; Reckling, C; Sabroe, R A; Stone, N M; Thompson, D; Wilkinson, S M; Buckley, D A

2017-12-01

There is a significant rate of sensitization worldwide to the oxidized fragrance terpenes limonene and linalool. Patch testing to oxidized terpenes is not routinely carried out; the ideal patch test concentration is unknown. To determine the best test concentrations for limonene and linalool hydroperoxides, added to the British baseline patch test series, to optimize detection of true allergy and to minimize irritant reactions. During 2013-2014, 4563 consecutive patients in 12 U.K. centres were tested to hydroperoxides of limonene in petrolatum (pet.) 0·3%, 0·2% and 0·1%, and hydroperoxides of linalool 1·0%, 0·5% and 0·25% pet. Irritant reactions were recorded separately from doubtful reactions. Concomitant reactions to other fragrance markers and clinical relevance were documented. Limonene hydroperoxide 0·3% gave positive reactions in 241 (5·3%) patients, irritant reactions in 93 (2·0%) and doubtful reactions in 110 (2·4%). Linalool hydroperoxide 1·0% gave positive reactions in 352 (7·7%), irritant reactions in 178 (3·9%) and doubtful reactions in 132 (2·9%). A total of 119 patients with crescendo reactions to 0·3% limonene would have been missed if only tested with 0·1% and 131 patients with crescendo reactions to 1·0% linalool would have been missed if only tested with 0·25%. In almost two-thirds of patients with positive patch tests to limonene and linalool the reaction was clinically relevant. The majority of patients did not react to any fragrance marker in the baseline series. We recommend that limonene hydroperoxides be tested at 0·3% and linalool hydroperoxides at 1·0% in the British baseline patch test series. © 2017 British Association of Dermatologists.

Diagnosing Allergic Contact Dermatitis Through Elimination, Perception, Detection and Deduction.

PubMed

Pongpairoj, Korbkarn; Puangpet, Pailin; Thaiwat, Supitchaya; McFadden, John P

2017-10-01

Several authors have commented upon the skills of detection required in making a diagnosis of allergic contact dermatitis. Here, we emphasise the search for clues in a systematic manner. We describe four stages as part of a systematic method for diagnosing allergic contact dermatitis. Firstly, elimination (or inclusion) of non-allergic diagnoses. Secondly, perception: the pre-patch test diagnosis and the 'three scenarios' principle. Thirdly, detection: optimising the sensitivity of the patch test process. Fourthly, deduction: diagnosing allergic contact dermatitis by associating the dermatitis with the allergen exposure. We further compare and contrast the pre-patch test history and examination with the markedly different one ('microhistory' and 'microexamination') used after patch testing. The importance of knowledge of contact dermatitis literature is emphasised with a review of recent publications. Finally, we also highlight the use of contact allergy profiling as an investigative tool in the diagnosis of allergic contact dermatitis.

[Epidemiology of contact hypersensitivity to rubber components in manufacturers of automobile tires at the Stomil plant].

PubMed

Rubisz-Brzezińska, J; Bogdanowski, T; Brzezińska-Wcisło, L; Mozdzanowska, K; Bajcar, S

1990-01-01

Dermatological examination and patch tests with 34 rubber components were carried out in 114 tire manufacturers, 78 women and 36 men aged 29 years on average, with a mean duration of work in the plant 7 years. For correct interpretation of the obtained results patch tests with the same components were done in two control groups that is in 120 healthy subjects and 120 patients with contact dermatitis. Patch tests with proper concentrations of the studied components were evaluated after 48, 72 and 96 hours. Positive patch tests were found most frequently with antioxidants--16.6% (including IPPD--8.6%), followed by vulcanization accelerators--10.6%, and other rubber components--11.4% in all. During about 3 years of follow-up in 4 manufacturers contact allergic eczema was noted and polyvalent hypersensitivity to antioxidants and vulcanization accelerators without clinical manifestations of this hypersensitivity was diagnosed in 3 other subjects.

Contact Dermatitis to Personal Sporting Equipment in Youth.

PubMed

Marzario, Barbara; Burrows, Dianne; Skotnicki, Sandy

2016-07-01

Contact dermatitis to personal sporting equipment in youth is poorly studied. To review the results of patch testing 6 youth to their sporting equipment in a dermatology general private practice from 2006 to 2011. A retrospective analysis of 6 youth aged 11 to 14 who were evaluated for chronic and persistent dermatitis occurring in relation to sports equipment was conducted. All patients were subjected to epicutaneous (patch) testing, which included some or all of the following: North American Contact Dermatitis Group (NACGD) series, textile series, rubber series, corticosteroid series, and raw material from the patients' own personal equipment. All cases had 1 or more positive patch test reactions to an allergen within the aforementioned series, and 3 subjects tested positive to their personal equipment in raw form. Allergic contact dermatitis, not irritant, was deemed the relevant cause of chronic dermatitis in 4 of the 6 patients due to positive reactions to epicutaneous tests and/or personal equipment. The utility of testing to patients' own sporting equipment was shown to be of additional value and should be considered when patch testing for contact allergy to sporting equipment. © The Author(s) 2015.

Patch test results in children and adolescents. Study from the Santa Casa de Belo Horizonte Dermatology Clinic, Brazil, from 2003 to 2010*

PubMed Central

Rodrigues, Dulcilea Ferraz; Goulart, Eugênio Marcos Andrade

2015-01-01

BACKGROUND Patch testing is an efficient method to identify the allergen responsible for allergic contact dermatitis. OBJECTIVE To evaluate the results of patch tests in children and adolescents comparing these two age groups' results. METHODS Cross-sectional study to assess patch test results of 125 children and adolescents aged 1-19 years, with suspected allergic contact dermatitis, in a dermatology clinic in Brazil. Two Brazilian standardized series were used. RESULTS Seventy four (59.2%) patients had "at least one positive reaction" to the patch test. Among these positive tests, 77.0% were deemed relevant. The most frequent allergens were nickel (36.8%), thimerosal (18.4%), tosylamide formaldehyde resin (6.8%), neomycin (6.4%), cobalt (4.0%) and fragrance mix I (4.0%). The most frequent positive tests came from adolescents (p=0.0014) and females (p=0.0002). There was no relevant statistical difference concerning contact sensitizations among patients with or without atopic history. However, there were significant differences regarding sensitization to nickel (p=0.029) and thimerosal (p=0.042) between the two age groups under study, while adolescents were the most affected. CONCLUSION Nickel and fragrances were the only positive (and relevant) allergens in children. Nickel and tosylamide formaldehyde resin were the most frequent and relevant allergens among adolescents. PMID:26560213

Is Patch Testing with Food Additives Useful in Children with Atopic Eczema?

PubMed

Catli, Gonul; Bostanci, Ilknur; Ozmen, Serap; Dibek Misirlioglu, Emine; Duman, Handan; Ertan, Ulker

2015-01-01

Atopy patch testing is a useful way to determine delayed-type hypersensitivity reactions to foods and aeroallergens. Although food additives have been accused of worsening atopic eczema symptoms, according to recent studies the role of food additives in atopic eczema remains unclear. The purpose of our study was to investigate food additive hypersensitivity in a group of children with atopic eczema by using standardized atopy patch testing and to determine the role of food additive hypersensitivity in atopic eczema. Thirty-four children with atopic eczema and 33 healthy children were enrolled in the study. Children who consumed foods containing additives and did not use either antihistamines or local or systemic corticosteroids for at least 7 days prior to admission were enrolled in the study. All children were subjected to atopy patch testing and after 48 and 72 hours their skin reactions were evaluated by using the guidelines. Positive atopy patch test results were significantly higher in the atopic eczema group. Forty-one percent of the atopic eczema group (n = 14) and 15.2% (n = 5) of the control group had positive atopy patch test results with food additives (p = 0.036) (estimated relative risk 1.68, case odds 0.7, control odds 0.17). Carmine hypersensitivity and the consumption of foods containing carmine, such as gumdrops, salami, and sausage, were significantly higher in the children with atopic eczema. This is the first study investigating hypersensitivity to food additives in children with atopic eczema. Our results indicate that carmine may play a role in atopic eczema. © 2015 Wiley Periodicals, Inc.

[Drug patch tests in the investigation of a fixed drug eruption subsequent to 2 courses of cyclophosphamide in combination with mesna].

PubMed

Delaigue, S; Boye, T; Pasquine, C; Guetta, K; Alla, P; Ponte-Astoul, J; Morand, J-J

2015-01-01

When fixed drug eruption occurs following use of cyclophosphamide and mesna, it is difficult to establish which drug is responsible. We report a new case of patch tests that resulted in withdrawal of mesna and enabled continued treatment with cyclophophamide. A 57-year-old female patient with multiple sclerosis presented increasingly severe cutaneous lesions after successive courses of cyclophosphamide. Twenty-four hours after her latest treatment, she presented at the ER with a worse eruption than those to date and including facial lesions. The clinical diagnosis was a fixed drug eruption, and patch tests for mesna one month later were positive. Fixed drug eruption always occurs after recurrent treatment and the investigation must be precise. Patch tests may be used to determine which drug could be responsible. The most conclusive test comprises withdrawal of the incriminated drug with no further signs of drug eruption on resumption of the other medication. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Patch test reactions to mite antigens: a GERDA multicentre study. Groupe d'Etudes et de Recherches en Dermato-Allergie.

PubMed

Castelain, M; Birnbaum, J; Castelain, P Y; Ducombs, G; Grosshans, E; Jelen, G; Lacroix, M; Meynadier, J; Mougeolle, J M; Lachapelle, J M

1993-11-01

We performed patch tests with Dermatophagoides pteronyssinus (Dp) antigens from 2 different sources in 355 non-randomly selected patients with atopic dermatitis (AD) and 398 subjects of a control group. The study demonstrated that contact sensitization to mites occurred in an appreciable % of AD cases (20.8%), using commonly available assay products. The differences recorded between the 2 materials tested were related to the concentration of P1 antigen. Non-atopic patients rarely showed positive reactions to Dp (0.75%), when strict criteria for readings were applied and if 2 readings were performed. Patients with positive patch tests did not necessarily show positive immediate skin tests. It would be useful to carry out tests systematically in atopic patients, even if it is not yet known what modern treatment would be best for the patient. Laboratories still do not provide standardized house dust mite preparations--measuring and codifying their biological activity--for use in patch tests. It is to be hoped that the extension of this type of test will lead to the production of better test materials, in syringes with homogeneous dispersion and concentration.

A study of tensile residual strength of composite laminates under different patch-repaired series

NASA Astrophysics Data System (ADS)

Ding, M. H.; zhan, S.; Tang, Y. H.; Wang, L.; Ma, D. Q.; Wang, R. G.

2017-09-01

The tensile behavior of composite laminate structures repaired by bonding external patches was studied in the paper. Two different types of patches including wedge patches and inverted wedge patches were used and failure mechanisms, failure load and strength predictions were studied. A convenient and fast method of building 2-D finite element modeling (FEM) of laminate structure repaired was proposed and the strength of repaired laminate structures was calculated by FEM. The results showed that more than 80% tensile strength of the undamaged laminate could be recovered by bonding patch repairs. Moreover, the results indicated that the strength of inverted wedge patches repair were higher than that of wedge patches repair. FEM simulation results indicated that high stress concentration was found along the edges of invert patches and the most weakness part located in the adhesive bondline. FEM analysis results showed that the strength predicted matched well with the test strength.

Limonene hydroperoxide analogues show specific patch test reactions.

PubMed

Christensson, Johanna Bråred; Hellsén, Staffan; Börje, Anna; Karlberg, Ann-Therese

2014-05-01

The fragrance terpene R-limonene is a very weak sensitizer, but forms allergenic oxidation products upon contact with air. The primary oxidation products of oxidized limonene, the hydroperoxides, have an important impact on the sensitizing potency of the oxidation mixture. One analogue, limonene-1-hydroperoxide, was experimentally shown to be a significantly more potent sensitizer than limonene-2-hydroperoxide in the local lymph node assay with non-pooled lymph nodes. To investigate the pattern of reactivity among consecutive dermatitis patients to two structurally closely related limonene hydroperoxides, limonene-1-hydroperoxide and limonene-2-hydroperoxide. Limonene-1-hydroperoxide, limonene-2-hydroperoxide, at 0.5% in petrolatum, and oxidized limonene 3.0% pet. were tested in 763 consecutive dermatitis patients. Of the tested materials, limonene-1-hydroperoxide gave most reactions, with 2.4% of the patients showing positive patch test reactions. Limonene-2-hydroperoxide and oxidized R-limonene gave 1.7% and 1.2% positive patch test reactions, respectively. Concomitant positive patch test reactions to other fragrance markers in the baseline series were frequently noted. The results are in accordance with the experimental studies, as limonene-1-hydroperoxide gave more positive patch test reactions in the tested patients than limonene-2-hydroperoxide. Furthermore, the results support the specificity of the allergenic activity of the limonene hydroperoxide analogues and the importance of oxidized limonene as a cause of contact allergy. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Diagnostic accuracy of patch test in children with food allergy.

PubMed

Caglayan Sozmen, Sule; Povesi Dascola, Carlotta; Gioia, Edoardo; Mastrorilli, Carla; Rizzuti, Laura; Caffarelli, Carlo

2015-08-01

The gold standard test for confirming whether a child has clinical hypersensitivity reactions to foods is the oral food challenge. Therefore, there is increasing interest in simpler diagnostic markers of food allergy, especially in children, to avoid oral food challenge. The goal of this study was to assess the diagnostic accuracy of atopy patch test in comparison with oral food challenge. We investigated 243 children (mean age, 51 months) referred for evaluation of suspected egg or cow's milk allergy. Skin prick test and atopy patch test were carried out, and after a 2 weeks elimination diet, oral food challenge was performed. Two hundred and forty-three children underwent OFC to the suspected food. We found clinically relevant food allergies in 40 (65%) children to egg and in 22 (35%) to cow's milk. The sensitivity of skin prick test for both milk and egg was 92%, specificity 91%, positive predictive value 35%, and negative predictive value of 93%. Sensitivity, specificity, positive predictive value, and negative predictive value of atopy patch test for both milk and egg were 21%, 73%, 20%, and 74%, respectively. Our study suggests that there is insufficient evidence for the routine use of atopy patch test for the evaluation of egg and cow's milk allergy. OFC remains gold standard for the diagnosis of egg and milk allergy even in the presence of high costs in terms of both time and risks during application. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fragrance patch tests prepared in advance may give false-negative reactions.

PubMed

Mowitz, Martin; Svedman, Cecilia; Zimerson, Erik; Bruze, Magnus

2014-11-01

Several of the ingredients in fragrance mix I (FM I) have been shown to evaporate from petrolatum preparations applied in test chambers to an extent that can be suspected to affect the patch test result. To compare the reactivity towards FM I and fragrance mix II (FM II) when they are applied in test chambers in advance and immediately prior to the patch test occasion. Seven hundred and ninety-five consecutive patients were simultaneously patch tested with duplicate samples of FM I and FM II. One sample was applied in the test chamber 6 days in advance (6D sample), and the other sample was applied immediately before the patients were patch tested (fresh sample). Twenty-two (2.8%) patients reacted exclusively to the fresh sample of FM I, 6 (0.7%) reacted exclusively to the 6D sample, and 22 (2.8%) reacted to both samples. The corresponding numbers for FM II were 9 (1.1%) for the fresh sample, 6 (0.7%) for the 6D sample and 12 (1.5%) for both samples. There was a statistically significant difference between the numbers of patients reacting to the fresh and 6D samples of FM I. No corresponding difference was observed for FM II. This can probably be explained by differences in volatilities between the ingredients of FM I and FM II. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multicenter Patch Testing With Methylchloroisothizoline/Methylisothiazolinone in 100 and 200 ppm Within the International Contact Dermatitis Research Group.

PubMed

Engfeldt, Malin; Ale, Iris; Andersen, Klaus E; Elsner, Peter; Goh, Chee-Leok; Goossens, An; Jerajani, Hemangi; Matsunaga, Kayoko; Bruze, Magnus

The preservative methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is a well-known contact sensitizer. Historically, there have been different opinions on the optimal patch test concentration of MCI/MI, and both 0.01% and 0.02% aqueous (aq.) have been proposed. In 2011, based on literature reviews, it was recommended that the concentration of 0.02% aq. should be used in the international baseline series. The aim of this study was to verify the recommendation from 2011 by comparing the patch test results from consecutive patch testing with MCI/MI 0.01% and 0.02% in clinics representing countries around the world. Two thousand seven hundred three consecutive patients with dermatitis in 8 dermatology clinics representing 8 countries were patch tested with MCI/MI 0.01% aq. and, in parallel with MCI/MI 0.02% aq., provisionally included in the baseline series. Contact allergy to MCI/MI at 0.01% and 0.02% was found in 3.7% and 5.6% of the patients, respectively (P < 0.001). Methylchloroisothiazolinone/MI 0.02% aq. (dose, 6 μg/cm) diagnoses significantly more contact allergy than 0.01% (dose, 3 μg/cm), without resulting in more adverse reactions. Methylchloroisothiazolinone/MI at 0.02% aq. should therefore be continuously used in the international baseline series.

Standardizing the Delivery of 20 μL of Hapten During Patch Testing.

PubMed

Selvick, Annika; Stauss, Kari; Strobush, Katrina; Taylor, Lauren; Picard, Alexandra; Doll, Andrea; Reeder, Margo

2016-01-01

The current method for patch test tray assembly requires hand dispensing a small volume of hapten onto chambers. Because of human error, this technique produces inaccurate and inconsistent results. The recommended volume of hapten for patch testing using Finn Chambers is 20 μL. The aims of this study were to create a device that standardizes the delivery of 20 μL and to compare it with the current hand dispensing technique. A device, named the Revolution, was created using the SolidWorks program. Five nurses in our Contact Dermatitis Clinic were asked to load 10 Finn Chambers using the current technique and also using the Revolution. Assembly time, volume of petrolatum, and accuracy of placement were measured. After the 3 trials, the nurses completed a survey on the 2 methods. The amount of petrolatum dispensed using the current technique ranged from 16 to 85 μL, with an average amount of 41.39 μL. The Revolution design dispensed an average of 19.78 μL. The current hand dispensing technique does not allow for accurate and consistent dispensing of 20 μL for patch testing. In contrast, the Revolution is an accurate and consistent device that can help standardize the patch testing method.

Occupational allergic contact dermatitis and patch test results of leather workers at two Indonesian tanneries.

PubMed

Febriana, Sri Awalia; Jungbauer, Frank; Soebono, Hardyanto; Coenraads, Pieter-Jan

2012-11-01

Tannery workers are at considerable risk of developing occupational contact dermatitis. Occupational skin diseases in tannery workers in newly industrialized countries have been reported, but neither the prevalence of occupational allergic contact dermatitis nor the skin-sensitizing agents were specifically examined in those studies. To assess the prevalence of occupational allergic contact dermatitis in Indonesian tanneries, identify the causative allergens, and propose a tannery work series of patch test allergens. A cross-sectional study in all workers at two Indonesian tanneries was performed to assess the prevalence of occupational contact dermatitis via a questionnaire-based interview and skin examination. Workers with occupational contact dermatitis were patch tested to identify the causative allergens. Occupational contact dermatitis was suspected in 77 (16%) of the 472 workers. Thirteen (3%) of these 472 workers were confirmed to have occupational allergic contact dermatitis. Potassium dichromate (9.2%), N,N-diphenylguanidine (5.3%), benzidine (3.9%) and sodium metabisulfite (2.6%) were found to be the occupationally relevant sensitizers. The sensitization pattern showed some differences from the data in studies reported from other newly industrial countries. We compiled a 'tannery work series' of allergens for patch testing. A number of these allergens may also be considered for patch testing in patients with (leather) shoe dermatitis. © 2012 John Wiley & Sons A/S.

Testing a bioenergetics-based habitat choice model: bluegill (Lepomis macrochirus) responses to food availability and temperature

USGS Publications Warehouse

2011-01-01

Using an automated shuttlebox system, we conducted patch choice experiments with 32, 8–12 g bluegill sunfish (Lepomis macrochirus) to test a behavioral energetics hypothesis of habitat choice. When patch temperature and food levels were held constant within patches but different between patches, we expected bluegill to choose patches that maximized growth based on the bioenergetic integration of food and temperature as predicted by a bioenergetics model. Alternative hypotheses were that bluegill may choose patches based only on food (optimal foraging) or temperature (behavioral thermoregulation). The behavioral energetics hypothesis was not a good predictor of short-term (from minutes to weeks) patch choice by bluegill; the behavioral thermoregulation hypothesis was the best predictor. In the short-term, food and temperature appeared to affect patch choice hierarchically; temperature was more important, although food can alter temperature preference during feeding periods. Over a 19-d experiment, mean temperatures occupied by fish offered low rations did decline as predicted by the behavioral energetics hypothesis, but the decline was less than 1.0 °C as opposed to a possible 5 °C decline. A short-term, bioenergetic response to food and temperature may be precluded by physiological costs of acclimation not considered explicitly in the behavioral energetics hypothesis.

An experimental test of whether habitat corridors affect pollen transfer.

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

Townsend, Patricia A.; Levey, Douglas J.

Abstract. Negative effects of habitat fragmentation are thought to be diminished when habitat patches are joined by a corridor. A key assumption is that corridors facilitate exchange rates of organisms between otherwise isolated patches. If the organisms are pollinators, corridors may be important for maintaining genetically viable populations of the plants that they pollinate. We tested the hypothesis that corridors increase the movement of insect pollinators into patches of habitat and thereby increase pollen transfer for two species of plants, one pollinated by butterflies (Lantana camara) and the other by bees and wasps (Rudbeckia hirta). We worked in an experimentalmore » landscape consisting of 40 greater than or equal to 1-ha patches of early-successional habitat in a matrix of forest. Within each of eight experimental units, two patches were connected by a corridor (150 X 25 m), and three were not. Patch shape varied to control for the area added by the presence of a corridor. Differences in patch shape also allowed us to test alternative hypotheses of how corridors might function. The Traditional Corridor Hypothesis posits that corridors increase immigration and emigration by functioning as movement conduits between patches. The Drift Fence Hypothesis posits that corridors function by ‘‘capturing’’ organisms dispersing through the matrix, redirecting them into associated habitat patches. Using fluorescent powder to track pollen, we found that pollen transfer by butterflies between patches connected by a corridor was significantly higher than between unconnected patches (all values mean plus or minus 1 SE: 59% plus or minus 9.2% vs. 25% plus or minus 5.2% of flowers receiving pollen). Likewise, pollen transfer by bees and wasps was significantly higher between connected patches than between unconnected patches (30% plus or minus 4.2% vs. 14.5% plus or minus 2.2%). These results support the Traditional Corridor Hypothesis. There was little support, however, for the Drift Fence Hypothesis. To generalize our results to a larger scale, we measured the probability of pollen transfer by butterflies as a function of distance along a 2000 X 75 m corridor. Pollen transfer probability exponentially declined with respect to distance and successfully predicted pollen transfer probability on the scale of our previous experiment. These results suggest that corridors facilitate pollen transfer in fragmented landscapes.« less

Lack of Association Between Dust Mite Sensitivity and Atopic Dermatitis.

PubMed

Silverberg, Jonathan Ian; Hanifin, Jon M; Law, Sandra; White, Kevin; Storrs, Frances J

2016-01-01

Dust mites (DMs) play a role in type I respiratory allergy. Studies relating to DM irritant versus immune reactions are somewhat conflicting in atopic dermatitis (AD). The aim of this study was to assess the diagnostic use of patch testing to DM in patients with AD and other dermatitides. We performed a prospective study of 323 adults recruited in a patch testing clinic. Patch testing antigens were DM extract (0.01%, 0.1%, 1%, 10%, and 20% in petrolatum; Chemotechnique) and/or 200 index of reactivity in petrolatum (Stallergenes). Patches were placed and read at 48 hours with delayed readings after 72 to 168 hours. There was no association of DM positivity with AD, asthma, hay fever, or demographic factors. There was no association of DM positivity with the clinical diagnosis or phenotype. The number of positive (+, ++, and +++) and doubtful reactions to Chemotechnique DM extract increased with higher concentrations. Positive reactions to DM had a morphological appearance characterized by numerous discrete erythematous papules and, rarely, papulovesicles. Positive reactions to Stallergenes DM 200 IR were infrequent and all weak reactions, similar to DM 0.01%. Patch testing to DM does not seem to have clinical use for determining the etiology of dermatitis.

Ajmaline blocks INa and IKr without eliciting differences between Brugada syndrome patient and control human pluripotent stem cell-derived cardiac clusters.

PubMed

Miller, Duncan C; Harmer, Stephen C; Poliandri, Ariel; Nobles, Muriel; Edwards, Elizabeth C; Ware, James S; Sharp, Tyson V; McKay, Tristan R; Dunkel, Leo; Lambiase, Pier D; Tinker, Andrew

2017-12-01

The class Ia anti-arrhythmic drug ajmaline is used clinically to unmask latent type I ECG in Brugada syndrome (BrS) patients, although its mode of action is poorly characterised. Our aims were to identify ajmaline's mode of action in human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs), and establish a simple BrS hiPSC platform to test whether differences in ajmaline response could be determined between BrS patients and controls. Control hiPSCs were differentiated into spontaneously contracting cardiac clusters. It was found using multi electrode array (MEA) that ajmaline treatment significantly lengthened cluster activation-recovery interval. Patch clamping of single CMs isolated from clusters revealed that ajmaline can block both I Na and I Kr . Following generation of hiPSC lines from BrS patients (absent of pathogenic SCN5A sodium channel mutations), analysis of hiPSC-CMs from patients and controls revealed that differentiation and action potential parameters were similar. Comparison of cardiac clusters by MEA showed that ajmaline lengthened activation-recovery interval consistently across all lines. We conclude that ajmaline can block both depolarisation and repolarisation of hiPSC-CMs at the cellular level, but that a more refined integrated tissue model may be necessary to elicit differences in its effect between BrS patients and controls. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The Association of Race/Ethnicity and Patch Test Results: North American Contact Dermatitis Group, 1998-2006.

PubMed

Deleo, Vincent Anthony; Alexis, Andrew; Warshaw, Erin M; Sasseville, Denis; Maibach, Howard I; DeKoven, Joel; Zug, Kathryn A; Belsito, Donald V; Fowler, Joseph F; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Rietschel, Robert L; Storrs, Frances J; Taylor, James S; Zirwas, Matthew

2016-01-01

The North American Contact Dermatitis Group patch tests patients with suspected allergic contact dermatitis (ACD) to a broad series of screening allergens and publishes periodic reports. We have previously reported on the association of race and ethnicity with the rates of positive responses to standard patch test allergens. This report extends those observations. The aim of the study was to report the North American Contact Dermatitis Group patch testing results from January 1, 1998, to December 31, 2006, comparing the frequency of positive reactions between white and black subjects. Standardized patch testing with 45 allergens was used at 13 centers in North America. χ analysis of results in black subjects as compared with whites was examined. A total of 19,457 patients were tested; 92.9% (17,803) were white and 7.1% (1,360) were black. The final diagnoses of ACD (whites, 45.9%; blacks, 43.6%) and irritant contact dermatitis (13.0%/13.3%) were similar in the 2 groups. The diagnosis of atopic dermatitis was less common in the white patients (8.9%) as compared with the black patients (13.3%). Positive patch test reactions rates were similar for most allergens. However, statistically, blacks reacted more frequently to p-phenylenediamine (7.0% vs 4.4%, P < 0.001), bacitracin (11.6% vs 8.3%, P = 0.0004), as well as specific rubber accelerators mercaptobenzothiazole (2.7% vs 1.8%), thiuram (6.2% vs 4.3%), and mercapto mix (1.9% vs 0.8%, P < 0.001). Whites had an increase in positive reactions to fragrances (12.12% vs 6.77%, P < 0.0001), formaldehyde (9.25% vs 5.45%, P < 0.0001), and some formaldehyde releaser preservatives used in personal care products and textile resins (9.80% vs 6.18%, P < 0.0001). There were statistically different rates of positive patch test reactions to specific allergens between black and white patients suspected of having ACD. The etiology of these differences is unclear but probably relates to culturally determined exposure patterns rather than genetic differences.

Resource concentration hypothesis: effect of host plant patch size on density of herbivorous insects.

PubMed

Grez, A A; González, R H

1995-09-01

The resource concentration hypothesis (Root 1973) predicts that specialist herbivorous insects should be more abundant in large patches of host plants, because the insects are more likely to find and stay longer in those patches. Between August 1989 and January 1990 we experimentally tested Root's hypothesis by analyzing the numerical response of four species of herbivorous insects associated with patches of 4, 16, 64 and 225 cabbage plants, Brassica oleracea var. capitata. In addition, we studied the colonization of patches by adults of Plutella xylostella (L.) (Lepidoptera: Plutellidae), and the migration of their larvae in patches of different sizes. No herbivorous insect densities differed significantly with patch size. Adults of P. xylostella colonized all kind of patches equally. Larvae did not migrate between patches, and their disappearance rate did not differ between patches. The resource concentration hypothesis is organism-dependent, being a function of the adult and juvenile herbivore dispersal behavior in relation to the spatial scale of patchiness.

Comparison of three different techniques for application of water solutions to Finn Chambers®.

PubMed

Frick-Engfeldt, Malin; Gruvberger, Birgitta; Isaksson, Marléne; Hauksson, Inese; Pontén, Ann; Bruze, Magnus

2010-11-01

With regard to contact allergy, the dose of a sensitizer per unit skin area is an important factor for both sensitization and elicitation, and therefore a known amount/volume of test preparation should be applied at patch testing. To compare three different techniques for the application of aqueous solutions to Finn Chambers, in order to determine the precision and accuracy of each technique when the recommended 15 µl volume is applied. Four technicians applied formaldehyde 1.0% aq. (wt/vol) and methylchloroisothiazolinone/methylisothiazolinone 200 ppm (wt/vol) in sets of 10 onto Finn Chambers, with three different techniques: (i) micro-pipetting; (ii) dripping the solutions; and (iii) dripping the solutions followed by removal of excess solution with a soft tissue. Assessment of the variations was performed with the use of descriptive data. The ability to apply the exact amount was assessed by Fisher's exact test by categorizing each application as in or out of the range 12-18 µl. The micro-pipette technique had the best accuracy and precision, as well as the lowest inter-individual variation. The technique in which excess solution was removed had good precision, but failed in the application of the defined amount, i.e. 15 µl. © 2010 John Wiley & Sons A/S.

Additive value of patch testing custom epoxy materials from the workplace at the occupational disease specialty clinic in Toronto.

PubMed

Houle, Marie-Claude; Holness, D Linn; Dekoven, Joel; Skotnicki, Sandy

2012-01-01

Allergic contact dermatitis (ACD) to epoxy resins is one of the major causes of occupationally induced ACD. Testing of custom epoxy materials from the workplace is often performed to diagnose ACD. The objective of this study was to investigate the additive value of patch testing custom-made epoxy materials. We retrospectively analyzed outcomes of 24 patients who were tested to custom epoxy resin materials between January 2002 and July 2011. For 11 patients (46%), the testing of their materials from work had no additional value (negative results). For 13 patients (54%), there was an additional value of testing custom allergens. Of those, 7 patients (54%) had positive reactions to custom epoxy materials that reinforced the test results found with the commercially available allergens, and 6 (46%) patients had positive reactions only to custom epoxy materials. Therefore, for 6 patients (25%), there was a definite additive value of testing custom epoxy materials because the allergy was discovered with custom testing and not with the commercially available allergens. Because of the high percentage (54%) of patients with additive value of patch testing custom epoxy materials, we think that the inclusion of actual workplace epoxy materials should be strongly considered when patch testing patients with occupational epoxy exposure.

Constituents of smoke from cigarettes made from diverted nicotine replacement therapy patches.

PubMed

Morrissey, Hana; Ball, Patrick; Boland, Martin; Hefler, Marita; Thomas, David P

2016-03-01

Anecdotes of nicotine replacement therapy patch misuse associated with the introduction of smoke-free prisons have been reported by media internationally, including Canada in 2006, New Zealand in 2011 and Australia in 2014. This study identifies chemical compounds released through diverted nicotine replacement therapy patches when they are smoked. Two samples were produced: (i) shredded 21 mg nicotine replacement therapy patches rolled with tea leaves into a cigarette; and (ii) patches boiled in water and tea leaves, and then dried tea leaves rolled into a cigarette. The smoke was tested for nicotine, caffeine and toxins. High-performance liquid chromatography, mass spectrometry and spectrophotometry were used to detect the presence and quantity of nicotine and caffeine. A specialised laboratory was contracted to test the presence of toxins. Nicotine was liberated when the two samples were burnt but not if the nicotine replacement therapy patches were boiled in water alone. High concentrations of formaldehyde, acetaldehyde, acrolein, toluene, xylene and heavy metals were also released. Nicotine is released when diverted nicotine replacement therapy patches are smoked, as are caffeine and harmful toxins. These toxins have the potential to cause short- and long-term health damage. © 2015 Australasian Professional Society on Alcohol and other Drugs.

"Phase capture" in amblyopia: the influence function for sampled shape.

PubMed

Levi, Dennis M; Li, Roger W; Klein, Stanley A

2005-06-01

This study was concerned with what stimulus information humans with amblyopia use to judge the shape of simple objects. We used a string of four Gabor patches to define a contour. A fifth, center patch served as the test pattern. The observers' task was to judge the location of the test pattern relative to the contour. The contour was either a straight line, or an arc with positive or negative curvature. We asked whether phase shifts in the inner or outer pairs of patches distributed along the contour influence the perceived shape. That is, we measured the phase shift influence function. Our results, consistent with previous studies, show that amblyopes are imprecise in shape discrimination, showing elevated thresholds for both lines and curves. We found that amblyopes often make much larger perceptual errors (biases) than do normal observers in the absence of phase shifts. These errors tend to be largest for curved shapes and at large separations. In normal observers, shifting the phase of inner patches of the string by 0.25 cycle results in almost complete phase capture (attraction) at the smallest separation (2 lambda), and the capture effect falls off rapidly with separation. A 0.25 cycle shift of the outer pair of patches has a much smaller effect, in the opposite direction (repulsion). While several amblyopic observers showed reduced capture by the phase of the inner patches, to our surprise, several of the amblyopes were sensitive to the phase of the outer patches. We used linear multiple regression to determine the weights of all cues to the task: the carrier phase of the inner patches, carrier phase of the outer patches and the envelope of the outer patches. Compared to normal observers, some amblyopes show a weaker influence of the phase of the inner patches, and a stronger influence of both the phase and envelope of the outer patches. We speculate that this may be a consequence of abnormal "crowding" of the inner patches by the outer ones.

The fragrance hand immersion study - an experimental model simulating real-life exposure for allergic contact dermatitis on the hands.

PubMed

Heydorn, S; Menné, T; Andersen, K E; Bruze, M; Svedman, C; Basketter, D; Johansen, J D

2003-06-01

Recently, we showed that 10 x 2% of consecutively patch-tested hand eczema patients had a positive patch test to a selection of fragrances containing fragrances relevant to hand exposure. In this study, we used repeated skin exposure to a patch test-positive fragrance allergen in patients previously diagnosed with hand eczema to explore whether immersion of fingers in a solution with or without the patch-test-positive fragrance allergen would cause or exacerbate hand eczema on the exposed finger. The study was double blinded and randomized. All participants had a positive patch test to either hydroxycitronellal or Lyral (hydroxyisohexyl 3-cyclohexene carboxaldehyde). Each participant immersed a finger from each hand, once a day, in a solution containing the fragrance allergen or placebo. During the first 2 weeks, the concentration of fragrance allergen in the solution was low (approximately 10 p.p.m.), whilst during the following 2 weeks, the concentration was relatively high (approximately 250 p.p.m.), imitating real-life exposure to a household product like dishwashing liquid diluted in water and the undiluted product, respectively. Evaluation was made using a clinical scale and laser Doppler flow meter. 3 of 15 hand eczema patients developed eczema on the finger immersed in the fragrance-containing solution, 3 of 15 on the placebo finger and 3 of 15 on both fingers. Using this experimental exposure model simulating real-life exposure, we found no association between immersion of a finger in a solution containing fragrance and development of clinically visible eczema on the finger in 15 participants previously diagnosed with hand eczema and with a positive patch test to the fragrance in question.

A hydrogel pericardial patch.

PubMed

Allder, M A; Guilbeau, E J; Brandon, T A; Walker, A S; Koeneman, J B; Fisk, R L

1990-01-01

Patients undergoing repeat cardiac operations are higher operative risks than those undergoing an initial cardiac procedure because adhesion formation can occur if the native pericardium is not closed. A unique composite patch that may be used to augment the pericardial tissue when primary closure is not possible has been developed. The patch is made of a hydrogel, poly (2-hydroxyethyl methacrylate), reinforced with an ethylene tetrafluoroethylene (ETFE) mesh. The mesh provides the needed mechanical properties, whereas the patch's surface properties are comparable to the hydrogel. Two types of patches were fabricated: one with the mesh weave at a perpendicular orientation and one at 45 degrees to the principle loading direction. The patches were mechanically tested and compared with canine pericardium. Ultimate tensile strength of the patches is not significantly different from canine pericardium (p less than 0.05), are the patch suture strength is nearly twice that of canine pericardium. The perpendicular patch is stiffer than canine pericardium, whereas the 45 degree patch is not (p less than 0.05). The 45 degree patch shows considerable promise as a pericardial substitute because it closely matches the properties native canine pericardium.

UV-cured adhesives for carbon fiber composite applications

NASA Astrophysics Data System (ADS)

Lu, Hsiao-Chun

Carbon fiber composite materials are increasingly used in automobile, marine, and aerospace industries due to their unique properties, including high strength, high stiffness and low weight. However, due to their brittle characteristic, these structures are prone to physical damage, such as a bird strike or impact damage. Once the structure is damaged, it is important to have fast and reliable temporary repair until the permanent repair or replacement can take place. In this dissertation, UV-based adhesives were used to provide a bonding strength for temporary repair. Adhesively bonded patch repair is an efficient and effective method for temporary repair. In this study, precured patches (hard patches) and dry fabric patches with laminating resins (soft patches) were performed. UV-based epoxy adhesives were applied to both patch repair systems. For precured patch repair, the bonding strengths were investigated under different surface treatments for bonding area and different adhesives thicknesses. The shear stresses of different UV exposure times and curing times were tested. Besides, the large patch repair was investigated as well. For soft patch repair, the hand wet lay-up was applied due to high viscosity of UV resins. A modified single lap shear testing (ASTM D5868) was applied to determine the shear stress. The large patches used fiber glass instead of carbon fiber to prove the possibility of repair with UV epoxy resin by hand wet lay-up process. The hand lay-up procedure was applied and assisted by vacuum pressure to eliminate the air bubbles and consolidate the patches. To enhance the bonding strength and effective soft patch repair, vacuum assisted resin transferring molding (VaRTM) is the better option. However, only low viscosity resins can be operated by VaRTM. Hence, new UV-based adhesives were formulated. The new UV-based adhesives included photoinitiator (PI), epoxy and different solvents. Solvents were used to compound the photoinitiator into epoxy monomer. Acetone, tetrahydrofuran (THF) and chloroform were used as well as their anhydrous solvents. The UV exposure times and curing times of new UV-based resins were tested. FT-IR, DSC and DMA were used to investigate structure, glass transition temperatures(Tg) and properties of polymer. In summary, the UV-based adhesive was applied to adhesively bonded hard patch and soft patch repair. In addition, new UV-based resins were formulated for the VaRTM process. The in-field repair can be effective and efficient by using UV adhesives.

Ex-vivoand in-vitro assessment of mucoadhesive patches containing the gel-forming polysaccharide psyllium for buccal delivery of chlorhexidine base.

PubMed

Cavallari, Cristina; Brigidi, Patrizia; Fini, Adamo

2015-12-30

The aim of the present study was to evaluate the gel-forming polysaccharide psyllium in the preparation of mucoadhesive patches for the controlled release of chlorhexidine (CHX) to treat pathologies in the oral cavity, using the casting-solvent evaporation technique. A number of different film-forming semi-synthetic polymers, such as sodium carboxymethyl cellulose (SCMC) and hydroxypropylmethyl cellulose (HPMC) were evaluated for comparison. The patch formulations were characterized in terms of drug content, morphology surface, swelling and mucoadhesive properties, microbiology inhibition assay and in vitro release tests. Three ex-vivo testswere carried out using porcine mucosa: an alternative dissolution test using artificial saliva that allows contemporary measurement of dissolution and mucoadhesion, a permeation test through the mucosa and the measurement of mucoadhesion using a Nouy tensile tester, as the maximum force required for the separation of the patch from the mucosa surface. The patches were also examined for determination of the minimum inhibitory concentration in cultures of Escherichia coli and Staphylococcus aureus. All the patches incorporating psyllium were found suitable in terms of external morphology, mucoadhesion and controlled release of the drug: in the presence of psyllium the drug displays prolonged zero-order release related to slower swelling rate of the system. Copyright © 2015. Published by Elsevier B.V.

Patch testing in non-immediate cutaneous adverse drug reactions: value of extemporaneous patch tests.

PubMed

Assier, Haudrey; Valeyrie-Allanore, Laurence; Gener, Gwendeline; Verlinde Carvalh, Muriel; Chosidow, Olivier; Wolkenstein, Pierre

2017-11-01

Patch testing following a standardized protocol is reliable for identifying the culprit drug in cutaneous adverse drug reactions (CADRs). However, these patch tests (PTs) require pharmaceutical material and staff, which are not always easily available. To evaluate an extemporaneous PT method in CADRs. We retrospectively analysed data for all patients referred to our department between March 2009 and June 2013 for patch testing after a non-immediate CADR. The patients who supplied their own suspected drugs were tested both with extemporaneous PTs and with conventional PTs. Extemporaneous PTs involved a nurse crushing and diluting the drug in pet. in a ratio of approximately one-third to two-thirds. Standardized PTs were performed according to guidelines, with commercial drugs diluted to 30% or with active ingredients diluted to 10%. We analysed the data for the two PT methods in terms of the number of positive test reactions, drugs tested, and type of CADR for patients in whom the two PT methods were used. In total, 75 of 156 patients underwent the two PT procedures, including 91 double tests. Overall, 21 tests gave positive reactions with the two methods, and 69 other tests gave negative results with the two methods. Our series yielded results similar to those of published series concerning the types of CADR and the drugs responsible. Our results suggest that, for CADRs, if a patient supplies a suspected drug but if the pharmaceutical material and staff are not available for conventional PTs, extemporaneous PTs performed by the nurse with the commercial drug used by the patient can be useful and reliable. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contact Allergy to Hydroperoxides of Linalool and D-Limonene in a US Population.

PubMed

Nath, Neel Som; Liu, Beiyu; Green, Cynthia; Atwater, Amber Reck

Linalool and D-limonene are common fragrance ingredients that readily oxidize on exposure to air. The resulting hydroperoxides of linalool and D-limonene have been shown to have high frequencies of positive patch test reactions in several European and international studies. The aim of the study was to investigate the prevalence of contact allergy to the hydroperoxides of linalool and D-limonene in a US population. In this retrospective study, 103 patients with suspected fragrance allergy were patch tested to linalool 10% petrolatum (pet), hydroperoxides of linalool 1% pet, D-limonene 10% pet, and/or the hydroperoxides of D-limonene 0.3% pet between July 9, 2014, and October 25, 2016. In this study, the frequency of positive patch test reactions to the hydroperoxides of linalool is 20% (19/96), and the frequency of positive reactions to the hydroperoxides of D-limonene is 8% (7/90). These high frequencies suggest that patch testing to the hydroperoxides of linalool and limonene should be performed in all patients with suspected fragrance allergy.

Adenosine-loaded dissolving microneedle patches to improve skin wrinkles, dermal density, elasticity and hydration.

PubMed

Kang, G; Tu, T N T; Kim, S; Yang, H; Jang, M; Jo, D; Ryu, J; Baek, J; Jung, H

2018-04-01

Although dissolving microneedle patches have been widely studied in the cosmetics field, no comparisons have been drawn with the topical applications available for routine use. In this study, two wrinkle-improving products, adenosine-loaded dissolving microneedle patches and an adenosine cream, were evaluated for efficacy, with respect to skin wrinkling, dermal density, elasticity, and hydration, and safety in a clinical test on the crow's feet area. Clinical efficacy and safety tests were performed for 10 weeks on 22 female subjects with wrinkles around their eyes. The adenosine-loaded dissolving microneedle patch was applied once every 3 days, in the evening, for 8 weeks to the designated crow's feet area. The adenosine cream was applied two times per day, in the morning and evening, for 8 weeks to the other crow's feet area. Skin wrinkling, dermal density, elasticity, and hydration were measured by using PRIMOS ® premium, Dermascan ® C, Cutometer ® MPA580, and Corneometer ® CM 825, respectively. In addition, subjective skin irritation was evaluated by self-observation, and objective skin irritation was assessed through expert interviews. The adenosine-loaded dissolving microneedle patches had a similar or better efficacy than the adenosine cream. Both groups showed statistically significant efficacy for almost all parameters (P < 0.05). The dissolving microneedle patches had a long-lasting effect on the average wrinkle depth (P < 0.05), only showed efficacy in dermal density (P < 0.05), had an early improving effect on elasticity (P < 0.05), and demonstrated better hydration efficacy (P < 0.001). No adverse effects were observed in either group during the test period. In the clinical efficacy test of four skin-improvement parameters, adenosine-loaded dissolving microneedle patches showed the same or better effect than the adenosine cream, although the weekly adenosine dose was 140 times lower. The dissolving microneedle patches caused no adverse reactions. These adenosine-loaded dissolving microneedle patches are expected to be safe, effective, and novel cosmetics for skin improvement. © 2018 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Volatility of fragrance chemicals: patch testing implications.

PubMed

Gilpin, Sarah J; Hui, Xiaoying; Maibach, Howard I

2009-01-01

Diagnostic and predictive patch testing to determine contact allergy due to fragrance materials requires applying a fixed dose of material to the skin. This dose can be affected by the volatile nature of fragrances; little data exist on how the loss of fragrance dose due to volatility affects patch testing. (1) To evaluate pH dependence and evaporation rates of two fragrance chemicals, geraniol, citronellol, and a common fragrance solvent, diethyl phthalate (DEP) and (2) Assess implications for predictive patch-testing methods for fragrances. pH analysis of each material at 1% for three values (4.0, 5.0, 7.0) was done over 40 hours. Volatility experiments for each material, nonradiolabeled and radiolabeled, were conducted over a 24-hour period, taking readings at six time points (5 minutes, 15 minutes, 40 minutes, 1 hour, 3 hours, and 24 hours). Evaporation rates were not sensitive to pH shifts from 4.0 to 7.0. Evaporation rates for nonradiolabeled materials were low: after 24 hours, geraniol lost 8.9%, citronellol 27.0% and DEP 14.5%. The volatility data for radiolabeled materials demonstrated that geraniol loses up to 39% of its dose, citronellol loses up to 26%, and DEP up to 14% within 40 minutes. The tendency of fragrance materials to evaporate can impact the dose being applied to the patch and therefore the result of the patch and ultimately the decision-making process regarding that fragrance material's safety. These data, developed with DEP, utilized in a predictive sensitization assay cannot be generalized.

Two plus blue equals green: Grapheme-color synesthesia allows cognitive access to numerical information via color

PubMed Central

McCarthy, J. Daniel; Barnes, Lianne N.; Alvarez, Bryan D.; Caplovitz, Gideon Paul

2013-01-01

In grapheme-color synesthesia, graphemes (e.g., numbers or letters) evoke color experiences. It is generally reported that the opposite is not true: colors will not generate experiences of graphemes or their associated information. However, recent research has provided evidence that colors can implicitly elicit symbolic representations of associated graphemes. Here, we examine if these representations can be cognitively accessed. Using a mathematical verification task replacing graphemes with color patches, we find that synesthetes can verify such problems with colors as accurately as with graphemes. Doing so, however, takes time: ~250ms per color. Moreover, we find minimal reaction time switch-costs for switching between computing with graphemes and colors. This demonstrates that given specific task demands, synesthetes can cognitively access numerical information elicited by physical colors, and they do so as accurately as with graphemes. We discuss these results in the context of possible cognitive strategies used to access the information. PMID:24100131

Our experiences with the use of atopy patch test in the diagnosis of cow's milk hypersensitivity.

PubMed

Pustisek, Nives; Jaklin-Kekez, Alemka; Frkanec, Ruza; Sikanić-Dugić, Nives; Misak, Zrinjka; Jadresin, Oleg; Kolacek, Sanja

2010-01-01

Atopy patch test has been recognized as a diagnostic tool for the verification of food allergies in infants and small children suffering from atopic dermatitis. The test also has a role in the diagnosis of food allergies characterized by clinical signs associated with the digestive system. Yet, in spite of numerous studies, the test itself has hitherto not been standardized. Our study enlisted 151 children less than two years of age, who exhibited suspect skin and/or gastrointestinal manifestations of food allergy to cow's milk, and in whom tests failed to prove early type of allergic reaction. Atopy patch test was positive in 28% of the children with atopic dermatitis, 43% of the children with suspect gastrointestinal manifestation and 32% of the children with skin and gastrointestinal manifestations of food allergy. In our experience, atopy patch test is an excellent addition to the hitherto used tests for the diagnosis of food allergies. It targets specifically delayed type hypersensitivity reactions, which are difficult to confirm with other diagnostic tools. It is furthermore simple to perform, noninvasive and produces a minimum of undesired side effects. For these reasons, it should become part of the routine diagnostic toolset for food allergies to cow's milk in infants and children, and applied before a food challenge test.

Patch test reactions associated with sunscreen products and the importance of testing to an expanded series: retrospective analysis of North American Contact Dermatitis Group data, 2001 to 2010.

PubMed

Warshaw, Erin M; Wang, Michael Z; Maibach, Howard I; Belsito, Donald V; Zug, Kathryn A; Taylor, James S; Mathias, C G Toby; Sasseville, Denis; Zirwas, Matthew J; Fowler, Joseph F; DeKoven, Joel G; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Storrs, Frances J

2013-01-01

Both active and inactive ingredients in sunscreen may cause contact dermatitis. This study aimed to describe allergens associated with a sunscreen source. A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 2001 and 2010 was performed. Of 23,908 patients patch tested, 219 (0.9%) had sunscreen coded as an allergen source. Patients who were male, with occupational dermatitis, or older (older than 40 years) had significantly lower rates of allergic reactions to sunscreens; the most commonly affected areas were the face and exposed sites (P < 0.0001). The top 3 most frequent allergens in sunscreens were benzophenone-3 (70.2% for 10% concentration, 64.4% for 3% concentration), DL-alpha-tocopherol (4.8%), and fragrance mix I (4.0%). Less than 40% of positive patch test reactions were detected by the North American Contact Dermatitis Group screening series of 65 to 70 allergens. A supplemental antigen series is important in detecting allergy to sunscreens.

Monitoring cocaine use in substance-abuse-treatment patients by sweat and urine testing.

PubMed

Preston, K L; Huestis, M A; Wong, C J; Umbricht, A; Goldberger, B A; Cone, E J

1999-09-01

Sweat and urine specimens were collected from 44 methadone-maintenance patients to evaluate the use of sweat testing to monitor cocaine use. Paired sweat patches that were applied and removed weekly (on Tuesdays) were compared with 3-5 consecutive urine specimens collected Mondays, Wednesdays, and Fridays. All patches (N = 930) were extracted in 2.5 mL of solvent and analyzed by ELISA immunoassay (cutoff concentration 10 ng/mL); a subset of patches (N = 591) was also analyzed by gas chromatography-mass spectrometry (GC-MS) for cocaine, benzoylecgonine (BZE), and ecgonine methyl ester (EME) (cutoff concentration 5 ng/mL). Urine specimens were subjected to qualitative analysis by EMIT (cutoff 300 ng/mL) and subsets were analyzed by TDx (semiquantitative, LOD 30 ng/mL) and by GC-MS for cocaine (LOD 5 ng/mL). Results were evaluated to (1) determine the relative amounts of cocaine and its metabolites in sweat; (2) assess replicability in duplicate patches; (3) compare ELISA and GC-MS results for cocaine in sweat; and (4) compare the detection of cocaine use by sweat and urine testing. Cocaine was detected by GC-MS in 99% of ELISA-positive sweat patches; median concentrations of cocaine, BZE, and EME were 378, 78.7, and 74 ng/mL, respectively. Agreement in duplicate patches was approximately 90% by ELISA analysis. The sensitivity, specificity, and efficiency of sweat ELISA cocaine results as compared with sweat GC-MS results were 93.6%, 91.3%, and 93.2%, respectively. The sensitivity, specificity, and efficiency between ELISA sweat patch and EMIT urine results were 97.6%, 60.5%, and 77.7%, respectively. These results support the use of sweat patches for monitoring cocaine use, though further evaluation is needed.

The MOAHLFA index of irritant sodium lauryl sulfate reactions: first results of a multicentre study on routine sodium lauryl sulfate patch testing.

PubMed

Uter, Wolfgang; Geier, Johannes; Becker, Detlef; Brasch, Jochen; Löffler, Harald

2004-01-01

In a multicentre study of the German Contact Dermatitis Research Group, sodium lauryl sulfate (SLS) 0.25% and 0.5% aq. has been added to routine allergen patch tests to assess its properties as a convenient diagnostic indicator of individual susceptibility to irritation at the time of patch testing. Previous studies indicated that irritant SLS reactivity may be related to individual factors such as age and sex. As these factors are, in turn, among the important predictors of contact allergy to many allergens, e.g. summarized in the 'MOAHLFA index', the impact of the MOAHLFA factors on irritant SLS patch test reactivity, and thus a potential for confounding, was assessed in the 5971 participating patients. As a result of 2 logistic regression analyses with an irritant reaction to 0.25% and 0.5% SLS, respectively, as outcome, male sex was identified as a relatively weak but significant risk factor (OR 1.38), while age 40 years or older was an even weaker risk factor (OR 1.22 and 1.15, respectively). Upon detailed analysis, no clear age gradient could, however, be identified. 1-day exposure time almost halved the odds of an irritant SLS reaction. In conclusion, this type of SLS patch test can be regarded as robust, indicating individual irritability relatively independent from the individual factors analysed here.

Occupationally related contact dermatitis in North American food service workers referred for patch testing, 1994 to 2010.

PubMed

Warshaw, Erin M; Kwon, Gina P; Mathias, C G Toby; Maibach, Howard I; Fowler, Joseph F; Belsito, Donald V; Sasseville, Denis; Zug, Kathryn A; Taylor, James S; Fransway, Anthony F; Deleo, Vincent A; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Zirwas, Matthew J; Dekoven, Joel G

2013-01-01

Contact dermatoses are common in food service workers (FSWs). This study aims to (1) determine the prevalence of occupationally related contact dermatitis among FSWs patch tested by the North American Contact Dermatitis Group (NACDG) and (2) characterize responsible allergens and irritants as well as sources. Cross-sectional analysis of patients patch tested by the NACDG, 1994 to 2010, was conducted. Of 35,872 patients patch tested, 1237 (3.4%) were FSWs. Occupationally related skin disease was significantly more common in FSWs when compared with employed non-FSWs. Food service workers were significantly more likely to have hand (P < 0.0001) and arm (P < 0.0006) involvement. The rates for irritant and allergic contact dermatitis in FSWs were 30.6% and 54.7%, respectively. Although the final diagnosis of irritant contact dermatitis was statistically higher in FSWs as compared with non-FSWs, allergic contact dermatitis was lower in FSWs as compared with non-FSWs. The most frequent currently relevant and occupationally related allergens were thiuram mix (32.5%) and carba mix (28.9%). Gloves were the most common source of responsible allergens. The NACDG standard tray missed at least 1 occupationally related allergen in 38 patients (4.3%). Among FSWs patch tested by the NACDG between 1994 and 2010, the most common allergens were thiuram mix and carba mix. Gloves were the most common source of responsible allergens.

Winter season, frequent hand washing, and irritant patch test reactions to detergents are associated with hand dermatitis in healthcare workers

PubMed Central

Callahan, Adrienne; Baron, Elma; Fekedulegn, Desta; Kashon, Michael; Yucesoy, Berran; Johnson, Victor J.; Santo Domingo, Diana; Kirkland, Brent; Luster, Michael I.; Nedorost, Susan

2013-01-01

Background Irritant hand dermatitis (IHD) is common in healthcare workers. Objective We studied endogenous irritant contact dermatitis threshold by patch testing, and exogenous factors such as season and hand washing for their association with IHD in healthcare workers. Methods Irritant patch testing with sodium lauryl sulfate (SLS), sodium hydroxide (NaOH) and benzalkonium chloride (BAK) at varying concentrations was measured in 113 healthcare workers. Examination for hand dermatitis occurred at one month intervals for a period of six months in the Midwestern US. Results Positive patch testing to low concentration SLS was associated with IHD (p=0.0310) after adjusting for age, gender, ethnicity, season, history of childhood flexural dermatitis, mean indoor relative humidity, glove and hand sanitizer usage). Subjects with a positive patch test to SLS were 78% more likely to have occurrence of IHD (IRR=1.78, 95% CI: 0.92, 3.45). Hand washing frequency (≥ 10 times a day; IRR=1.55, 95% CI: 1.01, 2.39) and cold season (IRR=2.76, 95% CI: 1.35, 5.65) were associated with IHD. No association was found between history of childhood flexural dermatitis and IHD in this population. Conclusions Both genetic and environmental factors are important in the etiology of IHD and should be considered in designing strategies to protect, educate and treat susceptible individuals. PMID:23857011

Frequency of positive patch test reactions to preservatives: The Australian experience.

PubMed

Chow, Elizabeth T; Avolio, Andrea M; Lee, Adriene; Nixon, Rosemary

2013-02-01

Preservatives are important causes of allergic contact dermatitis. The frequency of allergy to preservatives in Australia has been unknown to date. Our objectives are to report the frequency of positive preservative patch test reactions in Australia, comparing them to the published international data, as well as exploring the current regulations in place for preservative use in Australia. This was the first retrospective study of patch testing results, aggregated from four patch test clinics in three centres in Melbourne and Sydney. In all, 6845 patients were patch-tested during 1993-2006 and in this period the five most frequent preservative allergens were formaldehyde (4.6%), Euxyl K400 (containing methyldibromo glutaronitrile and phenoxyethanol) (3.3%), quaternium-15 (2.9%), diazolidinyl urea (2.4%), and methylchloroisothiazolinone/methylisothiazolinone (2.3%). These were followed by dimethylol dimethyl DMDM hydantoin (2.1%), chloroacetamide (2.1%) and imidazolidinyl urea (1.9%). The least frequent sensitisers were parabens (1.1%), 2-bromo-2-nitropropane-1, 3-diol (0.9%) and benzyl alcohol (0.4%). Formaldehyde was the most prevalent preservative allergen. Chloroacetamide allergy was more commonly seen in Australia. Parabens, 2-bromo-2-nitropropane-1,3-diol and benzyl alcohol were the least frequent sensitisers. Household products in Australia are not required to list all ingredients preventing sensitised individuals from properly assessing their exposure. © 2012 The Authors Australasian Journal of Dermatology © 2012 The Australasian College of Dermatologists.

Winter season, frequent hand washing, and irritant patch test reactions to detergents are associated with hand dermatitis in health care workers.

PubMed

Callahan, Adrienne; Baron, Elma; Fekedulegn, Desta; Kashon, Michael; Yucesoy, Berran; Johnson, Victor J; Domingo, Diana Santo; Kirkland, Brent; Luster, Michael I; Nedorost, Susan

2013-01-01

Irritant hand dermatitis (IHD) is common in health care workers. We studied endogenous irritant contact dermatitis threshold by patch testing and exogenous factors such as season and hand washing for their association with IHD in health care workers. Irritant patch testing with sodium lauryl sulfate (SLS), sodium hydroxide, and benzalkonium chloride at varying concentrations was measured in 113 health care workers. Examination for hand dermatitis occurred at 1-month intervals for a period of 6 months in the Midwestern United States. Positive patch testing to low-concentration SLS was associated with IHD (P = 0.0310) after adjusting for age, sex, ethnicity, season, history of childhood flexural dermatitis, mean indoor relative humidity, and glove and hand sanitizer usage. Subjects with a positive patch test to SLS were 78% more likely to have occurrence of IHD (incidence rate ratio [IRR] = 1.78; 95% confidence interval [CI], 0.92-3.45). Hand washing frequency (≥10 times a day; IRR = 1.55; 95% CI, 1.01-2.39) and cold season (IRR = 2.76; 95% CI, 1.35-5.65) were associated with IHD. No association was found between history of childhood flexural dermatitis and IHD in this population. Both genetic and environmental factors are important in the etiology of IHD and should be considered in designing strategies to protect, educate, and treat susceptible individuals.

Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities.

PubMed

Klaassen, Raymond H G; Nolet, Bart A; Bankert, Daniëlle

2006-09-01

We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (below ground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series of short (<1 m) intra-patch movements alternate with longer inter-patch movements (>1 m). Tuber biomass densities showed a positive spatial auto-correlation at a short distance (<3 m), but not at a larger distance (3-8 m). Based on the spatial pattern of the food distribution (which is assumed to be pre-harvest information for the swan) and the energy costs and benefits for different food densities at various distances, we calculated the optimal length of an inter-patch movement. A swan that moves to the patch with the highest gain rate was predicted to move to the adjacent patch (at 1 m) if the food density in the current patch had been high (>25 g/m2) and to a more distant patch (at 7-8 m) if the food density in the current patch had been low (<25 g/m2). This prediction was tested by measuring the response of swans to manipulated tuber densities. In accordance with our predictions, swans moved a long distance (>3 m) from a low-density patch and a short distance (<3 m) from a high-density patch. The quantitative agreement between prediction and observation was greater for swans feeding in pairs than for solitary swans. The result of this movement strategy is that swans visit high-density patches at a higher frequency than on offer and, consequently, achieve a 38% higher long-term gain rate. Swans also take advantage of spatial variance in food abundance by regulating the time in patches, staying longer and consuming more food from rich than from poor patches. We can conclude that the shape of the foraging path is a reflection of the spatial pattern in the distribution of tuber densities and can be understood from an optimal foraging perspective.

Habitat corridors function as both drift fences and movement conduits for dispersing flies.

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

Fried, Joanna H.; Levey Douglas J.; Hogsette, Jerome A.

2005-03-30

Abstract Corridors connect otherwise isolated habitat patches and can direct movement of animals among such patches. In eight experimental landscapes, we tested two hypotheses of how corridors might affect dispersal behavior. The Traditional Corridor hypothesis posits that animals preferentially leave patches via corridors, following them into adjacent patches. The Drift Fence hypothesis posits that animals dispersing through matrix habitat are diverted into patches with corridors because they follow corridors when encountered. House flies (Musca domestica L.), a species that prefers the habitat of our patches and corridors, were released in a central patch (100•100 m) and recaptured in peripheral patchesmore » that were or were not connected by a corridor. Flies were captured more frequently in connected than unconnected patches, thereby supporting the Traditional Corridor hypothesis. The Drift Fence hypothesis was also supported, as flies were captured more frequently in unconnected patches with blind (dead end) corridors than in unconnected patches of equal area without blind corridors. A second experiment tested whether these results might be dependent on the type of patch-matrix boundary encountered by dispersing flies and whether edge-following behavior might be the mechanism underlying the observed corridor effect in the first experiment. We recorded dispersal patterns of flies released along forest edges with dense undergrowth in the forest (‘‘closed’’ edges) and along edges with little forest understory (‘‘open’’ edges). Flies were less likely to cross and more likely to follow closed edges than open edges, indicating that when patch and corridor edges are pronounced, edge-following behavior of flies may direct them along corridors into connected patches. Because edges in the first experiment were open, these results also suggest that corridor effects for flies in that experiment would have been even stronger if the edges around the source patches and corridors had been more closed. Taken together, our results suggest that corridors can affect dispersal of organisms in unappreciated ways (i.e., as drift fences) and that edge type can alter dispersal behavior.« less

Scale-dependent feedbacks between patch size and plant reproduction in desert grassland

USGS Publications Warehouse

Svejcar, Lauren N.; Bestelmeyer, Brandon T.; Duniway, Michael C.; James, Darren K.

2015-01-01

Theoretical models suggest that scale-dependent feedbacks between plant reproductive success and plant patch size govern transitions from highly to sparsely vegetated states in drylands, yet there is scant empirical evidence for these mechanisms. Scale-dependent feedback models suggest that an optimal patch size exists for growth and reproduction of plants and that a threshold patch organization exists below which positive feedbacks between vegetation and resources can break down, leading to critical transitions. We examined the relationship between patch size and plant reproduction using an experiment in a Chihuahuan Desert grassland. We tested the hypothesis that reproductive effort and success of a dominant grass (Bouteloua eriopoda) would vary predictably with patch size. We found that focal plants in medium-sized patches featured higher rates of grass reproductive success than when plants occupied either large patch interiors or small patches. These patterns support the existence of scale-dependent feedbacks in Chihuahuan Desert grasslands and indicate an optimal patch size for reproductive effort and success in B. eriopoda. We discuss the implications of these results for detecting ecological thresholds in desert grasslands.

Reactivity to sorbitan sesquioleate affects reactivity to fragrance mix I.

PubMed

Geier, Johannes; Schnuch, Axel; Lessmann, Holger; Uter, Wolfgang

2015-11-01

Fragrance mix I (FM I) and its single constituents contain 5% and 1% sorbitan sesquioleate (SSO), respectively. SSO is a rare sensitizer and a potential irritant. To determine whether the outcome of the FM I breakdown test is affected by positive patch test reactivity to SSO. A retrospective analysis of data from the Information Network of Departments of Dermatology, 1998-2013, was performed. The full FM I breakdown test including SSO was tested in 2952 patients. Of these, 154 (5.2%) had a positive patch test reaction to SSO 20% pet. and 2709 (91.8%) had a negative patch test reaction. Positive reactions to one or more of the single fragrances contained in the mix were significantly more common (82.5% versus 57.3%) in SSO-positive patients, who also had more multiple reactions than FM I-positive patients with negative SSO reactions (61.5% versus 21.3% patients with reactions to two or more fragrances). Our results indicate that reactivity to SSO markedly affects the outcome of patch testing with FM I and its single constituents. SSO must be an obligatory part of the full FM I breakdown test, and should ideally be included in the baseline series. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Hydroxychloroquine-induced acute generalized exanthematous pustulosis with positive patch-testing.

PubMed

Charfi, Ons; Kastalli, Sarrah; Sahnoun, Rym; Lakhoua, Ghozlane

2015-01-01

Acute generalized exanthematous pustulosis (AGEP) is a severe cutaneous adverse reaction, mostly induced by drugs. Hydroxychloroquine have been rarely reported in literature as a causative drug of this reaction. We report a case of AGEP induced by hydroxychloroquine with systemic involvement and confirmed by positive patch testing.

Highway concrete pavement technology development and testing : volume III, field evaluation of Strategic Highway Research Program (SHRP) C-205 test sites (high-performance concrete).

DOT National Transportation Integrated Search

2006-05-01

This research study, sponsored by the Federal Highway Administration, summarizes the field performance of eight high-early-strength (HES) : concrete patches between 1994 and 1998. The patches were constructed under the Strategic Highway Research Prog...

The utility of patch tests using larger screening series of allergens.

PubMed

Larkin, A; Rietschel, R L

1998-09-01

The number of patch test allergens available within the United States for routine commercial purchase is limited. Allergens chosen for inclusion in routine screening series or patch test trays vary, and the degree of information obtained from any series may or may not serve a patient's needs. Knowledge of how well the allergens chosen for inclusion in the two commercially available sources perform compared with a more expansive panel of tests can help physicians select the more appropriate tests. From 1994 to mid-1997, 554 patients were tested with allergens recommended by the North American Contact Dermatitis Group (NACDG). This included all allergens currently available from both current domestic sources, although not in the identical form used by the Thin-layer Rapid Use Epicutaneous Test (TRUE) test (Glaxo Dermatology, Research Triangle Park, NC). Another 185 patients were tested with supplemental series of allergens. The larger the series of allergens used, the more positive tests were found and the more relevant tests as well. Hermal patch test allergens identified about 55% of the information found by the NACDG series; the TRUE test allergens (but not in the TRUE test system) identified 65%. Of the 103 reactions to supplemental allergens not found by the NACDG series, 59 were relevant. Larger series of allergens can enhance accurate diagnosis of allergic contact dermatitis. No single arbitrary series of allergens can adequately survey the contemporary environment of individual patients. Selection of allergens for testing requires consideration of the patient's history and access to appropriate environmental contactants.

Lidocaine 20% patch vs lidocaine 5% gel for topical anaesthesia of oral mucosa.

PubMed

Bågesund, Mats; Tabrizi, Parisa

2008-11-01

Topical anaesthetics are important to provide pain control at dental injection. The aim was to evaluate the effectiveness of the intraoral topical anaesthetics lidocaine 20% patch (DentiPatch) and lidocaine 5% gel. The randomized unblinded cross-over study included 31 patients (ten boys, 21 girls) aged 13.5 +/- 2.5 years. Application of lidocaine patch or gel was randomly used at first and second visit in the upper premolar region. Heart rate was measured before and at each needle insertion after 2.5, 5, and 15 min and at injection after 15 min. Discomfort and pain were expressed in visual analogue scales (VAS). Paired t-test and Mann-Whitney U-test were used for statistic analyses. Heart rate at buccal injection decreased more when the patch was used (P = 0.0149). Heart rate was lower at the second visit (P = 0.0287). Patients expressed less discomfort when the patch was used on both buccal (P = 0.0150) and palatal (P = 0.0391) site. Boys had lower heart rate and VAS pain scale ratings than girls. Good pain control can reduce the patients' anxiety level--expressed in heart rate--at the second appointment. The patch and gel seem to provide similar pain reduction at needle stick and injection of local anaesthetics.

Patch based predation in a southern Appalachian stream

Treesearch

C.A. Gibson; R.E. Ratajezak; G.D. Grossman

2004-01-01

Streams are characterized by high degrees of patchiness that could influence the role of predators in these systems. Here we assess the impact of predatory benthic fishes on benthic macroinvertebrate density, biomass, and community structure at the patch scale in a fourth order stream in the southern Appalachians. We tested the role of predation in two different patch...

Collagen-Based Fillers as Alternatives to Cyanoacrylate Glue for the Sealing of Large Corneal Perforations.

PubMed

Samarawickrama, Chameen; Samanta, Ayan; Liszka, Aneta; Fagerholm, Per; Buznyk, Oleksiy; Griffith, May; Allan, Bruce

2018-05-01

To describe the use of collagen-based alternatives to cyanoacrylate glue for the sealing of acute corneal perforations. A collagen analog comprising a collagen-like peptide conjugated to polyethylene glycol (CLP-PEG) and its chemical crosslinker were tested for biocompatibility. These CLP-PEG hydrogels, which are designed to act as a framework for corneal tissue regeneration, were then tested as potential fillers in ex vivo human corneas with surgically created full-thickness perforations. Bursting pressures were measured in each of 3 methods (n = 10 for each condition) of applying a seal: 1) cyanoacrylate glue with a polyethylene patch applied ab externo (gold standard); 2) a 100-μm thick collagen hydrogel patch applied ab interno, and 3) the same collagen hydrogel patch applied ab interno supplemented with CLP-PEG hydrogel molded in situ to fill the remaining corneal stromal defect. Cyanoacrylate gluing achieved a mean bursting pressure of 325.9 mm Hg, significantly higher than the ab interno patch alone (46.3 mm Hg) and the ab interno patch with the CLP-PEG filler (86.6 mm Hg). All experimental perforations were sealed effectively using 100 μm hydrogel sheets as an ab interno patch, whereas conventional ab externo patching with cyanoacrylate glue failed to provide a seal in 30% (3/10) cases. An ab interno patch system using CLP-PEG hydrogels designed to promote corneal tissue regeneration may be a viable alternative to conventional cyanoacrylate glue patching for the treatment of corneal perforation. Further experimentation and material refinement is required in advance of clinical trials.

Examination of the mechanism of action of two pre-quit pharmacotherapies for smoking cessation.

PubMed

Ferguson, Stuart G; Walters, Julia A E; Lu, Wenying; Wells, Gudrun P; Schüz, Natalie

2015-12-21

There is substantial scope for improvement in the current arsenal of smoking cessation methods and techniques: even when front-line cessation treatments are utilized, smokers are still more likely to fail than to succeed. Studies testing the incremental benefit of using nicotine patch for 1-4 weeks prior to quitting have shown pre-quit nicotine patch use produces a robust incremental improvement over standard post-quit patch treatment. The primary objective of the current study is to test the mechanism of action of two pre-quit smoking cessation medications-varenicline and nicotine patch-in order to learn how best to optimize these pre-quit treatments. The study is a three group, randomized, open-label controlled clinical trial. Participants (n = 216 interested quitters) will be randomized to receive standard patch treatment (10 weeks of patch starting from a designated quit day), pre-quit patch treatment (two weeks of patch treatment prior to a quit day, followed by 10 weeks post-quit treatment) or varenicline (starting two weeks prior to quit day followed by 10 weeks post-quit). Participants will use study-specific modified smart-phones to monitor their smoking, withdrawal symptoms, craving, mood and social situations in near real-time over four weeks; two weeks prior to an assigned quit date and two weeks after this date. Smoking and abstinence will be assessed at regular study visits and biochemically verified. Understanding how nicotine patches and varenicline influence abstinence may allow for better tailoring of these treatments to individual smokers. Australian New Zealand Clinical Trials Registry, ACTRN12614000329662 (Registered: 27 March 2014).

Testing metapopulation concepts: effects of patch characteristics and neighborhood occupancy on the dynamics of an endangered lagomorph

USGS Publications Warehouse

Eaton, Mitchell J.; Hughes, Phillip T.; Hines, James E.; Nichols, James D.

2014-01-01

Metapopulation ecology is a field that is richer in theory than in empirical results. Many existing empirical studies use an incidence function approach based on spatial patterns and key assumptions about extinction and colonization rates. Here we recast these assumptions as hypotheses to be tested using 18 years of historic detection survey data combined with four years of data from a new monitoring program for the Lower Keys marsh rabbit. We developed a new model to estimate probabilities of local extinction and colonization in the presence of nondetection, while accounting for estimated occupancy levels of neighboring patches. We used model selection to identify important drivers of population turnover and estimate the effective neighborhood size for this system. Several key relationships related to patch size and isolation that are often assumed in metapopulation models were supported: patch size was negatively related to the probability of extinction and positively related to colonization, and estimated occupancy of neighboring patches was positively related to colonization and negatively related to extinction probabilities. This latter relationship suggested the existence of rescue effects. In our study system, we inferred that coastal patches experienced higher probabilities of extinction and colonization than interior patches. Interior patches exhibited higher occupancy probabilities and may serve as refugia, permitting colonization of coastal patches following disturbances such as hurricanes and storm surges. Our modeling approach should be useful for incorporating neighbor occupancy into future metapopulation analyses and in dealing with other historic occupancy surveys that may not include the recommended levels of sampling replication.

Departure Mechanisms for Host Search on High-Density Patches by the Meteorus pulchricornis

PubMed Central

Sheng, Sheng; Feng, Sufang; Meng, Ling; Li, Baoping

2014-01-01

Abstract Less attention has been paid to the parasitoid–host system in which the host occurs in considerably high density with a hierarchical patch structure in studies on time allocation strategies of parasitoids. This study used the parasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) and the Oriental leafworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) as the parasitoids–host model system to investigate patch-leaving mechanisms as affected by the high-host density, hierarchical patch structure, and foraging behaviors on both former and current patches. The results showed that three out of eight covariates tested had significant effects on the patch-leaving tendency, including the host density, ovipositor insertion, and host rejection on the current patch. The parasitoid paid more visits to the patch with high-density hosts. While the patch with higher host densities decreased the leaving tendency, the spatial distribution of hosts examined had no effect on the leaving tendency. Both oviposition and host rejection decreased the patch-leaving tendency. The variables associated with the former patch, such as the host density and number of ovipositor insertions, however, did not have an effect on the leaving tendency. Our study suggested that M. pulchricornis females may use an incremental mechanism to exploit high-density patches to the fullest. PMID:25502040

An experimental test of matrix permeability and corridor use by an endemic understory bird.

PubMed

Castellón, Traci D; Sieving, Kathryn E

2006-02-01

Because of widespread habitat fragmentation, maintenance of landscape connectivity has become a major focus of conservation planning, but empirical tests of animal movement in fragmented landscapes remain scarce. We conducted a translocation experiment to test the relative permeability of three landscape elements (open habitat, shrubby secondary vegetation, and wooded corridors) to movement by the Chucao Tapaculo (Scelorchilus rubecula), a forest understory bird endemic to South American temperate rainforest. Forty-one radio-tagged subjects were translocated (individually) to three landscape treatments consisting of small release patches that were either entirely surrounded by open habitat (pasture), entirely surrounded by dense shrubs, or linked to other patches by wooded corridors that were otherwise surrounded by open matrix. The number of days subjects remained in release patches before dispersal (a measure of habitat resistance) was significantly longer for patches surrounded by open habitat than for patches adjoining corridors or surrounded by dense shrubs. These results indicate that open habitat significantly constrains Chucao dispersal, in accord with expectation, but dispersal occurs equally well through wooded corridors and shrub-dominated matrix. Thus, corridor protection or restoration and management of vegetation in the matrix (to encourage animal movement) may be equally feasible alternatives for maintaining connectivity.

Mechanical and Vibration Testing of Carbon Fiber Composite Material with Embedded Piezoelectric Sensors

NASA Technical Reports Server (NTRS)

Duffy, Kirsten P.; Lerch, Bradley A.; Wilmoth, Nathan G.; Kray, Nicholas; Gemeinhardt, Gregory

2012-01-01

Piezoelectric materials have been proposed as a means of decreasing turbomachinery blade vibration either through a passive damping scheme, or as part of an active vibration control system. For polymer matrix fiber composite (PMFC) blades, the piezoelectric elements could be embedded within the blade material, protecting the brittle piezoceramic material from the airflow and from debris. Before implementation of a piezoelectric element within a PMFC blade, the effect on PMFC mechanical properties needs to be understood. This study attempts to determine how the inclusion of a packaged piezoelectric patch affects the material properties of the PMFC. Composite specimens with embedded piezoelectric patches were tested in four-point bending, short beam shear, and flatwise tension configurations. Results show that the embedded piezoelectric material does decrease the strength of the composite material, especially in flatwise tension, attributable to failure at the interface or within the piezoelectric element itself. In addition, the sensing properties of the post-cured embedded piezoelectric materials were tested, and performed as expected. The piezoelectric materials include a non-flexible patch incorporating solid piezoceramic material, and two flexible patch types incorporating piezoelectric fibers. The piezoceramic material used in these patches was Navy Type-II PZT.

Allergic contact dermatitis from a nonbisphenol A epoxy in a graphite fiber reinforced epoxy laminate.

PubMed

Mathias, C G

1987-09-01

An employee of the Composites Division of an aircraft engine manufacturing firm developed dermatitis associated with the handling of a graphite fiber reinforced epoxy laminate (epoxy prepreg). Patch test investigation demonstrated that the responsible causal agent was the nonbisphenol A epoxy binder, 4-glycidyloxy-N, N-diglycidylaniline. A patch test with bisphenol A epoxy from a standard patch test screening series was negative. Subsequent interviews with employees of the Composites Division suggested that a relative lack of awareness of the cutaneous hazards of fiber reinforced epoxy laminates, compared with liquid epoxy resin systems, may be an important risk factor for allergic sensitization to these composite materials.

Melasma

MedlinePlus

... page, please enable JavaScript. Melasma are patches of dark skin that appear on areas of the face ... on the cheeks, forehead, nose, or upper lip. Dark patches are usually symmetrical. Exams and Tests Your ...

Patch testing: facts and controversies.

PubMed

Wolf, Ronni; Orion, Edith; Ruocco, Vincenzo; Baroni, Adone; Ruocco, Eleonora

2013-01-01

The German dermatologist, Josef Jadassohn (1863-1936), first presented the results of his innovative patch-testing technique in 1895. The safety and efficacy of this diagnostic tool has stood the test of time and is still the gold standard for the diagnosis of allergic contact dermatitis (ACD). Since its discovery, much effort has been put into standardization and optimization of allergens, vehicles, and concentrations of patch-test materials; in procedures of its application; and in reading and scoring of test reactions--all contributing to the development of an accurate, reliable, and safe test with a high reproducibility of its results. Even this seemingly carved-in-stone practice, which has been used for nearly 120 years, has been questioned and challenged, engendering debates, disagreements, and controversies, which show no signs of coming to an end. Almost every step of the procedure has provoked discussions and controversies: Copyright © 2013 Elsevier Inc. All rights reserved.

Three-dimensional spatial grouping affects estimates of the illuminant

NASA Astrophysics Data System (ADS)

Perkins, Kenneth R.; Schirillo, James A.

2003-12-01

The brightnesses (i.e., perceived luminance) of surfaces within a three-dimensional scene are contingent on both the luminances and the spatial arrangement of the surfaces. Observers viewed a CRT through a haploscope that presented simulated achromatic surfaces in three dimensions. They set a test patch to be ~33% more intense than a comparison patch to match the comparison patch in brightness, which is consistent with viewing a real scene with a simple lightning interpretation from which to estimate a different level of illumination in each depth plane. Randomly positioning each surface in either depth plane minimized any simple lighting interpretation, concomitantly reducing brightness differences to ~8.5%, although the immediate surrounds of the test and comparison patches continued to differ by a 5:1 luminance ratio.

Pattern of occupational allergic dermatitis in the Dermatology Clinic, Hospital Kuala Lumpur.

PubMed

Rohna, R; Ganesapillai, T; Salbiah, D; Zaiton, I

1999-03-01

A two years retrospective analysis of patients diagnosed as contact allergic dermatitis with positive patch test attending the Dermatology clinic was performed. Of the 346 patients with a positive patch test, 14% had occupational dermatitis. This condition affected mainly young and inexperienced workers. An inverse relationship was seen between age and prevalence of occupational allergic dermatitis. Allergic hand dermatitis was the commonest presentation in occupational allergic dermatitis. This was followed by dermatitis of the exposed skin (face, neck, hands and forearms). The common sensitising agents identified were rubber chemicals and nickel. The two main groups at risk were factory workers and medical personnel. The common allergens found in factory workers were epoxy resin, pewter, nickel and rubber chemicals. Exposure dermatitis occurred in patients working in the pewter industry. Two thirds of medical personnel with hand dermatitis were allergic to rubber gloves. One year follow up after patch testing showed that 19% of patients still suffered from chronic dermatitis. Dermatitis improved in 34% of patients. Forty-seven percent were cured and stopped attending the clinic after patch testing and adequate counselling.

Contact sensitivities in palmar plantar pustulosis (acropustulosis).

PubMed

Yiannias, J A; Winkelmann, R K; Connolly, S M

1998-09-01

Acropustulosis, or chronic palmar plantar pustulosis (PPP), is a phenomenon of recurrent sterile pustules, erythema, and scaling affecting the palms and soles. Its pathogenesis is unclear, and it is difficult to treat. The purpose of this study was to elucidate further the factors involved in causing PPP, thereby enhancing the ability to manage this disease. All cases of PPP seen at Mayo Clinic Scottsdale from 1987 to 1993 were reviewed. 21 patients with PPP were identified, 15 of whom had been patch tested. 9 of the 15 patients (60%) showed positive patch test results. Fragrance was the most common sensitivity, but nickel, formaldehyde, para-phenylenediamine, thiuram, neomycin, mercury, balsam of Peru, and cinnamic aldehyde sensitivities were demonstrated. Less important factors included atopy, fungal and bacterial infections, and irritation. Although the mechanism of this sterile pustulosis response does not depend solely on delayed hypersensitivity mechanisms, we believe that we have demonstrated such a large number of positive patch tests in this chronic pustular dermatosis that patch testing should be considered in the routine work-up of these patients.

Composite Structures Repair Development at Kennedy Space Center

NASA Technical Reports Server (NTRS)

Cox, Sarah B.

2015-01-01

This presentation discusses the development and results of composite patch repair perfromed at Kennedy Space Center. This includes impact damage, patch repair methods, nondestructive evaluation, and edgewise compression testing.

Hand dermatitis in auto mechanics and machinists.

PubMed

Donovan, Jeffrey C H; Kudla, Irena; Holness, D Linn

2007-09-01

Auto mechanics and machinists presenting with suspected allergic contact dermatitis (ACD) have traditionally been patch-tested with a standard screening tray and a specialty tray such as the Oil and Cooling Fluid Series. While this has proven useful for patch-testing the machinist, there is a need for the development of a more specific allergen testing tray for the auto mechanic. The objective of the study was to compare clinical features and patch-test results of auto mechanics and machinists with hand dermatitis to evaluate differences in allergen profiles. We performed a chart review of 33 auto mechanics and 24 machinists referred to our Occupational Contact Dermatitis Clinic from 2002 to 2005 for evaluation of hand dermatitis. With a panel of 84 allergens, 52 positive reactions were detected in 17 cases of ACD in mechanics. The profiles were different from the cases of ACD diagnosed in 10 of 24 machinists. Mechanics and machinists differ in the spectrum of occupational exposures. Patch testing with greater numbers of allergens likely identifies a larger proportion of mechanics with occupationally relevant ACD. Further study is needed to determine the most appropriate allergens to include in a clinically useful "mechanic's tray."

Patch test reactions to metal salts in patients with different types of dermatitis.

PubMed

Turčić, Petra; Marinović Kulišić, Sandra; Lipozenčić, Jasna

2013-01-01

Metal allergies can be a clinical problem, especially in atopic individuals. This study is unique and contributes with new knowledge in everyday life skin care of irritant and atopic dermatitis patients. The aim of the study was to determine the frequency of positive patch test reactions to metal contact allergens (potassium dichromate, cobalt chloride, nickel sulfate, white mercury precipitate) in patients diagnosed with allergic contact dermatitis, irritant contact dermatitis, and atopic dermatitis. Between 2007 and 2011, patch testing was performed in 2185 patients according to the International Contact Dermatitis Research Group technique. Study results showed statistically significant differences in patch test responses to 2 allergens, nickel sulfate (χ(2)=24.22; p<0.001) and cobalt chloride (χ(2)=22.72; p<0.001). Nickel sulfate was the most common allergen in allergic contact dermatitis and atopic dermatitis, while for irritant contact dermatitis the most common allergen was cobalt chloride. Among the 4 tested metal allergens, the most common and relevant was nickel sulfate (χ(2)=17.25; p<0.004), found in almost all study subjects. In conclusion, the increased awareness of allergens and their potential sources may help limit the use of these chemicals in consumer product manufacturing.

Contact allergy to corticosteroids and Malassezia furfur in seborrhoeic dermatitis patients.

PubMed

Ljubojevic, S; Lipozencic, J; Basta-Juzbasic, A

2011-06-01

Seborrhoeic dermatitis (SD) is a chronic skin disease, requiring long-term treatment, which might promote sensitization. Malassezia furfur (Mf) plays an important role in seborrhoeic dermatitis. Objectives  The aim of this study was to determine the frequency of contact sensitivity in SD patients. A total of 100 patients and 20 healthy controls (HC) were investigated: 50 suffering from SD with no previous local corticosteroid treatment (SDN), 50 SD patients treated with local corticosteroids (SDC). Mycological examination for Mf was performed. All patients were patch tested with the baseline standard, corticosteroid series, with 12 commercial corticosteroid preparations frequently used in Croatia; and also with Mf. Malassezia furfur was found in 44 (88%) SDN, 37 (74%) SDC, and in 4 (20%) HC; patch test reaction to Mf was positive in one SDN and in three SDC. Positive patch tests to standard allergens were observed in 17 (34%) SDN, 33 (66%) SDC and 2 (10%) HC. Patch tests to the corticosteroid series revealed positive reactions in 4 SDC and to commercial corticosteroids in seven patients, i.e. 2 SD and 5 SDC. Patch tests to the baseline series and to both individual corticosteroid and commercial corticosteroid preparations should be performed in SD patients with persistent dermatitis, as contact-allergic reactions may complicate their dermatitis. Sensitization to Mf was found to be infrequent. © 2010 The Authors. Journal of the European Academy of Dermatology and Venereology © 2010 European Academy of Dermatology and Venereology.

Non-allergic cutaneous reactions in airborne chemical sensitivity--a population based study.

PubMed

Berg, Nikolaj Drimer; Linneberg, Allan; Thyssen, Jacob Pontoppidan; Dirksen, Asger; Elberling, Jesper

2011-06-01

Multiple chemical sensitivity (MCS) is characterised by adverse effects due to exposure to low levels of chemical substances. The aetiology is unknown, but chemical related respiratory symptoms have been found associated with positive patch test. The purpose of this study was to investigate the relationship between cutaneous reactions from patch testing and self-reported severity of chemical sensitivity to common airborne chemicals. A total of 3460 individuals participating in a general health examination, Health 2006, were patch tested with allergens from the European standard series and screened for chemical sensitivity with a standardised questionnaire dividing the participants into four severity groups of chemical sensitivity. Both allergic and non-allergic cutaneous reactions--defined as irritative, follicular, or doubtful allergic reactions--were analysed in relationship with severity of chemical sensitivity. Associations were controlled for the possible confounding effects of sex, age, asthma, eczema, atopic dermatitis, psychological and social factors, and smoking habits. In unadjusted analyses we found associations between allergic and non-allergic cutaneous reactions on patch testing and the two most severe groups of self-reported sensitivity to airborne chemicals. When adjusting for confounding, associations were weakened, and only non-allergic cutaneous reactions were significantly associated with individuals most severely affected by inhalation of airborne chemicals (odds ratio = 2.5, p = 0.006). Our results suggest that individuals with self-reported chemical sensitivity show increased non-allergic cutaneous reactions based on day 2 readings of patch tests. Copyright © 2011 Elsevier GmbH. All rights reserved.

Two decades of p-phenylenediamine and toluene-2,5-diamine patch testing - focus on co-sensitizations in the European baseline series and cross-reactions with chemically related substances.

PubMed

Vogel, Tatiana A; Heijnen, Rakita W; Coenraads, Pieter-Jan; Schuttelaar, Marie-Louise A

2017-02-01

Cross-reactions and co-sensitizations are of great importance in understanding contact allergy and exposure sources. To investigate common cross-reactions and co-sensitizations in p-phenylenediamine (PPD)-sensitized and toluene-2,5-diamine (TDA)-sensitized individuals. From our patch test population, 8036 patients patch tested with the European baseline series were extracted. Readings had to be performed at least on day 3 according to ICDRG guidelines. Two hundred and fifty-one patients were sensitized to PPD and/or TDA; 231 patients were sensitized to PPD, and 109 to TDA. Significant differences were observed regarding the strengths of patch test reactions to PPD and number of cross-reactions. For TDA, a difference was found between all reaction strengths, except between + and ++ strengths. PPD-sensitized individuals were more likely to be sensitized to carba mix, cobalt chloride, colophonium, p-tert-butyl phenolformaldehyde resin, paraben mix, and methylisothiazolinone. TDA-sensitized individuals were more often sensitized to carba mix. Cross-reactivity was commonly found among individuals sensitized to PPD or TDA, and was strongly related to the strength of the patch test reaction. Regarding co-sensitizations, a frequently appearing or common exposure source could not be determined. However, modification of the allergen by, for example, the skin microbiota may have caused the formation of molecules that are, for the human immune system, indistinguishable from PPD. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

EFFECT OF HYDROPHILIC AND HYDROPHOBIC POLYMER ON IN VITRO DISSOLUTION AND PERMEATION OF BISOPROLOL FUMARATE THROUGH TRANSDERMAL PATCH.

PubMed

Shabbir, Maryam; Ali, Sajid; Raza, Moosa; Sharif, Ali; Akhtar, Furoan Muhammad; Manan, Abdul; Fazli, Ali Raza; Younas, Neelofar; Manzoor, Iqra

2017-01-01

A matrix transdermal patch of bisoprolol fumarate was formulated with different concentrations of Eudragit RS 100 and Methocel E5 with PEG 400 as plasticizer by solvent evaporation technique. Tween 80 was added to the optimized patch to evaluate the effect of permeation enhancer at different concentration through the excised rabbit's skin. The patches were analyzed for weight variation, drug content, swelling index, erosion studies, moisture content, moisture uptake, water vapor transmission rate (WVTR) and water vapor permeability (WVP). In vitro dissolution test was carried out in USP dissolution apparatus V to select the optimized formulation. In vitr skin permeation studies were done in Franz diffusion cell using rabbit skin as a model membrane. The cumulative drug release and flux were determined to compare the result of test patches with a control patch. The greatest enhancement ratio (ER) was obtained in F03-PE with 30% Tween 80. F03-PE seemed to follow zero order kinetics with super case II mechanism of drug release. Statistical ANOVA suggested that there was a significant difference in formulations, steady flux and cumulative permeation rate at different Tween 80 concentrations.

Slime moulds use heuristics based on within-patch experience to decide when to leave.

PubMed

Latty, Tanya; Beekman, Madeleine

2015-04-15

Animals foraging in patchy, non-renewing or slowly renewing environments must make decisions about how long to remain within a patch. Organisms can use heuristics ('rules of thumb') based on available information to decide when to leave the patch. Here, we investigated proximate patch-departure heuristics in two species of giant, brainless amoeba: the slime moulds Didymium bahiense and Physarum polycephalum. We explicitly tested the importance of information obtained through experience by eliminating chemosensory cues of patch quality. In P. polycephalum, patch departure was influenced by the consumption of high, and to a much lesser extent low, quality food items such that engulfing a food item increased patch-residency time. Physarum polycephalum also tended to forage for longer in darkened, 'safe' patches. In D. bahiense, engulfment of any food item increased patch residency irrespective of that food item's quality. Exposure to light had no effect on the patch-residency time of D. bahiense. Given that these organisms lack a brain, our results illustrate how the use of simple heuristics can give the impression that individuals make sophisticated foraging decisions. © 2015. Published by The Company of Biologists Ltd.

Ungulates rely less on visual cues, but more on adapting movement behaviour, when searching for forage.

PubMed

Venter, Jan A; Prins, Herbert H T; Mashanova, Alla; Slotow, Rob

2017-01-01

Finding suitable forage patches in a heterogeneous landscape, where patches change dynamically both spatially and temporally could be challenging to large herbivores, especially if they have no a priori knowledge of the location of the patches. We tested whether three large grazing herbivores with a variety of different traits improve their efficiency when foraging at a heterogeneous habitat patch scale by using visual cues to gain a priori knowledge about potential higher value foraging patches. For each species (zebra ( Equus burchelli ), red hartebeest ( Alcelaphus buselaphus subspecies camaa ) and eland ( Tragelaphus oryx )), we used step lengths and directionality of movement to infer whether they were using visual cues to find suitable forage patches at a habitat patch scale. Step lengths were significantly longer for all species when moving to non-visible patches than to visible patches, but all movements showed little directionality. Of the three species, zebra movements were the most directional. Red hartebeest had the shortest step lengths and zebra the longest. We conclude that these large grazing herbivores may not exclusively use visual cues when foraging at a habitat patch scale, but would rather adapt their movement behaviour, mainly step length, to the heterogeneity of the specific landscape.

Simultaneous patch testing with fragrance mix I, fragrance mix II and their ingredients in southern Sweden between 2009 and 2015.

PubMed

Mowitz, Martin; Svedman, Cecilia; Zimerson, Erik; Isaksson, Marléne; Pontén, Ann; Bruze, Magnus

2017-11-01

Fragrance mix I (FM I) and fragrance mix II (FM II) are included in the European baseline series as screening substances for fragrance contact allergy. To investigate the frequency of allergic reactions to FM I, FM II and their ingredients in consecutively patch tested patients. A retrospective analysis of data from 4430 patients patch tested between 2009 and 2015 was performed. Of the patients, 6.5% were FM I-positive and 3.2% were FM II-positive. Forty-five per cent of FM I-positive patients did not have positive reactions to FM I ingredients. Thirty-five per cent of those who were FM II-positive did not have positive reactions to FM II ingredients. Twenty-seven per cent of those with positive reactions to one or more of the FM I ingredients were FM I-negative, and 36% of those who had positive reactions to one or more of the FM II ingredients were FM II-negative. The allergens with the highest pick-up rates were Evernia prunastri (1.8%), cinnamal (1.3%), citral (1.2%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (1.2%). Significant differences were observed in the proportions of positive reactions to FM I, FM II, eugenol, isoeugenol, and farnesol when results from patch testing with materials from different suppliers were compared. There is a risk of missing fragrance contact allergy when testing with only the fragrance mixes is performed. The use of preparations from different suppliers may affect the patch test results. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multicenter study of preservative sensitivity in patients with suspected cosmetic contact dermatitis in Korea.

PubMed

Lee, Sang S; Hong, Dong K; Jeong, Nam J; Lee, Jeung H; Choi, Yun-Seok; Lee, Ai-Young; Lee, Cheol-Heon; Kim, Kea J; Park, Hae Y; Yang, Jun-Mo; Lee, Ga-Young; Lee, Joon; Eun, Hee C; Moon, Kee-Chan; Seo, Seong J; Hong, Chang K; Lee, Sang W; Choi, Hae Y; Lee, Jun Y

2012-08-01

As many new cosmetic products are introduced into the market, attention must be given to contact dermatitis, which is commonly caused by cosmetics. We investigate the prevalence of preservative allergy in 584 patients with suspected cosmetic contact dermatitis at 11 different hospitals. From January 2010 to March 2011, 584 patients at 11 hospital dermatology departments presented with cosmetic contact dermatitis symptoms. These patients were patch-tested for preservative allergens. An irritancy patch test performed on 30 control subjects using allergens of various concentrations showed high irritancy rates. Preservative hypersensitivity was detected in 41.1% of patients. Allergens with the highest positive test rates were benzalkonium chloride (12.1%), thimerosal (9.9%) and methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) (5.5%). Benzalkonium chloride and chlorphenesin had the highest irritancy rate based on an irritancy patch test performed using various concentrations. Seven of 30 normal subjects had a positive irritant patch reading with 0.1% benzalkonium chloride and eight of 30 normal subjects had a positive irritant patch reading at 4 days with 0.5% chlorphenesin in petrolatum. Although benzalkonium chloride was highly positive for skin reactions in our study, most reactions were probably irritation. MCI/MI and thimerosal showed highly positive allergy reactions in our study. The optimum concentration of chlorphenesin to avoid skin reactions is less than 0.5%. © 2012 Japanese Dermatological Association.

Rod-cone interaction in light adaptation

PubMed Central

Latch, M.; Lennie, P.

1977-01-01

1. The increment-threshold for a small test spot in the peripheral visual field was measured against backgrounds that were red or blue. 2. When the background was a large uniform field, threshold over most of the scotopic range depended exactly upon the background's effect upon rods. This confirms Flamant & Stiles (1948). But when the background was small, threshold was elevated more by a long wave-length than a short wave-length background equated for its effect on rods. 3. The influence of cones was explored in a further experiment. The scotopic increment-threshold was established for a short wave-length test spot on a large, short wave-length background. Then a steady red circular patch, conspicuous to cones, but below the increment-threshold for rod vision, was added to the background. When it was small, but not when it was large, this patch substantially raised the threshold for the test. 4. When a similar experiment was made using, instead of a red patch, a short wave-length one that was conspicuous in rod vision, threshold varied similarly with patch size. These results support the notion that the influence of small backgrounds arises in some size-selective mechanism that is indifferent to the receptor system in which visual signals originate. Two corollaries of this hypothesis were tested in further experiments. 5. A small patch was chosen so as to lift scotopic threshold substantially above its level on a uniform field. This threshold elevation persisted for minutes after extinction of the patch, but only when the patch was small. A large patch made bright enough to elevate threshold by as much as the small one gave rise to no corresponding after-effect. 6. Increment-thresholds for a small red test spot, detected through cones, followed the same course whether a large uniform background was long- or short wave-length. When the background was small, threshold upon the short wave-length one began to rise for much lower levels of background illumination, suggesting the influence of rods. This was confirmed by repeating the experiment after a strong bleach when the cones, but not rods, had fully recovered their sensitivity. Increment-thresholds upon small backgrounds of long or short wave-lengths then followed the same course. PMID:894602

Response to rivastigmine transdermal patch or memantine plus rivastigmine patch is affected by apolipoprotein E genotype in Alzheimer patients.

PubMed

Han, Hyun Jeong; Kim, Byeong C; Lee, Jun-Young; Ryu, Seung-Ho; Na, Hae Ri; Yoon, Soo Jin; Park, Hyun Young; Shin, Joon Hyun; Cho, Soo-Jin; Yi, Hyon-Ah; Choi, Mun Seong; Heo, Jae-Hyeok; Park, Kyung Won; Kim, Kwang K; Choi, Seong Hye

2012-01-01

The apolipoprotein E (APOE) genotype in response to pharmacological treatments in patients with Alzheimer's disease (AD) remains a matter of controversy. This analysis investigated the effect of the APOE genotype on the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine patch in patients with mild to moderate AD. Two hundred and six (n = 206) patients with probable AD and Mini-Mental State Examination (MMSE) scores of 10-20 were randomized to rivastigmine patch monotherapy or memantine plus rivastigmine patch for 24 weeks. Of the 206 patients with probable AD, 146 patients who consented to genetic testing for APOE were included and assessed for this subgroup study. There were no significant differences on MMSE, NPI, ADAS-cog, ADCS-ADL, CDR-SB, NPI and FAB between rivastigmine patch monotherapy and memantine plus rivastigmine patch according to the APOE genotype. However, patients with moderately severe AD (MMSE ≤15) who were APOE ε4 carriers showed higher responder rates on ADCS-ADL with memantine plus rivastigmine patch compared to rivastigmine patch monotherapy. Moderately severe AD patients with the APOE ε4 allele may respond more favorably to memantine plus rivastigmine patch than ε4 noncarriers. Copyright © 2012 S. Karger AG, Basel.

Group-living herbivores weigh up food availability and dominance status when making patch-joining decisions.

PubMed

Stears, Keenan; Kerley, Graham I H; Shrader, Adrian M

2014-01-01

Two key factors that influence the foraging behaviour of group-living herbivores are food availability and individual dominance status. Yet, how the combination of these factors influences the patch-joining decisions of individuals foraging within groups has scarcely been explored. To address this, we focused on the patch-joining decisions of group-living domestic goats (Capra hircus). When individuals were tested against the top four ranked goats of the herd, we found that at patches with low food availability they avoided these dominant patch-holders and only joined subordinates (i.e. costs outweighed benefits). However, as the amount of food increased, the avoidance of the top ranked individuals declined. Specifically, goats shifted and joined the patch of an individual one dominance rank higher than the previous dominant patch holder when the initial quantity of food in the new patch was twice that of the lower ranking individual's patch (i.e. benefits outweighed costs). In contrast, when individuals chose between patches held by dominant goats, other than the top four ranked goats, and subordinate individuals, we found that they equally joined the dominant and subordinate patch-holders. This joining was irrespective of the dominance gap, absolute rank of the dominant patch-holder, sex or food availability (i.e. benefits outweighed costs). Ultimately, our results highlight that herbivores weigh up the costs and benefits of both food availability and patch-holder dominance status when making patch-joining decisions. Furthermore, as the initial quantity of food increases, food availability becomes more important than dominance with regard to influencing patch-joining decisions.

An experimental test of the habitat-amount hypothesis for saproxylic beetles in a forested region.

PubMed

Seibold, Sebastian; Bässler, Claus; Brandl, Roland; Fahrig, Lenore; Förster, Bernhard; Heurich, Marco; Hothorn, Torsten; Scheipl, Fabian; Thorn, Simon; Müller, Jörg

2017-06-01

The habitat-amount hypothesis challenges traditional concepts that explain species richness within habitats, such as the habitat-patch hypothesis, where species number is a function of patch size and patch isolation. It posits that effects of patch size and patch isolation are driven by effects of sample area, and thus that the number of species at a site is basically a function of the total habitat amount surrounding this site. We tested the habitat-amount hypothesis for saproxylic beetles and their habitat of dead wood by using an experiment comprising 190 plots with manipulated patch sizes situated in a forested region with a high variation in habitat amount (i.e., density of dead trees in the surrounding landscape). Although dead wood is a spatio-temporally dynamic habitat, saproxylic insects have life cycles shorter than the time needed for habitat turnover and they closely track their resource. Patch size was manipulated by adding various amounts of downed dead wood to the plots (~800 m³ in total); dead trees in the surrounding landscape (~240 km 2 ) were identified using airborne laser scanning (light detection and ranging). Over 3 yr, 477 saproxylic species (101,416 individuals) were recorded. Considering 20-1,000 m radii around the patches, local landscapes were identified as having a radius of 40-120 m. Both patch size and habitat amount in the local landscapes independently affected species numbers without a significant interaction effect, hence refuting the island effect. Species accumulation curves relative to cumulative patch size were not consistent with either the habitat-patch hypothesis or the habitat-amount hypothesis: several small dead-wood patches held more species than a single large patch with an amount of dead wood equal to the sum of that of the small patches. Our results indicate that conservation of saproxylic beetles in forested regions should primarily focus on increasing the overall amount of dead wood without considering its spatial arrangement. This means dead wood should be added wherever possible including in local landscapes with low or high dead-wood amounts. For species that have disappeared from most forests owing to anthropogenic habitat degradation, this should, however, be complemented by specific conservation measures pursued within their extant distributional ranges. © 2017 by the Ecological Society of America.

Recommendation to include fragrance mix 2 and hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral) in the European baseline patch test series.

PubMed

Bruze, Magnus; Andersen, Klaus Ejner; Goossens, An

2008-03-01

The currently used fragrance mix in the European baseline patch test series (baseline series) fails to detect a substantial number of clinically relevant fragrance allergies. To investigate whether it is justified to include hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral) and fragrance mix 2 containing hydroxyisohexyl 3-cyclohexene carboxaldehyde, citral, farnesol, coumarin, citronellol, and alpha-hexyl cinnamal in the European baseline patch test series. Survey of the literature on reported frequencies of contact allergy and allergic contact dermatitis from fragrance mix 2 and hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral) as well as reported results of experimental provocation test. Fragrance mix 2 has been demonstrated to be a useful additional marker of fragrance allergy with contact allergy rates up to 5% when included in various national baseline patch test series. Of the fragrance substances present in fragrance mix 2, hydroxyisohexyl 3-cyclohexene carboxaldehyde is the most common sensitizer. Contact allergy rates between 1.5% and 3% have been reported for hydroxyisohexyl 3-cyclohexene carboxaldehyde in petrolatum (pet.) at 5% from various European centres when tested in consecutive dermatitis patients. From 2008, pet. preparations of fragrance mix 2 at 14% w/w (5.6 mg/cm(2)) and hydroxyisohexyl 3-cyclohexene carboxaldehyde at 5% w/w (2.0 mg/cm(2)) are recommended for inclusion in the baseline series. With the Finn Chamber technique, a dose of 20 mg pet. preparation is recommended. Whenever there is a positive reaction to fragrance mix 2, additional patch testing with the 6 ingredients, 5 if there are simultaneous positive reactions to hydroxyisohexyl 3-cyclohexene carboxaldehyde and fragrance mix 2, is recommended.

Rebound spiking in layer II medial entorhinal cortex stellate cells: Possible mechanism of grid cell function

PubMed Central

Shay, Christopher F.; Ferrante, Michele; Chapman, G. William; Hasselmo, Michael E.

2015-01-01

Rebound spiking properties of medial entorhinal cortex (mEC) stellate cells induced by inhibition may underlie their functional properties in awake behaving rats, including the temporal phase separation of distinct grid cells and differences in grid cell firing properties. We investigated rebound spiking properties using whole cell patch recording in entorhinal slices, holding cells near spiking threshold and delivering sinusoidal inputs, superimposed with realistic inhibitory synaptic inputs to test the capacity of cells to selectively respond to specific phases of inhibitory input. Stellate cells showed a specific phase range of hyperpolarizing inputs that elicited spiking, but non-stellate cells did not show phase specificity. In both cell types, the phase range of spiking output occurred between the peak and subsequent descending zero crossing of the sinusoid. The phases of inhibitory inputs that induced spikes shifted earlier as the baseline sinusoid frequency increased, while spiking output shifted to later phases. Increases in magnitude of the inhibitory inputs shifted the spiking output to earlier phases. Pharmacological blockade of h-current abolished the phase selectivity of hyperpolarizing inputs eliciting spikes. A network computational model using cells possessing similar rebound properties as found in vitro produces spatially periodic firing properties resembling grid cell firing when a simulated animal moves along a linear track. These results suggest that the ability of mEC stellate cells to fire rebound spikes in response to a specific range of phases of inhibition could support complex attractor dynamics that provide completion and separation to maintain spiking activity of specific grid cell populations. PMID:26385258

Methylisothiazolinone testing at 2000 ppm: a prevalent sensitizer for allergic contact dermatitis.

PubMed

Ham, Kaiya; Posso-De Los Rios, Claudia J; Gooderham, Melinda

2015-01-01

Methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) have been identified as potent allergens. The optimal MI concentration for patch testing for reaction to these agents has not yet been identified, but it has been suggested that testing MI at 2000 ppm may reduce false-negative reactions. The aim of this study was to report allergic reactions to MI and MCI/MI detected in a community dermatology practice setting in Ontario, Canada. The patch test records of patients with suspected allergic contact dermatitis seen between October 2007 and June 2014 were reviewed. We compared positive patch testing before and after December 2011 when a higher MI concentration was used (2000 ppm aqueous) in addition to the baseline series MCI/MI at 100 ppm. A total of 794 patient records were reviewed. There were 38 true-positive reactions to MI or MCI/MI. Of these 38 patients, 26 (68%) were female. We detected an overall increase in the rate of positive patch testing to MCI/MI, MI alone, or both from 3.13% to 7.45% when MI concentration was introduced at 2000 ppm aqueous. Occupational differences existed between sexes. The addition of MI at 2000 ppm to our screening series effectively increased the detection of MI-induced allergic contact dermatitis.

Stability of selected volatile contact allergens in different patch test chambers under different storage conditions.

PubMed

Mose, Kristian F; Andersen, Klaus E; Christensen, Lars Porskjaer

2012-04-01

Patch test preparations of volatile substances may evaporate during storage, thereby giving rise to reduced patch test concentrations. To investigate the stability of selected acrylates/methacrylates and fragrance allergens in three different test chambers under different storage conditions. Petrolatum samples of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxypropyl acrylate (2-HPA), cinnamal and eugenol in patch test concentrations were stored in three different test chambers (IQ chamber™, IQ Ultimate™, and Van der Bend® transport container) at room temperature and in a refrigerator. The samples were analysed in triplicate with high-performance liquid chromatography. The decrease in concentration was substantial for all five allergens under both storage conditions in IQ chamber™ and IQ Ultimate™, with the exception of 2-HEMA during storage in the refrigerator. For these two chamber systems, the contact allergen concentration dropped below the stability limit in the following order: MMA, cinnamal, 2-HPA, eugenol, and 2-HEMA. In the Van der Bend® transport container, the contact allergens exhibited acceptable stability under both storage conditions, whereas MMA and 2-HPA required cool storage for maintenance of the limit. The Van der Bend® transport container was the best device for storage of samples of volatile contact allergens. © 2012 John Wiley & Sons A/S.

Departure mechanisms for host search on high-density patches by the Meteorus pulchricornis.

PubMed

Sheng, Sheng; Feng, Sufang; Meng, Ling; Li, Baoping

2014-01-01

Less attention has been paid to the parasitoid-host system in which the host occurs in considerably high density with a hierarchical patch structure in studies on time allocation strategies of parasitoids. This study used the parasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) and the Oriental leafworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) as the parasitoids-host model system to investigate patch-leaving mechanisms as affected by the high-host density, hierarchical patch structure, and foraging behaviors on both former and current patches. The results showed that three out of eight covariates tested had significant effects on the patch-leaving tendency, including the host density, ovipositor insertion, and host rejection on the current patch. The parasitoid paid more visits to the patch with high-density hosts. While the patch with higher host densities decreased the leaving tendency, the spatial distribution of hosts examined had no effect on the leaving tendency. Both oviposition and host rejection decreased the patch-leaving tendency. The variables associated with the former patch, such as the host density and number of ovipositor insertions, however, did not have an effect on the leaving tendency. Our study suggested that M. pulchricornis females may use an incremental mechanism to exploit high-density patches to the fullest. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

Behavioral response races, predator-prey shell games, ecology of fear, and patch use of pumas and their ungulate prey.

PubMed

Laundré, John W

2010-10-01

The predator-prey shell game predicts random movement of prey across the landscape, whereas the behavioral response race and landscape of fear models predict that there should be a negative relationship between the spatial distribution of a predator and its behaviorally active prey. Additionally, prey have imperfect information on the whereabouts of their predator, which the predator should incorporate in its patch use strategy. I used a one-predator-one-prey system, puma (Puma concolor)-mule deer (Odocoileus hemionus) to test the following predictions regarding predator-prey distribution and patch use by the predator. (1) Pumas will spend more time in high prey risk/low prey use habitat types, while deer will spend their time in low-risk habitats. Pumas should (2) select large forage patches more often, (3) remain in large patches longer, and (4) revisit individual large patches more often than individual smaller ones. I tested these predictions with an extensive telemetry data set collected over 16 years in a study area of patchy forested habitat. When active, pumas spent significantly less time in open areas of low intrinsic predation risk than did deer. Pumas used large patches more than expected, revisited individual large patches significantly more often than smaller ones, and stayed significantly longer in larger patches than in smaller ones. The results supported the prediction of a negative relationship in the spatial distribution of a predator and its prey and indicated that the predator is incorporating the prey's imperfect information about its presence. These results indicate a behavioral complexity on the landscape scale that can have far-reaching impacts on predator-prey interactions.

Experiments on selection of feeding site and food size in oystercatchers, Haematopus ostralegus, of different social status

NASA Astrophysics Data System (ADS)

Leopold, M. F.; Swennen, C.; De Bruijn, L. L. M.

Oystercatchers, Haematopus ostralegus, were tested for size selection in two prey species, cockles ( Cerastoderma edule) and mussels ( Mytilus edulis), under semi-natural, but strictly experimental, conditions that allowed recovery of all shells of prey items eaten. Within any patch of cockles offered, size was not an important selection criterion for the birds. The mean length of cockles consumed always differed less than 1 mm (the measuring accuracy) from the mean length of the cockles presented. When given a choice between patches of different prey quality, the birds tended to select patches according to their relative dominance status, with the most dominant bird feeding mainly in the patch where the prey items had the largest flesh contents. Less dominant birds were forced out of the preferred patch and obtained most of theif food from a patch of presumedly lower quality. One of these birds adapted its prey-handling method and its bill shape for efficient feeding in such a low quality pathc, and it continued feeding in that patch, even after the dominant conspecifics had been removed. In experiments with mussels as prey, the test bird did not select primarily on the basis of size but tended to eat those mussels that were easiest to open. It is concluded that size selection in oystercatchers that eat either cockles or mussels ends with the choice of a certain foraging patch. Within a patch of cockles of one year-class, which is the field condition for the majority of oystercatchers in the Wadden Sea, no selection for size occurs, because this would take too much extra searching time to be profitable.

A large-scale deforestation experiment: Effects of patch area and isolation on Amazon birds

USGS Publications Warehouse

Ferraz, G.; Nichols, J.D.; Hines, J.E.; Stouffer, P.C.; Bierregaard, R.O.; Lovejoy, T.E.

2007-01-01

As compared with extensive contiguous areas, small isolated habitat patches lack many species. Some species disappear after isolation; others are rarely found in any small patch, regardless of isolation. We used a 13-year data set of bird captures from a large landscape-manipulation experiment in a Brazilian Amazon forest to model the extinction-colonization dynamics of 55 species and tested basic predictions of island biogeography and metapopulation theory. From our models, we derived two metrics of species vulnerability to changes in isolation and patch area. We found a strong effect of area and a variable effect of isolation on the predicted patch occupancy by birds.

Cannabis Use Surveillance by Sweat Analysis.

PubMed

Gambelunghe, Cristiana; Fucci, Nadia; Aroni, Kyriaki; Bacci, Mauro; Marcelli, Antonio; Rossi, Riccardo

2016-10-01

Sweat testing, an alternative matrix for establishing drug abuse, offers additional benefits to the more common biological samples. The authors developed a procedure using gas chromatography-mass spectrometry to test for Δ9-tetrahydrocannabinol, 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid, cannabinol (CBN), and cannabidiol (CBD) in a sweat patch. The results were compared with urine and hair sample results. Urine, hair, and sweat samples were simultaneously collected from 12 patients who were involved, respectively, in forensic case and monitoring abuse. Selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), recovery, intraday and interday imprecision, and inaccuracy of the quantification procedure were validated. LODs in hair were 0.05 ng/mg for Δ9-tetrahydrocannabinol, CBN, and CBD, and 0.005 ng/mg for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid. The LOD for sweat was 0.30 ng/patch for all substances. The LOQ in hair was 0.1 ng/mg for Δ9-tetrahydrocannabinol, CBN, and CBD, and 0.01 ng/mg for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid. The LOQ was 0.4 ng/patch in sweat for each analyte. Cannabinoid in urine was determined by means of immunochemical screening (cutoff 11-nor-Δ-tetrahydrocannabinol-9-carboxylic acid 50 ng/mL). All subjects tested positive for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid and Δ9-tetrahydrocannabinol in urine and hair. In sweat samples, Δ9-tetrahydrocannabinol was found in all patches (0.4-2.0 ng/patch); 6 cases were positive for CBN (0.4-0.5 ng/patch) and 3 for CBD (0.4-0.6 ng/patch); 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid was never detected in patches. Present sweat analysis results integrated the information from hair and urine and showed that sweat analysis is a suitable, noninvasive method for monitoring compliance with rehabilitation therapy and for detecting recent cumulative use of cannabinoids.

Cementitious materials for thin patches : final report.

DOT National Transportation Integrated Search

2001-06-01

Ten cementitious patching materials, which were suitable for thin, vertical repairs according to the manufacturers, were evaluated. Compatibility with cathodic protection systems was a particular concern. The materials were tested for propensity to c...

[Patch testing: historical aspects].

PubMed

Lachapelle, J-M

2009-01-01

This article reviews the key points in the history of patch testing, which spans more than a century, starting with the first description of the method by J. Jadassohn in 1895. Special attention is paid to the contribution of French schools in this field, which led to the foundation of the Groupe d'études et de recherches en dermato-allergologie (GERDA).

PL-PatchSurfer: a novel molecular local surface-based method for exploring protein-ligand interactions.

PubMed

Hu, Bingjie; Zhu, Xiaolei; Monroe, Lyman; Bures, Mark G; Kihara, Daisuke

2014-08-27

Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given protein based on their structural complementarity. Compared to other protein and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Here we developed a novel method named PL-PatchSurfer (Protein-Ligand PatchSurfer). PL-PatchSurfer represents the protein binding pocket and the ligand molecular surface as a combination of segmented surface patches. Each patch is characterized by its geometrical shape and the electrostatic potential, which are represented using the 3D Zernike descriptor (3DZD). We first tested PL-PatchSurfer on binding ligand prediction and found it outperformed the pocket-similarity based ligand prediction program. We then optimized the search algorithm of PL-PatchSurfer using the PDBbind dataset. Finally, we explored the utility of applying PL-PatchSurfer to a larger and more diverse dataset and showed that PL-PatchSurfer was able to provide a high early enrichment for most of the targets. To the best of our knowledge, PL-PatchSurfer is the first surface patch-based method that treats ligand complementarity at protein binding sites. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets.

PL-PatchSurfer: A Novel Molecular Local Surface-Based Method for Exploring Protein-Ligand Interactions

PubMed Central

Hu, Bingjie; Zhu, Xiaolei; Monroe, Lyman; Bures, Mark G.; Kihara, Daisuke

2014-01-01

Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given protein based on their structural complementarity. Compared to other protein and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Here we developed a novel method named PL-PatchSurfer (Protein-Ligand PatchSurfer). PL-PatchSurfer represents the protein binding pocket and the ligand molecular surface as a combination of segmented surface patches. Each patch is characterized by its geometrical shape and the electrostatic potential, which are represented using the 3D Zernike descriptor (3DZD). We first tested PL-PatchSurfer on binding ligand prediction and found it outperformed the pocket-similarity based ligand prediction program. We then optimized the search algorithm of PL-PatchSurfer using the PDBbind dataset. Finally, we explored the utility of applying PL-PatchSurfer to a larger and more diverse dataset and showed that PL-PatchSurfer was able to provide a high early enrichment for most of the targets. To the best of our knowledge, PL-PatchSurfer is the first surface patch-based method that treats ligand complementarity at protein binding sites. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets. PMID:25167137

The effect of habitat patch size on small mammal populations

Treesearch

Mark D. Yates; Susan C. Loeb; David C. Guynn

1997-01-01

Habitat fragmentation is one of the greatest threats to the conservation of bio­diversity and has 3 components: habitat loss, patch isolation, and patch size. The authors tested the effects of forest-clearing size on small mammal populations in the Upper Coastal Plain of South Carolina. These clearings act as islands for many species of small mam­mals, particularly old...

Cross-reactions among parabens, para-phenylenediamine, and benzocaine: a retrospective analysis of patch testing.

PubMed

Turchin, Irina; Moreau, Linda; Warshaw, Erin; Sasseville, Denis

2006-12-01

Parabens are alkyl ester derivatives of para-hydroxybenzoic acid and are the most commonly used preservatives in the cosmetic industry. Cross-reactions with para-amino compounds, namely, benzocaine and para-phenylenediamine (PPD), have been reported but are thought to be extremely rare. To evaluate the rate of cross-reactivity between parabens, PPD, and benzocaine in a population of patients patch-tested in a hospital-based contact dermatitis clinic. A retrospective analysis of 4,368 patients consecutively patch-tested between July 1989 and June 2005. Our study demonstrated that the rate of cross-reactions to parabens in PPD- and benzocaine-positive patients combined is 2%. This cross-reaction rate is significant in the tested population but still falls within the previously reported rates of sensitivity to parabens in the general population (0 to 3.5%).

Generic patches containing fentanyl: In vitro equivalence and abuse deterrent evaluation according to EMA and FDA guidelines.

PubMed

Padula, Cristina; Pescina, Silvia; Nicoli, Sara; Santi, Patrizia

2018-02-15

The aim of this work was to characterize in vitro and ex vivo the performances of Durogesic and of two bioequivalent generic products, by evaluating: (a) fentanyl release; (b) fentanyl permeation across porcine skin and (c) fentanyl ease of extraction. Additional characteristics studied are the effect of temperature and skin integrity, applied individually or combined, to check a possible synergism. The two generic patches resulted equivalent to the originator according to the new Guideline. Nevertheless, the same data reported in a different way, i.e. considering the total amount of drug permeated from the whole patch over the application time, highlight differences among the patches. The additional tests performed showed that skin integrity does not represent a barrier for fentanyl permeation across the skin, regardless of the type and complexity of the patch. The effect of temperature resulted critical for two out of three patches, probably due to the different composition and to the different structure. The combination of skin damage and elevated temperature did not produce a synergistic effect. Fentanyl extraction was different for the different products and variable according to the conditions used. The results reported in the present work underline the influence of patch composition and complexity on fentanyl extraction, release and skin permeation, in particular in conditions that can be critical, such as elevated temperature. In particular, the effect of critical variables, such as skin integrity and temperature, should be addressed to in the development of a new or new generic patch and new discriminant tests should be developed. Copyright © 2017 Elsevier B.V. All rights reserved.

Inferring local competition intensity from patch size distributions: a test using biological soil crusts

USGS Publications Warehouse

Bowker, Matthew A.; Maestre, Fernando T.

2012-01-01

Dryland vegetation is inherently patchy. This patchiness goes on to impact ecology, hydrology, and biogeochemistry. Recently, researchers have proposed that dryland vegetation patch sizes follow a power law which is due to local plant facilitation. It is unknown what patch size distribution prevails when competition predominates over facilitation, or if such a pattern could be used to detect competition. We investigated this question in an alternative vegetation type, mosses and lichens of biological soil crusts, which exhibit a smaller scale patch-interpatch configuration. This micro-vegetation is characterized by competition for space. We proposed that multiplicative effects of genetics, environment and competition should result in a log-normal patch size distribution. When testing the prevalence of log-normal versus power law patch size distributions, we found that the log-normal was the better distribution in 53% of cases and a reasonable fit in 83%. In contrast, the power law was better in 39% of cases, and in 8% of instances both distributions fit equally well. We further hypothesized that the log-normal distribution parameters would be predictably influenced by competition strength. There was qualitative agreement between one of the distribution's parameters (μ) and a novel intransitive (lacking a 'best' competitor) competition index, suggesting that as intransitivity increases, patch sizes decrease. The correlation of μ with other competition indicators based on spatial segregation of species (the C-score) depended on aridity. In less arid sites, μ was negatively correlated with the C-score (suggesting smaller patches under stronger competition), while positive correlations (suggesting larger patches under stronger competition) were observed at more arid sites. We propose that this is due to an increasing prevalence of competition transitivity as aridity increases. These findings broaden the emerging theory surrounding dryland patch size distributions and, with refinement, may help us infer cryptic ecological processes from easily observed spatial patterns in the field.

Sex differences in giraffe foraging behavior at two spatial scales.

PubMed

Ginnett, T F; Demment, Montague W

1997-04-01

We test predictions about differences in the foraging behaviors of male and female giraffes (Giraffa camelopardalis tippelskirchi Matchie) that derive from a hypothesis linking sexual size dimorphism to foraging behavior. This body-size hypothesis predicts that males will exhibit specific behaviors that increase their dry-matter intake rate relative to females. Foraging behavior was examined at two hierarchical levels corresponding to two spatial and temporal scales, within patches and within habitats. Patches are defined as individual trees or shrubs and habitats are defined as collections of patches within plant communities. Males were predicted to increase dry-matter intake rate within patches by taking larger bites, cropping bites more quickly, chewing less, and chewing faster. Within habitats, males were expected to increase intake rate by increasing the proportion of foraging time devoted to food ingestion as opposed to inter-patch travel time and vigilance. The predictions were tested in a free-ranging population of giraffes in Mikumi National Park, Tanzania. Males spent less total time foraging than females but allocated a greater proportion of their foraging time to forage ingestion as opposed to travel between patches. There was no sex difference in rumination time but males spent more time in activities other than foraging and rumination, such as walking. Within patches, males took larger bites than females, but females cropped bites more quickly and chewed faster. Males had longer per-bite handling times than females but had shorter handling times per gram of intake. Within habitats, males had longer average patch residence times but there was no significant sex difference in inter-patch travel times. There was no overall difference between sexes in vigilance while foraging, although there were significant sex by habitat and sex by season interactions. Although not all the predictions were confirmed, overall the results agree qualitatively with the body-size hypothesis. Sex-related differences in foraging behavior led to greater estimated intake rates for males at the within-patch and within-habitat scales.

Effects of Spatial Patch Arrangement and Scale of Covarying Resources on Growth and Intraspecific Competition of a Clonal Plant

PubMed Central

Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai

2016-01-01

Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale. PMID:27375630

Effects of Spatial Patch Arrangement and Scale of Covarying Resources on Growth and Intraspecific Competition of a Clonal Plant.

PubMed

Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai

2016-01-01

Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale.

Stability of fragrance patch test preparations applied in test chambers.

PubMed

Mowitz, M; Zimerson, E; Svedman, C; Bruze, M

2012-10-01

Petrolatum patch test preparations are for practical reasons often applied in test chambers in advance, several hours or even days before the patient is tested. As many fragrance compounds are volatile it may be suspected that petrolatum preparations applied in test chambers are not stable over time. To investigate the stability of petrolatum preparations of the seven chemically defined components in the fragrance mix (FM I) when stored in test chambers. Samples of petrolatum preparations applied in test chambers stored at room temperature and in a refrigerator for between 4 and 144 h were analysed using liquid chromatographic methods. The concentration decreased by ≥ 20% within 8 h in four of seven preparations stored in Finn chambers at room temperature. When stored in a refrigerator only the preparation of cinnamal had decreased by ≥ 20% within 24 h. The stability of preparations of cinnamal stored in IQ chambers with a plastic cover was slightly better, but like the preparations applied in Finn chambers, the concentration decreased by ≥ 20% within 4 h at room temperature and within 24 h in a refrigerator. Cinnamal and cinnamyl alcohol were found to be more stable when analysed as ingredients in FM I compared with when analysed in individual preparations. Within a couple of hours several fragrance allergens evaporate from test chambers to an extent that may affect the outcome of the patch test. Application to the test chambers should be performed as close to the patch test occasion as possible and storage in a refrigerator is recommended. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

Safety Evaluation of Silk Protein Film (A Novel Wound Healing Agent) in Terms of Acute Dermal Toxicity, Acute Dermal Irritation and Skin Sensitization

PubMed Central

Padol, Amol R.; Jayakumar, K.; Shridhar, N. B.; Narayana Swamy, H. D.; Narayana Swamy, M.; Mohan, K.

2011-01-01

Acute dermal toxicity study was conducted in rats. The parameters studied were body weight, serum biochemistry and gross pathology. The animals were also observed for clinical signs and mortality after the application of test film. The dermal irritation potential of silk protein film was examined using Draize test. In the initial test, three test patches were applied sequentially for 3 min, 1 and 4 hours, respectively, and skin reaction was graded. The irritant or negative response was confirmed using two additional animals, each with one patch, for an exposure period of 4 hours. The responses were scored at 1, 24, 48 and 72 hours after the patch removal. Skin sensitization study was conducted according to Buehler test in guinea pigs, in which on day 0, 7 and 14, the animals were exposed to test material for 6 hours (Induction phase) and on day 28, the animals were exposed for a period of 24 hours (Challenge phase). The skin was observed and recorded at 24 and 48 hours after the patch removal. In acute dermal toxicity study, the rats dermally treated with silk film did not show any abnormal clinical signs and the body weight, biochemical parameters and gross pathological observations were not significantly different from the control group. In acute dermal irritation study, the treated rabbits showed no signs of erythema, edema and eschar, and the scoring was given as “0” for all time points of observations according to Draize scoring system. In skin sensitization study, there were no skin reactions 24 and 48 hours after the removal of challenge patch, which was scored “0” based on Magnusson/Kligman grading scale. PMID:21430915

Diagnostic patch testing following tuberculosis-associated cutaneous adverse drug reactions induces systemic reactions in HIV-infected persons.

PubMed

Lehloenya, R J; Todd, G; Wallace, J; Ngwanya, M R; Muloiwa, R; Dheda, K

2016-07-01

The incidence of cutaneous adverse drug reactions (CADRs) to first-line antituberculosis drugs (FLTDs) is higher in HIV-tuberculosis coinfection. However, the utility of patch testing to identify the offending drug in this patient subgroup has been poorly studied. To identify drugs causing adverse drug reactions in patients with HIV-tuberculosis coinfection. Fourteen consecutive patients underwent diagnostic work-up (patch testing followed by a skin prick test and an oral rechallenge) to pinpoint the offending drug after developing FLTD-associated CADR, which included drug rash with eosinophilia and systemic symptoms (n = 12), Stevens-Johnson syndrome (SJS, n = 1) and toxic epidermal necrolysis/SJS overlap (n = 1). A positive reaction to any of the three diagnostic modalities eliminated that drug from the regimen. Once patients were clinically stable postreaction, sequential and additive rechallenge with FLTDs was initiated. Eleven of the 14 participants with FLTD-associated CADR were HIV infected (median CD4 count 149 cells mm(-3) ). In this subgroup, patch testing resulted in generalized systemic reactions in 10 of 11 patients (91%). These included rash in 10 of 13 reactions (77%), eosinophilia in eight (62%), transaminitis in seven (54%) and fever in five (38%). Isoniazid caused six of 13 (46%) generalized systemic reactions, rifampicin four (31%), ethambutol two (15%) and pyrazinamide one reaction. Using the Common Terminology Criteria for Adverse Events, five of 13 reactions were mild, six were moderate and two were severe. There were no life-threatening or fatal reactions. In HIV-infected persons with tuberculosis-associated CADR, although patch-testing reactions to FLTD are common and tend to be associated with systemic features, they are not life threatening or fatal. These data inform clinical practice in HIV-endemic settings. © 2016 British Association of Dermatologists.

Fabrication and Optimization of Stable, Optically Transparent, and Reusable pH-Responsive Silk Membranes

PubMed Central

Toytziaridis, Andreas; Dicko, Cedric

2016-01-01

The fabrication of silk-based membranes that are stable, optically transparent and reusable is yet to be achieved. To address this bottleneck we have developed a method to produce transparent chromogenic silk patches that are optically responsive to pH. The patches were produced by blending regenerated silk fibroin (RSF), Laponite RD (nano clay) and the organic dyes neutral red and Thionine acetate. The Laponite RD played a central role in the patch mechanical integrity and prevention of dye leaching. The process was optimized using a factorial design to maximize the patch response to pH by UV absorbance and fluorescence emission. New patches of the optimized protocol, made from solutions containing 125 μM neutral red or 250 μM of Thionine and 15 mg/mL silk, were further tested for operational stability over several cycles of pH altering. Stability, performance, and reusability were achieved over the tested cycles. The approach could be extended to other reporting molecules or enzymes able to bind to Laponite. PMID:27854303

Microstrip patch antenna for simultaneous strain and temperature sensing

NASA Astrophysics Data System (ADS)

Mbanya Tchafa, F.; Huang, H.

2018-06-01

A patch antenna, consisting of a radiation patch, a dielectric substrate, and a ground plane, resonates at distinct fundamental frequencies that depend on the substrate dielectric constant and the dimensions of the radiation patch. Since these parameters change with the applied strain and temperature, this study investigates simultaneous strain and temperature sensing using a single antenna that has two fundamental resonant frequencies. The theoretical relationship between the antenna resonant frequency shifts, the temperature, and the applied strain was first established to guide the selection of the dielectric substrate, based on which an antenna sensor with a rectangular radiation patch was designed and fabricated. A tensile test specimen instrumented with the antenna sensor was subjected to thermo-mechanical tests. Experiment results validated the theoretical predictions that the normalized antenna resonant frequency shifts are linearly proportional to the applied strain and temperature changes. An inverse method was developed to determine the strain and temperature changes from the normalized antenna resonant frequency shifts, yielding measurement uncertainty of 0.4 °C and 17.22 μ \\varepsilon for temperature and strain measurement, respectively.

Does Drug Testing Deter Drug Court Participants from Using Drugs or Alcohol?

ERIC Educational Resources Information Center

Kleinpeter, Christine B.; Brocato, Jo; Koob, Jeffrey J.

2010-01-01

This study evaluates 3 drug-testing strategies implemented in 5 different jurisdictions with drug courts in Orange County, California. The purpose of the study was to determine whether the sweat patch acts as a deterrent and under what conditions it can be used to improve outcomes. Results indicated that although the use of the sweat patch did not…

Occupational Contact Dermatitis in Mechanics and Repairers Referred for Patch Testing: Retrospective Analysis From the North American Contact Dermatitis Group 1998-2014.

PubMed

Warshaw, Erin M; Hagen, Solveig L; Sasseville, Denis; Maibach, Howard I; DeKoven, Joel G; Belsito, Donald V; Fowler, Joseph F; Zug, Kathryn A; Taylor, James S; Mathias, C G Toby; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Zirwas, Matthew J; Storrs, Frances J

Contact dermatoses are common in mechanic and repair occupations. This study aimed to (1) estimate the prevalence of occupationally related contact dermatitis among mechanics/repairers patch tested from 1998 to 2014 by the North American Contact Dermatitis Group, (2) characterize responsible allergens and irritants, and their sources, and (3) compare results among 3 occupational subgroups (mechanics, electrical/electronic, and other). A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 1998 and 2014. Of 38,784 patients patch tested, 691 (1.8%) were mechanics/repairers. Male sex (93.5%) and hand involvement (59.5%) were common overall. Occupationally related skin disease was more prevalent among vehicle and mobile equipment mechanics/repairers (52.7%) and other mechanics/repairers (41.4%) than electrical/electronic equipment mechanics/repairers (21.3%). Overall, carba mix, thiuram mix, and methylchloroisothiazolone/methylisothiazolone were the most common occupation-related clinically relevant allergens. Gloves, automotive vehicles, solvents, oils, lubricants, and fuels were the most common sources of responsible allergens. Common occupationally related allergens included rubber accelerators and the preservative methylchloroisothiazolone/methylisothiazolone.

Preparation of mucoadhesive oral patches containing tetracycline hydrochloride and carvacrol for treatment of local mouth bacterial infections and candidiasis.

PubMed

Obaidat, Rana M; Bader, Ammar; Al-Rajab, Wafa; Abu Sheikha, Ghassan; Obaidat, Aiman A

2011-01-01

The specific aim of this work was to prepare mucoadhesive patches containing tetracycline hydrochloride and carvacrol in an attempt to develop a novel oral drug delivery system for the treatment of mouth infections. The bilayered patches were prepared using ethyl cellulose as a backing layer and carbopol 934 as a matrix mucoadhesive layer. Patches were prepared with different loading amounts of tetracycline hydrochloride and carvacrol. The antimicrobial activity was assessed for the prepared patches using the disc-diffusion method against the yeast Candida albicans and five bacterial strains, including Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Bacillus bronchispti. In this work, we highlighted the possibility of occurrence of a synergistic action between carvacrol and tetracycline. The best formulation was selected based on microbiological tests, drug release, ex-vivo mucoadhesive performance, and swelling index. Physical characteristics of the selected formulations were determined. These included pH, patch thickness, weight uniformity, content uniformity, folding endurance, and patch stability.

Hydrologic connection between ponds positively affects macrophyte alpha and gamma diversity but negatively affects beta diversity.

PubMed

Akasaka, Munemitsu; Takamura, Noriko

2012-05-01

Connections between habitat patches can positively influence the number of species in respective patches, providing a basis for preferentially conserving interconnected patches. However, from a regional perspective, it is not known whether conserving multiple sets of interconnected habitat patches would include more species (i.e., show higher gamma diversity) than conserving multiple, unconnected, solitary patches. We studied aquatic macrophytes in 15 sets of unidirectionally interconnected ponds and 19 unconnected ponds and also tested whether alpha and beta diversity, expressed as the number of species and dissimilarity in species composition, respectively, differed between connected and unconnected ponds. We found that gamma diversity was higher in connected ponds than in unconnected ponds, even after controlling for surface area. This resulted from a higher alpha diversity in connected ponds, despite lower beta diversity. These results suggest that connections between habitat patches positively influence diversity at both local and regional scales. When the total surface area available for conservation is limited, interconnected habitat patches should be preferentially conserved.

Slowly inactivating component of Na+ current in peri-somatic region of hippocampal CA1 pyramidal neurons

PubMed Central

Park, Yul Young; Johnston, Daniel

2013-01-01

The properties of voltage-gated ion channels on the neuronal membrane shape electrical activity such as generation and backpropagation of action potentials, initiation of dendritic spikes, and integration of synaptic inputs. Subthreshold currents mediated by sodium channels are of interest because of their activation near rest, slow inactivation kinetics, and consequent effects on excitability. Modulation of these currents can also perturb physiological responses of a neuron that might underlie pathological states such as epilepsy. Using nucleated patches from the peri-somatic region of hippocampal CA1 neurons, we recorded a slowly inactivating component of the macroscopic Na+ current (which we have called INaS) that shared many biophysical properties with the persistent Na+ current, INaP, but showed distinctively faster inactivating kinetics. Ramp voltage commands with a velocity of 400 mV/s were found to elicit this component of Na+ current reliably. INaS also showed a more hyperpolarized I-V relationship and slower inactivation than those of the fast transient Na+ current (INaT) recorded in the same patches. The peak amplitude of INaS was proportional to the peak amplitude of INaT but was much smaller in amplitude. Hexanol, riluzole, and ranolazine, known Na+ channel blockers, were tested to compare their effects on both INaS and INaT. The peak conductance of INaS was preferentially blocked by hexanol and riluzole, but the shift of half-inactivation voltage (V1/2) was only observed in the presence of riluzole. Current-clamp measurements with hexanol suggested that INaS was involved in generation of an action potential and in upregulation of neuronal excitability. PMID:23236005

Patching. Restitching business portfolios in dynamic markets.

PubMed

Eisenhardt, K M; Brown, S L

1999-01-01

In turbulent markets, businesses and opportunities are constantly falling out of alignment. New technologies and emerging markets create fresh opportunities. Converging markets produce more. And of course, some markets fade. In this landscape of continuous flux, it's more important to build corporate-level strategic processes that enable dynamic repositioning than it is to build any particular defensible position. That's why smart corporate strategists use patching, a process of mapping and remapping business units to create a shifting mix of highly focused, tightly aligned businesses that can respond to changing market opportunities. Patching is not just another name for reorganizing; patchers have a distinctive mindset. Traditional managers see structure as stable; patching managers believe structure is inherently temporary. Traditional managers set corporate strategy first, but patching managers keep the organization focused on the right set of business opportunities and let strategy emerge from individual businesses. Although the focus of patching is flexibility, the process itself follows a pattern. Patching changes are usually small in scale and made frequently. Patching should be done quickly; the emphasis is on getting the patch about right and fixing problems later. Patches should have a test drive before they're formalized but then be tightly scripted after they've been announced. And patching won't work without the right infrastructure: modular business units, fine-grained and complete unit-level metrics, and companywide compensation parity. The authors illustrate how patching works and point out some common stumbling blocks.

Experimental Fatigue Study of Composite Patch Repaired Steel Plates with Cracks

NASA Astrophysics Data System (ADS)

Karatzas, Vasileios A.; Kotsidis, Elias A.; Tsouvalis, Nicholas G.

2015-10-01

Cracks are among the most commonly encountered defects in metallic structures operating at sea. Composite patch repairing is a repair method which is gaining popularity as it counters most of the problems faced by conventional renewal repairs. Extensive studies can be found in the literature addressing the efficiency of this novel repair method using techniques which meet higher performance and monitoring standards than these commonly found in naval applications. In this work the efficiency of practices widely used in the ship repair industry for the implementation of composite patch repairing is addressed. To this end, steel plates repaired with composite patches were tested under fatigue loading. The composite patches consisted of carbon fibers in epoxy matrix and were directly laminated to the steel surface using the vacuum infusion method. Two different surface preparation methods, namely grit-blasting and mechanical treatment with the use of a needle gun were studied. In addition, in order to account for the harsh environmental conditions during the operating life of the structure and to study its effect on the repair, two different aging scenarios were considered. Non-destructive evaluation of the patches was performed so as to assess the quality of the repair, and the evolution of debonding during testing.

Foraging decisions, patch use, and seasonality in egrets (Aves: ciconiiformes)

USGS Publications Warehouse

Erwin, R.M.

1985-01-01

Feeding snowy (Egretta thula) and great (Casmerodius albus) egrets were observed during 2 breeding seasons in coastal New Jersey and 2 brief winter periods in northeast Florida (USA). A number of tests based on assumptions of foraging models, predictions from foraging theory, and earlier empirical tests concerning time allocation and movement in foraging patches was made. Few of the expectations based on foraging theory and/or assumptions were supported by the empirical evidence. Snowy egrets fed with greater intensity and efficiency during the breeding season (when young were being fed) than during winter. They also showed some tendency to leave patches when their capture rate declined, and they spent more time foraging in patches when other birds were present nearby. Great egrets showed few of these tendencies, although they did leave patches when their intercapture intervals increased. Satiation differences had some influence on feeding rates in snowy egrets, but only at the end of feeding bouts. Some individuals of both species revisited areas in patches that had recently been exploited, and success rates were usually higher after the 2nd visit. Apparently, for predators of active prey, short-term changes in resource availability ('resource depression') may be more important than resource depletion, a common assumption in most optimal foraging theory models.

Can the epoxides of cinnamyl alcohol and cinnamal show new cases of contact allergy?

PubMed

Hagvall, Lina; Niklasson, Ida B; Luthman, Kristina; Karlberg, Ann-Therese

2018-06-01

Cinnamyl alcohol is considered to be a prohapten and prehapten with cinnamal as the main metabolite. However, many individuals who are allergic to cinnamyl alcohol do not react to cinnamal. Sensitizing epoxides of cinnamyl alcohol and cinnamal have been identified as metabolites and autoxidation products of cinnamyl alcohol. To investigate the clinical relevance of contact allergy to epoxycinnamyl alcohol and epoxycinnamal. Irritative effects of the epoxides were investigated in 12 dermatitis patients. Epoxycinnamyl alcohol and epoxycinnamal were patch tested in 393 and 390 consecutive patients, respectively. In parallel, cinnamyl alcohol and cinnamal were patch tested in 607 and 616 patients, respectively. Both epoxides were irritants, but no more positive reactions were detected than when testing was performed with cinnamyl alcohol and cinnamal. Late allergic reactions to epoxycinnamyl alcohol were observed. In general, patients with late reactions showed doubtful or positive reactions to cinnamal and fragrance mix I at regular patch testing. The investigated epoxides are not important haptens in contact allergy to cinnamon fragrance. The high frequency of fragrance allergy among patients included in the irritancy study showed the difficulty of suspecting fragrance allergy on the basis of history; patch testing broadly with fragrance compounds is therefore important. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Quantitative patch and repeated open application testing in hydroxyisohexyl 3-cyclohexene carboxaldehyde sensitive-patients.

PubMed

Schnuch, Axel; Uter, Wolfgang; Dickel, Heinrich; Szliska, Christiane; Schliemann, Sibylle; Eben, Ricarda; Ruëff, Franziska; Gimenez-Arnau, Ana; Löffler, Harald; Aberer, Werner; Frambach, Yvonne; Worm, Margitta; Niebuhr, Margarete; Hillen, Uwe; Martin, Vera; Jappe, Uta; Frosch, Peter J; Mahler, Vera

2009-09-01

To identify the concentration of the fragrance compound hydroxyisohexyl 3-cyclohexene carboxaldehyde (INCI) (HICC) that is sufficiently low not to cause an allergic reaction in patients with proven sensitization. Repeated open application testing (ROAT) in 64 subjects with 2 preparations (perfume and cream) in different concentration (0.005-2.5%). Confirmatory patch testing with four preparations in two different concentrations (2.5% and 5%). The concentrations of HICC being tolerated by 90% of those sensitized to HICC are estimated as <88.2 ppm (cream) and <270 ppm (perfume) equivalent to 1.2 microg/cm(2) (perfume) and 4.9 microg/cm(2) (cream). Patch test preparations differed with regard to sensitivity (88.5-98.1%) and specificity (37.5-87.5%) against the ROAT result as external criterion. ROAT concentrations and the reaction strength in patch testing were inversely correlated (Kendall's tau-b: 0.69), both indicating the existence of different degrees of susceptibility. To protect 90% (50%) of people sensitized, the use concentration should be in the range of 0.009-0.027% (0.18-0.34%), depending on the product type. Taking into account these results, excessive concentrations should be avoided, as this would continue to sensitize people. Close monitoring is indispensable to prove the efficacy of any recommendations aiming to prevent induction.

Patch testing with fragrance mix II: results of the IVDK 2005-2008.

PubMed

Krautheim, Andrea; Uter, Wolfgang; Frosch, Peter; Schnuch, Axel; Geier, Johannes

2010-11-01

The fragrance mix (FM I), established in 1977, detects the majority, but not all cases of contact allergy to fragrances. Based on European research 2002/2003, fragrance mix II (FM II) was developed to supplement FM I. In 2005, the German Contact Dermatitis Research Group (DKG) added FM II to their baseline series. To evaluate reactions to FM II and its constituents in routine patch testing. Retrospective data analysis of the Information Network of Departments of Dermatology (IVDK), 2005-2008, of patch test results with FM II and its constituents. A total of 35 633 patients were patch tested with FM II as part of the DKG baseline series. Of these, 1742 (4.9%) reacted positively. Concomitant reactions to FM I were observed in 41.9% of the patients reacting to FM II. In 367 FM II-positive patients, a full breakdown test of the mix was performed. Of these, 47.7% reacted to hydroxyisohexyl 3-cyclohexene carboxaldehyde, 16.1% to citral, 11.4% to farnesol, 3.8% to hexyl cinnamal, 2.7% to coumarin, and 2.5% to citronellol. FM II is an important screening and diagnostic tool to detect fragrance allergy. Hydroxyisohexyl 3-cyclohexene carboxaldehyde is the most important fragrance allergen in FM II. © 2010 John Wiley & Sons A/S.

Effect of isopropyl myristate on the viscoelasticity and drug release of a drug-in-adhesive transdermal patch containing blonanserinEffect of isopropyl myristate on the viscoelasticity and drug release of a drug-in-adhesive transdermal patch containing blonanserinretain-->.

PubMed

Zhao, Chunyi; Quan, Peng; Liu, Chao; Li, Qiaoyun; Fang, Liang

2016-11-01

The purpose of this study was to investigate the effect of isopropyl myristate (IPM), a penetration enhancer, on the viscoelasticity and drug release of a drug-in-adhesive transdermal patch containing blonanserin. The patches were prepared with DURO-TAK ® 87-2287 as a pressure-sensitive adhesive (PSA) containing 5% ( w / w ) of blonanserin and different concentrations of IPM. An in vitro release experiment was performed and the adhesive performance of the drug-in-adhesive patches with different concentrations of IPM was evaluated by a rolling ball tack test and a shear-adhesion test. The glass transition temperature ( T g ) and rheological parameters of the drug-in-adhesive layers were determined to study the effect of IPM on the mechanical properties of the PSA. The results of the in vitro release experiment showed that the release rate of blonanserin increased with an increasing concentration of IPM. The rolling ball tack test and shear-adhesion test showed decreasing values with increasing IPM concentration. The results were interpreted on the basis of the IPM-induced plasticization of the PSA, as evidenced by a depression of the glass transition temperature and a decrease in the elastic modulus. In conclusion, IPM acted as a plasticizer on DURO-TAK ® 87-2287, and it increased the release of blonanserin and affected the adhesive properties of the PSA.

Localizing tuberculosis in chest radiographs with deep learning

NASA Astrophysics Data System (ADS)

Xue, Zhiyun; Jaeger, Stefan; Antani, Sameer; Long, L. Rodney; Karargyris, Alexandros; Siegelman, Jenifer; Folio, Les R.; Thoma, George R.

2018-03-01

Chest radiography (CXR) has been used as an effective tool for screening tuberculosis (TB). Because of the lack of radiological expertise in resource-constrained regions, automatic analysis of CXR is appealing as a "first reader". In addition to screening the CXR for disease, it is critical to highlight locations of the disease in abnormal CXRs. In this paper, we focus on the task of locating TB in CXRs which is more challenging due to the intrinsic difficulty of locating the abnormality. The method is based on applying a convolutional neural network (CNN) to classify the superpixels generated from the lung area. Specifically, it consists of four major components: lung ROI extraction, superpixel segmentation, multi-scale patch generation/labeling, and patch classification. The TB regions are located by identifying those superpixels whose corresponding patches are classified as abnormal by the CNN. The method is tested on a publicly available TB CXR dataset which contains 336 TB images showing various manifestations of TB. The TB regions in the images were marked by radiologists. To evaluate the method, the images are split into training, validation, and test sets with all the manifestations being represented in each set. The performance is evaluated at both the patch level and image level. The classification accuracy on the patch test set is 72.8% and the average Dice index for the test images is 0.67. The factors that may contribute to misclassification are discussed and directions for future work are addressed.

Testing the feasibility of eliciting preferences for health states from adolescents using direct methods.

PubMed

Crump, R Trafford; Lau, Ryan; Cox, Elizabeth; Currie, Gillian; Panepinto, Julie

2018-06-22

Measuring adolescents' preferences for health states can play an important role in evaluating the delivery of pediatric healthcare. However, formal evaluation of the common direct preference elicitation methods for health states has not been done with adolescents. Therefore, the purpose of this study is to test how these methods perform in terms of their feasibility, reliability, and validity for measuring health state preferences in adolescents. This study used a web-based survey of adolescents, 18 years of age or younger, living in the United States. The survey included four health states, each comprised of six attributes. Preferences for these health states were elicited using the visual analogue scale, time trade-off, and standard gamble. The feasibility, test-retest reliability, and construct validity of each of these preference elicitation methods were tested and compared. A total of 144 participants were included in this study. Using a web-based survey format to elicit preferences for health states from adolescents was feasible. A majority of participants completed all three elicitation methods, ranked those methods as being easy, with very few requiring assistance from someone else. However, all three elicitation methods demonstrated weak test-retest reliability, with Kendall's tau-a values ranging from 0.204 to 0.402. Similarly, all three methods demonstrated poor construct validity, with 9-50% of all rankings aligning with our expectations. There were no significant differences across age groups. Using a web-based survey format to elicit preferences for health states from adolescents is feasible. However, the reliability and construct validity of the methods used to elicit these preferences when using this survey format are poor. Further research into the effects of a web-based survey approach to eliciting preferences for health states from adolescents is needed before health services researchers or pediatric clinicians widely employ these methods.

[Diagnostic workup of fragrance allergy].

PubMed

Geier, J; Uter, W

2015-09-01

The diagnostic workup of contact allergy to fragrances must not be limited to patch testing with the two well-established fragrance mixes. False-positive reactions to these mixes occur in up to 50 % of the patch tested patients. For the diagnostic work-up of positive reactions, and in cases of suspected fragrance allergy, patch testing with the single mix components and additional fragrances is mandatory. Frequently sensitizing fragrance materials are the 14 components of the two fragrance mixes and tree moss (Evernia furfuracea), ylang ylang oil (I + II; Cananga odorata), lemongrass oil (Cymbopogon schoenanthus), sandalwood oil (Santalum album), jasmine absolute (Jasminum spp.), and, less frequently, clove oil (Eugenia caryophyllus), cedarwood oil (Cedrus atlantica/deodara, Juniperus virginiana), Neroli oil (Citrus aurantium amara flower oil), salicylaldehyde, narcissus absolute (Narcissus spp.), and patchouli oil (Pogostemon cablin).

A rivastigmine patch for the treatment of Alzheimer's disease and Parkinson's disease dementia.

PubMed

Cummings, Jeffrey; Winblad, Bengt

2007-11-01

Rivastigmine patch is the first transdermal treatment to be approved for Alzheimer's disease (AD) and Parkinson's disease dementia in the USA and for AD in Europe. It provides smooth, continuous drug delivery, and has the potential to maintain rivastigmine concentrations within an optimal therapeutic window while avoiding the peaks and troughs associated with oral drug delivery. The target dose, rivastigmine 9.5 mg/24 h patch (a 10 cm(2) patch), is given once daily and requires a simple one-step dose titration to the therapeutic dose. In a 24-week study in 1195 AD patients, the rivastigmine 9.5 mg/24 h patch provided similar efficacy to the highest dose range of capsules, with approximately three-times fewer reports of nausea and vomiting. Patients in the 9.5 mg/24 h patch and 12 mg/day capsule groups evidenced significant improvements versus placebo on both primary outcome measures: the Alzheimer's Disease Assessment Scale-Cognitive subscale; and Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change; in addition to the following secondary outcome measures: Alzheimer's Disease Cooperative Study-Activities of Daily Living scale; Mini-Mental State Examination; and Trail Making Test Part A for assessment of attention, visual tracking and motor processing speed. Treatment differences on the Neuropsychiatric Inventory and Ten Point Clock-drawing Test did not reach statistical significance in this study. The patch may be the optimal way to treat dementia patients with rivastigmine.

Contact allergy to common ingredients in hair dyes.

PubMed

Søsted, Heidi; Rustemeyer, Thomas; Gonçalo, Margarida; Bruze, Magnus; Goossens, An; Giménez-Arnau, Ana M; Le Coz, Christophe J; White, Ian R; Diepgen, Thomas L; Andersen, Klaus E; Agner, Tove; Maibach, Howard; Menné, Torkil; Johansen, Jeanne D

2013-07-01

p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed. To examine whether PPD is an optimal screening agent for diagnosing hair dye allergy or whether other clinically important sensitizers exist. Two thousand nine hundred and thirty-nine consecutive patients in 12 dermatology clinics were patch tested with five hair dyes available from patch test suppliers. Furthermore, 22 frequently used hair dye ingredients not available from patch test suppliers were tested in subgroups of ~500 patients each. A positive reaction to PPD was found in 4.5% of patients, and 2.8% reacted to toluene-2,5-diamine (PTD), 1.8% to p-aminophenol, 1% to m-aminophenol, and 0.1% to resorcinol; all together, 5.3% (n = 156). Dying hair was the most frequently reported cause of the allergy (55.4%); so-called 'temporary henna' tattoos were the cause in 8.5% of the cases. p-Methylaminophenol gave a reaction in 20 patients (2.2%), 3 of them with clinical relevance, and no co-reaction with the above five well-known hair dyes. Hair dyes are the prime cause of PPD allergy. PPD identifies the majority of positive reactions to PTD, p-aminophenol and m-aminophenol, but not all, which justifies additional testing with hair dye ingredients from the used product. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

North American Contact Dermatitis Group patch test results for 2007-2008.

PubMed

Fransway, Anthony F; Zug, Kathryn A; Belsito, Donald V; Deleo, Vincent A; Fowler, Joseph F; Maibach, Howard I; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Rietschel, Robert L; Sasseville, Denis; Storrs, Frances J; Taylor, James S; Warshaw, Erin M; Dekoven, Joel; Zirwas, Matthew

2013-01-01

The North American Contact Dermatitis Group (NACDG) tests patients with suspected allergic contact dermatitis to a broad series of screening allergens and publishes periodic reports. The aims of this study were to report the NACDG patch-testing results from January 1, 2007, to December 31, 2008, and to compare results to pooled test data from the previous 2 and 10 years to analyze trends in allergen sensitivity. Standardized patch testing with 65 allergens was used at 13 centers in North America. χ analysis was used for comparisons. A total of 5085 patients were tested; 11.8% (598) had an occupationally related skin condition, and 65.3% (3319) had at least 1 allergic patch test reaction, which is identical to the NACDG data from 2005 to 2006. The top 15 most frequently positive allergens were nickel sulfate (19.5%), Myroxylon pereirae (11.0%), neomycin (10.1%), fragrance mix I (9.4%), quaternium-15 (8.6%), cobalt chloride (8.4%), bacitracin (7.9%), formaldehyde (7.7%), methyldibromoglutaronitrile/phenoxyethanol (5.5%), p-phenylenediamine (5.3%), propolis (4.9%), carba mix (4.5%), potassium dichromate (4.1%), fragrance mix II (3.6%), and methylchloroisothiazolinone/methylisothiazolinone (3.6%). There were significant increases in positivity rates to nickel, methylchloroisothiazolinone/methylisothiazolinone, and benzophenone-3. During the same period of study, there were significant decreases in positivity rates to neomycin, fragrance mix I, formaldehyde, thiuram mix, cinnamic aldehyde, propylene glycol, epoxy resin, diazolidinyl urea, amidoamine, ethylenediamine, benzocaine, p-tert-butylphenol formaldehyde resin, dimethylol dimethyl hydantoin, cocamidopropyl betaine, glutaraldehyde, mercaptobenzothiazole, tosylamide formaldehyde resin, budesonide, disperse blue 106, mercapto mix, and chloroxylenol. Twenty-four percent (1221) had a relevant positive reaction to a non-NACDG supplementary allergen; and 180 of these reactions were occupationally relevant. Periodic analysis, surveillance, and publication of multicenter study data sets document trends in allergen reactivity incidence assessed in the patch test clinic setting and provide information on new allergens of relevance.

A study of human recognition rates for foveola-sized image patches selected from initial and final fixations on calibrated natural images

NASA Astrophysics Data System (ADS)

van der Linde, Ian; Rajashekar, Umesh; Cormack, Lawrence K.; Bovik, Alan C.

2005-03-01

Recent years have seen a resurgent interest in eye movements during natural scene viewing. Aspects of eye movements that are driven by low-level image properties are of particular interest due to their applicability to biologically motivated artificial vision and surveillance systems. In this paper, we report an experiment in which we recorded observers" eye movements while they viewed calibrated greyscale images of natural scenes. Immediately after viewing each image, observers were shown a test patch and asked to indicate if they thought it was part of the image they had just seen. The test patch was either randomly selected from a different image from the same database or, unbeknownst to the observer, selected from either the first or last location fixated on the image just viewed. We find that several low-level image properties differed significantly relative to the observers" ability to successfully designate each patch. We also find that the differences between patch statistics for first and last fixations are small compared to the differences between hit and miss responses. The goal of the paper was to, in a non-cognitive natural setting, measure the image properties that facilitate visual memory, additionally observing the role that temporal location (first or last fixation) of the test patch played. We propose that a memorability map of a complex natural scene may be constructed to represent the low-level memorability of local regions in a similar fashion to the familiar saliency map, which records bottom-up fixation attractors.

Pediatric Contact Dermatitis Registry Data on Contact Allergy in Children With Atopic Dermatitis.

PubMed

Jacob, Sharon E; McGowan, Maria; Silverberg, Nanette B; Pelletier, Janice L; Fonacier, Luz; Mousdicas, Nico; Powell, Doug; Scheman, Andrew; Goldenberg, Alina

2017-08-01

Atopic dermatitis (AD) and allergic contact dermatitis (ACD) have a dynamic relationship not yet fully understood. Investigation has been limited thus far by a paucity of data on the overlap of these disorders in pediatric patients. To use data from the Pediatric Contact Dermatitis Registry to elucidate the associations and sensitizations among patients with concomitant AD and ACD. This retrospective case review examined 1142 patch test cases of children younger than 18 years, who were registered between January 1, 2015, and December 31, 2015, by 84 health care providers (physicians, nurse practitioners, physician assistants) from across the United States. Data were gathered electronically from multidisciplinary providers within outpatient clinics throughout the United States on pediatric patients (ages 0-18 years). All participants were patch-tested to assess sensitizations to various allergens; history of AD was noted by the patch-testing providers. Primary outcomes were sensitization rates to various patch-tested allergens. A total of 1142 patients were evaluated: 189 boys (34.2%) and 363 girls (65.8%) in the AD group and 198 boys (36.1%) and 350 girls (63.9%) in the non-AD group (data on gender identification were missing for 17 patients). Compared with those without AD, patch-tested patients with AD were 1.3 years younger (10.5 vs 11.8 years; P < .001) and had longer history of dermatitis (3.5 vs 1.8 years; P < .001). Patch-tested patients designated as Asian or African American were more likely to have concurrent AD (odds ratio [OR], 1.92; 95% CI, 1.20-3.10; P = .008; and OR, 4.09; 95% CI, 2.70-6.20; P <.001, respectively). Patients with AD with generalized distribution were the most likely to be patch tested (OR, 4.68; 95% CI, 3.50-6.30; P < .001). Patients with AD had different reaction profiles than those without AD, with increased frequency of reactions to cocamidopropyl betaine, wool alcohol, lanolin, tixocortol pivalate, and parthenolide. Patients with AD were also noted to have lower frequency of reaction to methylisothiazolinone, cobalt, and potassium dichromate. Children with AD showed significant reaction patterns to allergens notable for their use in skin care preparations. This study adds to the current understanding of AD in ACD, and the continued need to investigate the interplay between these disease processes to optimize care for pediatric patients with these conditions.

Pediatric Contact Dermatitis Registry Data on Contact Allergy in Children With Atopic Dermatitis

PubMed Central

Jacob, Sharon E.; McGowan, Maria; Silverberg, Nanette B.; Pelletier, Janice L.; Fonacier, Luz; Mousdicas, Nico; Powell, Doug; Scheman, Andrew

2017-01-01

Importance Atopic dermatitis (AD) and allergic contact dermatitis (ACD) have a dynamic relationship not yet fully understood. Investigation has been limited thus far by a paucity of data on the overlap of these disorders in pediatric patients. Objective To use data from the Pediatric Contact Dermatitis Registry to elucidate the associations and sensitizations among patients with concomitant AD and ACD. Design, Setting, and Participants This retrospective case review examined 1142 patch test cases of children younger than 18 years, who were registered between January 1, 2015, and December 31, 2015, by 84 health care providers (physicians, nurse practitioners, physician assistants) from across the United States. Data were gathered electronically from multidisciplinary providers within outpatient clinics throughout the United States on pediatric patients (ages 0-18 years). Exposures All participants were patch-tested to assess sensitizations to various allergens; history of AD was noted by the patch-testing providers. Main Outcomes and Measures Primary outcomes were sensitization rates to various patch-tested allergens. Results A total of 1142 patients were evaluated: 189 boys (34.2%) and 363 girls (65.8%) in the AD group and 198 boys (36.1%) and 350 girls (63.9%) in the non-AD group (data on gender identification were missing for 17 patients). Compared with those without AD, patch-tested patients with AD were 1.3 years younger (10.5 vs 11.8 years; P < .001) and had longer history of dermatitis (3.5 vs 1.8 years; P < .001). Patch-tested patients designated as Asian or African American were more likely to have concurrent AD (odds ratio [OR], 1.92; 95% CI, 1.20-3.10; P = .008; and OR, 4.09; 95% CI, 2.70-6.20; P <.001, respectively). Patients with AD with generalized distribution were the most likely to be patch tested (OR, 4.68; 95% CI, 3.50-6.30; P < .001). Patients with AD had different reaction profiles than those without AD, with increased frequency of reactions to cocamidopropyl betaine, wool alcohol, lanolin, tixocortol pivalate, and parthenolide. Patients with AD were also noted to have lower frequency of reaction to methylisothiazolinone, cobalt, and potassium dichromate. Conclusions and Relevance Children with AD showed significant reaction patterns to allergens notable for their use in skin care preparations. This study adds to the current understanding of AD in ACD, and the continued need to investigate the interplay between these disease processes to optimize care for pediatric patients with these conditions. PMID:28241280

Metapopulation responses to patch connectivity and quality are masked by successional habitat dynamics.

PubMed

Hodgson, Jenny A; Moilanen, Atte; Thomas, Chris D

2009-06-01

Many species have to track changes in the spatial distribution of suitable habitat from generation to generation. Understanding the dynamics of such species will likely require spatially explicit models, and patch-based metapopulation models are potentially appropriate. However, relatively little attention has been paid to developing metapopulation models that include habitat dynamics, and very little to testing the predictions of these models. We tested three predictions from theory about the differences between dynamic habitat metapopulations and their static counterparts using long-term survey data from two metapopulations of the butterfly Plebejus argus. As predicted, we showed first that the metapopulation inhabiting dynamic habitat had a lower level of habitat occupancy, which could not be accounted for by other differences between the metapopulations. Secondly, we found that patch occupancy did not significantly increase with increasing patch connectivity in dynamic habitat, whereas there was a strong positive connectivity-occupancy relationship in static habitat. Thirdly, we found no significant relationship between patch occupancy and patch quality in dynamic habitat, whereas there was a strong, positive quality-occupancy relationship in static habitat. Modeling confirmed that the differences in mean patch occupancy and connectivity-occupancy slope could arise without changing the species' metapopulation parameters-importantly, without changing the dependence of colonization upon connectivity. We found that, for a range of landscape scenarios, successional simulations always produced a lower connectivity-occupancy slope than comparable simulations with static patches, whether compared like-for-like or controlling for mean occupancy. We conclude that landscape-scale studies may often underestimate the importance of connectivity for species occurrence and persistence because habitat turnover can obscure the connectivity-occupancy relationship in commonly available snapshot data.

Is a specific eyelid patch test series useful? Results of a French prospective study.

PubMed

Assier, Haudrey; Tetart, Florence; Avenel-Audran, Martine; Barbaud, Annick; Ferrier-le Bouëdec, Marie-Christine; Giordano-Labadie, Françoise; Milpied, Brigitte; Amsler, Emmanuelle; Collet, Evelyne; Girardin, Pascal; Soria, Angèle; Waton, Julie; Truchetet, François; Bourrain, Jean-Luc; Gener, Gwendeline; Bernier, Claire; Raison-Peyron, Nadia

2018-06-08

Eyelids are frequent sites of contact dermatitis. No prospective study focused on eyelid allergic contact dermatitis (EACD) has yet been published, and this topic has never been studied in French patients. To prospectively evaluate the usefulness of an eyelid series in French patients patch tested because of EACD, and to describe these patients. We prospectively analysed standardized data for all patients referred to our departments between September 2014 and August 2016 for patch testing for suspected EACD as the main reason. All patients were patch tested with an eyelid series, the European baseline series (EBS), the French additional series, and their personal products. Patch testing with additional series and repeated open application tests (ROATs) or open tests were performed if necessary. A standardized assessment of the relevance was used, and the analysis of the results was focused on patients having positive test results with a current certain relevance. Two-hundred and sixty-four patients (238 women and 26 men) were included. Three-hundred and twenty-two tests gave positive results in 167 patients, 84 of whom had currently relevant reactions: 56 had currently relevant positive test reactions to the EBS, 16 had currently relevant positive test reactions to their personal products, 8 had currently relevant positive test reactions to the French additional series, and 4 had currently relevant positive test reactions to the eyelid series. Sixty-seven per cent of all relevant cases were related to cosmetic products. The most frequent allergens with current relevance were methylisothiazolinone (10.2%), fragrance mix I (3%), nickel (2.7%), hydroxyperoxides of linalool (2.7%) and limonene (2.3%), and Myroxylon pereirae (2.3%). Current atopic dermatitis was found in 9.5% of patients. The duration of dermatitis was shorter (23.2 vs 34.2 months; P = .035) in patients with currently relevant test reactions. The percentage of currently relevant tests remained the same when atopic patients or dermatitis localized only on the eyelids were taken into account. In French patients, testing for EACD with the extended baseline series and personal products, also including ROATs and use tests, appears to be adequate, considering the currently relevant positive test reactions. The regular addition of an eyelid series does not seem to be necessary. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Chamber Tests with Human Subjects XX. Hypersensitivity to H as Demonstrated by Patch Tests Before and After Chamber Exposure to H Vapor

DTIC Science & Technology

1946-05-15

worn. In addition to erythema, edema and/or folliculitis were observed in only 2 of 230 men tested prior to exposure to H vapor. After exposure, 26% of...169 men manifested edema and/or folliculitis to patch tests. These men were arbitrarily considered "sensitized". This sensitized group also showed a...for edema or folliculitis , a value CONFIDENT-L.f, - 6 - C:7 Fx was calculated in which readings of 16 were assigned their erythema value of 8 and

Novel agonistic action of mustard oil on recombinant and endogenous porcine transient receptor potential V1 (pTRPV1) channels.

PubMed

Ohta, Toshio; Imagawa, Toshiaki; Ito, Shigeo

2007-05-15

Neurogenic components play a crucial role in inflammation and nociception. Mustard oil (MO) is a pungent plant extract from mustard seed, horseradish and wasabi, the main constituent of which is allylisothiocyanate. We have characterized the action of MO on transient receptor potential V1 (TRPV1), a key receptor of signal transduction pathways in the nociceptive system, using fura-2-based [Ca(2+)](i) imaging and the patch-clamp technique in a heterologous expression system and sensory neurons. In human embryonic kidney (HEK) 293 cells expressing porcine TRPV1 (pTRPV1), MO evoked increases of [Ca(2+)](i) in a concentration-dependent manner. A high concentration of MO elicited irreversible cell swelling. Capsazepine, ruthenium red and iodoresiniferatoxin dose-dependently suppressed the MO-induced [Ca(2+)](i) increase. MO elicited outward rectified currents in pTRPV1-expressing HEK 293 cells with a reversal potential similar to that of capsaicin. [Ca(2+)](i) responses to MO were completely abolished by the removal of external Ca(2+). MO simultaneously elicited an inward current and increase of [Ca(2+)](i) in the same cells, indicating that MO promoted Ca(2+) influx through TRPV1 channels. In cultured porcine dorsal root ganglion (DRG) neurons, MO elicited a [Ca(2+)](i) increase and inward current. Among DRG neurons responding to MO, 85% were also sensitive to capsaicin. The present data indicate that MO is a novel agonist of TRPV1 channels, and suggest that the action of MO in vivo may be partly mediated via TRPV1. These results provide an insight into the TRPV1-mediated effects of MO on inflammation and hyperalgesia.

A clinical study of transdermal contraceptive patch in Thai adolescence women.

PubMed

Piyasirisilp, Rachatapon; Taneepanichskul, Surasak

2008-02-01

To study cycle control, compliance and safety of a transdermal contraceptive patch in adolescent Thai women. Fifty-eight healthy women were assigned to receive 3 cycles of contraceptive patch (ethinyl estradiol 20 microg and norelgestromin 150 microg/day). All participants aged 16-20 years were invited to participate from the family planning clinic at King Chulalongkorn Memorial Hospital. Data were collected on adverse effects, perceived advantages and disadvantages, body weight, blood pressure, patch detachments and compliance. Data were analyzed using mean, percentage and student's t-test. The participants' average age was 19.4 years, height 158.8 cm, weight 51.8 kg, BMI 20.8 Kg/m2. The most location of patch application was the abdomen and the most adverse event was breast tenderness (31.0%) followed by application site reaction, nausea vomiting and headache respectively. The breast symptom was mild in severity. The participants reported decrease in dysmenorrhea and shorter duration of bleeding. There were no significant changes in body weight and blood pressure. The improvement of their facial acne was reported. There were no pregnancies during use and the adhesion of the contraceptive patch is excellent. Partial patch detachment was reported in only 6.9%. No completed patch detachment was found. The present study found an overall positive impression of a new transdermal contraceptive patch. The good compliance and few side effects were demonstrated. The adhesive patch contraceptive was excellent.

Eosinophilic airway disease in a patient with a negative skin prick test, but a positive patch test with platinum salts--implications for medical surveillance.

PubMed

Merget, Rolf; Fartasch, Manigé; Sander, Ingrid; Van Kampen, Vera; Raulf, Monika; Brüning, Thomas

2015-09-01

We present the case of a 52-year-old woman with a topic dermatitis since adolescence who developed work-related hand eczema, cough and runny nose 12 years after she had started working as a laboratory technician at a precious metals refinery. While skin prick test with sodium hexachloroplatinate (SPTPt ) was negative, patch testing with ammonium tetrachloroplatinate was positive after 24, 48, 72, and 96 hr. Inhalation challenge with sodium hexachloroplatinate yielded cough, mild shortness of breath, and a maximal decrease of FEV1 of 8% from baseline 24 hr after the challenge. Significant increases of bronchial hyperresponsiveness, exhaled nitric monoxide and sputum eosinophils were documented after the challenge. We conclude that eosinophilic airway disease due to platinum salts may occur in SPTPt negative subjects. Both, patch testing and inhalation challenge with platinum salts should be considered in SPT negative subjects with occupational exposure to precious metal salts and work-related allergic symptoms. © 2015 Wiley Periodicals, Inc.

Patch Testing for Evaluation of Hypersensitivity to Implanted Metal Devices: A Perspective From the American Contact Dermatitis Society.

PubMed

Schalock, Peter C; Crawford, Glen; Nedorost, Susan; Scheinman, Pamela L; Atwater, Amber Reck; Mowad, Christen; Brod, Bruce; Ehrlich, Alison; Watsky, Kalman L; Sasseville, Denis; Silvestri, Dianne; Worobec, Sophie M; Elliott, John F; Honari, Golara; Powell, Douglas L; Taylor, James; DeKoven, Joel

2016-01-01

The American Contact Dermatitis Society recognizes the interest in the evaluation and management of metal hypersensitivity reactions. Given the paucity of robust evidence with which to guide our practices, we provide reasonable evidence and expert opinion-based guidelines for clinicians with regard to metal hypersensitivity reaction testing and patient management. Routine preoperative evaluation in individuals with no history of adverse cutaneous reactions to metals or history of previous implant-related adverse events is not necessary. Patients with a clear self-reported history of metal reactions should be evaluated by patch testing before device implant. Patch testing is only 1 element in the assessment of causation in those with postimplantation morbidity. Metal exposure from the implanted device can cause sensitization, but a positive metal test does not prove symptom causality. The decision to replace an implanted device must include an assessment of all clinical factors and a thorough risk-benefit analysis by the treating physician(s) and patient.

Allergic contact dermatitis from a natural deodorant: a report of 4 cases associated with lichen acid mix allergy.

PubMed

Sheu, Mary; Simpson, Eric L; Law, Sandra V; Storrs, Frances J

2006-08-01

Botanical ingredients used in personal care products are a significant and underreported cause of allergic contact dermatitis. To evaluate allergic contact dermatitis from a widely-used botanical deodorant. We conducted patch testing in four patients who were using the botanical deodorant and were referred to the contact dermatitis clinic; three patients had axillary dermatitis and one had dermatitis of the external ear. All four patients had positive patch test reactions to lichen acid mix and D-usnic acid. Of the three patients who were patch tested to the botanical deodorant, all had positive reactions. We did not test to the specific lichen used in the natural deodorant but rather used our own lichen acid mix and d-usnic acid in addition to testing to the actual product. One of the patients declined to be tested with the natural deodorant, but did test positive to the lichen acid mix and d-usnic acid. Personal care products such as deodorants may represent a new route of exposure to lichen extract, a known allergen.

Relative abundance of mesopredators and size of oak patches in the cross-timbers ecoregion

USGS Publications Warehouse

Disney, M.R.; Hellgren, E.C.; Davis, C.A.; Leslie, David M.; Engle, David M.

2008-01-01

Mesopredators (e.g., raccoon Procyon lotor, Virginia opossum Didelphis virginiana, striped skunk Mephitis mephitis) have received considerable attention because of links to population declines in birds via increased nest predation, especially in landscapes fragmented by anthropogenic forces. Relationships of abundance of mesopredators to size of habitat patches have received less attention than relationships to other metrics of fragmentation, particularly edge characteristics. We tested the hypothesis that relative abundance of mesopredators (e.g., raccoons and Virginia opossums) was related negatively to size of forest patch. We delineated 15 patches of oak (Quercus) forest ranging from 0.2 to 55.3 ha within a grassland-woodland mosaic in the cross-timbers ecoregion of Oklahoma. Scent stations and live traps within these patches were used to index relative abundance of mesopredators in summers 2003 and 2004. Both indices of relative abundance were related weakly and negatively to area of forest patch. However, rate of capture and visitation to scent station were not correlated consistently throughout the study. Our results suggested that the two methods to index abundance provided separate information on functional and numerical responses to size of patch. Our evidence that mesopredators within the cross timbers were more likely to be in smaller patches of oak forest may have implications to success of avian nesting in these patches.

Utilization of MatPIV program to different geotechnical models

NASA Astrophysics Data System (ADS)

Aklik, P.; Idinger, G.

2009-04-01

The Particle Imaging Velocimetry (PIV) technique is being used to measure soil displacements. PIV has been used for many years in fluid mechanics; but for physical modeling in geotechnical engineering, this technique is still relatively new. PIV is a worldwide growth in soil mechanics over the last decade owing to the developments in digital cameras and laser technologies. The use of PIV is feasible provided the surface contains sufficient texture. A Cambridge group has shown that natural sand contains enough texture for applying PIV. In a texture-based approach, the only requirement is for any patch, big or small to be sufficiently unique so that statistical tracking of this patch is possible. In this paper, some of the soil mechanic's models were investigated such as retaining walls, slope failures, and foundations. The photographs were taken with the help of the high resolution digital camera, the displacements of soils were evaluated with free software named as MatPIV and the displacement graphics between the two images were obtained. Nikon D60 digital camera is 10.2 MB and it has special properties which makes it possible to use in PIV applications. These special properties are Airflow Control System and Image Sensor cleaning for protection against dust, Active D-Lighting for highlighted or shadowy areas while shooting, advanced three-point AF system for fast, efficient and precise autofocus. Its fast and continuous shooting mode enables up to 100 JPEG images at three frames per second. Norm Sand (DIN 1164) was used for all the models in a glass rectangular box. For every experiment, MatPIV was used to calculate the velocities from the two images. MatPIV program was used in two ways such as easy way and difficult way: In the easy way, the two images with 64*64 pixels with 50% or 75% overlap of the interrogation windows were taken into consideration and the calculation was performed with a single iteration through the images and the result consisted of four matrices measured in pixels and pixels/second. At the end of the iteration, the results were visualized. In the application of difficult way of MatPIV, a grid of points into the research model was inserted and the first image was taken with the Nikon D60 digital camera. Afterwards, how large a pixel in the image and the orientation of the coordinate system were calculated. If there are no particles to perform PIV calculations in the investigated region, the best way is to mask out this empty region. The crucial step in PIV is the particle image analysis, which is to determine the displacements between two successive images. The first image was divided into a grid of test patches. Each test patch consisted of a sample of the image matrix of size L * L pixels. To find the displacement of the test patch between images 1 and 2, a search patch was extracted from the second image. The cross-correlation of test patch and search patch was evaluated. The resulting normalized correlation plane indicated the "degree of match" between the test and search patch. The highest peak in the normalized correlation plane indicated the displacement vector of the test patch. The procedure described above for evaluation a single displacement vector was repeated for the entire grid of test patches, producing the displacement field between the image pair. After having performed the calculations, there were so many wild vectors due to low image quality in some parts of the images to be removed with the help of the different filters. There are four different filters in MatPIV, these are: signal-to-noise ratio filter, peak height filter, global filter, and local filter. The filters were used step by step to decide which filter could give the best result for the related images. As a last step, both of the ways were compared in each geotechnical model.

Evaluation of materials proposed for use in space flight

NASA Technical Reports Server (NTRS)

Duncan, W. C.

1981-01-01

The cutaneous primary irritancy and allergenicity potential of cotton shirts/fabrics treated with flame retardants were evaluated in order to establish their suitability for spacecraft crew use. Twenty-five volunteer human subjects were patch tested on the back utilizing standard methodology, with both treated and untreated cotton fabric. The fabric was treated with tetrakis (hydroxymethyl) phosphonium hydroxide and subsequently cured with gaseous ammonia. The final treatment comprised adding on dicyandiamine phosphoric acid. None of the individuals experienced primary irritant or allergic reactions attributable to the fabric during induction or challenge patch testing. Likewise, there were no reactions to treated or untreated fabric patches placed on ten subjects of the usage panel at the conclusion of the study.

Role of Bacterial Communities in the Natural Suppression of Rhizoctonia solani Bare Patch Disease of Wheat (Triticum aestivum L.)

PubMed Central

Yin, Chuntao; Hulbert, Scot H.; Schroeder, Kurtis L.; Mavrodi, Olga; Mavrodi, Dmitri; Dhingra, Amit; Schillinger, William F.

2013-01-01

Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga, Pedobacter, Oxalobacteriaceae (Duganella and Massilia), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia-inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease. PMID:24056471

Development of a self-stressing NiTiNb shape memory alloy (SMA)/fiber reinforced polymer (FRP) patch

NASA Astrophysics Data System (ADS)

El-Tahan, M.; Dawood, M.; Song, G.

2015-06-01

The objective of this research is to develop a self-stressing patch using a combination of shape memory alloys (SMAs) and fiber reinforced polymer (FRP) composites. Prestressed carbon FRP patches are emerging as a promising alternative to traditional methods to repair cracked steel structures and civil infrastructure. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This paper presents a new approach in which the prestressing force is applied by restraining the shape memory effect of NiTiNb SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing. This paper presents the conceptual development of the self-stressing patch with the support of experimental observations. The bond between the SMA wires and the FRP is evaluated using pull-out tests. The paper concludes with an experimental study that evaluates the patch response during activation subsequent monotonic tensile loading. The results demonstrate that the self-stressing patch with NiTiNb SMA is capable of generating a significant prestressing force with minimal tool and labor requirements.

Pattern does not equal process: what does patch occupancy really tell us about metapopulation dynamics?

PubMed

Clinchy, Michael; Haydon, Daniel T; Smith, Andrew T

2002-04-01

Patch occupancy surveys are commonly used to parameterize metapopulation models. If isolation predicts patch occupancy, this is generally attributed to a balance between distance-dependent recolonization and spatially independent extinctions. We investigated whether similar patterns could also be generated by a process of spatially correlated extinctions following a unique colonization event (analogous to nonequilibrium processes in island biogeography). We simulated effects of spatially correlated extinctions on patterns of patch occupancy among pikas (Ochotona princeps) at Bodie, California, using randomly located extinction disks to represent the likely effects of predation. Our simulations produced similar patterns to those cited as evidence of balanced metapopulation dynamics. Simulations using a variety of disk sizes and patch configurations confirmed that our results are potentially applicable to a broad range of species and sites. Analyses of the observed patterns of patch occupancy at Bodie revealed little evidence of rescue effects and strong evidence that most recolonizations are ephemeral in nature. Persistence will be overestimated if static or declining patterns of patch occupancy are mistakenly attributed to dynamically stable metapopulation processes. Consequently, simple patch occupancy surveys should not be considered as substitutes for detailed experimental tests of hypothesized population processes, particularly when conservation concerns are involved.

Toothpaste allergy as a cause of cheilitis in Israeli patients.

PubMed

Lavy, Yaron; Slodownik, Dan; Trattner, Akiva; Ingber, Arieh

2009-01-01

Allergic contact cheilitis may appear after exposure to different substances, including dental materials, toothpastes, cosmetics, foods and medications. To compare the rate of toothpaste allergy between patients with and without cheilitis and to examine the yield of our proposed toothpaste patch test kit for use in patients with cheilitis. A patch test kit containing 11 substances used in toothpastes was formed. The study sample consisted of 44 patients, 24 with cheilitis (study group) and 20 with contact dermatitis but without cheilitis (control group). Eleven patients in the study group (45%) were found to be allergic to toothpaste, compared to only one patient (5%) in the control group (p < .05). The rate of toothpaste allergy among patients with cheilitis might be higher than previously reported. Patch-testing with our toothpaste series is recommended in the evaluation of cheilitis.

A Measure of Proficiency or Short-Term Memory? Validation of an Elicited Imitation Test for SLA Research

ERIC Educational Resources Information Center

Kim, Youjin; Tracy-Ventura, Nicole; Jung, Yeonjoo

2016-01-01

Elicited imitation requires listeners to listen and repeat sentences as accurately as possible. In second language acquisition (SLA) research it has been used for a variety of purposes. Recently, versions of the same elicited imitation test (EIT) have been created in 6 languages with the purpose of measuring second language proficiency (Ortega…

Anomaly detection for medical images based on a one-class classification

NASA Astrophysics Data System (ADS)

Wei, Qi; Ren, Yinhao; Hou, Rui; Shi, Bibo; Lo, Joseph Y.; Carin, Lawrence

2018-02-01

Detecting an anomaly such as a malignant tumor or a nodule from medical images including mammogram, CT or PET images is still an ongoing research problem drawing a lot of attention with applications in medical diagnosis. A conventional way to address this is to learn a discriminative model using training datasets of negative and positive samples. The learned model can be used to classify a testing sample into a positive or negative class. However, in medical applications, the high unbalance between negative and positive samples poses a difficulty for learning algorithms, as they will be biased towards the majority group, i.e., the negative one. To address this imbalanced data issue as well as leverage the huge amount of negative samples, i.e., normal medical images, we propose to learn an unsupervised model to characterize the negative class. To make the learned model more flexible and extendable for medical images of different scales, we have designed an autoencoder based on a deep neural network to characterize the negative patches decomposed from large medical images. A testing image is decomposed into patches and then fed into the learned autoencoder to reconstruct these patches themselves. The reconstruction error of one patch is used to classify this patch into a binary class, i.e., a positive or a negative one, leading to a one-class classifier. The positive patches highlight the suspicious areas containing anomalies in a large medical image. The proposed method has been tested on InBreast dataset and achieves an AUC of 0.84. The main contribution of our work can be summarized as follows. 1) The proposed one-class learning requires only data from one class, i.e., the negative data; 2) The patch-based learning makes the proposed method scalable to images of different sizes and helps avoid the large scale problem for medical images; 3) The training of the proposed deep convolutional neural network (DCNN) based auto-encoder is fast and stable.

Generative adversarial networks for brain lesion detection

NASA Astrophysics Data System (ADS)

Alex, Varghese; Safwan, K. P. Mohammed; Chennamsetty, Sai Saketh; Krishnamurthi, Ganapathy

2017-02-01

Manual segmentation of brain lesions from Magnetic Resonance Images (MRI) is cumbersome and introduces errors due to inter-rater variability. This paper introduces a semi-supervised technique for detection of brain lesion from MRI using Generative Adversarial Networks (GANs). GANs comprises of a Generator network and a Discriminator network which are trained simultaneously with the objective of one bettering the other. The networks were trained using non lesion patches (n=13,000) from 4 different MR sequences. The network was trained on BraTS dataset and patches were extracted from regions excluding tumor region. The Generator network generates data by modeling the underlying probability distribution of the training data, (PData). The Discriminator learns the posterior probability P (Label Data) by classifying training data and generated data as "Real" or "Fake" respectively. The Generator upon learning the joint distribution, produces images/patches such that the performance of the Discriminator on them are random, i.e. P (Label Data = GeneratedData) = 0.5. During testing, the Discriminator assigns posterior probability values close to 0.5 for patches from non lesion regions, while patches centered on lesion arise from a different distribution (PLesion) and hence are assigned lower posterior probability value by the Discriminator. On the test set (n=14), the proposed technique achieves whole tumor dice score of 0.69, sensitivity of 91% and specificity of 59%. Additionally the generator network was capable of generating non lesion patches from various MR sequences.

Manufacturing and testing of active composite panels with embedded piezoelectric sensors and actuators: wires out by molded-in holes

NASA Astrophysics Data System (ADS)

Ghasemi-Nejhad, Mehrdad N.; Pourjalali, Saeid

2003-08-01

This work presents manufacturing and testing of active composite panels (ACPs) with embedded piezoelectric sensors and actuators. The composite material employed here is a plain weave carbon epoxy prepreg fabric with about 0.33 mm ply thickness. The piezoelectric patches employed here are Continuum Control Corporation, CCC, (recently Continuum Photonics, Inc) active fiber composite patches with 0.33 mm thickness, i.e. close to the composite ply thickness. Composite cut-out layers are used to fill the space around the embedded piezoelectric patches to minimize the problems associated with ply drops in composites. The piezoelectric patches were embedded inside the composite laminate. High-temperature wires were soldered to the piezoelectric leads, insulated from the carbon substructure by high-temperature materials, and were taken out of the composite laminates employing a molded-in hole technique that reduces the stress concentration as opposed to a drilled hole, and thereby enhancing the performance of the composite structure. The laminated ACP"s were co-cured inside an autoclave employing the cure cycle recommended by the composite material supplier. The curie temperature of the embedded piezoelectric patches should be well above the curing temperature of the composite materials as was the case here. The manufactured ACP beams and plates were trimmed and then tested for their functionality. Vibration suppression as well as simultaneous vibration suppression and precision positioning tests, using PID control as well as Hybrid Adaptive Control techniques were successfully conducted on the manufactured ACP beams and their functionality were demonstrated. Recommendations on the use of this embedding technique for ACPs are provided.

Parallel traveling-wave MRI: a feasibility study.

PubMed

Pang, Yong; Vigneron, Daniel B; Zhang, Xiaoliang

2012-04-01

Traveling-wave magnetic resonance imaging utilizes far fields of a single-piece patch antenna in the magnet bore to generate radio frequency fields for imaging large-size samples, such as the human body. In this work, the feasibility of applying the "traveling-wave" technique to parallel imaging is studied using microstrip patch antenna arrays with both the numerical analysis and experimental tests. A specific patch array model is built and each array element is a microstrip patch antenna. Bench tests show that decoupling between two adjacent elements is better than -26-dB while matching of each element reaches -36-dB, demonstrating excellent isolation performance and impedance match capability. The sensitivity patterns are simulated and g-factors are calculated for both unloaded and loaded cases. The results on B 1- sensitivity patterns and g-factors demonstrate the feasibility of the traveling-wave parallel imaging. Simulations also suggest that different array configuration such as patch shape, position and orientation leads to different sensitivity patterns and g-factor maps, which provides a way to manipulate B(1) fields and improve the parallel imaging performance. The proposed method is also validated by using 7T MR imaging experiments. Copyright © 2011 Wiley-Liss, Inc.

Designing and testing a wearable, wireless fNIRS patch.

PubMed

Abtahi, Mohammadreza; Cay, Gozde; Saikia, Manob Jyoti; Mankodiya, Kunal

2016-08-01

Optical brain monitoring using near infrared (NIR) light has got a lot of attention in order to study the complexity of the brain due to several advantages as oppose to other methods such as EEG, fMRI and PET. There are a few commercially available functional NIR spectroscopy (fNIRS) brain monitoring systems, but they are still non-wearable and pose difficulties in scanning the brain while the participants are in motion. In this work, we present our endeavors to design and test a low-cost, wireless fNIRS patch using NIR light sources at wavelengths of 770 and 830nm, photodetectors and a microcontroller to trigger the light sources, read photodetector's output and transfer data wirelessly (via Bluetooth) to a smart-phone. The patch is essentially a 3-D printed wearable system, recording and displaying the brain hemodynamic responses on smartphone, also eliminates the need for complicated wiring of the electrodes. We have performed rigorous lab experiments on the presented system for its functionality. In a proof of concept experiment, the patch detected the NIR absorption on the arm. Another experiment revealed that the patch's battery could last up to several hours with continuous fNIRS recording with and without wireless data transfer.

Patch testing in Israeli children with suspected allergic contact dermatitis: A retrospective study and literature review.

PubMed

Zafrir, Yaron; Trattner, Akiva; Hodak, Emmillia; Eldar, Oren; Lapidoth, Moshe; Ben Amitai, Dan

2018-01-01

Childhood allergic contact dermatitis is recognized as a significant clinical problem. The objective was to evaluate the rate of positive patch tests in Israeli children with clinically suspected allergic contact dermatitis, identify possible sex and age differences, compare results with those in Israeli adults, and review pediatric studies in the literature. The study sample included 343 children and adolescents (197 female, 146 male; 1-18 years of age, mean age 11.8 years) with clinically suspected allergic contact dermatitis who underwent patch testing with a standard pediatric series of 23 allergens at a tertiary medical center from 1999 to 2012. Data on clinical characteristics and test results were collected retrospectively from the medical files. Ninety-eight subjects (28.6%) (75 girls [38.1%], 23 boys [15.8%]) had at least one positive reaction. The most frequent reactions were to nickel sulfate, followed by potassium dichromate and cobalt chloride. Nickel sulfate sensitivity was more common in girls, especially those younger than 3 years and older than 12 years. The prevalence of contact sensitization was similar in subjects with and without atopic dermatitis (50% and 51%, respectively). Nickel is the most common allergen in Israeli children, especially girls. Patch testing should be performed in children with clinically suspected allergic contact dermatitis regardless of atopic background. © 2017 Wiley Periodicals, Inc.

A review of 241 subjects who were patch tested twice: could fragrance mix I cause active sensitization?

PubMed

White, J M L; McFadden, J P; White, I R

2008-03-01

Active patch test sensitization is an uncommon phenomenon which may have undesirable consequences for those undergoing this gold-standard investigation for contact allergy. To perform a retrospective analysis of the results of 241 subjects who were patch tested twice in a monocentre evaluating approximately 1500 subjects per year. Positivity to 11 common allergens in the recommended Baseline Series of contact allergens (European) was analysed: nickel sulphate; Myroxylon pereirae; fragrance mix I; para-phenylenediamine; colophonium; epoxy resin; neomycin; quaternium-15; thiuram mix; sesquiterpene lactone mix; and para-tert-butylphenol resin. Only fragrance mix I gave a statistically significant, increased rate of positivity on the second reading compared with the first (P=0.011). This trend was maintained when separately analysing a subgroup of 42 subjects who had been repeat patch tested within 1 year; this analysis was done to minimize the potential confounding factor of increased usage of fragrances with a wide interval between both tests. To reduce the confounding effect of age on our data, we calculated expected frequencies of positivity to fragrance mix I based on previously published data from our centre. This showed a marked excess of observed cases over predicted ones, particularly in women in the age range 40-60 years. We suspect that active sensitization to fragrance mix I may occur. Similar published analysis from another large group using standard methodology supports our data.

North American Contact Dermatitis Group patch test results: 2009 to 2010.

PubMed

Warshaw, Erin M; Belsito, Donald V; Taylor, James S; Sasseville, Denis; DeKoven, Joel G; Zirwas, Matthew J; Fransway, Anthony F; Mathias, C G Toby; Zug, Kathryn A; DeLeo, Vincent A; Fowler, Joseph F; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Maibach, Howard I

2013-01-01

Patch testing is an important diagnostic tool for determination of substances responsible for allergic contact dermatitis. This study reports the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2009, to December 31, 2010. At 12 centers in North America, patients were tested in a standardized manner with a screening series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends were analyzed using χ2 statistics. A total of 4308 patients were tested. Of these, 2614 (60.7%) had at least 1 positive reaction, and 2284 (46.3%) were ultimately determined to have a primary diagnosis of allergic contact dermatitis. Four hundred twenty-seven (9.9%) patients had occupationally related skin disease. There were 6855 positive allergic reactions. As compared with the previous reporting period (2007-2008), the positive reaction rates statistically decreased for 20 allergens (nickel, neomycin, Myroxylon pereirae, cobalt, formaldehyde, quaternium 15, methydibromoglutaronitrile/phenoxyethanol, methylchlorisothiazolinone/methylisothiazolinone, potassium dichromate, diazolidinyl urea, propolis, dimethylol dimethylhydantoin, 2-bromo-2-nitro-1,3-propanediol, methyl methacrylate, ethyl acrylate, glyceryl thioglycolate, dibucaine, amidoamine, clobetasol, and dimethyloldihydroxyethyleneurea; P < 0.05) and statistically increased for 4 allergens (fragrance mix II, iodopropynyl butylcarbamate, propylene glycol, and benzocaine; P < 0.05). Approximately one quarter of tested patients had at least 1 relevant allergic reaction to a non-NACDG allergen. Hypothetically, approximately one quarter of reactions detected by NACDG allergens would have been missed by TRUE TEST (SmartPractice Denmark, Hillerød, Denmark). These results affirm the value of patch testing with many allergens.

A rare allergy to a polyether dental impression material.

PubMed

Mittermüller, Pauline; Szeimies, Rolf-Markus; Landthaler, Michael; Schmalz, Gottfried

2012-08-01

Polyether impression materials have been used in dentistry for more than 40 years. Allergic reactions to these materials such as reported in the 1970s ceased after replacement of a catalyst. Very recently, however, patients have started to report symptoms that suggest a new allergic reaction from polyether impression materials. Here, we report on the results of allergy testing with polyether impression materials as well as with its components. Eight patients with clinical symptoms of a contact allergy (swelling, redness or blisters) after exposure to a polyether impression material were subjected to patch tests, two of them additionally to a prick test. A further patient with atypical symptoms of an allergy (nausea and vomiting after contact with a polyether impression material in the oral cavity) but with a history of other allergic reaction was also patch tested. The prick tests showed no immediate reactions in the two patients tested. In the patch tests, all eight patients with typical clinical symptoms showed positive reactions to the mixed polyether impression materials, to the base paste or to a base paste component. The patient with the atypical clinical symptoms did not show any positive patch test reactions. Polyether impression materials may evoke type IV allergic reactions. The causative agent was a component of the base paste. In consideration of the widespread use of this impression material (millions of applications per year) and in comparison to the number of adverse reactions from other dental materials, the number of such allergic reactions is very low. In very scarce cases, positive allergic reactions to polyether impression materials are possible.

Patch testing with uranyl acetate in veterans exposed to depleted uranium during the 1991 Gulf war and the Iraqi conflict.

PubMed

Shvartsbeyn, Marianna; Tuchinda, Papapit; Gaitens, Joanna; Squibb, Katherine S; McDiarmid, Melissa A; Gaspari, Anthony A

2011-01-01

The Depleted Uranium Follow-Up Program is a clinical surveillance program run by the Baltimore Veterans Affairs Medical Center since 1993 for veterans of the Gulf and Iraqi wars who were exposed to depleted uranium (DU) as a result of "friendly-fire" incidents. In 2009, 40 veterans from this cohort were screened for skin reactivity to metals by patch-testing with extended metal series and uranyl acetate (0.25%, 2.5%, and 25%). A control arm comprised 46 patients without any known occupational exposures to DU who were seen at the University of Maryland Dermatology Clinic for evaluation of allergic contact dermatitis. Excluding irritant reactions, no patch-test reactions to uranyl acetate were observed in the participants. Irritant reactions to DU were more common in the clinic cohort, likely reflective of the demographic differences between the two arms of the study. Biologic monitoring of urine uranium concentrations in the DU program participants with 24-hour urine samples showed evidence of percutaneous uranium absorption from the skin patches. We conclude that dermatitis observed in a subset of the veterans was unrelated to their military DU exposure. Our data suggest that future studies of skin testing with uranyl acetate should utilize 0.25%, the least irritating concentration.

Patch test results of the dental personnel with contact dermatitis.

PubMed

Kocak, Oguzhan; Gul, Ulker

2014-12-01

Dental personnel have high risk of occupational contact dermatitis. The aim of this study is to detect the materials which cause contact sensitization and the frequency of contact dermatitis by using patch tests with European standard series and dental screening series in dental personnel. Between August 2008 and July 2009, 461 dental personnel working in Ankara (Turkey) were examined and age, gender, previous history of dermatitis, area of the skin affected and clinical diagnosis were noted. About 198 (43%) of the dental personnel were diagnosed contact dermatitis. Sixty-five of the dental personnel accepted to be patch tested. Dental technicians, dentists and dental nurses constitute 69.2%, 24.6% and 6.2% of patch tested 65 patients, respectively. Positive reactions to at least one allergen were detected with European standard series at 20% and with dental series at 10.8% among the dental personnel. The most common allergens were nickel sulfate (12.3%), acrylates (6.1%) and para-tertiary-butylphenol-formaldehyde resin (4.6%). The most common acrylate was ethyleneglycol dimethacrylate (3.1%). We believe our study will be helpful to dermatologists about frequency of contact dermatitis among dental personnel and allergens that cause contact sensitivity for developing new methods to protect the personnel in dentistry against sensitization.

Contact allergy in cheilitis.

PubMed

O'Gorman, Susan M; Torgerson, Rochelle R

2016-07-01

Recalcitrant non-actinic cheilitis may indicate contact allergy. This study aimed to determine the prevalence of allergic contact cheilitis (ACC) in patients with non-actinic cheilitis and to identify the most relevant allergens. We used an institutional database to identify patients with non-actinic cheilitis who underwent patch testing between January 1, 2001, and August 31, 2011, and conducted a retrospective review of patch test results in these patients. Additional data were obtained from institutional electronic medical records. Ninety-one patients (70 [77%] female; mean age: 51 years) were included in the study. Almost half (41 [45%]) had a final diagnosis of ACC. Patch testing was performed in line with universally accepted methods, with application on day 1, allergen removal and an initial reading on day 3, and the final reading on day 5. The allergens of most significance were fragrance mix, Myroxylon pereirae resin, dodecyl gallate, octyl gallate, and benzoic acid. Nickel was the most relevant metal allergen. Contact allergy is an important consideration in recalcitrant cheilitis. Fragrances, antioxidants, and preservatives dominated the list of relevant allergens in our patients. Nickel and gold were among the top 10 allergens. Almost half (45%) of these patients had a final diagnosis of ACC. Patch testing beyond the oral complete series should be undertaken in any investigation of non-actinic cheilitis. © 2015 The International Society of Dermatology.

Airborne occupational allergic contact dermatitis from triglycidyl-p-aminophenol and tetraglycidyl-4,4'-methylene dianiline in preimpregnated epoxy products in the aircraft industry.

PubMed

Kanerva, L; Jolanki, R; Estlander, T; Henriks-Eckerman, M; Tuomi, M; Tarvainen, K

2000-01-01

Very little is known about allergic contact dermatitis (ACD) from preimpregnated epoxy products (prepregs). To describe a patient with occupational ACD from prepregs, and report new quantitative data on the content of prepregs. A laminator developed work-related vesicular hand dermatitis. He worked in an aircraft plant assembling aircraft parts, being exposed to preimpregnated carbon fiber and fiberglass sheets (prepregs), and epoxy adhesive tapes and foams. Triglycidyl-p-aminophenol (TGPAP; 1-0.25%, 2+; 0.05%, 1+) and tetraglycidyl-4,4'-methylene dianiline (TGMDA; 1%, 3+; 0.5-0.05%, 2+) provoked allergic patch test reactions, whereas o-diglycidyl phthalate was negative (1-0.05% pet) and standard epoxy provoked a weak (?+) reaction. Six prepreg products provoking allergic patch test reactions were analyzed for their TGPAP, TGMDA and diglycidyl ether of bisphenol A (DGEBA) content using gas and liquid chromatographic methods, showing up to 10% of TGPAP, 19% of TGMDA and 5% of DGEBA in the prepregs. An epoxy primer contained 61% of TGPAP. TGPAP and TGMDA caused occupational ACD. These chemicals need to be used when patch testing patients are exposed to prepregs, because patch testing with DGEBA may be negative. Copyright 2000 S. Karger AG, Basel.

Shoe contact dermatitis from dimethyl fumarate: clinical manifestations, patch test results, chemical analysis, and source of exposure.

PubMed

Giménez-Arnau, Ana; Silvestre, Juan Francisco; Mercader, Pedro; De la Cuadra, Jesus; Ballester, Isabel; Gallardo, Fernando; Pujol, Ramón M; Zimerson, Erik; Bruze, Magnus

2009-11-01

The methyl ester form of fumaric acid named dimethyl fumarate (DMF) is an effective mould-growth inhibitor. Its irritating and sensitizing properties were demonstrated in animal models. Recently, DMF has been identified as responsible for furniture contact dermatitis in Europe. To describe the clinical manifestations, patch test results, shoe chemical analysis, and source of exposure to DMF-induced shoe contact dermatitis. Patients with suspected shoe contact dermatitis were studied in compliance with the Declaration of Helsinki. Patch test results obtained with their own shoe and the European baseline series, acrylates and fumaric acid esters (FAE), were recorded according to international guidelines. The content of DMF in shoes was analysed with gas chromatography and mass spectrometry. Acute, immediate irritant contact dermatitis and non-immunological contact urticaria were observed in eight adults and two children, respectively. All the adult patients studied developed a delayed sensitization demonstrated by a positive patch testing to DMF < or = 0.1% in pet. Cross-reactivity with other FAEs and acrylates was observed. At least 12 different shoe brands were investigated. The chemical analysis from the available shoes showed the presence of DMF. DMF in shoes was responsible for severe contact dermatitis. Global preventive measures for avoiding contact with DMF are necessary.

The contraceptive vaginal ring, NuvaRing(®), a decade after its introduction.

PubMed

Roumen, Frans J M E; Mishell, Daniel R

2012-12-01

To review the clinical experience with the contraceptive vaginal ring (CVR, NuvaRing(®)) since its introduction over ten years ago. The literature was searched on efficacy, cycle control, safety, user preference and satisfaction of the CVR in comparison with combined oral contraceptives (COCs) and the patch, with special attention to recent developments. The ring has the same working mechanism and contraindications as COCs. Serum levels of steroids are steadier, whereas oestrogenic exposure is lower. Contraceptive efficacy is similar, as are metabolic changes. Cycle control is better, and compliance and continuation rates are equal or higher. Oestrogen-related adverse symptoms appear to be fewer, but reports on the incidence of venous thrombosis are conflicting. Expulsion of the ring is reported by 4% to 20% of women. Local adverse events are the main reason for discontinuation. Acceptability is as high as with COCs and, after structured counselling, the ring is preferred by many women to the pill or the patch. Efficacy of the CVR, and the metabolic changes and adverse events it elicits, are generally comparable to those of COCs, yet oestrogenic exposure is lower and cycle control superior. After counselling, the ring is preferred to the pill by many women.

Temporal Statistics of Natural Image Sequences Generated by Movements with Insect Flight Characteristics

PubMed Central

Schwegmann, Alexander; Lindemann, Jens Peter; Egelhaaf, Martin

2014-01-01

Many flying insects, such as flies, wasps and bees, pursue a saccadic flight and gaze strategy. This behavioral strategy is thought to separate the translational and rotational components of self-motion and, thereby, to reduce the computational efforts to extract information about the environment from the retinal image flow. Because of the distinguishing dynamic features of this active flight and gaze strategy of insects, the present study analyzes systematically the spatiotemporal statistics of image sequences generated during saccades and intersaccadic intervals in cluttered natural environments. We show that, in general, rotational movements with saccade-like dynamics elicit fluctuations and overall changes in brightness, contrast and spatial frequency of up to two orders of magnitude larger than translational movements at velocities that are characteristic of insects. Distinct changes in image parameters during translations are only caused by nearby objects. Image analysis based on larger patches in the visual field reveals smaller fluctuations in brightness and spatial frequency composition compared to small patches. The temporal structure and extent of these changes in image parameters define the temporal constraints imposed on signal processing performed by the insect visual system under behavioral conditions in natural environments. PMID:25340761

Surgery for left ventricular aneurysm: early and late survival after simple linear repair and endoventricular patch plasty.

PubMed

Lundblad, Runar; Abdelnoor, Michel; Svennevig, Jan Ludvig

2004-09-01

Simple linear resection and endoventricular patch plasty are alternative techniques to repair postinfarction left ventricular aneurysm. The aim of the study was to compare these 2 methods with regard to early mortality and long-term survival. We retrospectively reviewed 159 patients undergoing operations between 1989 and 2003. The epidemiologic design was of an exposed (simple linear repair, n = 74) versus nonexposed (endoventricular patch plasty, n = 85) cohort with 2 endpoints: early mortality and long-term survival. The crude effect of aneurysm repair technique versus endpoint was estimated by odds ratio, rate ratio, or relative risk and their 95% confidence intervals. Stratification analysis by using the Mantel-Haenszel method was done to quantify confounders and pinpoint effect modifiers. Adjustment for multiconfounders was performed by using logistic regression and Cox regression analysis. Survival curves were analyzed with the Breslow test and the log-rank test. Early mortality was 8.2% for all patients, 13.5% after linear repair and 3.5% after endoventricular patch plasty. When adjusted for multiconfounders, the risk of early mortality was significantly higher after simple linear repair than after endoventricular patch plasty (odds ratio, 4.4; 95% confidence interval, 1.1-17.8). Mean follow-up was 5.8 +/- 3.8 years (range, 0-14.0 years). Overall 5-year cumulative survival was 78%, 70.1% after linear repair and 91.4% after endoventricular patch plasty. The risk of total mortality was significantly higher after linear repair than after endoventricular patch plasty when controlled for multiconfounders (relative risk, 4.5; 95% confidence interval, 2.0-9.7). Linear repair dominated early in the series and patch plasty dominated later, giving a possible learning-curve bias in favor of patch plasty that could not be adjusted for in the regression analysis. Postinfarction left ventricular aneurysm can be repaired with satisfactory early and late results. Surgical risk was lower and long-term survival was higher after endoventricular patch plasty than simple linear repair. Differences in outcome should be interpreted with care because of the retrospective study design and the chronology of the 2 repair methods.

Robust Observation Detection for Single Object Tracking: Deterministic and Probabilistic Patch-Based Approaches

PubMed Central

Zulkifley, Mohd Asyraf; Rawlinson, David; Moran, Bill

2012-01-01

In video analytics, robust observation detection is very important as the content of the videos varies a lot, especially for tracking implementation. Contrary to the image processing field, the problems of blurring, moderate deformation, low illumination surroundings, illumination change and homogenous texture are normally encountered in video analytics. Patch-Based Observation Detection (PBOD) is developed to improve detection robustness to complex scenes by fusing both feature- and template-based recognition methods. While we believe that feature-based detectors are more distinctive, however, for finding the matching between the frames are best achieved by a collection of points as in template-based detectors. Two methods of PBOD—the deterministic and probabilistic approaches—have been tested to find the best mode of detection. Both algorithms start by building comparison vectors at each detected points of interest. The vectors are matched to build candidate patches based on their respective coordination. For the deterministic method, patch matching is done in 2-level test where threshold-based position and size smoothing are applied to the patch with the highest correlation value. For the second approach, patch matching is done probabilistically by modelling the histograms of the patches by Poisson distributions for both RGB and HSV colour models. Then, maximum likelihood is applied for position smoothing while a Bayesian approach is applied for size smoothing. The result showed that probabilistic PBOD outperforms the deterministic approach with average distance error of 10.03% compared with 21.03%. This algorithm is best implemented as a complement to other simpler detection methods due to heavy processing requirement. PMID:23202226

Development of a Remote External Repair Tool for Damaged or Defective Polyethylene Pipe

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

Kenneth H. Green; Willie E. Rochefort; Nick Wannenmacher

2006-06-30

Current procedures for repairing polyethylene (PE) gas pipe require excavation, isolation, and removal of the damaged section of pipe followed by fusing a new section of pipe into place. These techniques are costly and very disruptive. An alternative repair method was developed at Timberline Tool with support from Oregon State University (OSU) and funding by the U. S. Department of Energy National Energy Technology Laboratory (DOE/NETL). This project was undertaken to design, develop and test a tool and method for repairing damaged PE pipe remotely and externally in situ without squeezing off the flow of gas, eliminating the need formore » large-scale excavations. Through an iterative design and development approach, a final engineered prototype was developed that utilizes a unique thermo-chemical and mechanical process to apply a permanent external patch to repair small nicks, gouges and punctures under line pressure. The project identified several technical challenges during the design and development process. The repair tool must be capable of being installed under live conditions and operate in an 18-inch keyhole. This would eliminate the need for extensive excavations thus reducing the cost of the repair. Initially, the tool must be able to control the leak by encapsulating the pipe and apply slight pressure at the site of damage. Finally, the repair method must be permanent at typical operating pressures. The overall results of the project have established a permanent external repair method for use on damaged PE gas pipe in a safe and cost-effective manner. The engineered prototype was subjected to comprehensive testing and evaluation to validate the performance. Using the new repair tool, samples of 4-inch PE pipe with simulated damage were successfully repaired under line pressure to the satisfaction of DOE/NETL and the following natural gas companies: Northwest Natural; Sempra Energy, Southwest Gas Corporation, Questar, and Nicor. However, initial results of accelerated age testing on repaired pipe samples showed that the high density polyethylene (HDPE) pipe patch material developed a small crack at the high stress areas surrounding the patched hole within the first 48 hours of hot water testing, indicating that the patch material has a 25-year lifespan. Based on these results, further research is continuing to develop a stronger repair patch for a satisfactory 50-year patch system. Additional tests were also conducted to evaluate whether any of the critical performance properties of the PE pipe were reduced or compromised by the repair technique. This testing validated a satisfactory 50-year patch system for the pipe.« less

Non-IgE-related diagnostic methods (LST, patch test).

PubMed

Matsumoto, Kenji

2015-01-01

Although most food allergy patients have immediate-type reactions, some have delayed-type reactions. Unlike for the detection of food-specific IgE antibody in immediate-type (IgE-mediated) food allergies, only a few tests are currently available to aid in the diagnosis of delayed-type (non-IgE-mediated) food allergies. This chapter summarizes our current understanding of one in vitro test and one in vivo test for non-IgE-mediated food allergies: the lymphocyte stimulation test (LST) and the atopy patch test (APT). Although the LST is not yet standardized, a food protein-specific LST might be a useful tool for diagnosing delayed-type food allergies, and especially those manifesting with gastrointestinal symptoms but not skin symptoms. Various remaining issues - including basophil contamination of the peripheral blood mononuclear cell fraction and lipopolysaccharide contamination of food antigen preparations - are also discussed. The APT uses an epicutaneous patch technique to occlusively apply food antigens to the skin to induce inflammatory reactions at the patch application site. Because the APT shows modest sensitivity and specificity, the clinical benefit of the APT in the diagnosis of food allergies in patients with atopic dermatitis is limited. A position paper on the APT issued by the European Academy of Allergy and Clinical Immunology/Global Allergy and Asthma European Network in 2006 is briefly summarized, and several recent APT-related topics, including APT use for the diagnosis of food protein-induced enterocolitis syndrome, are discussed. © 2015 S. Karger AG, Basel.

Development and evaluation of thermoplastic street maintenance material

NASA Technical Reports Server (NTRS)

Siemens, W. D.

1973-01-01

An all-weather permanent street patching material was investigated for flexible and rigid pavements. The economic, operational, and material requirements are discussed along with the results of field tests with various mixtures of EVA resins and asphalt. Cost analyses for thermoplastic patching methods are included.

A Multi-Threaded Cryptographic Pseudorandom Number Generator Test Suite

DTIC Science & Technology

2016-09-01

bitcoin thieves, Google releases patch. (2013, Aug. 16). SiliconANGLE. [Online]. Available: http://siliconangle.com/blog/2013/ 08/16/android-crypto-prng...flaw-aided- bitcoin -thieves-google-releases-patch/ [5] M. Gondree. (2014, Sep. 28). NPS POSIX thread pool library. [Online]. Available: https

Patch-based frame interpolation for old films via the guidance of motion paths

NASA Astrophysics Data System (ADS)

Xia, Tianran; Ding, Youdong; Yu, Bing; Huang, Xi

2018-04-01

Due to improper preservation, traditional films will appear frame loss after digital. To deal with this problem, this paper presents a new adaptive patch-based method of frame interpolation via the guidance of motion paths. Our method is divided into three steps. Firstly, we compute motion paths between two reference frames using optical flow estimation. Then, the adaptive bidirectional interpolation with holes filled is applied to generate pre-intermediate frames. Finally, using patch match to interpolate intermediate frames with the most similar patches. Since the patch match is based on the pre-intermediate frames that contain the motion paths constraint, we show a natural and inartificial frame interpolation. We test different types of old film sequences and compare with other methods, the results prove that our method has a desired performance without hole or ghost effects.

Audio-visual synchrony and spatial attention enhance processing of dynamic visual stimulation independently and in parallel: A frequency-tagging study.

PubMed

Covic, Amra; Keitel, Christian; Porcu, Emanuele; Schröger, Erich; Müller, Matthias M

2017-11-01

The neural processing of a visual stimulus can be facilitated by attending to its position or by a co-occurring auditory tone. Using frequency-tagging, we investigated whether facilitation by spatial attention and audio-visual synchrony rely on similar neural processes. Participants attended to one of two flickering Gabor patches (14.17 and 17 Hz) located in opposite lower visual fields. Gabor patches further "pulsed" (i.e. showed smooth spatial frequency variations) at distinct rates (3.14 and 3.63 Hz). Frequency-modulating an auditory stimulus at the pulse-rate of one of the visual stimuli established audio-visual synchrony. Flicker and pulsed stimulation elicited stimulus-locked rhythmic electrophysiological brain responses that allowed tracking the neural processing of simultaneously presented Gabor patches. These steady-state responses (SSRs) were quantified in the spectral domain to examine visual stimulus processing under conditions of synchronous vs. asynchronous tone presentation and when respective stimulus positions were attended vs. unattended. Strikingly, unique patterns of effects on pulse- and flicker driven SSRs indicated that spatial attention and audiovisual synchrony facilitated early visual processing in parallel and via different cortical processes. We found attention effects to resemble the classical top-down gain effect facilitating both, flicker and pulse-driven SSRs. Audio-visual synchrony, in turn, only amplified synchrony-producing stimulus aspects (i.e. pulse-driven SSRs) possibly highlighting the role of temporally co-occurring sights and sounds in bottom-up multisensory integration. Copyright © 2017 Elsevier Inc. All rights reserved.

Magnetohydrodynamic Simulations of Black Hole Accretion Flows Using PATCHWORK, a Multi-Patch, multi-code approach

NASA Astrophysics Data System (ADS)

Avara, Mark J.; Noble, Scott; Shiokawa, Hotaka; Cheng, Roseanne; Campanelli, Manuela; Krolik, Julian H.

2017-08-01

A multi-patch approach to numerical simulations of black hole accretion flows allows one to robustly match numerical grid shape and equations solved to the natural structure of the physical system. For instance, a cartesian gridded patch can be used to cover coordinate singularities on a spherical-polar grid, increasing computational efficiency and better capturing the physical system through natural symmetries. We will present early tests, initial applications, and first results from the new MHD implementation of the PATCHWORK framework.

A procedure of landscape services assessment based on mosaics of patches and boundaries.

PubMed

Martín de Agar, Pilar; Ortega, Marta; de Pablo, Carlos L

2016-09-15

We develop a procedure for assessing the environmental value of landscape mosaics that simultaneously considers the values of land use patches and the values of the boundaries between them. These boundaries indicate the ecological interactions between the patches. A landscape mosaic is defined as a set of patches and the boundaries between them and corresponds to a spatial pattern of ecological interactions. The procedure is performed in two steps: (i) an environmental assessment of land use patches by means of a function that integrates values based on the goods and services the patches provide, and (ii) an environmental valuation of mosaics using a function that integrates the environmental values of their patches and the types and frequencies of the boundaries between them. This procedure allows us to measure how changes in land uses or in their spatial arrangement cause variations in the environmental value of landscape mosaics and therefore in that of the whole landscape. The procedure was tested in the Sierra Norte of Madrid (central Spain). The results show that the environmental values of the landscape depend not only on the land use patches but also on the values associated with the pattern of the boundaries within the mosaics. The results also highlight the importance of the boundaries between land use patches as determinants of the goods and services provided by the landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bust economics: foragers choose high quality habitats in lean times

PubMed Central

Dickman, Christopher R.

2016-01-01

In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751

The influence of tyre contact patch and on the stopping distance of automotive vehicles

NASA Astrophysics Data System (ADS)

Selig, M.; Ball, A.; Ash, J.; Schmidt, K.

2012-05-01

This contribution presents the experimental tests results about the influence of the tyre contact patch on the stopping distance of automotive vehicles. The objective of the performed tests is the evaluation of the effect of tyre inflation pressure, hence the resulting tyre contact patch on the braking system and the brake distance. The conditions of the experiment are a dry and level road surface without steering inputs. To record scientific results, a brake robot system is used. The benefit of a robotic system is the elimination of the interfering variable driver, who is not able to apply the brake system at the same time with the same force. State-of-the-art data acquisition tools are used to log the data.

Blue Flag Distributed Wargaming System

DTIC Science & Technology

1992-07-01

combat simulation , and multi- site video teleconferencing (VTC). The Warrior Flag 90 feasibility demonstration was sponsored by the 4441st Tactical...provide RS-422 cross patching, loop -back and test points. At the hub six CSUs and two fiber optic modems were cabled in the normal-thru configuration...spare crypto or the fiber optic modem may be placed on-line via a patch. Loop plugs were provided for testing. Clock switches were provided to switch

Study on Chinese common allergens of contact dermatitis.

PubMed

Fan, W X; Zhao, B

1990-01-01

Patch tests were performed according to the European Standard Allergens (ESA) in 204 cases suspected of contact dermatitis. The reaction was positive in 58.33% of the cases. The common allergens were nickel (15.7%), fragrance mix (11.8%) p-phenylenediamine (8.8%), colophony (6.9%), benzocaine (6.4%), formaldehyde (5.9%), black rubber mix (4.9%), cobalt (4.4%), balsam of Peru (3.9%), potassium dichromate (3.4%), thiuram mix (2.9%) and mercapto mix (2.9%). In 85 cases of negative reaction to the European Standard Allergens, 36 were patch tested to suspected agents based on the individual case histories, of which 21 positively reacted. The common sensitizing agents were ampicillin and thiomersal. Of 204 cases, 107 were cases of facial contact dermatitis. Patch tests showed that the most common allergens were p-phenylenediamine (15.9%), nickel (13.1%) and fragrance mix (14.95%).

Habitat suitability of patch types: A case study of the Yosemite toad

Treesearch

Christina T. Liang; Thomas J. Stohlgren

2011-01-01

Understanding patch variability is crucial in understanding the spatial population structure of wildlife species, especially for rare or threatened species.We used a well-tested maximum entropy species distribution model (Maxent) to map the Yosemite toad (Anaxyrus (= Bufo) canorus) in the Sierra Nevada...

A predator equalizes rate of capture of a schooling prey in a patchy environment.

PubMed

Vijayan, Sundararaj; Kotler, Burt P; Abramsky, Zvika

2017-05-01

Prey individuals are often distributed heterogeneously in the environment, and their abundances and relative availabilities vary among patches. A foraging predator should maximize energetic gains by selectively choosing patches with higher prey density. However, catching behaviorally responsive and group-forming prey in patchy environments can be a challenge for predators. First, they have to identify the profitable patches, and second, they must manage the prey's sophisticated anti-predator behavior. Thus, the forager and its prey have to continuously adjust their behavior to that of their opponent. Given these conditions, the foraging predator's behavior should be dynamic with time in terms of foraging effort and prey capture rates across different patches. Theoretically, the allocation of its time among patches of behaviorally responsive prey should be such that it equalizes its prey capture rates across patches through time. We tested this prediction in a model system containing a predator (little egret) and group-forming prey (common gold fish) in two sets of experiments in which (1) patches (pools) contained equal numbers of prey, or in which (2) patches contained unequal densities of prey. The egret equalized the prey capture rate through time in both equal and different density experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

Complex interaction of dendritic connectivity and hierarchical patch size on biodiversity in river-like landscapes.

PubMed

Carrara, Francesco; Rinaldo, Andrea; Giometto, Andrea; Altermatt, Florian

2014-01-01

Habitat fragmentation and land use changes are causing major biodiversity losses. Connectivity of the landscape or environmental conditions alone can shape biodiversity patterns. In nature, however, local habitat characteristics are often intrinsically linked to a specific connectivity. Such a link is evident in riverine ecosystems, where hierarchical dendritic structures command related scaling on habitat capacity. We experimentally disentangled the effect of local habitat capacity (i.e., the patch size) and dendritic connectivity on biodiversity in aquatic microcosm metacommunities by suitably arranging patch sizes within river-like networks. Overall, more connected communities that occupy a central position in the network exhibited higher species richness, irrespective of patch size arrangement. High regional evenness in community composition was found only in landscapes preserving geomorphological scaling properties of patch sizes. In these landscapes, some of the rarer species sustained regionally more abundant populations better tracking their own niche requirements compared to landscapes with homogeneous patch size or landscapes with spatially uncorrelated patch size. Our analysis suggests that altering the natural link between dendritic connectivity and patch size strongly affects community composition and population persistence at multiple scales. The experimental results are demonstrating a principle that can be tested in theoretical metacommunity models and eventually be projected to real riverine ecosystems.

Design And Simulation Of Microstrip Antenna Of 2.4 GHz Using CST

NASA Astrophysics Data System (ADS)

Thakur, O. P.; Kushwaha, Alok K.

2011-12-01

This article describes the design, fabrication and testing of micro strip patch antennas operating at 2.4 GHz. Consideration is given on practical design technique, including substrate selection and antenna measurements. It is emphasised to the radiation properties of the antennas—the radiation pattern and polarization purity. A micro strip patch antenna consists of a very thin metallic patch placed a small fraction of a wavelength above a conducting ground-plane. The patch and ground-plane are separated by a dielectric. The patch conductor is normally copper and can assume any shape, but simple geometries generally are used, and this simplifies the analysis and performance prediction. The patches are usually photo etched on the dielectric substrate. The substrate is usually non-magnetic. The relative permittivity of the substrate is normally in the region between 1 and 4, which enhances the fringing fields that account for radiation, but higher values may be used in special circumstances. Due to its simple geometry, the half wave rectangular patch is the most commonly used micro strip antenna. It is characterized by its length L, width w and thickness h. The simplest method of feeding the patch is by a coplanar micro strip line, also photo etched on the substrate. Coaxial feeds are also widely used.

Haze, clouds and limited sky visibility: polarotactic orientation of crickets under difficult stimulus conditions.

PubMed

Henze, Miriam J; Labhart, Thomas

2007-09-01

Field crickets (Gryllus campestris L.) are able to detect the orientation of the electric vector (e-vector) of linearly polarized light. They presumably use this sense to exploit the celestial polarization pattern for course control or navigation. Polarization vision in crickets can be tested by eliciting a spontaneous polarotactic response. Previously, wide and 100% polarized stimuli were employed to induce this behavior. However, field crickets live on meadows where the observation of the sky is strongly limited by surrounding vegetation. Moreover, degrees of polarization (d) in the natural sky are much lower than 100%. We have therefore investigated thresholds for the behavioral response to polarized light under conditions mimicking those experienced by the insects in the field. We show that crickets are able to rely on polarized stimuli of just 1 degrees diameter. We also provide evidence that they exploit polarization down to an (average) polarization level of less than 7%, irrespective of whether the stimulus is homogeneous, such as under haze, or patched, such as a sky spotted by clouds. Our data demonstrate that crickets can rely on skylight polarization even under unfavorable celestial conditions, emphasizing the significance of polarized skylight orientation for insects.

A Case of Chromium Contact Dermatitis due to Exposure from a Golf Glove.

PubMed

Lim, Jong Ho; Kim, Hei Sung; Park, Young Min; Lee, Jun Young; Kim, Hyung Ok

2010-02-01

Chromium is a transition metal and has been shown to elicit contact dermatitis. Although leather products have been known to be the most significant source of chromium exposure these days, the majority of reports have been related to exposure from shoe products. We herein report a professional golfer who became allergic to golf gloves made of chromium-tanned leather. A 27-year-old woman golfer presented with recurrent, pruritic, erythematous plaques that had been occurring on both hands for several years. The lesions developed whenever she had worn golf gloves for an extended period of time, especially during tournament season. To identify the causative agent, patch tests were performed and the results demonstrated a strong positive reaction to potassium dichromate 0.5% and to her own glove. The amount of chromium in her golf glove was analyzed to be 308.91 ppm and based on this, a diagnosis of allergic contact dermatitis due to a chromium-tanned leather glove was made. She was treated with oral antihistamines combined with topical steroids and advised to wear chromium-free leather gloves. There has been no evidence of recurrence during a six month follow-up period.

Multicenter Patch Testing With a Resol Resin Based on Phenol and Formaldehyde Within the International Contact Dermatitis Research Group.

PubMed

Isaksson, Marléne; Ale, Iris; Andersen, Klaus; Diepgen, Thomas; Elsner, Peter; Goossens, An; Goh, Chee-Leok; Jerajani, Hemangi; Maibach, Howard; Matsunaga, Kayoko; McFadden, John; Nixon, Rosemary; Sasseville, Denis; Bruze, Magnus

2015-01-01

Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin included in most baseline patch test series. The aims of this study were to investigate the contact allergy rate to PFR-2 in an international population and to investigate associated simultaneous allergic reactions. Thirteen centers representing the International Contact Dermatitis Research Group included PFR-2 into their patch test baseline series during a period of 6 months in 2012. Of 2259 patients tested, 28 (1.2%) reacted to PFR-2. Of those 28 individuals, one had a positive reaction to formaldehyde and 2 to p-tertiary-butylphenol-formaldehyde resin. Simultaneous allergic reactions were noted to colophonium in 3, to Myroxylon pereirae in 5, and to fragrance mix I in 8. The contact allergy frequency in the tested population (1.2%) merits its inclusion into the international baseline series and possibly also into other baseline series after appropriate investigations. Significantly, overrepresented simultaneous allergic reactions were noted for M. pereirae and fragrance mix I.

Multicentre patch testing with a resol resin based on phenol and formaldehyde.

PubMed

Isaksson, Marléne; Inerot, Annica; Lidén, Carola; Matura, Mihaly; Stenberg, Berndt; Möller, Halvor; Bruze, Magnus

2011-07-01

Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin (PTBP-FR) included in most baseline patch test series. To investigate the rate of contact allergy to PFR-2 (a mixture of monomers and dimers from a resol resin based on phenol and formaldehyde) in a Swedish population, and to investigate associated simultaneous allergic reactions. Five centres representing the Swedish Contact Dermatitis Research Group included PFR-2 in their patch test baseline series for a period of 1.5 years. Of 2504 patients tested, 27 (1.1%) reacted to PFR-2. Of those 27 individuals, 2 had a positive reaction to formaldehyde and 2 to PTBP-FR. Simultaneous allergic reactions were noted to colophonium in 6, to Myroxylon pereirae in 14, and to fragrance mix I in 15. The contact allergy frequency in the tested population (1.1%) merits its inclusion in the Swedish baseline series and possibly also in other baseline series. Simultaneous allergic reactions were noted to colophonium, M. pereirae, and fragrance mix I. © 2011 John Wiley & Sons A/S.

Surface sampling techniques for 3D object inspection

NASA Astrophysics Data System (ADS)

Shih, Chihhsiong S.; Gerhardt, Lester A.

1995-03-01

While the uniform sampling method is quite popular for pointwise measurement of manufactured parts, this paper proposes three novel sampling strategies which emphasize 3D non-uniform inspection capability. They are: (a) the adaptive sampling, (b) the local adjustment sampling, and (c) the finite element centroid sampling techniques. The adaptive sampling strategy is based on a recursive surface subdivision process. Two different approaches are described for this adaptive sampling strategy. One uses triangle patches while the other uses rectangle patches. Several real world objects were tested using these two algorithms. Preliminary results show that sample points are distributed more closely around edges, corners, and vertices as desired for many classes of objects. Adaptive sampling using triangle patches is shown to generally perform better than both uniform and adaptive sampling using rectangle patches. The local adjustment sampling strategy uses a set of predefined starting points and then finds the local optimum position of each nodal point. This method approximates the object by moving the points toward object edges and corners. In a hybrid approach, uniform points sets and non-uniform points sets, first preprocessed by the adaptive sampling algorithm on a real world object were then tested using the local adjustment sampling method. The results show that the initial point sets when preprocessed by adaptive sampling using triangle patches, are moved the least amount of distance by the subsequently applied local adjustment method, again showing the superiority of this method. The finite element sampling technique samples the centroids of the surface triangle meshes produced from the finite element method. The performance of this algorithm was compared to that of the adaptive sampling using triangular patches. The adaptive sampling with triangular patches was once again shown to be better on different classes of objects.

Formulation, in vitro and in vivo evaluation of transdermal patches containing risperidone.

PubMed

Aggarwal, Geeta; Dhawan, Sanju; Hari Kumar, S L

2013-01-01

The efficacy of oral risperidone treatment in prevention of schizophrenia is well known. However, oral side effects and patient compliance is always a problem for schizophrenics. In this study, risperidone was formulated into matrix transdermal patches to overcome these problems. The formulation factors for such patches, including eudragit RL 100 and eudragit RS 100 as matrix forming polymers, olive oil, groundnut oil and jojoba oil in different concentrations as enhancers and amount of drug loaded were investigated. The transdermal patches containing risperidone were prepared by solvent casting method and characterized for physicochemical and in vitro permeation studies through excised rat skin. Among the tested preparations, formulations with 20% risperidone, 3:2 ERL 100 and ERS 100 as polymers, mixture of olive oil and jojoba oil as enhancer, exhibited greatest cumulative amount of drug permeated (1.87 ± 0.09 mg/cm(2)) in 72 h, so batch ROJ was concluded as optimized formulation and assessed for pharmacokinetic, pharmacodynamic and skin irritation potential. The pharmacokinetic characteristics of the optimized risperidone patch were determined using rabbits, while orally administered risperidone in solution was used for comparison. The calculated relative bioavailability of risperidone transdermal patch was 115.20% with prolonged release of drug. Neuroleptic efficacy of transdermal formulation was assessed by rota-rod and grip test in comparison with control and marketed oral formulations with no skin irritation. This suggests the transdermal application of risperidone holds promise for improved bioavailability and better management of schizophrenia in long-term basis.

Capuchins, space, time and memory: an experimental test of what-where-when memory in wild monkeys

PubMed Central

2016-01-01

There is considerable controversy about the existence, extent and adaptive value of integrated multimodal memory in non-human animals. Building on prior results showing that wild capuchin monkeys in Argentina appear to recall both the location and amount of food at patches they had previously visited, I tested whether they also track and use elapsed time as a basis for decisions about which feeding patches to visit. I presented them with an experimental array of eight feeding sites, at each of which food rewards increased with increasing elapsed time since the previous visit, similar to the pattern of ripe fruit accumulation in natural feeding trees. Over the course of 68 days, comprising two distinct renewal rate treatments, one group repeatedly visited sites in the feeding array, generating 212 valid choices between sites. Comparison of observations against simulated movements and multinomial statistical models shows that the monkeys' choices were most consistent with dynamic memory for elapsed time specific to each of the eight sites. Thus, it appears that capuchin monkeys possess and use integrated memories of prior food patch use, including where the patch is relative to their current location, how productive the patch is and how long it has been since they last visited the patch. Natural selection to use such integrated memories in foraging tasks may provide an ecologically relevant basis for the evolution of complex intelligence in primates. PMID:27708145

Monocular Patching May Induce Ipsilateral “Where” Spatial Bias

PubMed Central

Chen, Peii; Erdahl, Lillian; Barrett, Anna M.

2009-01-01

Spatial bias is an asymmetry of perception and/or representation of spatial information —“where” bias —, or of spatially directed actions — “aiming” bias. A monocular patch may induce contralateral “where” spatial bias (the Sprague effect; Sprague (1966) Science, 153, 1544–1547). However, an ipsilateral patch-induced spatial bias may be observed if visual occlusion results in top-down, compensatory re-allocation of spatial perceptual or representational resources toward the region of visual deprivation. Tactile distraction from a monocular patch may also contribute to an ipsilateral bias. To examine these hypotheses, neurologically normal adults bisected horizontal lines at baseline without a patch, while wearing a monocular patch, and while wearing tactile-only and visual-only monocular occlusion. We fractionated “where” and “aiming” spatial bias components using a video apparatus to reverse visual feedback for half of the test trials. The results support monocular patch-induced ipsilateral “where” spatial errors, which are not consistent with the Sprague effect. Further, the present findings suggested that the induced ipsilateral bias may be primarily induced by visual deprivation, consistent with compensatory “where” resource re-allocation. PMID:19100274

Formulation and development of a patch containing tamarind fruit extract by using the blended chitosan-starch as a rate-controlling matrix.

PubMed

Viyoch, J; Patcharaworakulchai, P; Songmek, R; Pimsan, V; Wittaya-Areekul, S

2003-06-01

A cosmetic patch containing tamarind fruit extract was formulated and developed by blending two types of natural polymers: chitosan with molecular weight of 100 000 and starch such as corn, potato or tapioca starch. The physicochemical characteristics, i.e. flexibility, colour, transparency, integrity, gloss, water sorption and bioadhesion property and the stability of the patch without tamarind content were investigated. Stability test was performed by keeping the prepared patches at 4 degrees C, at room temperature or at 45 degrees C for 2 weeks. The results showed that the formulations composed of chitosan:corn starch ratio of 4.5 : 0.5 (CC(4.5 : 0.5)) and chitosan:tapioca starch ratios of 4.5 : 0.5 (CT(4.5 : 0.5)) and 4.0 : 1.0 (CT(4 : 1)) provide patches with favourable physical characteristics, high water sorption, good bioadhesion ability and good stability. After the lyophilized tamarind extract in an amount corresponding to 5% of tartaric acid was incorporated into the formulations of CC(4.5 : 0.5), CT(4.5 : 0.5) and CT(4 : 1), the ability of the patches to adhere to skin was improved. However, after keeping the test patches at room temperature or at 45 degrees C for 6 weeks, their colours were intensified while their flexibilities and skin adhesion properties decreased. A 12-h in vitro permeation was investigated by studying the cumulative amount of tartaric acid permeated through the Silastic membrane (Dow-Coming, Midland, MI, USA). The CC(4.5 : 0.5) patch tended to give the highest amount of tartaric acid released. The release pattern of all the blended polymeric matrices was exhibited in two distinct phases: the rapid phase, where the flux averaged 3.61 microg min(-1) mm(-2); and the slow phase, where the flux averaged 1.89 microg min(-1) mm(-2).

Resource distribution influences positive edge effects in a seagrass fish.

PubMed

Macreadie, Peter I; Hindell, Jeremy S; Keough, Michael J; Jenkins, Gregory P; Connolly, Rod M

2010-07-01

According to conceptual models, the distribution of resources plays a critical role in determining how organisms distribute themselves near habitat edges. These models are frequently used to achieve a mechanistic understanding of edge effects, but because they are based predominantly on correlative studies, there is need for a demonstration of causality, which is best done through experimentation. Using artificial seagrass habitat as an experimental system, we determined a likely mechanism underpinning edge effects in a seagrass fish. To test for edge effects, we measured fish abundance at edges (0-0.5 m) and interiors (0.5-1 m) of two patch configurations: continuous (single, continuous 9-m2 patches) and patchy (four discrete 1-m2 patches within a 9-m2 area). In continuous configurations, pipefish (Stigmatopora argus) were three times more abundant at edges than interiors (positive edge effect), but in patchy configurations there was no difference. The lack of edge effect in patchy configurations might be because patchy seagrass consisted entirely of edge habitat. We then used two approaches to test whether observed edge effects in continuous configurations were caused by increased availability of food at edges. First, we estimated the abundance of the major prey of pipefish, small crustaceans, across continuous seagrass configurations. Crustacean abundances were highest at seagrass edges, where they were 16% greater than in patch interiors. Second, we supplemented interiors of continuous treatment patches with live crustaceans, while control patches were supplemented with seawater. After five hours of supplementation, numbers of pipefish were similar between edges and interiors of treatment patches, while the strong edge effects were maintained in controls. This indicated that fish were moving from patch edges to interiors in response to food supplementation. These approaches strongly suggest that a numerically dominant fish species is more abundant at seagrass edges due to greater food availability, and provide experimental support for the resource distribution model as an explanation for edge effects.

Corridor Length and Patch Colonization by a Butterfly, Junonia coenia

Treesearch

Nick Haddad

2000-01-01

Corridors have been proposed to reduce isolation and increase population persistence in fragmented landscapes, yet little research has evaluated the types of landscapes in which corridors will be most effective. I tested the hypothesis that corridors increase patch colonization by a butterfly, Junonia coenia, regardless of the butterfly's...

Energy state affects exploratory behavior of tree sparrows in a group context under differential food-patch distributions.

PubMed

Lee, Ya-Fu; Kuo, Yen-Min; Chu, Wen-Chen

2016-01-01

When facing a novel situation, animals can retreat or leave to avoid risks, but will miss potential resources and opportunities. Alternatively they may reduce environmental uncertainty by exploration, while risking no energy rewards and exposure to hazards, and use the information retrieved for subsequent decision making. When exploring, however, animals may adopt different tactics according to individual states. We tested that energy states will affect exploratory behavior by experimenting with wild-caught untrained Eurasian tree sparrows ( Passer montanus ) in fasted or fed states exploring in a novel space with hidden food supply in different patch distribution patterns. Our data revealed that fasted sparrows risked being earlier explorers more often, initiated more exploratory bouts before patches were found, and stayed longer on the ground under both patch patterns. Fasted sparrows discovered more patches and consumed more food than fed sparrows in dispersed, but not necessary so in clumped, patch patterns; whereas fed birds also increased patch finding to a certain level in dispersed patterns. Sparrows of both energy states, however, did not differ in feeding rates in either patch pattern. Exploratory behavior of tree sparrows is state-dependent, which supports our prediction that birds with an energy shortage will be risk-prone and explore more readily. Our study also indicates a game nature of tree sparrow exploratory behavior in a group context when explorers are in different energy states and are exposed to different patch distributions. Birds of lower energy state adopting an active exploring tactic may be favored by obtaining higher energy gains in dispersed patch patterns with lower patch richness. More satiated birds, however, achieved a similar feeding rate by lowered exposure time.

Conctact dermatitis: some important topics.

PubMed

Pigatto, P D

2015-11-01

Allergic contact dermatitis (ACD) is a type IV delayed hypersensitivity reaction. The gold standard for diagnosis is patch testing. The prevalence of positive patch tests in referred patients with suspected ACD ranges from 27 to 95.6%. The relationship between ACD and atopic dermatitis (AD) is complicated with conflicting reports of prevalence in the literature; however, in a patient with dermatitis not responding to traditional therapies, or with new areas of involvement, ACD should be considered as part of the work-up.

Wet Wipe Allergens: Retrospective Analysis From the North American Contact Dermatitis Group 2011-2014.

PubMed

Warshaw, Erin M; Aschenbeck, Kelly A; Zug, Kathryn A; Belsito, Donald V; Zirwas, Matthew J; Fowler, Joseph F; Taylor, James S; Sasseville, Denis; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Maibach, Howard I; Mathias, C G Toby; DeKoven, Joel G

Although there are several case reports of wet wipe-associated contact dermatitis, the prevalence of wipes as a source of allergic contact dermatitis in larger populations and the responsible allergens are largely unknown. The aim of the study was to determine the prevalence of wet wipes as a source of contact allergy and the most commonly associated allergens in a North American tertiary referral patch test population. Data collected from 2011 to 2014 by the North American Contact Dermatitis Group was used to conduct a retrospective cross-sectional analysis of patient demographics and patch test results associated with the triple-digit source code for "wet wipe." Of the 9037 patients patch tested during the study period, 79 (0.9%) had a positive patch test reaction to an allergen identified with a wet wipe source. The most commonly associated allergens were preservatives, including the following: methylisothiazolinone (MI) (59.0%), methylchloroisothiazolinone (MCI)/MI (35.6%), bronopol (2-bromo-2-nitropropane-1,3-diol) (27.4%), and iodopropynyl butylcarbamate (12.3%). Fragrance (combined) represented 12.3%. Anal/genital dermatitis was 15 times more likely (P < 0.0001) in those with wet wipe allergy. More than 92% of patients with wipe-associated contact allergy had their contact allergens detected by the North American Contact Dermatitis Group screening series. Wet wipes are an important source of contact allergy. Preservatives are the main allergens, especially isothiazolinones.

Contact allergy to epoxy resin: risk occupations and consequences.

PubMed

Bangsgaard, Nannie; Thyssen, Jacob Pontoppidan; Menné, Torkil; Andersen, Klaus Ejner; Mortz, Charlotte G; Paulsen, Evy; Sommerlund, Mette; Veien, Niels Kren; Laurberg, Grete; Kaaber, Knud; Thormann, Jens; Andersen, Bo Lasthein; Danielsen, Anne; Avnstorp, Christian; Kristensen, Berit; Kristensen, Ove; Vissing, Susanne; Nielsen, Niels Henrik; Johansen, Jeanne Duus

2012-08-01

Epoxy resin monomers are strong skin sensitizers that are widely used in industrial sectors. In Denmark, the law stipulates that workers must undergo a course on safe handling of epoxy resins prior to occupational exposure, but the effectiveness of this initiative is largely unknown. To evaluate the prevalence of contact allergy to epoxy resin monomer (diglycidyl ether of bisphenol A; MW 340) among patients with suspected contact dermatitis and relate this to occupation and work-related consequences. The dataset comprised 20 808 consecutive dermatitis patients patch tested during 2005-2009. All patients with an epoxy resin-positive patch test were sent a questionnaire. A positive patch test reaction to epoxy resin was found in 275 patients (1.3%), with a higher proportion in men (1.9%) than in women (1.0%). The prevalence of sensitization to epoxy resin remained stable over the study period. Of the patients with an epoxy resin-positive patch test, 71% returned a questionnaire; 95 patients had worked with epoxy resin in the occupational setting, and, of these, one-third did not use protective gloves and only 50.5% (48) had participated in an educational programme. The 1% prevalence of epoxy resin contact allergy is equivalent to reports from other countries. The high occurrence of epoxy resin exposure at work, and the limited use of protective measures, indicate that reinforcement of the law is required. © 2012 John Wiley & Sons A/S.

Footwear contact dermatitis from dimethyl fumarate.

PubMed

Švecová, Danka; Šimaljakova, Maria; Doležalová, Anna

2013-07-01

Dimethyl fumarate (DMF) is an effective inhibitor of mold growth. In very low concentrations, DMF is a potent sensitizer that can cause severe allergic contact dermatitis (ACD). It has been identified as the agent responsible for furniture contact dermatitis in Europe. The aim of this study was to evaluate patients in Slovakia with footwear ACD associated with DMF, with regard to clinical manifestations, patch test results, and results of chemical analysis of their footwear. Nine patients with suspected footwear contact dermatitis underwent patch testing with the following allergens: samples of their own footwear, commercial DMF, the European baseline, shoe screening, textile and leather dye screening, and industrial biocides series. The results were recorded according to international guidelines. The content of DMF in footwear and anti-mold sachets was analyzed using gas chromatography and mass spectrometry. Acute ACD was observed in nine Caucasian female patients. All patients developed delayed sensitization, as demonstrated by positive patch testing using textile footwear lining. Seven patients were patch tested with 0.1% DMF, and all seven were positive. Chemical analysis of available footwear showed that DMF was present in very high concentrations (25-80 mg/Kg). Dimethyl fumarate is a new footwear allergen and was responsible for severe ACD in our patients. To avoid an increase in the number of cases, the already approved European preventive measures should be accepted and commonly employed. © 2013 The International Society of Dermatology.

Image-Based Patient-Specific Ventricle Models with Fluid-Structure Interaction for Cardiac Function Assessment and Surgical Design Optimization

PubMed Central

Tang, Dalin; Yang, Chun; Geva, Tal; del Nido, Pedro J.

2010-01-01

Recent advances in medical imaging technology and computational modeling techniques are making it possible that patient-specific computational ventricle models be constructed and used to test surgical hypotheses and replace empirical and often risky clinical experimentation to examine the efficiency and suitability of various reconstructive procedures in diseased hearts. In this paper, we provide a brief review on recent development in ventricle modeling and its potential application in surgical planning and management of tetralogy of Fallot (ToF) patients. Aspects of data acquisition, model selection and construction, tissue material properties, ventricle layer structure and tissue fiber orientations, pressure condition, model validation and virtual surgery procedures (changing patient-specific ventricle data and perform computer simulation) were reviewed. Results from a case study using patient-specific cardiac magnetic resonance (CMR) imaging and right/left ventricle and patch (RV/LV/Patch) combination model with fluid-structure interactions (FSI) were reported. The models were used to evaluate and optimize human pulmonary valve replacement/insertion (PVR) surgical procedure and patch design and test a surgical hypothesis that PVR with small patch and aggressive scar tissue trimming in PVR surgery may lead to improved recovery of RV function and reduced stress/strain conditions in the patch area. PMID:21344066

Biocompatibility evaluation of cigarette and carbon papers used in repair of traumatic tympanic membrane perforations: experimental study.

PubMed

Altuntaş, Emine Elif; Sümer, Zeynep

2013-01-01

The purposes of this study were to investigate the biocompatibility of two different paper patches (carbon and cigarette papers) and compare the adhesion and proliferation features of L929 fibroblast cells by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT Test) test and scanning electron microscopy (SEM). In this study, time-dependent cytotoxic effects of cigarette and carbon papers used in repairing small traumatic TM perforations were investigated in vitro by using MTT test. And also adhesion and spreading of cells over disk surface were observed by SEM. Cytotoxicity test carried out by MTT analysis on leakage products collected from two types of paper patches at the end of 24 and 48 h revealed no cytotoxicity (P > 0.05). In SEM studies, it was observed that cells started to proliferate over disk surface as a result of 48-h incubation, and SEM revealed that the cell proliferation over cigarette paper was more compared to the one over carbon paper. We believe that this is the first study where biocompatibility and adhesion features of carbon and cigarette paper have been studied by using L929 fibroblast cell culture. As a result, biocompatibility of cigarette paper and also whether cigarette paper was superior to carbon paper in cell attachment and biocompatibility were studied. It was found, by MTT test and SEM test, that cigarette paper had a higher biocompatibility and cell attachment, and thus cigarette paper should be the patch to be preferred in cases where TM perforations are repaired by paper-patch method.

Safety and efficacy of personal care products containing colloidal oatmeal.

PubMed

Criquet, Maryline; Roure, Romain; Dayan, Liliane; Nollent, Virginie; Bertin, Christiane

2012-01-01

Colloidal oatmeal is a natural ingredient used in the formulation of a range of personal care products for relief of skin dryness and itchiness. It is also used as an adjunctive product in atopic dermatitis. The safety of personal care products used on vulnerable skin is of particular importance and the risk of developing further skin irritations and/or allergies should be minimized. In a series of studies, we tested the safety of personal care products containing oatmeal (creams, cleansers, lotions) by assessing their irritant/allergenic potential on repeat insult patch testing, in safety-in-use and ocular studies using subjects with nonsensitive and sensitive skin. We also tested the skin moisturizing and repair properties of an oatmeal-containing skin care product for dry skin. We found that oatmeal-containing personal care products had very low irritant potential as well as a very low allergenic sensitization potential. Low-level reactions were documented in 1.0% of subjects during the induction phase of repeat insult patch testing; one of 2291 subjects developed a persistent but doubtful low-level reaction involving edema during the challenge phase in repeat insult patch testing. No allergies were reported by 80 subjects after patch testing after in-use application. Sustained skin moisturizing was documented in subjects with dry skin that lasted up to 2 weeks after product discontinuation. Our results demonstrate that colloidal oatmeal is a safe and effective ingredient in personal care products. No allergies were reported by consumers of 445,820 products sold during a 3-year period.

Safety and efficacy of personal care products containing colloidal oatmeal

PubMed Central

Criquet, Maryline; Roure, Romain; Dayan, Liliane; Nollent, Virginie; Bertin, Christiane

2012-01-01

Background Colloidal oatmeal is a natural ingredient used in the formulation of a range of personal care products for relief of skin dryness and itchiness. It is also used as an adjunctive product in atopic dermatitis. The safety of personal care products used on vulnerable skin is of particular importance and the risk of developing further skin irritations and/or allergies should be minimized. Methods In a series of studies, we tested the safety of personal care products containing oatmeal (creams, cleansers, lotions) by assessing their irritant/allergenic potential on repeat insult patch testing, in safety-in-use and ocular studies using subjects with nonsensitive and sensitive skin. We also tested the skin moisturizing and repair properties of an oatmeal-containing skin care product for dry skin. Results We found that oatmeal-containing personal care products had very low irritant potential as well as a very low allergenic sensitization potential. Low-level reactions were documented in 1.0% of subjects during the induction phase of repeat insult patch testing; one of 2291 subjects developed a persistent but doubtful low-level reaction involving edema during the challenge phase in repeat insult patch testing. No allergies were reported by 80 subjects after patch testing after in-use application. Sustained skin moisturizing was documented in subjects with dry skin that lasted up to 2 weeks after product discontinuation. Conclusion Our results demonstrate that colloidal oatmeal is a safe and effective ingredient in personal care products. No allergies were reported by consumers of 445,820 products sold during a 3-year period. PMID:23204849

Nicotine patches and quitline counseling to help hospitalized smokers stay quit: study protocol for a randomized controlled trial.

PubMed

Cummins, Sharon; Zhu, Shu-Hong; Gamst, Anthony; Kirby, Carrie; Brandstein, Kendra; Klonoff-Cohen, Hillary; Chaplin, Edward; Morris, Timothy; Seymann, Gregory; Lee, Joshua

2012-08-01

Hospitalized smokers often quit smoking, voluntarily or involuntarily; most relapse soon after discharge. Extended follow-up counseling can help prevent relapse. However, it is difficult for hospitals to provide follow-up and smokers rarely leave the hospital with quitting aids (for example, nicotine patches). This study aims to test a practical model in which hospitals work with a state cessation quitline. Hospital staff briefly intervene with smokers at bedside and refer them to the quitline. Depending on assigned condition, smokers may receive nicotine patches at discharge or extended quitline telephone counseling post-discharge. This project establishes a practical model that lends itself to broader dissemination, while testing the effectiveness of the interventions in a rigorous randomized trial. This randomized clinical trial (N = 1,640) tests the effect of two interventions on long-term quit rates of hospitalized smokers in a 2 x 2 factorial design. The interventions are (1) nicotine patches (eight-week, step down program) dispensed at discharge and (2) proactive telephone counseling provided by the state quitline after discharge. Subjects are randomly assigned into: usual care, nicotine patches, telephone counseling, or both patches and counseling. It is hypothesized that patches and counseling have independent effects and their combined effect is greater than either alone. The primary outcome measure is thirty-day abstinence at six months; a secondary outcome is biochemically validated smoking status. Cost-effectiveness analysis is conducted to compare each intervention condition (patch alone, counseling alone, and combined interventions) against the usual care condition. Further, this study examines whether smokers' medical diagnosis is a moderator of treatment effect. Generalized linear (binomial) mixed models will be used to study the effect of treatment on abstinence rates. Clustering is accounted for with hospital-specific random effects. If this model is effective, quitlines across the U.S. could work with interested hospitals to set up similar systems. Hospital accreditation standards related to tobacco cessation performance measures require follow-up after discharge and provide additional incentive for hospitals to work with quitlines. The ubiquity of quitlines, combined with the consistency of quitline counseling delivery as centralized state operations, make this partnership attractive. Smoking cessation in hospitalized smokers NCT01289275. Date of registration February 1, 2011; date of first patient August 3, 2011.

Existence of multiple receptors in single neurons: responses of single bullfrog olfactory neurons to many cAMP-dependent and independent odorants.

PubMed

Kashiwayanagi, M; Shimano, K; Kurihara, K

1996-11-04

The responses of single bullfrog olfactory neurons to various odorants were measured with the whole-cell patch clamp which offers direct information on cellular events and with the ciliary recording technique to obtain stable quantitative data from many neurons. A large portion of single olfactory neurons (about 64% and 79% in the whole-cell recording and in the ciliary recording, respectively) responded to many odorants with quite diverse molecular structures, including both odorants previously indicated to be cAMP-dependent (increasing) and independent odorants. One odorant elicited a response in many cells; e.g. hedione and citralva elicited the response in 100% and 92% of total neurons examined with the ciliary recording technique. To confirm that a single neuron carries different receptors or transduction pathways, the cross-adaptation technique was applied to single neurons. Application of hedione to a single neuron after desensitization of the current in response to lyral or citralva induced an inward current with a similar magnitude to that applied alone. It was suggested that most single olfactory neurons carry multiple receptors and at least dual transduction pathways.

Surgery-Related Contact Dermatitis: A Review of Potential Irritants and Allergens.

PubMed

Cook, Kevin A; Kelso, John M

Surgical procedures utilize an increasing number of medical products including antiseptics, anesthetics, gloves, suture materials, tissue adhesives, topical antibiotics, and bandages. Many of these products have irritant potential. Allergic contact dermatitis has also been reported. This review covers preoperative, operative, and postoperative exposures that may result in contact dermatitis. Testing with standard patch panels such as T.R.U.E. Test and the North American Contact Dermatitis Group 65 allergen series does not evaluate for all relevant contactants. A thorough understanding of potential exposures is vital to effectively evaluate a patient with surgery-related contact dermatitis. A systematic approach is needed to ensure that standard patch panels and supplementary patches adequately address each encountered contactant. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Evaluation of a mucoadhesive buccal patch for delivery of peptides: in vitro screening of bioadhesion.

PubMed

Li, C; Bhatt, P P; Johnston, T P

1998-10-01

We have assessed the bioadhesive properties of several different mucoadhesive buccal patches. The patches consisted of custom coformulations of silicone polymers and Carbopol 974P. The contact angle of water was measured for each of the test formulations, using an ophthalmic shadow scope. The corresponding work of adhesion between the water and the patches (W1), and between the patches and freshly-excised rabbit buccal mucosa (W2) was then calculated, using a modification of Dupre's equation. The bioadhesive strength between the patches and excised rabbit buccal mucosa was also assessed. The results of the contact-angle measurements indicated that the contact angle decreased with an increase in the amount of Carbopol in the formulation. Additionally, the calculated values of both W1 and W2 increased with an increase in the amount of Carbopol in the buccal-patch formulations. A correlation (r not equal to 0.9808) was found between the measured contact angle and the calculated values for W2. The direct measurement of the force required to separate a buccal patch from excised rabbit buccal mucosa with the INSTRON demonstrated that the adhesive strength increased with an increase in the amount of Carbopol. This preliminary study has shown that the measurement of contact angles alone may provide a useful technique for estimating the work of adhesion, and may serve as a convenient and rapid screening procedure to identify potential mucoadhesive buccal-patch formulations.

Predation and landscape characteristics independently affect reef fish community organization.

PubMed

Stier, Adrian C; Hanson, Katharine M; Holbrook, Sally J; Schmitt, Russell J; Brooks, Andrew J

2014-05-01

Trophic island biogeography theory predicts that the effects of predators on prey diversity are context dependent in heterogeneous landscapes. Specifically, models predict that the positive effect of habitat area on prey diversity should decline in the presence of predators, and that predators should modify the partitioning of alpha and beta diversity across patchy landscapes. However, experimental tests of the predicted context dependency in top-down control remain limited. Using a factorial field experiment we quantify the effects of a focal predatory fish species (grouper) and habitat characteristics (patch size, fragmentation) on the partitioning of diversity and assembly of coral reef fish communities. We found independent effects of groupers and patch characteristics on prey communities. Groupers reduced prey abundance by 50% and gamma diversity by 45%, with a disproportionate removal of rare species relative to common species (64% and 36% reduction, respectively; an oddity effect). Further, there was a 77% reduction in beta diversity. Null model analysis demonstrated that groupers increased the importance of stochastic community assembly relative to patches without groupers. With regard to patch size, larger patches contained more fishes, but a doubling of patch size led to a modest (36%) increase in prey abundance. Patch size had no effect on prey diversity; however, fragmented patches had 50% higher species richness and modified species composition relative to unfragmented patches. Our findings suggest two different pathways (i.e., habitat or predator shifts) by which natural and/or anthropogenic processes can drive variation in fish biodiversity and community assembly.

Knowledge-based design of generate-and-patch problem solvers that solve global resource assignment problems

NASA Technical Reports Server (NTRS)

Voigt, Kerstin

1992-01-01

We present MENDER, a knowledge based system that implements software design techniques that are specialized to automatically compile generate-and-patch problem solvers that satisfy global resource assignments problems. We provide empirical evidence of the superior performance of generate-and-patch over generate-and-test: even with constrained generation, for a global constraint in the domain of '2D-floorplanning'. For a second constraint in '2D-floorplanning' we show that even when it is possible to incorporate the constraint into a constrained generator, a generate-and-patch problem solver may satisfy the constraint more rapidly. We also briefly summarize how an extended version of our system applies to a constraint in the domain of 'multiprocessor scheduling'.

Sensitization to fragrance materials in Indonesian cosmetics.

PubMed

Roesyanto-Mahadi, I D; Geursen-Reitsma, A M; van Joost, T; van den Akker, T W

1990-04-01

2 different groups of patients were patch tested with 2 test series (A and B) containing extracts of fragrance raw materials, traditionally used in Indonesian cosmetics. Series A consisted of diluted extracts of commercially available Indonesian fragrances. Series B consisted of extracts prepared in our department from corresponding indigenous flowers and fruits. Group 1 consisted of 32 patients positive to fragrance-mix, of whom 8 (25%) had positive tests to 1 or more of the different extracts of fragrance raw materials. Reactions were observed to extracts of: Rosa hybrida Hort (7); Canangium odoratum Baill (5); Citrus aurantifolia Swingle (4); Jasminum sambac Ait (2). 6 of the 8 patients had reactions to 1 or more of the components of fragrance-mix: oakmoss (3); cinnamic alcohol (2), isoeugenol (1); cinnamic aldehyde (1) and geraniol (1). Group 2 consisted of 159 patients patch tested on suspicion of contact dermatitis, who were fragrance-mix negative. Only 2 (1.2%) had a positive patch test to the extracts of fragrance raw materials. Specimens taken (as is) from the flowers and citrus fruits (being the basis sources of the fragrance raw materials) were less antigenic. The use of additional test series in Indonesia to detect allergy to traditional cosmetics and perfumes merits further investigation.

A Randomized Trial Comparing Part-time Patching with Observation for Children 3–10 Years Old with Intermittent Exotropia

PubMed Central

Cotter, Susan A.; Mohney, Brian G.; Chandler, Danielle L.; Holmes, Jonathan M.; Repka, Michael X.; Melia, Michele; Wallace, David K.; Beck, Roy W.; Birch, Eileen E.; Kraker, Raymond T.; Tamkins, Susanna M.; Miller, Aaron M.; Sala, Nicholas A.; Glaser, Stephen R.

2014-01-01

Objective To determine the effectiveness of prescribed part-time patching for treatment of intermittent exotropia in children Design Multicenter, randomized clinical trial Participants Three hundred fifty-eight children aged 3 to < 11 years old with previously untreated (except for refractive correction) intermittent exotropia (IXT) and near stereoacuity of 400 arcsec or better were enrolled. Intermittent exotropia met the following criteria: 1) constant or intermittent exotropia at distance and either intermittent exotropia or exophoria at near; 2) exodeviation (tropia or phoria) of at least 15 prism diopters (Δ) at distance or near by prism and alternate cover test (PACT); and 3) exodeviation of at least 10Δ at distance by PACT. Methods Participants were randomly assigned to either observation (no treatment for 6 months) or patching for 3 hours per day for 5 months, with a 1-month washout period of no patching before the 6-month primary outcome exam. Main Outcome Measure The primary outcome was deterioration at either the 3-month or the 6-month follow-up visit, defined as: 1) constant exotropia measuring at least 10Δ at distance and near by simultaneous prism and cover test, and/or 2) near stereoacuity decreased by at least 2 octaves from baseline, both assessed by a masked examiner and confirmed by a retest. Participants who were prescribed any non-randomized treatment without first meeting either deterioration criteria were also counted as having deteriorated. Results Of the 324 (91%) participants completing the 6-month primary outcome exam, deterioration occurred in 10 (6.1%) of the 165 participants in the observation group (3 of these 10 started treatment without meeting deterioration criteria) and in 1 (0.6%) of the 159 participants in the part-time patching group (difference = 5.4%, lower limit of one-sided exact 95% confidence interval = 2.0%; p value from one-sided hypothesis test = 0.004). Conclusion Deterioration of previously untreated childhood IXT over a 6-month period is uncommon with or without patching treatment. Although there is a slightly lower deterioration rate with patching, both management approaches are reasonable for treating 3 to 10 year olds with IXT. PMID:25234012

Allergy to oxidized limonene and linalool is frequent in the U.K.

PubMed

Audrain, H; Kenward, C; Lovell, C R; Green, C; Ormerod, A D; Sansom, J; Chowdhury, M M U; Cooper, S M; Johnston, G A; Wilkinson, M; King, C; Stone, N; Horne, H L; Holden, C R; Wakelin, S; Buckley, D A

2014-08-01

The oxidized forms of the fragrance terpenes limonene and linalool are known to cause allergic contact dermatitis. Significant rates of contact allergy to these fragrances have been reported in European studies and in a recent worldwide study. Patch testing to oxidized terpenes is not routinely carried out either in the U.K. or in other centres internationally. To investigate the prevalence of contact allergy to oxidized limonene and linalool in the U.K. Between 1 August 2011 and 31 December 2012, 4731 consecutive patients in 13 U.K. dermatology departments were tested for hydroperoxides of limonene 0·3% pet., hydroperoxides of linalool 1·0% pet., stabilized limonene 10·0% pet. and stabilized linalool 10·0% pet. Doubtful (?+) and equivocal (±) reactions were grouped together as irritant reactions. Two hundred and thirty-seven patients (5·0%) had a positive patch test reaction to hydroperoxides of limonene 0·3% pet. and 281 (5·9%) to hydroperoxides of linalool 1·0% pet. Irritant reactions to one or both oxidized terpenes were found in 242 patients (7·3%). Eleven patients (0·2%) had a positive patch test reaction to the stabilized terpenes alone. This large, multicentre U.K. audit shows a significant rate of allergy to the hydroperoxides of limonene and linalool plus a high rate of irritant reactions. Testing to the oxidized forms alone captures the majority (97·0%; 411 of 422) of positive reactions; testing to nonoxidized terpenes appears to be less useful. We recommend that the hydroperoxides of limonene and linalool be added to an extended baseline patch test series. © 2014 British Association of Dermatologists.

Positive relationship-intensity of response to p-phenylenediamine on patch testing and cross-reactions with related allergens.

PubMed

Thomas, Bjorn R; White, Ian R; McFadden, John P; Banerjee, Piu

2014-08-01

Hair dye exposure is the most common cause of sensitization to p-phenylenediamine (PPD). Cross-reactions with structurally related allergens occur. It is suggested that a stronger patch test reaction (3+ rather than 1+) to PPD (usually tested as 1% petrolatum) is associated with an increased propensity for cross-reactions. In this article we will demonstrate this association. Of 230 patients with allergic reactions to PPD on patch testing identified during 2007-2012 from clinical records, notes for 221 were available for review. Data were collected regarding age, sex, and grade of reaction [International Contact Dermatitis Research Group (ICDRG) criteria] to PPD. Cross-reactions with the following allergens, found in our baseline series, were recorded: Disperse Yellow 3, N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and caine mix. Having excluded 23 doubtful reactions, the reactions from 198 patients were further considered. Of the patients, 75.3% (n = 149) were female, and the mean age was 48.6 years (12-82 years). Of the patients allergic to PPD, 16.6% (n = 33) showed cross-reactions with one or more related allergens. Cross-reactions were seen in 16% with a grade of 1+, 14.5% with a grade of 2+, 28.6% with a grade of 3+ when PPD was tested 1% pet., and 50.0% when PPD was tested at 0.1-0.001%, arbitrarily considered to be 4+ (p = 0.02; Cramér's V = 0.23). An increasing likelihood of reactions to Disperse Yellow 3, IPPD or caine mix was seen with increasing strength of patch test reaction to PPD. The clinical relevance of these cross-reactions is unclear. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of nanotechnologies-based devices on postural control in healthy subjects.

PubMed

Malchiodi Albedi, Giovanna; Corna, Stefano; Aspesi, Valentina; Clerici, Daniela; Parisio, Cinzia; Seitanidis, Jonathan; Cau, Nicola; Brugliera, Luigia; Capodaglio, Paolo

2017-09-05

The aim of the present preliminary randomized controlled study was to ascertain whether the use of newly developed nanotechnologies-based patches can influence posture control of healthy subjects. Thirty healthy female subjects (age 39.4 years, BMI 22.74 kg/m2) were randomly assigned to two groups: one with active patches and a control group with sham patches. Two patches were applied with a tape: one on the subject's sternum and the other on the C7 apophysis. Body sway during quiet upright stance was recorded with a dynamometric platform. Each subject was tested under two visual conditions, eyes open and closed. We used a blocked stratified randomization procedure conducted by a third party. Subjects wearing the sham patches showed a significant increase of the centre of pressure sway area after 4 hours when they performed the habitual moderate-intensity work activities. In the active patch group, a decrease of the sway path was evident, providing evidence of an enhanced balance control. Our preliminary findings on healthy subjects indicate that nanotechnological devices generating ultra-low electromagnetic fields can improve posture control.

Contact allergy to air-exposed geraniol: clinical observations and report of 14 cases.

PubMed

Hagvall, Lina; Karlberg, Ann-Therese; Christensson, Johanna Bråred

2012-07-01

The fragrance terpene geraniol forms sensitizing compounds via autoxidation and skin metabolism. Geranial and neral, the two isomers of citral, are the major haptens formed in both of these activation pathways. To investigate whether testing with oxidized geraniol detects more cases of contact allergy than testing with pure geraniol. The pattern of reactions to pure and oxidized geraniol, and metabolites/autoxidation products, was studied to investigate the importance of autoxidation or cutaneous metabolism in contact allergy to geraniol. Pure and oxidized geraniol were tested at 2.0% petrolatum in 2227 and 2179 consecutive patients, respectively. In parallel, geranial, neral and citral were tested in 2152, 1626 and 1055 consecutive patients, respectively. Pure and oxidized geraniol gave positive patch test reactions in 0.13% and 0.55% of the patients, respectively. Eight of 11 patients with positive patch test reactions to oxidized geraniol also reacted to citral or its components. Relevance for the positive patch test reactions in relation to the patients' dermatitis was found in 11 of 14 cases. Testing with oxidized geraniol could detect more cases of contact allergy to geraniol. The reaction pattern of the 14 cases presented indicates that both autoxidation and metabolism could be important in sensitization to geraniol. © 2012 John Wiley & Sons A/S.

Exploring Proficiency-Based vs. Performance-Based Items with Elicited Imitation Assessment

ERIC Educational Resources Information Center

Cox, Troy L.; Bown, Jennifer; Burdis, Jacob

2015-01-01

This study investigates the effect of proficiency- vs. performance-based elicited imitation (EI) assessment. EI requires test-takers to repeat sentences in the target language. The accuracy at which test-takers are able to repeat sentences highly correlates with test-takers' language proficiency. However, in EI, the factors that render an item…

The influence of body mass index on skin susceptibility to sodium lauryl sulphate.

PubMed

Löffler, H; Aramaki, J U N; Effendy, Isaak

2002-02-01

The influence of nutrition on the physiological functions of man is well studied. Numerous diseases can be exacerbated by obesity. However, it has not yet been determined whether body weight and body mass index (BMI), as an indicator of a high body fat store, can influence skin sensitivity. This study investigates the correlation between body mass index and the epidermal functions, evaluated by bioengineering methods, before and after an irritant patch test with sodium lauryl sulphate (SLS). Epidermal functions were evaluated using an evaporimeter, chromameter and laser-Doppler-flowmeter. Patch testing was conducted for 48 h with two different concentrations of SLS (0.25% and 0.5%) on the forearms of healthy volunteers. Measurements were performed 24h after patch removal. Obese individuals showed significantly increased transepidermal water loss (TEWL), skin blood flow and skin colour (red) as compared to a control group. However, the degree of skin sensitivity to SLS was not correlated with BMI. Basal biophysical parameters of the skin are primarily correlated with the BMI. This may be caused by obesity-induced physiological changes, e.g. increased sweat gland activity, high blood pressure and physiological temperature-regulating system. The epidermal barrier function, as evaluated after SLS patch testing is, however, not correlated with a high BMI, indicating a normal skin barrier.

A case of acute generalized exanthematous pustulosis due to amoxicillin-clavulanate with multiple positivity to beta-lactam patch testing.

PubMed

Bomarrito, L; Zisa, G; Delrosso, G; Farinelli, P; Galimberti, M

2013-09-01

We present a case of acute generalized exanthematous pustolosis (AGEP) induced by amoxicillin-clavulanate. Clinical diagnosis was confirmed by symptoms presentation and  histological features (Euroscar score point compatible with definite diagnosis). Patch testing performer six months later confirmed sensitization to the culprit drug and showed positivity also to other beta-lactam antibiotics (penicillin G and cephalexin). We believe that a T cell delayed response to betalactams common ring could be involved.

Cross-reactions to desoximetasone and mometasone furoate in a patient with multiple topical corticosteroid allergies.

PubMed

Donovan, Jeffrey C H; Dekoven, Joel G

2006-09-01

A 60-year-old man developed a bullous contact dermatitis after topical corticosteroid treatment of dermatitis on his lower leg. Subsequent patch testing showed cross-reactions to numerous group B and group D corticosteroids as well as cross-reactions to group C desoximetasone and group D1 mometasone furoate. His patch-test result was negative for the group A corticosteroids hydrocortisone and tixocortol pivalate. We discuss the uncommon finding of cross-reactions to desoximetasone and mometasone furoate.

Ignition potential of muzzle-loading firearms: An exploratory investigation

Treesearch

David V. Haston; Mark A. Finney; Andy Horcher; Philip A. Yates; Kahlil Detrich

2009-01-01

The National Technology and Development Program of the Forest Service, U.S. Department of Agriculture, was asked to conduct an exploratory study on the ignition potential of muzzle-loading firearms. The five independent variables investigated include projectile type, powder type, powder load, patch thickness, and patch lubricant treatment. Indoor testing was performed...

Superconducting antennas for telecommunication applications based on dual mode cross slotted patches

NASA Astrophysics Data System (ADS)

Cassinese, A.; Barra, M.; Fragalà, I.; Kusunoki, M.; Malandrino, G.; Nakagawa, T.; Perdicaro, L. M. S.; Sato, K.; Ohshima, S.; Vaglio, R.

2002-08-01

Dual mode devices based on high temperature superconducting films represent an interesting class for telecommunication applications since they combine a miniaturized size with a good power handling. Here we report on a novel compact antenna obtained by crossing a square patch with two or more slots. The proposed design has an antenna size reduction of about 40% as compared to the conventional square patch microstrip antennas. Single patch antenna both with linear (LP) and circular (CP) polarization operating in the X-band have been designed and tested at prototype level. They are realized by using double sided (YBa 2Cu 3O 7- x) YBCO and Tl 2Ba 2Ca 1Cu 2O 8 (Tl-2212) superconducting films grown on MgO substrates and tested with a portable cryocooler. They showed at T=77 K a return loss <25 dB and a power handling of 23 dBm. Exemplary 16 elements arrays LP antennas operating in the X band have been also realized by using YBCO film grown on 2 ″ diameter MgO substrate.

Development of procedures for early screening of smoking cessation medications in humans.

PubMed

Perkins, K A; Lerman, C; Stitzer, Ml; Fonte, C A; Briski, J L; Scott, J A; Chengappa, K N R

2008-08-01

Candidate medications for smoking cessation may be screened more efficiently if initial evaluations in humans combine the practical advantages of laboratory studies with the clinical validity of clinical trials, such as by increasing participants' "quit motivation" during brief testing. We manipulated "intrinsic" quit motivation by recruiting smokers who either did intend to quit soon ("treatment seekers," N = 47) or did not ("nonseekers," N = 93), and "extrinsic" quit motivation by providing or not providing reinforcement for abstinence ($12/day). All the subjects smoked as they would usually do during weeks 1 and 3, and tried to quit during weeks 2 and 4 using either a nicotine patch (21 mg) or a placebo patch, in accordance with the crossover design of the study. The nicotine patch increased abstinence in treatment seekers but not in nonseekers. Reinforcement had a main effect on abstinence but did not moderate the effects of the nicotine patch or treatment-seeking status. Intrinsic, but not extrinsic, quit motivation of participants may enhance the validity of brief tests of medication efficacy for smoking cessation.

Allergic contact reaction to dexpanthenol: lymphocyte transformation test and evidence for microsomal-dependent metabolism of the allergen.

PubMed

Hahn, C; Röseler, S; Fritzsche, R; Schneider, R; Merk, H F

1993-02-01

In a patient with contact dermatitis, dexpanthenol was found to be the causative allergen. There was a positive reaction to dexpanthenol on patch testing. Controls did not show any positive reactions to dexpanthenol on patch testing. Additionally, an LTT was performed. After preincubation with dexpanthenol-modified microsomes, we observed an increase in lymphocyte proliferation to dexpanthenol, in comparison to dexpanthenol without microsomes, suggesting that microsomal metabolism plays a rôle in the pathogenesis of dexpanthenol sensitization, because microsomes are known to possess drug metabolizing enzymes such as cytochrome P450.

Lidocaine self-sacrificially improves the skin permeation of the acidic and poorly water-soluble drug etodolac via its transformation into an ionic liquid.

PubMed

Miwa, Yasushi; Hamamoto, Hidetoshi; Ishida, Tatsuhiro

2016-05-01

Poor transdermal penetration of active pharmaceutical ingredients (APIs) impairs both bioavailability and therapeutic benefits and is a major challenge in the development of transdermal drug delivery systems. Here, we transformed a poorly water-soluble drug, etodolac, into an ionic liquid in order to improve its hydrophobicity, hydrophilicity and skin permeability. The ionic liquid was prepared by mixing etodolac with lidocaine (1:1, mol/mol). Both the free drug and the transformed ionic liquid were characterized by differential scanning colorimetry (DSC), infrared spectroscopy (IR), and saturation concentration measurements. In addition, in vitro skin-permeation testing was carried out via an ionic liquid-containing patch (Etoreat patch). The lidocaine and etodolac in ionic liquid form led to a relatively lower melting point than either lidocaine or etodolac alone, and this improved the lipophilicity/hydrophilicity of etodolac. In vitro skin-permeation testing demonstrated that the Etoreat patch significantly increased the skin permeation of etodolac (9.3-fold) compared with an etodolac alone patch, although an Etoreat patch did not increase the skin permeation of lidocaine, which was consistent with the results when using a lidocaine alone patch. Lidocaine appeared to self-sacrificially improve the skin permeation of etodolac via its transformation into an ionic liquid. The data suggest that ionic liquids composed of approved drugs may substantially expand the formulation preparation method to meet the challenges of drugs which are characterized by poor rates of transdermal absorption. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Identifying preferred habitats of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) through patch use.

PubMed

Emerson, Sara E; Brown, Joel S

2013-11-01

To examine habitat preferences of two groups of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) in the Soutpansberg, South Africa, we used experimental food patches in fragments of tall forest and in bordering secondary growth short forest. Additionally, to test for the impacts of group cohesion and movement on habitat use, we tested for the interaction of space and time in our analyses of foraging intensity in the experimental food patches placed throughout the home ranges of the two groups. We expected the monkeys to harvest the most from patches in tall forest habitats and the least from patches in short forest. Further, because the monkeys move through their habitats in groups, we expected to see group cohesion effects illustrated by daily spatial variation in the monkeys’ use of widespread foraging grids. In the forest height experiments, the two groups differed in their foraging responses, with 8% greater foraging overall for one group. However, forest height did not significantly impact foraging in either group, meaning that, given feeding opportunities, samango monkeys are able to utilise secondary growth forest. For one group, missed opportunity costs of staying with the group appeared through the statistical interaction of day with foraging location (the monkeys did not always spread out to take advantage of all available food patches). In several subsequent experiments in widespread grids, significant daily spatial variation in foraging occurred, pointing to spatial cohesion during group movement as likely being an important predictor of habitat use. For an individual social forager, staying with the group may be more important than habitat type in driving habitat selection.

Ultra low concentration deltamethrin loaded patch development and evaluation of its repellency against dengue vector Aedes (S) albopictus

PubMed Central

2013-01-01

Background Mosquito repellents and emanators confer protection against mosquito bites through spatial action of emanated vapours which are released into the adjoining environment. Synthetic insecticides released into the environment in ultra low volume vapour phase deter the mosquitoes from biting humans in a protected space. Methods Formulation patches were prepared using the solvent evaporation method over a backing membrane and using Dibutylphthalate (DBT) as a plasticizer. The effect of formulation variables on the deltamethrin release from the patch matrices were studied under accelerated conditions, whereas, HPLC was used for quantitative estimation of deltamethrin. The prepared patch formulations were subjected to physicochemical studies, such as, deltamethrin content, thickness, weight variation, percent moisture content, moisture uptake, surface area and surface pH determination. Deltamethrin-polymer interaction and compatibility was ascertained using DSC and FT-IR, while surface morphology and deltamethrin distribution in the patch were studied using SEM technique. Repellent activity of the patch formulations was evaluated against Ae. albopictus mosquitoes. Results Blends of polymeric combinations of polyvinylpyrrolidone (PVP) and ethyl-cellulose (EC) with admixture of deltamethrin provided prolonged repellent activity against Ae. albopictus mosquitoes. Physicochemical characterisation indicated the suitability of deltamethrin patch formulation with the polymeric combinations of PVP and EC. Patches were very effective against laboratory reared Ae. albopictus mosquitoes. No significant difference was observed between the performance of test patches and commercially available repellent cream Mosqshield®. Conclusion Deltamethrin loaded patches provided effective repellency against Ae. albopictus mosquitoes. The study emphasised that deltamethrin released to the environment in low concentration could be an excellent spatial repellent against hematophagous mosquitoes. PMID:24289656

Rosacea and contact allergy to cosmetics and topical medicaments--retrospective analysis of multicentre surveillance data 1995-2002.

PubMed

Jappe, U; Schnuch, A; Uter, W

2005-02-01

The role of contact allergy in rosacea has rarely been investigated. In this retrospective study, 361 out of 76,697 patients tested and documented by the Information Network of Departments of Dermatology between 1995 and 2002 had rosacea. Patch tests included standard series and constituents of cosmetics and topical medicaments. 118/361 had additionally been patch tested with their own cosmetics/medicaments. Positive reactions occurred to nickel (II) sulfate in 9.3%, fragrance mix in 8.8%, thimerosal in 6.9%, Myroxylon pereirae resin in 5.9%, potassium dichromate in 4.6% and propolis in 2.8%. Whereas rosacea patients had a significantly higher risk of contact allergy to propolis compared to the remaining patients, in an age- and sex-adjusted analysis, contact allergy to nickel was significantly less frequent in this group. For Lyral, the risk was elevated, albeit not significantly. Only 2/329 patients were positive to neomycin sulfate and 1/100 to gentamicin sulfate, among the panel of (topical) antibiotics tested. Among 118 patients tested with their own products, 3 were tested to metronidazole, 1 reacting positively. Irritant or doubtful patch test reactions were provoked by various substances (vehicles, oxidants and preservatives of various creams), which might also be clinically important, considering the heightened sensitivity of rosaceous skin.

Predator-Prey Interactions Shape Thermal Patch Use in a Newt Larvae-Dragonfly Nymph Model

PubMed Central

Gvoždík, Lumír; Černická, Eva; Van Damme, Raoul

2013-01-01

Thermal quality and predation risk are considered important factors influencing habitat patch use in ectothermic prey. However, how the predator’s food requirement and the prey’s necessity to avoid predation interact with their respective thermoregulatory strategies remains poorly understood. The recently developed ‘thermal game model’ predicts that in the face of imminent predation, prey should divide their time equally among a range of thermal patches. In contrast, predators should concentrate their hunting activities towards warmer patches. In this study, we test these predictions in a laboratory setup and an artificial environment that mimics more natural conditions. In both cases, we scored thermal patch use of newt larvae (prey) and free-ranging dragonfly nymphs (predators). Similar effects were seen in both settings. The newt larvae spent less time in the warm patch if dragonfly nymphs were present. The patch use of the dragonfly nymphs did not change as a function of prey availability, even when the nymphs were starved prior to the experiment. Our behavioral observations partially corroborate predictions of the thermal game model. In line with asymmetric fitness pay-offs in predator-prey interactions (the ‘life-dinner’ principle), the prey’s thermal strategy is more sensitive to the presence of predators than vice versa. PMID:23755175

Do geese fully develop brood patches? A histological analysis of lesser snow geese (Chen caerulescens caerulescens) and Ross's geese (C. rossii)

USGS Publications Warehouse

Jonsson, J.E.; Afton, A.D.; Homberger, D.G.; Henk, W.G.; Alisauskas, R.T.

2006-01-01

Most birds develop brood patches before incubation; epidermis and dermis in the brood patch region thicken, and the dermal connective tissue becomes increasingly vascularized and infiltrated by leukocytes. However, current dogma states that waterfowl incubate without modifications of skin within the brood patch region. The incubation periods of lesser snow geese (Chen caerulescens caerulescens; hereafter called snow geese) and Ross's geese (C. rossii) are 2-6 days shorter than those of other goose species; only females incubate. Thus, we hypothesized that such short incubation periods would require fully developed brood patches for sufficient heat transfer from incubating parents to eggs. We tested this hypothesis by analyzing the skin histology of abdominal regions of snow and Ross's geese collected at Karrak Lake, Nunavut, Canada. For female snow geese, we found that epidermis and dermis had thickened and vascularization of dermis was 14 times greater, on average, than that observed in males (n=5 pairs). Our results for Ross's geese (n=5 pairs) were more variable, wherein only one of five female Ross's geese fully developed a brood patch. Our results are consistent with three hypotheses about brood patch development and its relationship with different energetic cost-benefit relationships, resulting from differences in embryonic development and body size. ?? Springer-Verlag 2006.

Melatonin mediates vasodilation through both direct and indirect activation of BKCa channels.

PubMed

Zhao, T; Zhang, H; Jin, C; Qiu, F; Wu, Y; Shi, L

2017-10-01

Melatonin, synthesized primarily by the pineal gland, is a neuroendocrine hormone with high membrane permeability. The vascular effects of melatonin, including vasoconstriction and vasodilation, have been demonstrated in numerous studies. However, the mechanisms underlying these effects are not fully understood. Large-conductance Ca 2+ -activated K + (BK Ca ) channels are expressed broadly on smooth muscle cells and play an important role in vascular tone regulation. This study explored the mechanisms of myocyte BK Ca channels and endothelial factors underlying the action of melatonin on the mesenteric arteries (MAs). Vascular contractility and patch-clamp studies were performed on myocytes of MAs from Wistar rats. Melatonin induced significant vasodilation on MAs. In the presence of N ω -nitro-l-arginine methyl ester (l-NAME), a potent endothelial oxide synthase (eNOS) inhibitor, melatonin elicited concentration-dependent relaxation, with lowered pIC 50 The effect of melatonin was significantly attenuated in the presence of BK Ca channel blocker iberiotoxin or MT1/MT2 receptor antagonist luzindole in both (+) l-NAME and (-) l-NAME groups. In the (+) l-NAME group, iberiotoxin caused a parallel rightward shift of the melatonin concentration-relaxation curve, with pIC 50 lower than that of luzindole. Both inside-out and cell-attached patch-clamp recordings showed that melatonin significantly increased the open probability, mean open time and voltage sensitivity of BK Ca channels. In a cell-attached patch-clamp configuration, the melatonin-induced enhancement of BK Ca channel activity was significantly suppressed by luzindole. These findings indicate that in addition to the activation of eNOS, melatonin-induced vasorelaxation of MAs is partially attributable to its direct (passing through the cell membrane) and indirect (via MT1/MT2 receptors) activation of the BK Ca channels on mesenteric arterial myocytes. © 2017 Society for Endocrinology.

Temperature responses of carbon monoxide and hydrogen uptake by vegetated and unvegetated volcanic cinders

PubMed Central

King, Caitlin E; King, Gary M

2012-01-01

Ecosystem succession on a large deposit of volcanic cinders emplaced on Kilauea Volcano in 1959 has resulted in a mosaic of closed-canopy forested patches and contiguous unvegetated patches. Unvegetated and unshaded surface cinders (Bare) experience substantial diurnal temperature oscillations ranging from moderate (16 °C) to extreme (55 °C) conditions. The surface material of adjacent vegetated patches (Canopy) experiences much smaller fluctuations (14–25 °C) due to shading. To determine whether surface material from these sites showed adaptations by carbon monoxide (CO) and hydrogen (H2) consumption to changes in ambient temperature regimes accompanying succession, we measured responses of CO and H2 uptake to short-term variations in temperature and long-term incubations at elevated temperature. Based on its broader temperature optimum and lower activation energy, Canopy H2 uptake was less sensitive than Bare H2 uptake to temperature changes. In contrast, Bare and Canopy CO uptake responded similarly to temperature during short-term incubations, indicating no differences in temperature sensitivity. However, during extended incubations at 55 °C, CO uptake increased for Canopy but not Bare material, which indicated that the former was capable of thermal adaptation. H2 uptake for material from both sites was completely inhibited at 55 °C throughout extended incubations. These results indicated that plant development during succession did not elicit differences in short-term temperature responses for Bare and Canopy CO uptake, in spite of previously reported differences in CO oxidizer community composition, and differences in average daily and extreme temperatures. Differences associated with vegetation due to succession did, however, lead to a notable capacity for thermophilic CO uptake by Canopy but not Bare material. PMID:22258097

Temperature responses of carbon monoxide and hydrogen uptake by vegetated and unvegetated volcanic cinders.

PubMed

King, Caitlin E; King, Gary M

2012-08-01

Ecosystem succession on a large deposit of volcanic cinders emplaced on Kilauea Volcano in 1959 has resulted in a mosaic of closed-canopy forested patches and contiguous unvegetated patches. Unvegetated and unshaded surface cinders (Bare) experience substantial diurnal temperature oscillations ranging from moderate (16 °C) to extreme (55 °C) conditions. The surface material of adjacent vegetated patches (Canopy) experiences much smaller fluctuations (14-25 °C) due to shading. To determine whether surface material from these sites showed adaptations by carbon monoxide (CO) and hydrogen (H(2)) consumption to changes in ambient temperature regimes accompanying succession, we measured responses of CO and H(2) uptake to short-term variations in temperature and long-term incubations at elevated temperature. Based on its broader temperature optimum and lower activation energy, Canopy H(2) uptake was less sensitive than Bare H(2) uptake to temperature changes. In contrast, Bare and Canopy CO uptake responded similarly to temperature during short-term incubations, indicating no differences in temperature sensitivity. However, during extended incubations at 55 °C, CO uptake increased for Canopy but not Bare material, which indicated that the former was capable of thermal adaptation. H(2) uptake for material from both sites was completely inhibited at 55 °C throughout extended incubations. These results indicated that plant development during succession did not elicit differences in short-term temperature responses for Bare and Canopy CO uptake, in spite of previously reported differences in CO oxidizer community composition, and differences in average daily and extreme temperatures. Differences associated with vegetation due to succession did, however, lead to a notable capacity for thermophilic CO uptake by Canopy but not Bare material.

Variations in laser energy outputs over a series of simulated treatments.

PubMed

Lister, T S; Brewin, M P

2014-10-01

Test patches are routinely employed to determine the likely efficacy and the risk of adverse effects from cutaneous laser treatments. However, the degree to which these represent a full treatment has not been investigated in detail. This study aimed to determine the variability in pulse-to-pulse output energy from a representative selection of cutaneous laser systems in order to assess the value of laser test patches. The output energies of each pulse from seven cutaneous laser systems were measured using a pyroelectric measurement head over a 2-h period, employing a regime of 10-min simulated treatments followed by a 5-min rest period (between patients). Each laser system appeared to demonstrate a different pattern of variation in output energy per pulse over the period measured. The output energies from a range of cutaneous laser systems have been shown to vary considerably between a representative test patch and a full treatment, and over the course of an entire simulated clinic list. © 2014 British Association of Dermatologists.

Experimental Spin Testing of Integrally Damped Composite Plates

NASA Technical Reports Server (NTRS)

Kosmatka, John

1998-01-01

The experimental behavior of spinning laminated composite pretwisted plates (turbo-fan blade-like) with small (less than 10% by volume) integral viscoelastic damping patches was investigated at NASA-Lewis Research Center. Ten different plate sets were experimentally spin tested and the resulting data was analyzed. The first-four plate sets investigated tailoring patch locations and definitions to damp specific modes on spinning flat graphite/epoxy plates as a function of rotational speed. The remaining six plate sets investigated damping patch size and location on specific modes of pretwisted (30 degrees) graphite/epoxy plates. The results reveal that: (1) significant amount of damping can be added using a small amount of damping material, (2) the damped plates experienced no failures up to the tested 28,000 g's and 750,000 cycles, (3) centrifugal loads caused an increase in bending frequencies and corresponding reductions in bending damping levels that are proportional to the bending stiffness increase, and (4) the centrifugal loads caused a decrease in torsion natural frequency and increase in damping levels of pretwisted composite plates.

Impulse Testing of Corporate-Fed Patch Array Antennas

NASA Technical Reports Server (NTRS)

Chamberlain, Neil F.

2011-01-01

This paper discusses a novel method for detecting faults in antenna arrays. The method, termed Impulse Testing, was developed for corporate-fed patch arrays where the element is fed by a probe and is shorted at its center. Impulse Testing was devised to supplement conventional microwave measurements in order to quickly verify antenna integrity. The technique relies on exciting each antenna element in turn with a fast pulse (or impulse) that propagates through the feed network to the output port of the antenna. The resulting impulse response is characteristic of the path through the feed network. Using an oscilloscope, a simple amplitude measurement can be made to detect faults. A circuit model of the antenna elements and feed network was constructed to assess various fault scenarios and determine fault-detection thresholds. The experimental setup and impulse measurements for two patch array antennas are presented. Advantages and limitations of the technique are discussed along with applications to other antenna array topologies

[Occupational contact dermatitis in metal workers and gender effect].

PubMed

Filon, F Larese; Marzioti, G; Fortina, A Belloni; Peserico, A; De Toni, A; Corradini, M T; Carrabba, E; Fiorito, A

2007-01-01

Contact dermatitis is more frequent among women for anatomical reasons and for extraprofessional exposure to irritants and detergents during homeworks. In addition sensitisation to contact haptens is different in sexes. The aim of our work was to evaluate the association between patch test skin sensitizations and professional exposure to metals analyzing data for gender. Of the 15.217 patients patch tested for dermatitis, 678 were metalworkers. The statistical analysis revealed a significant association between dermatitis and sensitisation to nickel in professional exposed women (OR = 1.68; LC50% 1.11-6.50) while metal sensitisation (Cr.Ni and Co) was not relevant in men: for them a significant association between dermatitis and sensitisation was found to quaternium (OR = 3.91; LC95% 1.18-12.9), to mercaptobenzothiazole (OR = 2.69; LC50% 1.11-6.50) and to ethylendiamine dichloride (OR = 2.53; LC95% 1-6.41). The authors stress the need to evaluate patch test sensitisation considering gender effects.

Patch testing with the European baseline series fragrance markers: a 2016 update.

PubMed

Ung, C Y; White, J M L; White, I R; Banerjee, P; McFadden, J P

2018-03-01

Fragrance contact allergy is common and is currently screened for using the following European baseline series fragrance markers: fragrance mix (FM)I, FMII, Myroxylon pereirae and hydroxyisohexyl 3-cyclohexene carboxaldehyde. To investigate the validity of patch testing using these fragrance markers in detecting fragrance allergy to 26 individual fragrance substances for which cosmetic ingredient labelling is mandatory within the European Union. We conducted a retrospective review of the patch test records of all patients with eczema who underwent testing using the European baseline series, extended with the individual fragrance substances during the period from 2015 to 2016. Overall, 359 patients (17·2%) reacted to one or more allergens from the labelled fragrance substance series and/or a fragrance marker from the European baseline series. The allergens that were positive with the greatest frequencies were oxidized linalool [n = 154; 7·4%, 95% confidence interval (CI) 6·3-8·6], oxidized limonene (n = 89; 4·3%, 95% CI 3·4-5·2) and Evernia furfuracea (n = 44; 2·1%, 95% CI 1·5-2·8). Of the 319 patients who reacted to any of the labelled fragrance substances, only 130 (40·8%) also reacted to a baseline series fragrance marker. The sensitivity of our history-taking for detecting fragrance allergy was 25·7%. Given the evolving trends in fragrance allergy, patch testing with FMI, FMII, M. pereirae and hydroxyisohexyl 3-cyclohexene carboxaldehyde is no longer sufficient for screening for fragrance allergy. © 2017 British Association of Dermatologists.

An ATP-gated cation channel with some P2Z-like characteristics in gastric smooth muscle cells of toad.

PubMed Central

Ugur, M; Drummond, R M; Zou, H; Sheng, P; Singer, J J; Walsh, J V

1997-01-01

1. Whole-cell and single-channel currents elicited by extracellular ATP were studied in freshly dissociated smooth muscle cells from the stomach of the toad Bufo marinus using standard patch clamp and microfluorimetric techniques. 2. This ATP-gated cation channel shares a number of pharmacological and functional properties with native rat myometrium receptors, certain native P2Z purinoceptors and the recently cloned P2X7 purinoceptor. But, unlike the last two, the ATP-gated channel does not mediate the formation of large non-specific pores. Thus, it may represent a novel member of the P2X or P2Z class. 3. Extracellular application of ATP (> or = 150 microM) elicited an inward whole-cell current at negative holding potentials that was inwardly rectifying and showed no sign of desensitization. Na+, Cs+ and, to a lesser degree, the organic cation choline served as charge carriers, but Cl- did not. Ratiometric fura-2 measurements indicated that the current is carried in part by Ca2+. The EC50 for ATP was 700 microM in solutions with a low divalent cation concentration. 4. ATP (> or = 100 microM) at the extracellular surface of cell-attached or excised patches elicited inwardly rectifying single-channel currents with a 22 pS conductance. Cl- did not serve as a charge carrier but both Na+ and Cs+ did, as did choline to a lesser extent. The mean open time of the channel was quite long, with a range in hundreds of milliseconds at a holding potential of -70 mV. 5. Mg2+ and Ca2+ decreased the magnitude of the ATP-induced whole-cell currents. Mg2+ decreased both the amplitude and the activity of ATP-activated single-channel currents. 6. ADP, UTP, P1, P5-di-adenosine pentaphosphate (AP5A), adenosine and alpha, beta-methylene ATP (alpha, beta-Me-ATP) did not induce significant whole-cell current. ATP-gamma-S and 2-methylthio ATP (2-Me-S-ATP) were significantly less effective than ATP in inducing whole-cell currents, whereas benzoylbenzoyl ATP (BzATP) was more effective. BzATP, alpha, beta-Me-ATP, ATP-gamma-S and 2-Me-S-ATP induced single-channel currents, but a higher concentration of alpha, beta-Me-ATP was required. 7. BzATP did not induce the formation of large non-specific pores, as assayed using mag-fura-2 as a high molecular mass probe. PMID:9032690

Relationships of habitat patch size to predator community and survival of duck nests

USGS Publications Warehouse

Sovada, M.A.; Zicus, M.C.; Greenwood, R.J.; Rave, D.P.; Newton, W.E.; Woodward, R.O.; Beiser, J.A.

2000-01-01

We studied duck nest success and predator community composition in relation to size of discrete patches of nesting cover in the Prairie Pothole Region (PPR) of the United States in 1993-95. We focused on nests in uplands that were seeded to perennial grasses and forbs and enrolled in the Conservation Reserve Program (CRP) in Minnesota, North Dakota, and South Dakota. We estimated daily survival rates (DSRs) of upland duck nests and indices of activity for red foxes (Vulpes vulpes), coyotes (Canis latrans), American badgers (Taxidea taxus), striped skunks (Mephitis mephitis), and Franklin's ground squirrels (Spermophilus franklinii), and related these variables to habitat patch size. The effect of patch size (small vs. large) on estimated annual mean DSR was dependent on date of nest initiation (early vs. late) and year. Examination of within-year comparisons for early and late nests suggested that DSR was generally greater in larger habitat patches. Activity indices for the 5 mammalian nest predators were influenced differently by year, location, and patch size. Activity indices of the red fox were greatest in small patches. Coyote indices were the most inconsistent, demonstrating a year X location X patch size interaction. Activity indices of the striped skunk and American badger varied only among years. Franklin's ground squirrel indices were affected by study area location, with higher indices in the southeast than the northwest. Red fox activity was weakly correlated with that of the striped skunk and coyote. Although a positive relationship between habitat patch size and nest success probably exists, we believe the experiment to fully test this hypothesis will continue to be elusive.

The study of microstrip antenna arrays and related problems

NASA Technical Reports Server (NTRS)

Lo, Y. T.

1986-01-01

In February, an initial computer program to be used in analyzing the four-element array module was completed. This program performs the analysis of modules composed of four rectangular patches which are corporately fed by a microstrip line network terminated in four identical load impedances. Currently, a rigorous full-wave analysis of various types of microstrip line feed structures and patches is being performed. These tests include the microstrip line feed between layers of different electrical parameters. A method of moments was implemented for the case of a single dielectric layer and microstrip line fed rectangular patches in which the primary source is assumed to be a magnetic current ribbon across the line some distance from the patch. Measured values are compared with those computed by the program.

Nickel and cobalt release from children's toys purchased in Denmark and the United States.

PubMed

Jensen, Peter; Hamann, Dathan; Hamann, Carsten R; Jellesen, Morten S; Jacob, Sharon E; Thyssen, Jacob P

2014-01-01

Nickel is the most common allergen detected by patch testing in children. There is an increasing number of cases in children who have not had exposure to piercing. Although the clinical relevance of nickel patch test reactions in children is sometimes uncertain, continued vigilance to identify new sources of nickel exposure in this age group is important. Recent case reports have described allergic nickel contact dermatitis in children following exposure to toys, but the magnitude of this problem is unknown. The aim of this study was to evaluate nickel and cobalt release from children's toys. We purchased 212 toys in 18 different retail and online stores in the United States and Denmark. Nickel and cobalt release was tested using the dimethylglyoxime and cobalt screening spot tests. A total of 73 toys (34.4%) released nickel, and none released cobalt. Toys are a commonly overlooked source of nickel exposure and sensitization. Therefore, dermatologists, allergists, and pediatricians should consider the role of toys in their evaluation of children with dermatitis, and the parents of children with positive nickel patch test reactions should be told that toys may release nickel and be a potential chemical source in the manifestation of allergic contact dermatitis.

Temporal trends of preservative allergy in Denmark (1985-2008).

PubMed

Thyssen, Jacob P; Engkilde, Kåre; Lundov, Michael D; Carlsen, Berit C; Menné, Torkil; Johansen, Jeanne D

2010-02-01

Most cosmetics and industrial products contain preservatives. Preservative allergy is common and, historically, changing contact allergy epidemics caused by preservatives have been observed. In 1997, Alan Dillarstone predicted a stable development of preservative allergy following mandatory ingredient labelling on cosmetic products. To investigate the development in the prevalence of preservative allergy in Denmark over a 24-year period (1985-2008) and to challenge the prediction made by Dillarstone. A retrospective analysis of patch test data was performed (n = 18179). Comparisons were made using a chi(2) test. Logistic regression analyses were used to test for associations. The development of preservative allergy mirrored those of other European patch test centres. The development was not dependent on sex or age group. The prevalence was higher among women and those aged 41-60 years. Formaldehyde allergy was persistently prevalent over the study years. The overall prevalence of preservative allergy increased significantly (P(trend) = 0.001), mainly because of patch testing with additional preservatives in recent years. Dillarstone's prediction was confirmed as the prevalence of contact allergy to individual preservatives remained relatively stable. However, the overall burden of preservative allergy seemed to increase. Introduction of new preservatives may add to the burden of contact allergy.

Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam.

PubMed

Kieć-Świerczyńska, Marta; Swierczyńska-Machura, Dominika; Chomiczewska-Skóra, Dorota; Nowakowska-Świrta, Ewa; Kręcisz, Beata

2014-04-01

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4'-diphenylmethane diisocyanate (MDI). From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent. Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers. In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.

Multicentre study of allergic contact cheilitis from toothpastes.

PubMed

Francalanci, S; Sertoli, A; Giorgini, S; Pigatto, P; Santucci, B; Valsecchi, R

2000-10-01

The present work reports the results of a multicentre study of toothpaste allergic contact cheilitis (TACC) conducted by GIRDCA (Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali). The study examined 54 patients with eczematous lesions on the lips, the possible cause of which was suspected to be the use of toothpastes. Patch tests were conducted with a standard series, a specially-targeted series (toothpaste cheilitis series, TCS), and with suspected toothpaste(s). A stop-restart test (SRT) was carried out with these, together with a use test to identify possible alternative products. The TCS produced 17 positive reactions in 13 patients, the most frequent being to spearmint oil. Of the 54 patients, 5 displayed positive reactions only to the TCS. The patch tests with toothpaste produced positive reactions in 11/32 patients, the SRT a positive response in 10/12 cases. The diagnosis of TACC was confirmed in 15/54 patients. Alternative products were identified for 5 patients. In conclusion, the allergens most frequently responsible for TACC were the flavourings, and the additional series proved to be useful in many cases (together with patch tests with toothpastes and the SRT) for correct diagnosis and to initiate effective prevention.

Fragrance allergy in patients with hand eczema - a clinical study.

PubMed

Heydorn, Siri; Johansen, Jeanne Duus; Andersen, Klaus E; Bruze, Magnus; Svedman, Cecilia; White, Ian R; Basketter, David A; Menné, Torkil

2003-06-01

Fragrance allergy and hand eczema are both common among dermatological patients. Fragrance mix (FM) and its constituents have a recognized relevance to exposure to fine fragrances and cosmetic products. Based on extensive chemical analysis and database search, a new selection of fragrances was established, including 14 known fragrance allergens present in products to which hand exposure would occur. A non-irritating patch-test concentration for some fragrances was established in 212 consecutive patients. 658 consecutive patients presenting with hand eczema were patch tested with the European standard series and the developed selection of fragrances. 67 (10.2%) of the 658 patients had a positive reaction to 1 or more of our selection of fragrance chemicals present in the new selection. The most common reactions to fragrances not included in the FM were to citral, Lyral (hydroxyisohexyl-3-cyclohexene carboxaldehyde) and oxidized l-limonene. A concomitant reaction to the FM identified potential fragrance allergy in less than (1/2) of these patients. Exposure assessment and a statistically significant association between a positive patch test to our selected fragrances and patients' history support the relevance of this selection of fragrances. Those with a positive reaction to our selected fragrances were significantly more likely to have 1 or more positive patch tests in the standard series. This observation is the basis for the hypothesis concerning cross-reactivity and the effect of simultaneous exposure. The study found that fragrance allergy could be a common problem in patients with eczema on the hands.

In Vivo Evaluation of Wearable Head Impact Sensors.

PubMed

Wu, Lyndia C; Nangia, Vaibhav; Bui, Kevin; Hammoor, Bradley; Kurt, Mehmet; Hernandez, Fidel; Kuo, Calvin; Camarillo, David B

2016-04-01

Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for α(mag)) and the skull cap (320% NRMS error for a(mag), 500% for α(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.

Planar patch clamp: advances in electrophysiology.

PubMed

Brüggemann, Andrea; Farre, Cecilia; Haarmann, Claudia; Haythornthwaite, Ali; Kreir, Mohamed; Stoelzle, Sonja; George, Michael; Fertig, Niels

2008-01-01

Ion channels have gained increased interest as therapeutic targets over recent years, since a growing number of human and animal diseases have been attributed to defects in ion channel function. Potassium channels are the largest and most diverse family of ion channels. Pharmaceutical agents such as Glibenclamide, an inhibitor of K(ATP) channel activity which promotes insulin release, have been successfully sold on the market for many years. So far, only a small group of the known ion channels have been addressed as potential drug targets. The functional testing of drugs on these ion channels has always been the bottleneck in the development of these types of pharmaceutical compounds.New generations of automated patch clamp screening platforms allow a higher throughput for drug testing and widen this bottleneck. Due to their planar chip design not only is a higher throughput achieved, but new applications have also become possible. One of the advantages of planar patch clamp is the possibility of perfusing the intracellular side of the membrane during a patch clamp experiment in the whole-cell configuration. Furthermore, the extracellular membrane remains accessible for compound application during the experiment.Internal perfusion can be used not only for patch clamp experiments with cell membranes, but also for those with artificial lipid bilayers. In this chapter we describe how internal perfusion can be applied to potassium channels expressed in Jurkat cells, and to Gramicidin channels reconstituted in a lipid bilayer.

Infrared moving small target detection based on saliency extraction and image sparse representation

NASA Astrophysics Data System (ADS)

Zhang, Xiaomin; Ren, Kan; Gao, Jin; Li, Chaowei; Gu, Guohua; Wan, Minjie

2016-10-01

Moving small target detection in infrared image is a crucial technique of infrared search and tracking system. This paper present a novel small target detection technique based on frequency-domain saliency extraction and image sparse representation. First, we exploit the features of Fourier spectrum image and magnitude spectrum of Fourier transform to make a rough extract of saliency regions and use a threshold segmentation system to classify the regions which look salient from the background, which gives us a binary image as result. Second, a new patch-image model and over-complete dictionary were introduced to the detection system, then the infrared small target detection was converted into a problem solving and optimization process of patch-image information reconstruction based on sparse representation. More specifically, the test image and binary image can be decomposed into some image patches follow certain rules. We select the target potential area according to the binary patch-image which contains salient region information, then exploit the over-complete infrared small target dictionary to reconstruct the test image blocks which may contain targets. The coefficients of target image patch satisfy sparse features. Finally, for image sequence, Euclidean distance was used to reduce false alarm ratio and increase the detection accuracy of moving small targets in infrared images due to the target position correlation between frames.

Contact allergy to essential oils: current patch test results (2000-2008) from the Information Network of Departments of Dermatology (IVDK).

PubMed

Uter, Wolfgang; Schmidt, Erich; Geier, Johannes; Lessmann, Holger; Schnuch, Axel; Frosch, Peter

2010-11-01

Essential oils are used in perfumery and in products for aromatherapy or balneotherapy. Previous studies have shown some to be important contact sensitizers. A practical diagnostic approach, based on the results of a large, central European network and other evidence, is needed. Data of the Information Network of Departments of Dermatology (IVDK; www.ivdk.org) on all patients patch tested between January 2000 and December 2008 with essential oils were retrospectively analysed. 15 682 patients of 84 716 consulting in the period had been tested with at least one essential oil, and 637 reacted positively to at least one of the essential oils, most commonly to ylang-ylang oil (I and II) (3.1% as weighted mean of positive tests in special series and consecutive testing), lemongrass oil (1.8%), jasmine absolute (1.6%), sandalwood oil and clove oil (1.5% each). Cross-reactivity between distillate and main allergen, if available, was marked. Patch testing the important essential oils should be considered in patients with a suggestive history. Additionally, culprit products brought in by the patient should be tested, closing a diagnostic gap by (i) including those other essential oils not included in the commercial test series and (ii) providing a means of testing with the oxidized substances to which the patient had actually been exposed. © 2010 John Wiley & Sons A/S.

Analyzing Milestones in Smoking Cessation: Illustration in a Nicotine Patch Trial in Adult Smokers

ERIC Educational Resources Information Center

Shiffman, Saul; Scharf, Deborah M.; Shadel, William G.; Gwaltney, Chad J.; Dang, Qianyu; Paton, Stephanie M.; Clark, Duncan B.

2006-01-01

Tests of addiction treatments seldom reveal where treatment exercises its effect (i.e., promoting initial abstinence, preventing lapses, and/or impeding progression from lapse to relapse). The authors illustrate analyses distinguishing effects on these milestones in a randomized trial of high-dose nicotine patch (35 mg; n = 188) versus placebo (n…

Unusual fentanyl patch administration.

PubMed

Thomas, Sandra; Winecker, Ruth; Pestaner, Joseph P

2008-06-01

Fentanyl is an extremely potent narcotic analgesic that is becoming more popular as a drug of abuse. Because of the unique way in which the drug is packaged and delivered, the potential for unusual methods of abuse exists. We report the first case of true fentanyl patch ingestion in the medical literature. Initially, though unusual, cases of fentanyl ingestion were thought to have been reported, but further investigation of the literature revealed that in other case reports the patches had been held in the mouth and chewed. Because no reports of swallowing the patch had been published, suicide was initially a strong consideration in this case; however, further investigation showed that the decedent and his brother enjoyed swallowing the patches for quick "highs." Cases such as these serve to remind medical examiners and law enforcement officials of the value of performing thorough death investigations by performing complete autopsies with toxicological testing and correlating with investigation information to form an opinion with regard to the cause and manner of death.

The Effects of Platelet-Rich Plasma on Bone Marrow Stromal Cell Transplants for Tendon Healing In Vitro

PubMed Central

Morizaki, Yutaka; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C.

2010-01-01

Purpose In this study we investigated the effect of platelet-rich plasma (PRP) and bone-marrow derived stromal cell (BMSC)-seeded interposition in an in vitro canine tendon repair model. Methods Bone marrow, peripheral blood, and tendons were harvested from mixed breed dogs. BMSC were cultured and passaged from adherent cells of bone marrow suspension. PRP was purified from peripheral blood using a commercial kit. 192 flexor digitorum profundus tendons were used for the study. Tendons repaired with a simple suture were used as a control group. In treatment groups, a collagen gel patch was interposed at the tendon repair site prior to suture. There were three treatment groups according to the type of collagen patch; a patch with PRP, a patch with BMSC, and a patch with PRP and BMSC. The repaired tendons were evaluated by biomechanical testing and by histological survey after 2 and 4 weeks in tissue culture. To evaluate viability, cells were labeled with PKH26 and surveyed under confocal microscopy after culture. Results The maximum breaking strength and stiffness of the healing tendons with the BMSC-seeded PRP patch was significantly higher than the healing tendons without a patch or with a cell-seeded patch (p<0.02). Viable BMSC were present at both 2 and 4 weeks. Conclusions PRP enhanced the effect of BMSC-seeded collagen gel interposition in this in vitro model. Based on these results we now plan to investigate this effect in vivo. PMID:20951509

The predatory mite Phytoseiulus persimilis adjusts patch-leaving to own and progeny prey needs.

PubMed

Vanas, V; Enigl, M; Walzer, A; Schausberger, P

2006-01-01

Integration of optimal foraging and optimal oviposition theories suggests that predator females should adjust patch leaving to own and progeny prey needs to maximize current and future reproductive success. We tested this hypothesis in the predatory mite Phytoseiulus persimilis and its patchily distributed prey, the two-spotted spider mite Tetranychus urticae. In three separate experiments we assessed (1) the minimum number of prey needed to complete juvenile development, (2) the minimum number of prey needed to produce an egg, and (3) the ratio between eggs laid and spider mites left when a gravid P. persimilis female leaves a patch. Experiments (1) and (2) were the pre-requirements to assess the fitness costs associated with staying or leaving a prey patch. Immature P. persimilis needed at least 7 and on average 14+/-3.6 (SD) T. urticae eggs to reach adulthood. Gravid females needed at least 5 and on average 8.5+/-3.1 (SD) T. urticae eggs to produce an egg. Most females left the initial patch before spider mite extinction, leaving prey for progeny to develop to adulthood. Females placed in a low density patch left 5.6+/-6.1 (SD) eggs per egg laid, whereas those placed in a high density patch left 15.8+/-13.7 (SD) eggs per egg laid. The three experiments in concert suggest that gravid P. persimilis females are able to balance the trade off between optimal foraging and optimal oviposition and adjust patch-leaving to own and progeny prey needs.

Eliciting expert opinion for economic models: an applied example.

PubMed

Leal, José; Wordsworth, Sarah; Legood, Rosa; Blair, Edward

2007-01-01

Expert opinion is considered as a legitimate source of information for decision-analytic modeling where required data are unavailable. Our objective was to develop a practical computer-based tool for eliciting expert opinion about the shape of the uncertainty distribution around individual model parameters. We first developed a prepilot survey with departmental colleagues to test a number of alternative approaches to eliciting opinions on the shape of the uncertainty distribution around individual parameters. This information was used to develop a survey instrument for an applied clinical example. This involved eliciting opinions from experts to inform a number of parameters involving Bernoulli processes in an economic model evaluating DNA testing for families with a genetic disease, hypertrophic cardiomyopathy. The experts were cardiologists, clinical geneticists, and laboratory scientists working with cardiomyopathy patient populations and DNA testing. Our initial prepilot work suggested that the more complex elicitation techniques advocated in the literature were difficult to use in practice. In contrast, our approach achieved a reasonable response rate (50%), provided logical answers, and was generally rated as easy to use by respondents. The computer software user interface permitted graphical feedback throughout the elicitation process. The distributions obtained were incorporated into the model, enabling the use of probabilistic sensitivity analysis. There is clearly a gap in the literature between theoretical elicitation techniques and tools that can be used in applied decision-analytic models. The results of this methodological study are potentially valuable for other decision analysts deriving expert opinion.

Comparative Analysis of the Biaxial Mechanical Behavior of Carotid Wall Tissue and Biological and Synthetic Materials Used for Carotid Patch Angioplasty

PubMed Central

Kamenskiy, Alexey V.; Pipinos, Iraklis I.; MacTaggart, Jason N.; Jaffar Kazmi, Syed A.; Dzenis, Yuris A.

2011-01-01

Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of patching materials are available for use while new materials are being continuously developed. Surprisingly little is known about the mechanical properties of these materials and how these properties compare with those of the carotid artery wall. Mismatch of the mechanical properties can produce mechanical and hemodynamic effects that may compromise the long-term patency of the endarterectomized arterial segment. The aim of this paper was to systematically evaluate and compare the biaxial mechanical behavior of the most commonly used patching materials. We compared PTFE (n = 1), Dacron (n = 2), bovine pericardium (n = 10), autogenous greater saphenous vein (n = 10), and autogenous external jugular vein (n = 9) with the wall of the common carotid artery (n = 18). All patching materials were found to be significantly stiffer than the carotid wall in both the longitudinal and circumferential directions. Synthetic patches demonstrated the most mismatch in stiffness values and vein patches the least mismatch in stiffness values compared to those of the native carotid artery. All biological materials, including the carotid artery, demonstrated substantial nonlinearity, anisotropy, and variability; however, the behavior of biological and biologically-derived patches was both qualitatively and quantitatively different from the behavior of the carotid wall. The majority of carotid arteries tested were stiffer in the circumferential direction, while the opposite anisotropy was observed for all types of vein patches and bovine pericardium. The rates of increase in the nonlinear stiffness over the physiological stress range were also different for the carotid and patching materials. Several carotid wall samples exhibited reverse anisotropy compared to the average behavior of the carotid tissue. A similar characteristic was observed for two of 19 vein patches. The obtained results quantify, for the first time, significant mechanical dissimilarity of the currently available patching materials and the carotid artery. The results can be used as guidance for designing more efficient patches with mechanical properties resembling those of the carotid wall. The presented systematic comparative mechanical analysis of the existing patching materials provides valuable information for patch selection in the daily practice of carotid surgery and can be used in future clinical studies comparing the efficacy of different patches in the performance of carotid endarterectomy. PMID:22168740

Association between cobalt allergy and dermatitis caused by leather articles--a questionnaire study.

PubMed

Bregnbak, David; Thyssen, Jacob P; Zachariae, Claus; Menné, Torkil; Johansen, Jeanne D

2015-02-01

Cobalt is a strong skin sensitizer and a prevalent contact allergen. Recent studies have recognized exposure to leather articles as a potential cause of cobalt allergy. To examine the association between contact allergy to cobalt and a history of dermatitis resulting from exposure to leather. A questionnaire case-control study was performed: the case group consisted of 183 dermatitis patients with a positive patch test reaction to cobalt chloride and a negative patch test reaction to potassium dichromate; the control group consisted of 621 dermatitis patients who did not react to either cobalt or chromium in patch testing. Comparisons were made by use of a χ(2) -test, Fisher's exact, and the Mann-Whitney test. Logistic regression analyses were used to test for associations while taking confounding factors into consideration. Leather was observed as the most frequent exposure source causing dermatitis in the case group. Although the case group significantly more often reported non-occupational dermatitis caused by leather exposure (p < 0.001), no association was found between cobalt allergy and dermatitis caused by work-related exposure to leather. Our study suggests a positive association between cobalt allergy and a history of dermatitis caused by non-occupational exposure to leather articles. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Vehicle classification in WAMI imagery using deep network

NASA Astrophysics Data System (ADS)

Yi, Meng; Yang, Fan; Blasch, Erik; Sheaff, Carolyn; Liu, Kui; Chen, Genshe; Ling, Haibin

2016-05-01

Humans have always had a keen interest in understanding activities and the surrounding environment for mobility, communication, and survival. Thanks to recent progress in photography and breakthroughs in aviation, we are now able to capture tens of megapixels of ground imagery, namely Wide Area Motion Imagery (WAMI), at multiple frames per second from unmanned aerial vehicles (UAVs). WAMI serves as a great source for many applications, including security, urban planning and route planning. These applications require fast and accurate image understanding which is time consuming for humans, due to the large data volume and city-scale area coverage. Therefore, automatic processing and understanding of WAMI imagery has been gaining attention in both industry and the research community. This paper focuses on an essential step in WAMI imagery analysis, namely vehicle classification. That is, deciding whether a certain image patch contains a vehicle or not. We collect a set of positive and negative sample image patches, for training and testing the detector. Positive samples are 64 × 64 image patches centered on annotated vehicles. We generate two sets of negative images. The first set is generated from positive images with some location shift. The second set of negative patches is generated from randomly sampled patches. We also discard those patches if a vehicle accidentally locates at the center. Both positive and negative samples are randomly divided into 9000 training images and 3000 testing images. We propose to train a deep convolution network for classifying these patches. The classifier is based on a pre-trained AlexNet Model in the Caffe library, with an adapted loss function for vehicle classification. The performance of our classifier is compared to several traditional image classifier methods using Support Vector Machine (SVM) and Histogram of Oriented Gradient (HOG) features. While the SVM+HOG method achieves an accuracy of 91.2%, the accuracy of our deep network-based classifier reaches 97.9%.

A specialized face-processing model inspired by the organization of monkey face patches explains several face-specific phenomena observed in humans.

PubMed

Farzmahdi, Amirhossein; Rajaei, Karim; Ghodrati, Masoud; Ebrahimpour, Reza; Khaligh-Razavi, Seyed-Mahdi

2016-04-26

Converging reports indicate that face images are processed through specialized neural networks in the brain -i.e. face patches in monkeys and the fusiform face area (FFA) in humans. These studies were designed to find out how faces are processed in visual system compared to other objects. Yet, the underlying mechanism of face processing is not completely revealed. Here, we show that a hierarchical computational model, inspired by electrophysiological evidence on face processing in primates, is able to generate representational properties similar to those observed in monkey face patches (posterior, middle and anterior patches). Since the most important goal of sensory neuroscience is linking the neural responses with behavioral outputs, we test whether the proposed model, which is designed to account for neural responses in monkey face patches, is also able to predict well-documented behavioral face phenomena observed in humans. We show that the proposed model satisfies several cognitive face effects such as: composite face effect and the idea of canonical face views. Our model provides insights about the underlying computations that transfer visual information from posterior to anterior face patches.

A specialized face-processing model inspired by the organization of monkey face patches explains several face-specific phenomena observed in humans

PubMed Central

Farzmahdi, Amirhossein; Rajaei, Karim; Ghodrati, Masoud; Ebrahimpour, Reza; Khaligh-Razavi, Seyed-Mahdi

2016-01-01

Converging reports indicate that face images are processed through specialized neural networks in the brain –i.e. face patches in monkeys and the fusiform face area (FFA) in humans. These studies were designed to find out how faces are processed in visual system compared to other objects. Yet, the underlying mechanism of face processing is not completely revealed. Here, we show that a hierarchical computational model, inspired by electrophysiological evidence on face processing in primates, is able to generate representational properties similar to those observed in monkey face patches (posterior, middle and anterior patches). Since the most important goal of sensory neuroscience is linking the neural responses with behavioral outputs, we test whether the proposed model, which is designed to account for neural responses in monkey face patches, is also able to predict well-documented behavioral face phenomena observed in humans. We show that the proposed model satisfies several cognitive face effects such as: composite face effect and the idea of canonical face views. Our model provides insights about the underlying computations that transfer visual information from posterior to anterior face patches. PMID:27113635

Habitat fragmentation, vole population fluctuations, and the ROMPA hypothesis: An experimental test using model landscapes.

PubMed

Batzli, George O

2016-11-01

Increased habitat fragmentation leads to smaller size of habitat patches and to greater distance between patches. The ROMPA hypothesis (ratio of optimal to marginal patch area) uniquely links vole population fluctuations to the composition of the landscape. It states that as ROMPA decreases (fragmentation increases), vole population fluctuations will increase (including the tendency to display multi-annual cycles in abundance) because decreased proportions of optimal habitat result in greater population declines and longer recovery time after a harsh season. To date, only comparative observations in the field have supported the hypothesis. This paper reports the results of the first experimental test. I used prairie voles, Microtus ochrogaster, and mowed grassland to create model landscapes with 3 levels of ROMPA (high with 25% mowed, medium with 50% mowed and low with 75% mowed). As ROMPA decreased, distances between patches of favorable habitat (high cover) increased owing to a greater proportion of unfavorable (mowed) habitat. Results from the first year with intensive live trapping indicated that the preconditions for operation of the hypothesis existed (inversely density dependent emigration and, as ROMPA decreased, increased per capita mortality and decreased per capita movement between optimal patches). Nevertheless, contrary to the prediction of the hypothesis that populations in landscapes with high ROMPA should have the lowest variability, 5 years of trapping indicated that variability was lowest with medium ROMPA. The design of field experiments may never be perfect, but these results indicate that the ROMPA hypothesis needs further rigorous testing. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Quantitative detection of glucose level based on radiofrequency patch biosensor combined with volume-fixed structures.

PubMed

Qiang, Tian; Wang, Cong; Kim, Nam-Young

2017-12-15

A concept for characterizing a radiofrequency (RF) patch biosensor combined with volume-fixed structures is presented for timely monitoring of an individual's glucose levels based on frequency variation. Two types of patch biosensors-separately integrated with a backside slot (0.53μL) and a front-side tank (0.70μL) structure-were developed to achieve precise and efficient detection while excluding the effects of interference due to the liquidity, shape, and thickness of the tested glucose sample. A glucose test analyte at different concentrations (50-600mg/dL) was dropped into the volume-fixed structures. It fully interacted with the RF patch electromagnetic field, effectively and sensitively changing the resonance frequency and magnitude of the reflection coefficient. Measurement results based on the resonance frequency showed high sensitivity up to 1.13MHz and 1.97MHz per mg/dL, and low detection limits of 26.54mg/dL and 15.22mg/dL, for the two types of patch biosensors, respectively, as well as a short response time of less than 1s. Excellent reusability of the proposed biosensors was verified through three sets of measurements for each individual glucose sample. Regression analysis revealed a good linear correlation between glucose concentrations and the resonance frequency shift. Moreover, to facilitate a multi-parameter-sensitive detection of glucose, the magnitude of the reflection coefficient was also tested, and it showed a good linear correlation with the glucose concentration. Thus, the proposed approach can be adopted for distinguishing glucose solution levels, and it is a potential candidate for early-stage detection of glucose levels in diabetes patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Very high resolution Earth Observation features for testing the direct and indirect effects of landscape structure on local habitat quality

NASA Astrophysics Data System (ADS)

Mairota, Paola; Cafarelli, Barbara; Labadessa, Rocco; Lovergine, Francesco P.; Tarantino, Cristina; Nagendra, Harini; Didham, Raphael K.

2015-02-01

Modelling the empirical relationships between habitat quality and species distribution patterns is the first step to understanding human impacts on biodiversity. It is important to build on this understanding to develop a broader conceptual appreciation of the influence of surrounding landscape structure on local habitat quality, across multiple spatial scales. Traditional models which report that 'habitat amount' in the landscape is sufficient to explain patterns of biodiversity, irrespective of habitat configuration or spatial variation in habitat quality at edges, implicitly treat each unit of habitat as interchangeable and ignore the high degree of interdependence between spatial components of land-use change. Here, we test the contrasting hypothesis, that local habitat units are not interchangeable in their habitat attributes, but are instead dependent on variation in surrounding habitat structure at both patch- and landscape levels. As the statistical approaches needed to implement such hierarchical causal models are observation-intensive, we utilise very high resolution (VHR) Earth Observation (EO) images to rapidly generate fine-grained measures of habitat patch internal heterogeneities over large spatial extents. We use linear mixed-effects models to test whether these remotely-sensed proxies for habitat quality were influenced by surrounding patch or landscape structure. The results demonstrate the significant influence of surrounding patch and landscape context on local habitat quality. They further indicate that such an influence can be direct, when a landscape variable alone influences the habitat structure variable, and/or indirect when the landscape and patch attributes have a conjoined effect on the response variable. We conclude that a substantial degree of interaction among spatial configuration effects is likely to be the norm in determining the ecological consequences of habitat fragmentation, thus corroborating the notion of the spatial context dependence of habitat quality.

Patch tests with fragrance mix II and its components.

PubMed

Pónyai, Györgyi; Németh, Ilona; Altmayer, Anita; Nagy, Gabriella; Irinyi, Beatrix; Battyáni, Zita; Temesvári, Erzsébet

2012-01-01

Fragrance mix II (FM II) was initiated to detect contact hypersenstitivity (CH) to fragrances that could not have been identified previously. The aim of this multicenter study was to map the frequency of CH to FM II and its components in Hungary. Six centers participated in the survey from 2009 to 2010. A total off 565 patients (434 women and 131 men) with former skin symptoms provoked by scented products were patch tested. The tests were performed with Brial GmbH D-Greven allergens. In the environmental patch test series, FM II, FM I, Myroxylon pereirae, colophonium, wood-tar mix, propolis, and sesquiterpene lactone mix were tested as fragrance allergens. The FM II components (citral, farnesol, coumarin, citronellol, α-hexyl-cinnamaldehyde, and hydroxy-isohexyl-3-cyclohexene-carboxaldehyde [Lyral]) were also tested. Contact hypersenstitivity to any fragrances was detected in 28.8%, to FM II in 17.2% of the patients. Contact hypersenstitivity to hydroxy-isohexyl-3-cyclohexene-carboxaldehyde was observed in 7.3%, to coumarin in 5.1%, to α-hexyl-cinnamaldehyde in 3.5%, to citral in 3.4%, to farnesol in 2.5%, and to citronellol in 1.2%. Of the FM II-positive cases, 48.4% showed isolated CH reaction. The frequency of CH to FM II is 17.2% in the tested, selected Hungarian population. The CH to FM II and its components could not have been revealed without the present test materials.

Supplemental tests in the evaluation of occupational hand dermatitis in soldiers.

PubMed

Wolf, R; Movshowitz, M; Brenner, S

1996-03-01

Hand dermatitis in soldiers is a considerable problem. The purpose of the study was to evaluate appropriate screening tests to improve the diagnosis of hand dermatitis in soldiers. A group of 111 soldiers with occupational dermatitis from contact with fuels and oils underwent "tailored patch tests" with allergens relevant to their field of work and their environment. The control group consisted of 24 soldiers with various jobs similar to those of civilian life, who had not been exposed to oils and fuels. Seventy-three civilian patients, attending the clinic for patch testing, were also included. Twenty soldiers, who had a history of intensive contact with oil and fuels, but no contact dermatitis, and who were admitted because of various skin diseases (fungal infections, acne, etc.) also underwent the supplemental testing and served as an additional control group. Of the soldiers, 31 (29%) showed one or more positive skin tests of the oil series and 30 patients of this group one or more positive reactions to the standard patch tests trays. No patient of the control groups had a positive test to the oil series. Our results show the value of the supplementary tests as a first-step screening test for detection of oil allergy in soldiers and automobile-mechanics or in workers handling other gasoline- or diesel-powered engineering equipment. The test method appears to be practical, easy to perform, reliable and giving clear and accurate results, with a negligible rate of false positive reactions.

Hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral®) as allergen: experience from a contact dermatitis unit.

PubMed

Carvalho, Rodrigo; Maio, Paula; Amaro, Cristina; Santos, Raquel; Cardoso, Jorge

2011-09-01

Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC)-Lyral® is a widely used synthetic fragrance found in personal care and household products. It is an aldehyde, lipophilic enough to penetrate the skin and is a frequent cause of contact sensitization. Describe the frequency of contact allergy to HICC in a Contact Dermatitis Unit, after its inclusion in baseline patch test series. A retrospective study including all patients submitted to patch test, from January 2007 to December 2009. Over a 3-year period, 629 consecutive patients were patch tested. The frequency of positive reactions to HICC was 2.7% (17/629). Of the positive patients, 35% (6/17) gave a history of atopy, 58.8% (10/17) had eczema on the face and neck, 23.5% (4/17) on the hands, 23.5% (4/17) in the axillae, 17.6% (3/17) on the trunk and 6% (3/17) had generalized eczema. All patients were patch positive for more than one allergen: all (17/17) positive to fragrance Mix 2 (FM2); 47% of the patients (8/17) positive to fragrance Mix 1 (FM1); and 23.5% of the patients (4/17) positive to Balsam of Peru. In 94% (16/17) of cases, the reaction was judged to be of current relevance. The frequency of positive reactions to HICC of 2.7% found in our population is according to what is described in several European reports, where HICC is still widely used as a fragrance ingredient. In contrast, in North America, the prevalence is lower. All the patients were positive also to FM2. The association found between reactions to FM1 and HICC is also commonly reported and could represent a concomitant sensitization following increased exposure to fragrance allergens. These data confirm the importance of HICC introduction in the baseline patch test series.

Identifying preferred habitats of samango monkeys (Cercopithecus (nictitans) mitis, erythrarchus) through patch use.

PubMed

Emerson, Sara E; Brown, Joel S

2013-10-26

To examine habitat preferences of two groups of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) in the Soutpansberg, South Africa, we used experimental food patches in fragments of tall forest and in bordering secondary growth short forest. Additionally, to test for the impacts of group cohesion and movement on habitat use, we tested for the interaction of space and time in our analyses of foraging intensity in the experimental food patches placed throughout the home ranges of the two groups. We expected the monkeys to harvest the most from patches in tall forest habitats and the least from patches in short forest. Further, because the monkeys move through their habitats in groups, we expected to see group cohesion effects illustrated by daily spatial variation in the monkeys' use of widespread foraging grids. In the forest height experiments, the two groups differed in their foraging responses, with 8% greater foraging overall for one group. However, forest height did not significantly impact foraging in either group, meaning that, given feeding opportunities, samango monkeys are able to utilize secondary growth forest. For one group, missed opportunity costs of staying with the group appeared through the statistical interaction of day with foraging location (the monkeys did not always spread out to take advantage of all available food patches). In several subsequent experiments in widespread grids, significant daily spatial variation in foraging occurred, pointing to spatial cohesion during group movement as likely being an important predictor of habitat use. For an individual social forager, staying with the group may be more important than habitat type in driving habitat selection. Copyright © 2013 Elsevier B.V. All rights reserved.

Training a cell-level classifier for detecting basal-cell carcinoma by combining human visual attention maps with low-level handcrafted features

PubMed Central

Corredor, Germán; Whitney, Jon; Arias, Viviana; Madabhushi, Anant; Romero, Eduardo

2017-01-01

Abstract. Computational histomorphometric approaches typically use low-level image features for building machine learning classifiers. However, these approaches usually ignore high-level expert knowledge. A computational model (M_im) combines low-, mid-, and high-level image information to predict the likelihood of cancer in whole slide images. Handcrafted low- and mid-level features are computed from area, color, and spatial nuclei distributions. High-level information is implicitly captured from the recorded navigations of pathologists while exploring whole slide images during diagnostic tasks. This model was validated by predicting the presence of cancer in a set of unseen fields of view. The available database was composed of 24 cases of basal-cell carcinoma, from which 17 served to estimate the model parameters and the remaining 7 comprised the evaluation set. A total of 274 fields of view of size 1024×1024  pixels were extracted from the evaluation set. Then 176 patches from this set were used to train a support vector machine classifier to predict the presence of cancer on a patch-by-patch basis while the remaining 98 image patches were used for independent testing, ensuring that the training and test sets do not comprise patches from the same patient. A baseline model (M_ex) estimated the cancer likelihood for each of the image patches. M_ex uses the same visual features as M_im, but its weights are estimated from nuclei manually labeled as cancerous or noncancerous by a pathologist. M_im achieved an accuracy of 74.49% and an F-measure of 80.31%, while M_ex yielded corresponding accuracy and F-measures of 73.47% and 77.97%, respectively. PMID:28382314

Microwave Power for Smart Membrane Actuators

NASA Technical Reports Server (NTRS)

Choi, Sang H.; Song, Kyo D.; Golembiewski, Walter T.; Chu, Sang-Hyon; King, Glen C.

2002-01-01

The concept of microwave-driven smart membrane actuators is envisioned as the best option to alleviate the complexity associated with hard-wired control circuitry. A large, ultra-light space structure, such as solar sails and Gossamer spacecrafts, requires a distribution of power into individual membrane actuators to control them in an effective way. A patch rectenna array with a high voltage output was developed to drive smart membrane actuators. Networked patch rectenna array receives and converts microwave power into a DC power for an array of smart actuators. To use microwave power effectively, the concept of a power allocation and distribution (PAD) circuit is developed and tested for networking a rectenna/actuator patch array. For the future development, the PAD circuit could be imbedded into a single embodiment of rectenna and actuator array with the thin-film microcircuit embodiment. Preliminary design and fabrication of PAD circuitry that consists of a sixteen nodal elements were made for laboratory testing.

Formulation and Evaluation of a Novel Adhesive Film for Use in Composite Patch Repair

NASA Astrophysics Data System (ADS)

Tsamasphyros, G.; Kalkanis, K.; Maroulas, P.; Anthoulis, G. I.; Grigoryeva, O.

2008-08-01

The current work focuses on the testing of a novel material used as an adhesive film in Composite Patch Repair (CPR). A series of Differential Scanning Calorimetry (DSC) results along with various curing cycles not only led to the optimum material composition but also demonstrated the compatibility to the composite pre-impregnated patches. This in turn was subjected to mechanical testing including shear strength measurements. The substrate was chosen to be 2017 T4 aluminium alloy which is customarily used in the aerospace industry, taking into account that CPR is a technique mainly applied in this field. The subsequent surface preparation of the specimens was investigated for the specified context resulting to the selection of the Ferric Sulphate Sulphuric acid etching process. Finally, a series of specimens representing actual skin repairs were created and subjected to cyclic loading, specifying the suitability of the novel material, compared to commercially available materials.

Fatigue behavior of a thermally-activated NiTiNb SMA-FRP patch

NASA Astrophysics Data System (ADS)

El-Tahan, M.; Dawood, M.

2016-01-01

This paper presents the details of an experimental study that was conducted to characterize the fatigue behavior of a thermally-activated shape memory alloy (SMA)/carbon fiber reinforced polymer (CFRP) patch that can be used to repair cracked steel members. A total of 14 thermally-activated patches were fabricated and tested to evaluate the stability of the prestress under fatigue loading. The parameters considered in this study are the prestress level in the nickel-titanium-niobium SMA wires and the applied force range. An empirical model to predict the degradation of the prestress is also presented. The results indicate that patches for which the maximum applied loads in a fatigue cycle did not cause debonding of the SMA wires from the CFRP sustained two million loading cycles with less than 20% degradation of the prestress.

Conductive polymer nanotube patch for fast and controlled ex vivo transdermal drug delivery.

PubMed

Nguyen, Thao M; Lee, Sebin; Lee, Sang Bok

2014-10-01

To uptake and release hydrophilic model drugs and insulin in a novel conductive polymer (CP) nanotube transdermal patch. The externally controlled transdermal delivery of model drugs and insulin were tested ex vivo and results were compared with CP films. The unique intrinsic properties of CPs provide electrostatic interaction between the model drugs and polymer backbone. When a pulsed potential was applied, the drug delivery release profile mimics that of injection delivery. With a constant potential applied, the release rate constants of the patch system were up to three-times faster than the control (0 V) and released approximately 80% more drug molecules over 24 h. The CP nanotube transdermal patch represents a new and promising drug method, specifically for hydrophilic molecules, which have been a large obstacle for conventional transdermal drug delivery systems.

PatchSurfers: Two methods for local molecular property-based binding ligand prediction.

PubMed

Shin, Woong-Hee; Bures, Mark Gregory; Kihara, Daisuke

2016-01-15

Protein function prediction is an active area of research in computational biology. Function prediction can help biologists make hypotheses for characterization of genes and help interpret biological assays, and thus is a productive area for collaboration between experimental and computational biologists. Among various function prediction methods, predicting binding ligand molecules for a target protein is an important class because ligand binding events for a protein are usually closely intertwined with the proteins' biological function, and also because predicted binding ligands can often be directly tested by biochemical assays. Binding ligand prediction methods can be classified into two types: those which are based on protein-protein (or pocket-pocket) comparison, and those that compare a target pocket directly to ligands. Recently, our group proposed two computational binding ligand prediction methods, Patch-Surfer, which is a pocket-pocket comparison method, and PL-PatchSurfer, which compares a pocket to ligand molecules. The two programs apply surface patch-based descriptions to calculate similarity or complementarity between molecules. A surface patch is characterized by physicochemical properties such as shape, hydrophobicity, and electrostatic potentials. These properties on the surface are represented using three-dimensional Zernike descriptors (3DZD), which are based on a series expansion of a 3 dimensional function. Utilizing 3DZD for describing the physicochemical properties has two main advantages: (1) rotational invariance and (2) fast comparison. Here, we introduce Patch-Surfer and PL-PatchSurfer with an emphasis on PL-PatchSurfer, which is more recently developed. Illustrative examples of PL-PatchSurfer performance on binding ligand prediction as well as virtual drug screening are also provided. Copyright © 2015 Elsevier Inc. All rights reserved.

Measuring wearing times of glasses and ocular patches using a thermosensor device from orthodontics.

PubMed

Januschowski, Kai; Bechtold, Till E; Schott, Timm C; Huelber-Januschowski, Maren S; Blumenstock, Gunnar; Bartz-Schmidt, Karl-Ulrich; Besch, Dorothea; Schramm, Charlotte

2013-12-01

Amblyopia is one of the most common visual disorders in children. The risk of severe visual impairment on the healthy eye is doubled in patients with amblyopia. If detected early enough, the chances of visual rehabilitation are good. Treatment consists of refractive correction and occlusion of the dominant eye. Patient compliance is an important factor and can be monitored using thermosensors. It was the goal of our study to give proof of the principle that the wearing times of glasses and patches can be measured using a comparatively small and commercially available microsensor. Agreement between wearing times protocols of ocular patching/refractive correction and temperature measurements of thermosensors attached to the patches or glasses of three individuals were analysed using the Bland-Altman method. It was also analysed whether blinded persons could distinguish between temperature curves of patches and glasses, or temperature curves of an incubator or while worn in a pocket. The temperatures picked up by the microsensors indicate the beginning and the end wearing times of either glasses or ocular patches through steep temperature difference and a distinct temperature curve during measurements. Although blinded test persons were able to cleary distinguish between temperature profiles from incubator/pocket measurements compared to glasses/patching, glasses and patching curves could be discriminated correctly in only 50%. Differences between wearing time protocols and temperature measurements were within the limits of agreement as stated by the Bland-Altman plots. The TheraMon(®) microsensor can reliably measure wearing times of glasses and ocular patches without making the wearer uncomfortable, although the data are not unquestionable, especially in higher surrounding temperatures. Further studies on a larger number of individuals with different wearing profiles are needed. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Development of mucoadhesive patches for buccal administration of carvedilol.

PubMed

Vishnu, Y Vamshi; Chandrasekhar, K; Ramesh, G; Rao, Y Madhusudan

2007-01-01

A buccal patch for systemic administration of carvedilol in the oral cavity has been developed using two different mucoadhesive polymers. The formulations were tested for in vitro drug permeation studies, buccal absorption test, in vitro release studies, moisture absorption studies and in vitro bioadhesion studies. The physicochemical interactions between carvedilol and polymers were investigated by Fourier transform infrared (FTIR) Spectroscopy. According to FTIR the drug did not show any evidence of an interaction with the polymers used and was present in an unchanged state. XRD studies reveal that the drug is in crystalline state in the polymer matrix. The results indicate that suitable bioadhesive buccal patches with desired permeability could be prepared. Bioavailability studies in healthy pigs reveal that carvedilol has got good buccal absorption. The bioavailability of carvedilol from buccal patches has increased 2.29 folds when compared to that of oral solution. The formulation AC5 (HPMC E 15) shows 84.85 + 0.089% release and 38.69 + 6.61% permeated through porcine buccal membrane in 4 hr. The basic pharmacokinetic parameters like the C(max), T(max) and AUC(total) were calculated and showed statistically significant difference (P<0.05) when given by buccal route compared to that of oral solution.

Microwave-Driven Multifunctional Capability of Membrane Structures

NASA Technical Reports Server (NTRS)

Choi, Sang H.; Chu, Sang-Hyong; Song, Kyo D.; King, Glen C.

2002-01-01

A large, ultra lightweight space structure, such as solar sails and Gossamer spacecrafts, requires a distributed power source to alleviate wire networks, unlike the localized on-board power infrastructures typically found in most small spacecrafts. The concept of microwave-driven multifunctional capability for membrane structures is envisioned as the best option to alleviate the complexity associated with hard-wired control circuitry and on-board power infrastructures. A rectenna array based on a patch configuration for high voltage output was developed to drive membrane actuators, sensors, probes, or other devices. Networked patch rectenna array receives and converts microwave power into a DC power for an array of smart actuators. To use microwave power effectively, the concept of a power allocation and distribution (PAD) circuit is adopted for networking a rectenna/actuator patch array. The use of patch rectennas adds a significant amount of rigidity to membrane flexibility and they are relatively heavy. A dipole rectenna array (DRA) appears to be ideal for thin-film membrane structures, since DRA is flexible and light. Preliminary design and fabrication of PAD circuitry that consists of a few nodal elements were made for laboratory testing. The networked actuators were tested to correlate the network coupling effect, power allocation and distribution, and response time.

Riparian rehabilitation using vegetation patches: field and laboratory investigations linking hydrology, vegetation and geomorphology

NASA Astrophysics Data System (ADS)

Rodriguez, J. F.; Gorrick, S.

2010-12-01

We present results of a riparian revegetation project on an oversized sand stream in eastern Australia. The Widden Brook in New South Wales has undergone extensive widening due to extraordinary floods in the 1950’s and is currently showing some signs of recovery. These include emergence of pool-riffle structure and stabilization of stream width, which are the result of upstream sediment control, riparian revegetation and livestock exclusion. Revegetation of a mild bend was carried out in 2004 using native plants in an arrangement that consisted of three vegetation patches. The same arrangement was tested in a reduced scale model in the laboratory, where extensive measurements of flow, sediment and bed changes provided insight into the links between hydrology, vegetation and geomorphology. Laboratory tests also included runs without vegetation and with a continuous vegetation cover. In terms of bank stability, the patches provided as much protection as the continuous vegetation. Based on the experiments, a series of analytical relationships were developed to help guide the design of vegetation patches focusing on the geomorphic stability of the whole reach instead of concentrating only on the near bank effects.

Application of level set method to optimal vibration control of plate structures

NASA Astrophysics Data System (ADS)

Ansari, M.; Khajepour, A.; Esmailzadeh, E.

2013-02-01

Vibration control plays a crucial role in many structures, especially in the lightweight ones. One of the most commonly practiced method to suppress the undesirable vibration of structures is to attach patches of the constrained layer damping (CLD) onto the surface of the structure. In order to consider the weight efficiency of a structure, the best shapes and locations of the CLD patches should be determined to achieve the optimum vibration suppression with minimum usage of the CLD patches. This paper proposes a novel topology optimization technique that can determine the best shape and location of the applied CLD patches, simultaneously. Passive vibration control is formulated in the context of the level set method, which is a numerical technique to track shapes and locations concurrently. The optimal damping set could be found in a structure, in its fundamental vibration mode, such that the maximum modal loss factor of the system is achieved. Two different plate structures will be considered and the damping patches will be optimally located on them. At the same time, the best shapes of the damping patches will be determined too. In one example, the numerical results will be compared with those obtained from the experimental tests to validate the accuracy of the proposed method. This comparison reveals the effectiveness of the level set approach in finding the optimum shape and location of the CLD patches.

Predicting nucleic acid binding interfaces from structural models of proteins

PubMed Central

Dror, Iris; Shazman, Shula; Mukherjee, Srayanta; Zhang, Yang; Glaser, Fabian; Mandel-Gutfreund, Yael

2011-01-01

The function of DNA- and RNA-binding proteins can be inferred from the characterization and accurate prediction of their binding interfaces. However the main pitfall of various structure-based methods for predicting nucleic acid binding function is that they are all limited to a relatively small number of proteins for which high-resolution three dimensional structures are available. In this study, we developed a pipeline for extracting functional electrostatic patches from surfaces of protein structural models, obtained using the I-TASSER protein structure predictor. The largest positive patches are extracted from the protein surface using the patchfinder algorithm. We show that functional electrostatic patches extracted from an ensemble of structural models highly overlap the patches extracted from high-resolution structures. Furthermore, by testing our pipeline on a set of 55 known nucleic acid binding proteins for which I-TASSER produces high-quality models, we show that the method accurately identifies the nucleic acids binding interface on structural models of proteins. Employing a combined patch approach we show that patches extracted from an ensemble of models better predicts the real nucleic acid binding interfaces compared to patches extracted from independent models. Overall, these results suggest that combining information from a collection of low-resolution structural models could be a valuable approach for functional annotation. We suggest that our method will be further applicable for predicting other functional surfaces of proteins with unknown structure. PMID:22086767

Multi-Band Miniaturized Patch Antennas for a Compact, Shielded Microwave Breast Imaging Array.

PubMed

Aguilar, Suzette M; Al-Joumayly, Mudar A; Burfeindt, Matthew J; Behdad, Nader; Hagness, Susan C

2013-12-18

We present a comprehensive study of a class of multi-band miniaturized patch antennas designed for use in a 3D enclosed sensor array for microwave breast imaging. Miniaturization and multi-band operation are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in symmetric radiation patterns and similar radiation characteristics at all frequencies of operation. Prototypes were fabricated and tested in a biocompatible immersion medium. Excellent agreement was obtained between simulations and measurements. The trade-off between miniaturization and radiation efficiency within this class of patch antennas is explored via a numerical analysis of the effects of the location and number of slots, as well as the thickness and permittivity of the dielectric substrate, on the resonant frequencies and gain. Additionally, we compare 3D quantitative microwave breast imaging performance achieved with two different enclosed arrays of slot-loaded miniaturized patch antennas. Simulated array measurements were obtained for a 3D anatomically realistic numerical breast phantom. The reconstructed breast images generated from miniaturized patch array data suggest that, for the realistic noise power levels assumed in this study, the variations in gain observed across this class of multi-band patch antennas do not significantly impact the overall image quality. We conclude that these miniaturized antennas are promising candidates as compact array elements for shielded, multi-frequency microwave breast imaging systems.

The evolution of colour pattern complexity: selection for conspicuousness favours contrasting within-body colour combinations in lizards.

PubMed

Pérez I de Lanuza, G; Font, E

2016-05-01

Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis, we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long-wavelength-based) and lateral (short-wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

A randomized trial comparing part-time patching with observation for children 3 to 10 years of age with intermittent exotropia.

PubMed

Cotter, Susan A; Mohney, Brian G; Chandler, Danielle L; Holmes, Jonathan M; Repka, Michael X; Melia, Michele; Wallace, David K; Beck, Roy W; Birch, Eileen E; Kraker, Raymond T; Tamkins, Susanna M; Miller, Aaron M; Sala, Nicholas A; Glaser, Stephen R

2014-12-01

To determine the effectiveness of prescribed part-time patching for treatment of intermittent exotropia (IXT) in children. Multicenter, randomized clinical trial. Three hundred fifty-eight children 3 to <11 years of age with previously untreated (except for refractive correction) IXT and near stereoacuity of 400 seconds of arc or better were enrolled. Intermittent exotropia met the following criteria: (1) IXT at distance OR constant exotropia at distance and either IXT or exophoria at near; (2) exodeviation (tropia or phoria) of at least 15 prism diopters (PD) at distance or near by prism and alternate cover test (PACT); and (3) exodeviation of at least 10 PD at distance by PACT. Participants were assigned randomly either to observation (no treatment for 6 months) or to patching for 3 hours daily for 5 months, with a 1-month washout period of no patching before the 6-month primary outcome examination. The primary outcome was deterioration at either the 3-month or the 6-month follow-up visit, defined as: (1) constant exotropia measuring at least 10 PD at distance and near by simultaneous prism and cover test, and/or (2) near stereoacuity decreased by at least 2 octaves from baseline, both assessed by a masked examiner and confirmed by a retest. Participants who were prescribed any nonrandomized treatment without first meeting either deterioration criteria also were counted as having deteriorated. Of the 324 participants (91%) completing the 6-month primary outcome examination, deterioration occurred in 10 of the 165 participants (6.1%) in the observation group (3 of these 10 started treatment without meeting deterioration criteria) and in 1 of the 159 participants (0.6%) in the part-time patching group (difference, 5.4%; lower limit of 1-sided exact 95% confidence interval, 2.0%; P = 0.004, 1-sided hypothesis test). Deterioration of previously untreated childhood IXT over a 6-month period is uncommon with or without patching treatment. Although there is a slightly lower deterioration rate with patching, both management approaches are reasonable for treating children 3 to 10 years of age with IXT. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Calycophyllum spruceanum BENTH ameliorates acute inflammation in mice.

PubMed

da Silva, Ana Paula Azevedo Barros; Amorim, Renata Morais Ferreira; de Freitas Lopes, Roberta; Mota, Mário Rogério Lima; da Silva, Felipe Moura Araújo; Koolen, Hector Henrique Ferreira; Lima, Emerson Silva; Assreuy, Ana Maria S; da Cunha, Renildo Moura

2018-06-12

Calycophyllum spruceanum (Benth.) Hook. F. ex K. Schum. is widely distributed in the Amazonian region of Brazil, where it is popularly known as "mulateiro", "pau-mulato", "pau-mulato-de-várzea", "escorrega-macaco" or "pau-marfim". Preparations of C. spruceanum barks are used in the form of tea, poultice or skin patches to treat stomach diseases, skin inflammation and uterus tumors. To investigate in vivo the antinociceptive and anti-inflammatory activities of the hydroalcoholic extract of Calycophyllum spruceanum barks (HECSb) in order to validate its popular usage in inflammatory conditions. Chemical analysis of HECSb was performed using the UHPLC-MS system. Mice were treated per oral with HECSb (5-5000 mg/kg) and evaluated for acute toxicity (during 15 days); motor activity (Rota rod test); body weight (up to 72 h); antinociceptive activity: writhes induced by 0.8% acetic acid; paw licking induced by 2.5% formalin; paw withdrawal (von Frey test) induced by carrageenan (300 μg) or PGE2 (100 ng); anti-inflammatory (paw edema model). For histopathological analysis subplantar tissue fragments were collected 1 h after paw edema induction. HECSb chemical analysis revealed the presence of caffeoylquinic derivatives, small organic acids, and phenolic compounds. HECSb showed antinociceptive effect, reducing the number of acetic acid-induced writhes by 72% at 120 mg/kg, paw licking (phase 2- Formalin test) by 33% at 60 mg/kg and 49% at 120 mg/kg; and paw withdrawal elicited by carrageenan (53% at 120 mg/kg) and PGE2 (120 mg/kg) at 0.5 h (48%) and 1 h (45%). HECSb (120 mg/kg) also inhibited the paw edema elicited both by carrageenan (48%) and PGE2 (92%). Histopathological analysis (leukocyte infiltration, edema, focal areas of hemorrhage, vascular congestion) of HECSb treatment at 120 mg/kg demonstrated normal morphology [median 0 (0,1)] compared to PGE2, showing severe alterations [median 3 (2,3); p = 0,0035]. HECSb did not induce acute toxicity nor altered body mass or motor coordination. HECSb shows antinociceptive and anti-inflammatory effect in mice without inducing apparent acute toxicity. Copyright © 2018 Elsevier B.V. All rights reserved.

Photoelectrochemical modulation of neuronal activity with free-standing coaxial silicon nanowires

NASA Astrophysics Data System (ADS)

Parameswaran, Ramya; Carvalho-de-Souza, João L.; Jiang, Yuanwen; Burke, Michael J.; Zimmerman, John F.; Koehler, Kelliann; Phillips, Andrew W.; Yi, Jaeseok; Adams, Erin J.; Bezanilla, Francisco; Tian, Bozhi

2018-02-01

Optical methods for modulating cellular behaviour are promising for both fundamental and clinical applications. However, most available methods are either mechanically invasive, require genetic manipulation of target cells or cannot provide subcellular specificity. Here, we address all these issues by showing optical neuromodulation with free-standing coaxial p-type/intrinsic/n-type silicon nanowires. We reveal the presence of atomic gold on the nanowire surfaces, likely due to gold diffusion during the material growth. To evaluate how surface gold impacts the photoelectrochemical properties of single nanowires, we used modified quartz pipettes from a patch clamp and recorded sustained cathodic photocurrents from single nanowires. We show that these currents can elicit action potentials in primary rat dorsal root ganglion neurons through a primarily atomic gold-enhanced photoelectrochemical process.

Epidemic of Isothiazolinone Allergy in North America: Prevalence Data From the North American Contact Dermatitis Group, 2013-2014.

PubMed

Zirwas, Matthew J; Hamann, Dathan; Warshaw, Erin M; Maibach, Howard I; Taylor, James S; Sasseville, Denis; DeKoven, Joel G; Fransway, Anthony F; Mathias, C G Toby; Zug, Kathryn A; DeLeo, Vincent A; Fowler, Joseph F; Marks, James G; Pratt, Melanie D; Belsito, Donald V

Preservative sensitivity patterns evolve with changing use patterns in products. During the last decade, the use of methylisothiazolinone (MI) at higher concentrations in both leave-on and rinse-off products has significantly increased. This is the first North American Contact Dermatitis Group reporting cycle that includes both methylchloroisothiazolinone (MCI)/MI and MI data. The aim of this study was to report the prevalence of isothiazolinone allergy (MCI/MI and MI) in the North American Contact Dermatitis Group patch-test population from January 1, 2013, to December 31, 2014. At 13 centers in North America, 4860 patients were patch tested in a standardized manner with a series of 70 allergens, including MCI/MI 0.01% aqueous (aq) and MI 0.2% aq. Three hundred five patients (6.3%) had a positive reaction to MCI/MI; this is a significant increase from the previous cycle (5.0%, 2011-2012; P = 0.011). Five hundred twenty-one patients (10.7%) had a positive reaction to MI. These 2 isothiazolinones were among the most common preservative allergens in the 2013 to 2014 cycle; 11.9% of patch-tested individuals were allergic to 1 or both isothiazolinones. Individuals with MCI/MI and MI allergy were significantly more likely to have occupationally related skin disease (P < 0.0001) and hand dermatitis (P < 0.0001, P = 0.0474). The epidemic of isothiazolinone sensitivity documented in Europe is now in North America. Patch testing with only MCI/MI 0.01% aq will miss approximately half of isothiazolinone allergy cases, whereas testing with only MI 0.2% aq will miss approximately 10% of isothiazolinone allergy cases.

Essential Oils, Part IV: Contact Allergy.

PubMed

de Groot, Anton C; Schmidt, Erich

2016-01-01

Nearly 80 essential oils (including 2 jasmine absolutes) have caused contact allergy. Fifty-five of these have been tested in consecutive patients suspected of contact dermatitis, and nine (laurel, turpentine, orange, tea tree, citronella, ylang-ylang, sandalwood, clove, and costus root) showed greater than 2% positive patch test reactions. Relevance data are generally missing or inadequate. Most reactions are caused by application of pure oils or high-concentration products. The clinical picture depends on the responsible product. Occupational contact dermatitis may occur in professionals performing massages. The (possible) allergens in essential oils are discussed. Several test allergens are available, but patients should preferably be tested with their own products. Co-reactivity with other essential oils and the fragrance mix is frequent, which may partly be explained by common ingredients. Patch test concentrations for essential oils are suggested.

Allergic contact dermatitis pattern in Kuwait: nickel leads the pack. In-depth analysis of nickel allergy based on the results from a large prospective patch test series report

PubMed Central

Almutawa, Fahad

2017-01-01

Introduction Contact dermatitis is a relatively common dermatosis reported among several population groups from all around the globe. However, the data from Kuwait is unavailable. Patch tests are essential for the diagnosis of contact sensitization. Aim To determine a relative frequency and pattern of sensitizers to different allergens in patients of suspected contact dermatitis in Kuwait and, also to study the role of the commonest sensitizer in detail. Material and methods Patch tests were performed in 2461 consecutive patients with a clinical diagnosis of contact dermatitis seen at our hospital between September 1, 2014 and August 31, 2015. Out of the total of 1381 (56.1%) patients with positive patch test results to at least one allergen, 546 (22.2%) patients with a single positive reaction to nickel only (single largest sensitizer) were selected as the study population for further detailed analysis. Results At least one positive patch test reaction was found in 1381 (56.12%) patients. Nickel was found to be the most common sensitizer seen in 546 (40%) patients. The mean age was 37.3 ±13.8 years and the mean duration of disease was 27.3 ±13.8 months. Most (387/546) patients sensitized were females. The forearms/hands and wrists were the most prevalent sites (52.56% of the participants). In 58.91% of women, dermatitis was more often confined to other sites, mostly ears and the neck due to earrings and necklaces. Just more than half of the number (51.09%) of nickel allergic patients were found in the age group of 15–25 years. Hairdressers/beauticians were the most affected group followed by house workers (housewives, cleaners, housekeepers). Conclusions Nickel is the single most common sensitizer found in our patients, and female sex, young age, occupation with long hours of contact to nickel are high risk factors. We recommend that a directive, which limits the release of nickel from products with extended skin contact, be approved in Kuwait. PMID:28670248

Cross-reactions among hair dye allergens.

PubMed

Basketter, David A; English, John

2009-01-01

p-Phenylenediamine (PPD) is an important hair dye allergen, but there remains a reasonable suspicion that other hair dye chemicals may also be responsible for a proportion of the clinical burden of hair dye allergy. To assess to what extent presently assessed additional patch test agents contribute to the diagnosis of non-PPD hair dye allergy. A retrospective analysis was conducted of patch test results with hair dye allergens, focusing on the extent to which patients who were positive for allergic reactions to other hair dye allergens also had a concomitant positive reaction to PPD. For the hair dye allergens other than p-toluenediamine (PTD), reactions in the absence of a concomitant positive reaction to PPD were very rare. Positive reactors to PTD were also positive for reactions to PPD in 5 of every 6 cases. Pyrogallol positives often occurred in the absence of a PPD positive, but were never judged to be of clinical relevance. Hair dye chemicals other than PPD may be of importance, but the presently tested materials, with the possible exception of PTD, are normally positive only when a PPD-positive reaction is also present, suggesting that their use in patch testing in hair dye allergy is likely to be of limited value.

Principles and methodology for identification of fragrance allergens in consumer products.

PubMed

Gimenez-Arnau, A; Gimenez-Arnau, E; Serra-Baldrich, E; Lepoittevin, J-P; Camarasa, J G

2002-12-01

Fragrances contain several hundreds of different chemicals, a few major and many minor, which are responsible for the complexity of the odour. Fragrances are a major cause of allergic contact dermatitis. As a diagnostic tool, the current fragrance mix is very useful though not ideal. A 50-year-old woman presented with a pruriginous, erythematous eruption, characterized by papules, vesicles, exudation and crusting over the neck and chest. With the suspicion of fragrance allergy, patch testing was performed. Initially, the only positive reaction observed was with her own eau de toilette named Woman. The TRUE Test fragrance mix patch test was negative. Chemical fractionation of Woman perfume concentrate was combined with a sequenced patch testing procedure and with structure-activity relationship studies. Ingredients supplied by the manufacturer were also included in the study. Benzophenone-2, Lyral, alpha-hexyl cinnamic aldehyde and alpha-damascone were found to be responsible for the patient's contact allergy to the commercial product. These substances contain chemical structural alerts giving them antigenic ability. The common use of new chemicals to manufacture fragrances, and the increased number of patients sensitive to them but with negative fragrance mix reactions, makes it necessary to identify new potential fragrance sensitizers in commercial products.

The Nano-Patch-Clamp Array: Microfabricated Glass Chips for High-Throughput Electrophysiology

NASA Astrophysics Data System (ADS)

Fertig, Niels

2003-03-01

Electrophysiology (i.e. patch clamping) remains the gold standard for pharmacological testing of putative ion channel active drugs (ICADs), but suffers from low throughput. A new ion channel screening technology based on microfabricated glass chip devices will be presented. The glass chips contain very fine apertures, which are used for whole-cell voltage clamp recordings as well as single channel recordings from mammalian cell lines. Chips containing multiple patch clamp wells will be used in a first bench-top device, which will allow perfusion and electrical readout of each well. This scalable technology will allow for automated, rapid and parallel screening on ion channel drug targets.

Human motion energy harvesting using a piezoelectric MFC patch.

PubMed

Bassani, Giulia; Filippeschi, Alessandro; Ruffaldi, Emanuele

2015-01-01

The improvements in efficiency of electronic components and miniaturization is quickly pushing wearable devices. Kinetic human energy harvesting is a way to power these components reducing the need of batteries replacement since walking or running is how humans already expend much of their daily energy. This work explores the case of kinetic energy from bending of a piezoelectric patch. For assessing the quality of the system, a testing setup has been designed and controlled by means of knee joint recordings obtained from a large motion dataset. The promising result of the chosen patch is an output power of 2.6μW associated to a run activity.

"Phase capture" in the perception of interpolated shape: cue combination and the influence function.

PubMed

Levi, Dennis M; Wing-Hong Li, Roger; Klein, Stanley A

2003-09-01

This study was concerned with what stimulus information observers use to judge the shape of simple objects. We used a string of four Gabor patches to define a contour. A fifth, center patch served as a test pattern. The observers' task was to judge the location of the test pattern relative to the contour. The contour was either a straight line, or an arc with positive or negative curvature (the radius of curvature was either 2 or 6 deg). We asked whether phase shifts in the inner or outer pairs of patches distributed along the contour influence the perceived shape. That is, we measured the phase shift influence function. We found that shifting the inner patches of the string by 0.25 cycle results in almost complete phase capture (attraction) at the smallest separation (2 lambda), and the capture effect falls off rapidly with separation. A 0.25 cycle shift of the outer pair of patches has a much smaller effect, in the opposite direction (repulsion). In our experiments, the contour is defined by two cues--the cue provided by the Gabor carrier (the 'feature' cue) and that defined by the Gaussian envelope (the 'envelope' cue). Our phase shift influence function can be thought of as a cue combination task. An ideal observer would weight the cues by the inverse variance of the two cues. The variance in each of these cues predicts the main features of our results quite accurately.

Pasture succession in the Neotropics: extending the nucleation hypothesis into a matrix discontinuity hypothesis.

PubMed

Peterson, Chris J; Dosch, Jerald J; Carson, Walter P

2014-08-01

The nucleation hypothesis appears to explain widespread patterns of succession in tropical pastures, specifically the tendency for isolated trees to promote woody species recruitment. Still, the nucleation hypothesis has usually been tested explicitly for only short durations and in some cases isolated trees fail to promote woody recruitment. Moreover, at times, nucleation occurs in other key habitat patches. Thus, we propose an extension, the matrix discontinuity hypothesis: woody colonization will occur in focal patches that function to mitigate the herbaceous vegetation effects, thus providing safe sites or regeneration niches. We tested predictions of the classical nucleation hypothesis, the matrix discontinuity hypothesis, and a distance from forest edge hypothesis, in five abandoned pastures in Costa Rica, across the first 11 years of succession. Our findings confirmed the matrix discontinuity hypothesis: specifically, rotting logs and steep slopes significantly enhanced woody colonization. Surprisingly, isolated trees did not consistently significantly enhance recruitment; only larger trees did so. Finally, woody recruitment consistently decreased with distance from forest. Our results as well as results from others suggest that the nucleation hypothesis needs to be broadened beyond its historical focus on isolated trees or patches; the matrix discontinuity hypothesis focuses attention on a suite of key patch types or microsites that promote woody species recruitment. We argue that any habitat discontinuities that ameliorate the inhibition by dense graminoid layers will be foci for recruitment. Such patches could easily be manipulated to speed the transition of pastures to closed canopy forests.

Computer-aided diagnosis of malignant mammograms using Zernike moments and SVM.

PubMed

Sharma, Shubhi; Khanna, Pritee

2015-02-01

This work is directed toward the development of a computer-aided diagnosis (CAD) system to detect abnormalities or suspicious areas in digital mammograms and classify them as malignant or nonmalignant. Original mammogram is preprocessed to separate the breast region from its background. To work on the suspicious area of the breast, region of interest (ROI) patches of a fixed size of 128×128 are extracted from the original large-sized digital mammograms. For training, patches are extracted manually from a preprocessed mammogram. For testing, patches are extracted from a highly dense area identified by clustering technique. For all extracted patches corresponding to a mammogram, Zernike moments of different orders are computed and stored as a feature vector. A support vector machine (SVM) is used to classify extracted ROI patches. The experimental study shows that the use of Zernike moments with order 20 and SVM classifier gives better results among other studies. The proposed system is tested on Image Retrieval In Medical Application (IRMA) reference dataset and Digital Database for Screening Mammography (DDSM) mammogram database. On IRMA reference dataset, it attains 99% sensitivity and 99% specificity, and on DDSM mammogram database, it obtained 97% sensitivity and 96% specificity. To verify the applicability of Zernike moments as a fitting texture descriptor, the performance of the proposed CAD system is compared with the other well-known texture descriptors namely gray-level co-occurrence matrix (GLCM) and discrete cosine transform (DCT).

Testing the role of patch openness as a causal mechanism for apparent area sensitivity in a grassland specialist.

PubMed

Keyel, Alexander C; Bauer, Carolyn M; Lattin, Christine R; Romero, L Michael; Reed, J Michael

2012-06-01

Area sensitivity, species being disproportionately present on larger habitat patches, has been identified in many taxa. We propose that some apparently area-sensitive species are actually responding to how open a habitat patch is, rather than to patch size. We tested this hypothesis for Bobolinks (Dolichonyx oryzivorus) by comparing density and occupancy to a novel openness index, patch area, and edge effects. Bobolink density and occupancy showed significant relationships with openness, but logistic models based on an openness occupancy threshold had greater explanatory power. Thresholds remained approximately consistent from June through August, and shifted to be more open in September. Variance partitioning supported the openness index as unique and relevant. We found no relationships between measures of body condition (body mass, body size, circulating corticosterone levels) and either openness or area. Our findings have implications for studies of area sensitivity, especially with regards to inconsistencies reported within species: specifically, (1) whether or not a study finds a species to be area sensitive may depend on whether small, open sites were sampled, and (2) area regressions were sensitive to observed densities at the largest sites, suggesting that variation in these fields could lead to inconsistent area sensitivity responses. Responses to openness may be a consequence of habitat selection mediated by predator effects. Finally, openness measures may have applications for predicting effects of habitat management or development, such as adding wind turbines, in open habitat.

Solvent Orange 60 is a potent contact sensitizer in occupational and everyday life.

PubMed

Linauskienė, Kotryna; Zimerson, Erik; Antelmi, Annarita; Bruze, Magnus; Hagvall, Lina; Hamnerius, Nils; Hauksson, Inese; Ryberg, Kristina; Isaksson, Marléne

2018-05-30

Solvent Orange (SO) 60 is a perinone-type dye that is often used in plastic materials such as spectacle frames and has been shown to cause contact allergy. The first case of SO 60 allergic contact dermatitis caused by spectacle frames was reported in 1999, and the second in 2011. We have recently seen 10 patients, of whom 6 developed dermatitis in the retroauricular/temporal area after wearing plastic spectacles. To report the cause of the dermatitis in the 10 patients and to describe our first case with occupational SO 60 contact allergy. In this retrospective study, patch test results of 10 patients, tested with the Swedish baseline series and our specific spectacle and/or plastic series, including SO 60 1.0% pet., in 2011-2017, were analysed and compared with data published earlier. Ten patients, 2 males and 8 females, aged 43 to 71 years, reacted positively to SO 60 1.0% pet., namely, 4 pensioners, 2 nurses, 1 office worker, 1 teacher, 1 shop assistant, and 1 unemployed person. Four of the patients had an atopic history. Patch test reactions varied from + to +++; some had spread >20 cm outside the test area, and consisted of erythematous, infiltrated skin with papules. Retesting of patient no. 1 with serial dilutions of SO 60 in acetone to pinpoint his level of reactivity showed positive reactions down to 1 ppm. Three patients reacted to the extracts of their earpieces. Gas chromatography-mass spectrometry was used to confirm the presence of SO 60 in 2 earpieces. SO 60 should be included in any spectacle patch test series that may be used. If there is a strong suspicion of contact allergy to SO 60 before patch testing, lowering the test concentration from 1.0% to 0.01% should be considered. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contact reactions to fragrances.

PubMed

Katsarou, A; Armenaka, M; Kalogeromitros, D; Koufou, V; Georgala, S

1999-05-01

The most common reaction to fragrances is contact dermatitis, a delayed hypersensitivity reaction; however, other reactions include immediate contact reactions (contact urticaria) and photo-allergic reactions. Fragrance mix (FM) and balsam of Peru (BP) are used to screen for fragrance allergy. To study the different types of allergic skin reactions to fragrance compounds. Delayed hypersensitivity reactions to FM and BP were studied in 4,975 patients with suspected contact dermatitis by routine patch testing interpreted at 48 and 96 hours. In 664 of the patients, patch tests were read at 30 minutes to evaluate for immediate (wheal-and-flare) contact reactions and again at 48 and 96 hours. Photopatch tests to FM were performed in 111 patients with suspected photo-allergic dermatitis. Delayed contact reactions to FM occurred in 6.6% of females and 5.4% of males and to BP in 3.9% of females and 4.1% of males. Analysis of data over time (12 study years) showed an increased trend for reactions to fragrances, particularly in males. Sensitivity to other contact allergens (polysensitivity) was found in 62% of patients and polysensitivity presented more often with generalized contact dermatitis. The most sensitizing components of the fragrance mix that were tested in 38 patients were cinnamic alcohol, oak moss, and cinnamic aldehyde. There were 112 immediate patch test reactions to FM and 113 to BP in 664 patients. Immediate contact reactions were followed by delayed contact reactions in 13.4% of patients for FM and 8.8% for BP, representing a significant increase in the frequency of delayed contact reactions. Patients with immediate contact reactions to fragrances did not have a higher incidence of atopy (25.9%). No cases of positive photopatch test reactions to FM were seen. Fragrances commonly cause both delayed and immediate patch test reactions and patients with immediate contact reactions have an increase in delayed contact reactions to the same allergen.

Theoretical oscillation frequencies for solar-type dwarfs from stellar models with 〈3D〉-atmospheres

NASA Astrophysics Data System (ADS)

Jørgensen, Andreas Christ Sølvsten; Weiss, Achim; Mosumgaard, Jakob Rørsted; Silva Aguirre, Victor; Sahlholdt, Christian Lundsgaard

2017-12-01

We present a new method for replacing the outermost layers of stellar models with interpolated atmospheres based on results from 3D simulations, in order to correct for structural inadequacies of these layers. This replacement is known as patching. Tests, based on 3D atmospheres from three different codes and interior models with different input physics, are performed. Using solar models, we investigate how different patching criteria affect the eigenfrequencies. These criteria include the depth, at which the replacement is performed, the quantity, on which the replacement is based, and the mismatch in Teff and log g between the un-patched model and patched 3D atmosphere. We find the eigenfrequencies to be unaltered by the patching depth deep within the adiabatic region, while changing the patching quantity or the employed atmosphere grid leads to frequency shifts that may exceed 1 μHz. Likewise, the eigenfrequencies are sensitive to mismatches in Teff or log g. A thorough investigation of the accuracy of a new scheme, for interpolating mean 3D stratifications within the atmosphere grids, is furthermore performed. Throughout large parts of the atmosphere grids, our interpolation scheme yields sufficiently accurate results for the purpose of asteroseismology. We apply our procedure in asteroseismic analyses of four Kepler stars and draw the same conclusions as in the solar case: Correcting for structural deficiencies lowers the eigenfrequencies, this correction is slightly sensitive to the patching criteria, and the remaining frequency discrepancy between models and observations is less frequency dependent. Our work shows the applicability and relevance of patching in asteroseismology.

Time-limited effects of emotional arousal on item and source memory.

PubMed

Wang, Bo; Sun, Bukuan

2015-01-01

Two experiments investigated the time-limited effects of emotional arousal on consolidation of item and source memory. In Experiment 1, participants memorized words (items) and the corresponding speakers (sources) and then took an immediate free recall test. Then they watched a neutral, positive, or negative video 5, 35, or 50 min after learning, and 24 hours later they took surprise memory tests. Experiment 2 was similar to Experiment 1 except that (a) a reality monitoring task was used; (b) elicitation delays of 5, 30, and 45 min were used; and (c) delayed memory tests were given 60 min after learning. Both experiments showed that, regardless of elicitation delay, emotional arousal did not enhance item recall memory. Second, both experiments showed that negative arousal enhanced delayed item recognition memory only at the medium elicitation delay, but not in the shorter or longer delays. Positive arousal enhanced performance only in Experiment 1. Third, regardless of elicitation delay, emotional arousal had little effect on source memory. These findings have implications for theories of emotion and memory, suggesting that emotion effects are contingent upon the nature of the memory task and elicitation delay.

Automated Coarse Registration of Point Clouds in 3d Urban Scenes Using Voxel Based Plane Constraint

NASA Astrophysics Data System (ADS)

Xu, Y.; Boerner, R.; Yao, W.; Hoegner, L.; Stilla, U.

2017-09-01

For obtaining a full coverage of 3D scans in a large-scale urban area, the registration between point clouds acquired via terrestrial laser scanning (TLS) is normally mandatory. However, due to the complex urban environment, the automatic registration of different scans is still a challenging problem. In this work, we propose an automatic marker free method for fast and coarse registration between point clouds using the geometric constrains of planar patches under a voxel structure. Our proposed method consists of four major steps: the voxelization of the point cloud, the approximation of planar patches, the matching of corresponding patches, and the estimation of transformation parameters. In the voxelization step, the point cloud of each scan is organized with a 3D voxel structure, by which the entire point cloud is partitioned into small individual patches. In the following step, we represent points of each voxel with the approximated plane function, and select those patches resembling planar surfaces. Afterwards, for matching the corresponding patches, a RANSAC-based strategy is applied. Among all the planar patches of a scan, we randomly select a planar patches set of three planar surfaces, in order to build a coordinate frame via their normal vectors and their intersection points. The transformation parameters between scans are calculated from these two coordinate frames. The planar patches set with its transformation parameters owning the largest number of coplanar patches are identified as the optimal candidate set for estimating the correct transformation parameters. The experimental results using TLS datasets of different scenes reveal that our proposed method can be both effective and efficient for the coarse registration task. Especially, for the fast orientation between scans, our proposed method can achieve a registration error of less than around 2 degrees using the testing datasets, and much more efficient than the classical baseline methods.

Optic nerve head component responses of the multifocal electroretinogram in MS.

PubMed

Frohman, Teresa C; Beh, Shin Chien; Saidha, Shiv; Schnurman, Zane; Conger, Darrel; Conger, Amy; Ratchford, John N; Lopez, Carmen; Galetta, Steven L; Calabresi, Peter A; Balcer, Laura J; Green, Ari J; Frohman, Elliot M

2013-08-06

To employ a novel stimulation paradigm in order to elicit multifocal electroretinography (mfERG)-induced optic nerve head component (ONHC) responses, believed to be contingent upon the transformation in electrical transmission properties of retinal ganglion cell axons from membrane to saltatory conduction mechanisms, as they traverse the lamina cribrosa and obtain oligodendrocyte myelin. We further sought to characterize abnormalities in ONHC responses in eyes from patients with multiple sclerosis (MS). In 10 normal subjects and 7 patients with MS (including eyes with and without a history of acute optic neuritis), we utilized a novel mfERG stimulation paradigm that included interleaved global flashes in order to elicit the ONHC responses from 103 retinal patches of pattern-reversal stimulation. The number of abnormal or absent ONHC responses was significantly increased in MS patient eyes compared to normal subject eyes (p < 0.001, by general estimating equation modeling, and accounting for age and within-subject, intereye correlations). Studying the relationship between ONHC abnormalities and alterations in validated structural and functional measures of the visual system may facilitate the ability to dissect and characterize the pathobiological mechanisms that contribute to tissue damage in MS, and may have utility to detect and monitor neuroprotective or restorative effects of novel therapies.

Efficacy of thiolated eudragit microspheres as an oral vaccine delivery system to induce mucosal immunity against enterotoxigenic Escherichia coli in mice.

PubMed

Lee, Won-Jung; Cha, Seungbin; Shin, Minkyoung; Jung, Myunghwan; Islam, Mohammad Ariful; Cho, Chong-su; Yoo, Han Sang

2012-05-01

A vaccine delivery system based on thiolated eudragit microsphere (TEMS) was studied in vivo for its ability to elicit mucosal immunity against enterotoxigenic Escherichia coli (ETEC). Groups of mice were orally immunized with F4 or F18 fimbriae of ETEC and F4 or F18 loaded in TEMS. Mice that were orally administered with F4 or F18 loaded TEMS showed higher antigen-specific IgG antibody responses in serum and antigen-specific IgA in saliva and feces than mice that were immunized with antigens only. In addition, oral vaccination of F4 or F18 loaded TEMS resulted in higher numbers of IgG and IgA antigen-specific antibody secreting cells in the spleen, lamina propria, and Peyer's patches of immunized mice than other groups. Moreover, TEMS administration loaded with F4 or F18 induced mixed Th1 and Th2 type responses based on similarly increased levels of IgG1 and IgG2a. These results suggest that F4 or F18 loaded TEMS may be a promising candidate for an oral vaccine delivery system to elicit systemic and mucosal immunity against ETEC. Copyright © 2012 Elsevier B.V. All rights reserved.

Positive concomitant test reactions to allergens in the standard patch test series.

PubMed

Landeck, Lilla; González, Ernesto; Baden, Lynn; Neumann, Konrad; Schalock, Peter

2010-05-01

Patch testing is performed to evaluate suspected allergic contact dermatitis. Common wisdom suggests that various allergens cross-react but only a few larger studies have published confirmations of this. The purpose of our study was to identify significant correlations between positive test reactions in a screening series. A total of 1235 patients undergoing patch testing to the Hermal standard series at the Massachusetts General Hospital, Contact Dermatitis Clinic between 1990 and 2006 were investigated. Two or more positive reactions were seen in 411 patients (33.3%). Sensitizations to eight pairs of allergens were found to have significant correlation (P

Dynamic Assessment of Elicited Imitation: A Case Analysis of an Advanced L2 English Speaker

ERIC Educational Resources Information Center

van Compernolle, Rémi A.; Zhang, Haomin

2014-01-01

The focus of this paper is on the design, administration, and scoring of a dynamically administered elicited imitation test of L2 English morphology. Drawing on Vygotskian sociocultural psychology, particularly the concepts of zone of proximal development and dynamic assessment, we argue that support provided during the elicited imitation test…

Making contact for contact dermatitis: a survey of the membership of the American Contact Dermatitis Society.

PubMed

Nezafati, Kaveh A; Carroll, Bryan; Storrs, Frances J; Cruz, Ponciano D

2013-01-01

The American Contact Dermatitis Society (ACDS) is the principal organization representing the subspecialty of contact dermatitis in the United States. The aim of this study was to characterize ACDS members with respect to demographic characteristics, patch-test practices, and sentiments regarding the Society and its journal Dermatitis. We conducted cross-sectional postal and online surveys of ACDS members. More than a third of ACDS members responded to the survey, 92% of whom practice dermatology, and most of whom are community practitioners. Responders manage patients with allergic and irritant dermatitis at a similar frequency. On average, they patch test 4 patients per week using 66 allergens per patient, which often include customized trays. Almost half of these practitioners learned patch testing from their residency programs. Most of the responders read and value the Society journal, value the Contact Allergen Management Program database, and attend society meetings. The ACDS is comprised overwhelmingly of dermatologists who are primarily community-based, young relative to the start of their practices, and use the Society's resources for continuing education.

Assessment of hypoallergenicity of ten skincare products.

PubMed

Brandt, Staci; Lio, Peter

2014-03-01

Sensitive skin is a common skin complaint frequently associated with skin diseases or adverse reactions to cosmetic products. Manufacturers have produced numerous products targeted for patients with sensitive skin and frequently label these products as being hypoallergenic. This term implies that the product may be less likely to cause an allergic reaction and be better suited for those with sensitive skin. However, there is no federal regulatory definition of this term and products may not have clinical support of their claim. Patch testing ingredients is frequently done to identify potential irritants; however, patch-testing product formulations may provide more realistic expectations about potential skin sensitivity and help support claims of hypoallergenicity. Ten skincare products were assessed for their sensitizing potential and hypoallergenicity in 14 repeat insult patch test clinical studies, involving over 2,000 subjects. In these studies, the products were deemed to be hypoallergenic if there was no evidence of sensitization or allergic reactions. The results from these trials demonstrated that all ten products were well tolerated, showed no sensitization or allergic reactions, and support claims of hypoallergenicity.

Burning mouth syndrome: the role of contact hypersensitivity.

PubMed

Marino, R; Capaccio, P; Pignataro, L; Spadari, F

2009-05-01

Burning mouth syndrome is a burning sensation or stinging disorder affecting the oral mucosa in the absence of any clinical signs or mucosal lesions. Some studies have suggested that burning mouth syndrome could be caused by the metals used in dental prostheses, as well as by acrylate monomers, additives and flavouring agents, although others have not found any aetiologic role for hypersensitivity to dental materials. To evaluate the extent and severity of adverse reactions to dental materials in a group of patients with burning mouth syndrome, and investigate the possible role of contact allergy in its pathogenesis. We prospectively studied 124 consecutive patients with burning mouth syndrome (108 males; mean age 57 years, range 41-83), all of whom underwent allergen patch testing between 2004 and 2007. Sixteen patients (13%) showed positive patch test reactions and were classified as having burning mouth syndrome type 3 or secondary burning mouth syndrome (Lamey's and Scala's classifications). Although we did not find any significant association between the patients and positive patch test reactions, it would be advisable to include hypersensitivity to dental components when evaluating patients experiencing intermittent oral burning without any clinical signs.

Planar biaxial testing of heart valve cusp replacement biomaterials: Experiments, theory and material constants.

PubMed

Labrosse, Michel R; Jafar, Reza; Ngu, Janet; Boodhwani, Munir

2016-11-01

Aortic valve (AV) repair has become an attractive option to correct aortic insufficiency. Yet, cusp reconstruction with various cusp replacement materials has been associated with greater long-term repair failures, and it is still unknown how such materials mechanically compare with native leaflets. We used planar biaxial testing to characterize six clinically relevant cusp replacement materials, along with native porcine AV leaflets, to ascertain which materials would be best suited for valve repair. We tested at least six samples of: 1) fresh autologous porcine pericardium (APP), 2) glutaraldehyde fixed porcine pericardium (GPP), 3) St Jude Medical pericardial patch (SJM), 4) CardioCel patch (CC), 5) PeriGuard (PG), 6) Supple PeriGuard (SPG) and 7) fresh porcine AV leaflets (PC). We introduced efficient displacement-controlled testing protocols and processing, as well as advanced convexity requirements on the strain energy functions used to describe the mechanical response of the materials under loading. The proposed experimental and data processing pipeline allowed for a robust in-plane characterization of all the materials tested, with constants determined for two Fung-like hyperelastic, anisotropic strain energy models. Overall, CC and SPG (respectively PG) patches ranked as the closest mechanical equivalents to young (respectively aged) AV leaflets. Because the native leaflets as well as CC, PG and SPG patches exhibit significant anisotropic behaviors, it is suggested that the fiber and cross-fiber directions of these replacement biomaterials be matched with those of the host AV leaflets. The long-term performance of cusp replacement materials would ideally be evaluated in large animal models for AV disease and cusp repair, and over several months or more. Given the unavailability and impracticality of such models, detailed information on stress-strain behavior, as studied herein, and investigations of durability and valve dynamics will be the best surrogates, as they have been for prosthetic valves. Overall, comparison with Fig. 3 suggests that CC and SPG (respectively PG) patches may be the closest mechanical equivalents to young (respectively aged) AV leaflets. Interestingly, the thicknesses of these materials are close to those reported for porcine and younger human AV leaflets, which may facilitate surgical implantation, by contrast to the thinner APP which has poor handling qualities. Because the native leaflets as well as CC, PG and SPG patches exhibit anisotropic behaviors, from a mechanistic perspective alone, it stands to reason that cardiac surgeons should seek to intraoperatively match the fiber and cross-fiber directions of these replacement biomaterials with those of the repaired AV leaflets. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Exploration of ethyl anthranilate-loaded monolithic matrix-type prophylactic polymeric patch.

PubMed

Islam, Johirul; Zaman, Kamaruz; Chakrabarti, Srijita; Bora, Nilutpal Sharma; Pathak, Manash Pratim; Mandal, Santa; Junejo, Julfikar Ali; Chattopadhyay, Pronobesh

2017-10-01

Compromised stability of pharmaceutical formulations loaded with volatiles is a serious problem associated with devices designed to deliver volatile compounds. The present study has been focused to evaluate the stability potential of matrix-type polymeric patches composed of volatile ethyl anthranilate for prophylaxis against vector-borne diseases. Ethyl anthranilate-loaded matrix-type polymeric patches were fabricated by solvent evaporation method on an impermeable backing membrane and attached to temporary release liners. Stability testing of the polymeric patches was performed as per the International Conference on Harmonization (ICH) guidelines for 6 months under accelerated conditions. In addition, the quantification of residual solvents was also performed as per the ICH guidelines. After conducting the stability studies for 6 months, the optimized patches showed the best possible results with respect to uniformity of drug content, physical appearance, and other analytical parameters. Furthermore, the amount of residual solvent was found well below the accepted limit. Thus, the present report outlined the analytical parameters to be evaluated to ensure the stability of a certain devices consisting of volatile compounds. Copyright © 2016. Published by Elsevier B.V.

Contact allergy to denture materials in the burning mouth syndrome.

PubMed

van Joost, T; van Ulsen, J; van Loon, L A

1988-02-01

Several factors may be responsible for stomatitis in general and the burning mouth syndrome in particular. The results of patch testing are reported in 4 patients with burning mouth symptoms thought to be due to sensitization to denture material. 2 patients reacted to substances in Luxene dentures, but the allergens were not identified. In a 3rd patient, sensitization was found to monomeric methyl methacrylate. The other patient gave positive patch tests to epoxy resin (and bisphenol A), probably present in glue used for repair of dental plates. To obtain a complete diagnosis in cases of suspected contact stomatitis due to allergens in dentures, a reliable standard test series is required.

24 and 48 h allergen exposure in patch testing. Comparative study with 11 common contact allergens and NiCl2.

PubMed

Kalimo, K; Lammintausta, K

1984-01-01

Patch test reactions to 11 common contact allergens were studied after 24 h and 48 h occlusion with Finn Chambers in 390 patients. Concordant allergic results were found in 96 cases (74%). In 22 patients (17%), the reaction was positive only after 48 h and in 11 cases (8.5%) only after 24 h exposure. Most of the discordant reactions were to nickel, cobalt, neomycin, formaldehyde and perfume mix. Irritant reactions were found in 55 cases, the majority occurring after 48 h occlusion. Nickel chloride tested in parallel with 48 h exposure lead to more positive allergic and toxic reactions than nickel sulphate.

Simple Test Functions in Meshless Local Petrov-Galerkin Methods

NASA Technical Reports Server (NTRS)

Raju, Ivatury S.

2016-01-01

Two meshless local Petrov-Galerkin (MLPG) methods based on two different trial functions but that use a simple linear test function were developed for beam and column problems. These methods used generalized moving least squares (GMLS) and radial basis (RB) interpolation functions as trial functions. These two methods were tested on various patch test problems. Both methods passed the patch tests successfully. Then the methods were applied to various beam vibration problems and problems involving Euler and Beck's columns. Both methods yielded accurate solutions for all problems studied. The simple linear test function offers considerable savings in computing efforts as the domain integrals involved in the weak form are avoided. The two methods based on this simple linear test function method produced accurate results for frequencies and buckling loads. Of the two methods studied, the method with radial basis trial functions is very attractive as the method is simple, accurate, and robust.

Foraging decisions in wild versus domestic Mus musculus: What does life in the lab select for?

PubMed

Troxell-Smith, Sandra M; Tutka, Michal J; Albergo, Jessica M; Balu, Deebika; Brown, Joel S; Leonard, John P

2016-01-01

What does domestication select for in terms of foraging and anti-predator behaviors? We applied principles of patch use and foraging theory to test foraging strategies and fear responses of three strains of Mus musculus: wild-caught, control laboratory, and genetically modified strains. Foraging choices were quantified using giving-up densities (GUDs) under three foraging scenarios: (1) patches varying in microhabitat (covered versus open), and initial resource density (low versus high); (2) daily variation in auditory cues (aerial predators and control calls); (3) patches with varying seed aggregations. Overall, both domestic strains harvested significantly more food than wild mice. Each strain revealed a significant preference for foraging under cover compared to the open, and predator calls had no detectable effects on foraging. Both domestic strains biased their harvest toward high quality patches; wild mice did not. In terms of exploiting favorable and avoiding unfavorable distributions of seeds within patches, the lab strain performed best, the wild strain worst, and the mutant strain in between. Our study provides support for hypothesis that domestic animals have more energy-efficient foraging strategies than their wild counterparts, but retain residual fear responses. Furthermore, patch-use studies can reveal the aptitudes and priorities of both domestic and wild animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Free nicotine patches plus proactive telephone peer support to help low-income women stop smoking.

PubMed

Solomon, L J; Scharoun, G M; Flynn, B S; Secker-Walker, R H; Sepinwall, D

2000-07-01

This study tested the impact of free nicotine patches plus proactive telephone peer support to help low-income women stop smoking. A total of 214 Medicaid-eligible women smokers of childbearing age were randomized to receive free nicotine patches through the mail or free nicotine patches through the mail plus the provision of proactive support by telephone from a woman ex-smoker for up to 3 months. Assessments were conducted by telephone at baseline, 10 days, and 3 and 6 months after enrollment. At the 3-month follow-up, significantly more women in the patch plus proactive telephone support condition were abstinent (42%) compared to the patch only condition (28%) (P = 0.03). Similarly, more women in the experimental condition were abstinent at both the 10-day and 3-month assessments (32 v 19%, P = 0.02). However, differences were not found at the 6-month follow-up, suggesting that the addition of proactive telephone peer support enhanced short-term, but not long-term cessation. This is the first study to demonstrate a beneficial effect for the addition of proactive telephone support as an adjunct to free nicotine replacement in a low-income population. Copyright 2000 American Health Foundation and Academic Press.

Depletion of deep marine food patches forces divers to give up early.

PubMed

Thums, Michele; Bradshaw, Corey J A; Sumner, Michael D; Horsburgh, Judy M; Hindell, Mark A

2013-01-01

Many optimal foraging models for diving animals examine strategies that maximize time spent in the foraging zone, assuming that prey acquisition increases linearly with search time. Other models have considered the effect of patch quality and predict a net energetic benefit if dives where no prey is encountered early in the dive are abandoned. For deep divers, however, the energetic benefit of giving up is reduced owing to the elevated energy costs associated with descending to physiologically hostile depths, so patch residence time should be invariant. Others consider an asymptotic gain function where the decision to leave a patch is driven by patch-depletion effects - the marginal value theorem. As predator behaviour is increasingly being used as an index of marine resource density and distribution, it is important to understand the nature of this gain function. We investigated the dive behaviour of the world's deepest-diving seal, the southern elephant seal Mirounga leonina, in response to patch quality. Testing these models has largely been limited to controlled experiments on captive animals. By integrating in situ measurements of the seal's relative lipid content obtained from drift rate data (a measure of foraging success) with area-restricted search behaviour identified from first-passage time analysis, we identified regions of high- and low-quality patches. Dive durations and bottom times were not invariant and did not increase in regions of high quality; rather, both were longer when patches were of relatively low quality. This is consistent with the predictions of the marginal value theorem and provides support for a nonlinear relationship between search time and prey acquisition. We also found higher descent and ascent rates in high-quality patches suggesting that seals minimized travel time to the foraging patch when quality was high; however, this was not achieved by increasing speed or dive angle. Relative body lipid content was an important predictor of dive behaviour. Seals did not schedule their diving to maximize time spent in the foraging zone in higher-quality patches, challenging the widely held view that maximizing time in the foraging zone translates to greater foraging success. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Frequency and trends of contact allergy to and iatrogenic contact dermatitis caused by topical drugs over a 25-year period.

PubMed

Gilissen, Liesbeth; Goossens, An

2016-11-01

Allergic contact dermatitis is the most common adverse reaction caused by topical drugs. To study the demographic characteristics and lesion locations of patients with iatrogenic dermatitis, and to analyse contact allergy to active principles and trends in frequencies over the years. Between 1990 and 2014, 14 911 patients were patch tested with the European baseline series. Patients with a presumed iatrogenic cause were often tested with a pharmaceutical series, and, if indicated, with photo-patch tests. Most were also tested with the topical products to which they had been exposed, along with their ingredients. Eight thousand three hundred and seventy-four (56%) patients tested positively, and 2600 (17.4%, 95%CI: 16.8-18.0%) of all patients suffered from iatrogenic contact dermatitis. The most important primary sites of dermatitis were the legs, face, and hands. The most common sensitizers included topical antibiotics, antiseptics, and corticosteroids. The most frequent baseline allergens in this subgroup were budesonide, neomycin, and benzocaine, although with a decreasing trend over the years. Many other allergens from different pharmacological classes were identified. With a prevalence of 17.4% of consecutive patients, iatrogenic contact dermatitis is a frequent diagnosis in patients attending a general patch test clinic, involving one-third of the patients with at least one positive reaction. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Identification of Lilial as a fragrance sensitizer in a perfume by bioassay-guided chemical fractionation and structure-activity relationships.

PubMed

Arnau, E G; Andersen, K E; Bruze, M; Frosch, P J; Johansen, J D; Menné, T; Rastogi, S C; White, I R; Lepoittevin, J P

2000-12-01

Fragrance materials are among the most common causes of allergic contact dermatitis. The aim of this study was to identify in a perfume fragrance allergens not included in the fragrance mix, by use of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships (SARs). The basis for the investigation was a 45-year-old woman allergic to her own perfume. She had a negative patch test to the fragrance mix and agreed to participate in the study. Chemical fractionation of the perfume concentrate was used for repeated patch testing and/or repeated open application test on the pre-sensitized patient. The chemical composition of the fractions giving a positive patch-test response and repeated open application test reactions was obtained by gas chromatography-mass spectrometry. From the compounds identified, those that contained a "structural alert" in their chemical structure, indicating an ability to modify skin proteins and thus behave as a skin sensitizer, were tested on the patient. The patient reacted positively to the synthetic fragrance p-t-butyl-alpha-methylhydrocinnamic aldehyde (Lilial), a widely used fragrance compound not present in the fragrance mix. The combination of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships seems to be a valuable tool for the investigation of contact allergy to fragrance materials.

Occupational contact dermatitis caused by aniline epoxy resins in the aircraft industry.

PubMed

Pesonen, Maria; Suuronen, Katri; Jolanki, Riitta; Aalto-Korte, Kristiina; Kuuliala, Outi; Henriks-Eckerman, Maj-Len; Valtanen, Ilona; Alanko, Kristiina

2015-08-01

Tetraglycidyl-4,4'-methylenedianiline (TGMDA) is an aniline epoxy resin used in, for example, resin systems of pre-impregnated composite materials (prepregs) of the aircraft industry. Allergic contact dermatitis caused by TGMDA in prepregs has been described previously. To report on 9 patients with occupational allergic contact dermatitis caused by TGMDA in epoxy glues used in helicopter assembly. The patients were examined with patch testing at the Finnish Institute of Occupational Health in 2004-2009. The first patient was diagnosed by testing both components of two epoxy glues from the workplace, and was also tested with glue ingredients, including TGMDA. The following patients were tested with the glues and TGMDA. The resin parts of the glues were analysed for their epoxy compounds, including TGMDA. All of the patients had a patch test reaction to one or both of the resin parts of the TGMDA-containing glues. Eight of them had a strong allergic reaction to TGMDA, and one had a doubtful reaction to TGMDA. Two of the patients also had an allergic reaction to triglycidyl-p-aminophenol (TGPAP), another aniline epoxy resin, which was not present in the TGMDA-containing glues. In aircraft industry workers with suspected occupational dermatitis, aniline epoxy resins should be considered and patch tested as possible contact allergens. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Patch testing with hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) - a multicentre study of the Swedish Contact Dermatitis Research Group.

PubMed

Engfeldt, Malin; Hagvall, Lina; Isaksson, Marléne; Matura, Mihály; Mowitz, Martin; Ryberg, Kristina; Stenberg, Berndt; Svedman, Cecilia; Bruze, Magnus

2017-01-01

In 2014, the fragrance hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) was excluded from the Swedish baseline series. To study (i) whether fragrance mix (FM) II with 5% HICC detects more positive reactions than usual FM II with 2.5% HICC, and (ii) the reproducibility of patch testing with HICC. Two thousand one hundred and eighteen dermatitis patients at five Swedish dermatology departments were consecutively tested with FM II 14% pet., FM II 16.5% pet., and duplicate preparations of HICC 5% pet. Of the patients, 3.2% reacted to FM II 14%, and 1.5% reacted to HICC. Separate testing with HICC detected 0.3% reactions without concomitant reactivity to FM II. FM II with 5% HICC did not give rise to more irritant reactions or signs of active sensitization than FM II with 2.5% HICC. Patch testing with duplicate applications of HICC increased the overall prevalence of HICC contact allergy to 1.9%. FM II with 5% HICC does not detect more positive reactions than FM II with 2.5% HICC. Separate testing with HICC does not detect a sufficient proportion of patients who react only to HICC, without concomitant reactions to FM II, to warrant its inclusion in a baseline series. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Occupational Airborne Contact Dermatitis From Proton Pump Inhibitors.

PubMed

DeKoven, Joel G; Yu, Ashley M

2015-01-01

Few published reports have described occupational contact dermatitis from proton pump inhibitor (PPI) exposure in the literature. We present an additional case of a 58-year-old male pharmaceutical worker with an occupational airborne allergic contact dermatitis to PPIs confirmed by patch testing. This is a novel report of workplace exposure to dexlansoprazole and esomeprazole PPIs with resultant clinical contact allergy and relevant positive patch test results to these 2 agents. A literature review of all previously reported cases of occupational contact dermatitis to PPI is summarized. The case also emphasizes the importance of even minute exposures when considering workplace accommodation.

Allergic contact dermatitis to indium in jewellery: diagnosis made possible through the use of the Contact Allergen Bank Australia.

PubMed

Gamboni, Sarah E; Simmons, Ivan; Palmer, Amanda; Nixon, Rosemary L

2013-05-01

We report a case of a 39-year-old woman from Adelaide who developed allergic contact dermatitis to the rare allergen indium in her ring. The allergen was sourced for patch testing using the Contact Allergen Bank Australia (CABA), based at the Skin and Cancer Foundation in Melbourne, and posted to Adelaide. This case illustrates the usefulness of CABA in facilitating patch testing throughout Australia, especially when rare allergens are involved. © 2013 The Authors. Australasian Journal of Dermatology © 2013 The Australasian College of Dermatologists.

Electrophysiological properties of myocytes isolated from the mouse atrioventricular node: L-type ICa, IKr, If, and Na-Ca exchange

PubMed Central

Choisy, Stéphanie C; Cheng, Hongwei; Orchard, Clive H; James, Andrew F; Hancox, Jules C

2015-01-01

The atrioventricular node (AVN) is a key component of the cardiac pacemaker-conduction system. This study investigated the electrophysiology of cells isolated from the AVN region of adult mouse hearts, and compared murine ionic current magnitude with that of cells from the more extensively studied rabbit AVN. Whole-cell patch-clamp recordings of ionic currents, and perforated-patch recordings of action potentials (APs), were made at 35–37°C. Hyperpolarizing voltage commands from −40 mV elicited a Ba2+-sensitive inward rectifier current that was small at diastolic potentials. Some cells (Type 1; 33.4 ± 2.2 pF; n = 19) lacked the pacemaker current, If, whilst others (Type 2; 34.2 ± 1.5 pF; n = 21) exhibited a clear If, which was larger than in rabbit AVN cells. On depolarization from −40 mV L-type Ca2+ current, ICa,L, was elicited with a half maximal activation voltage (V0.5) of −7.6 ± 1.2 mV (n = 24). ICa,L density was smaller than in rabbit AVN cells. Rapid delayed rectifier (IKr) tail currents sensitive to E-4031 (5 μmol/L) were observed on repolarization to −40 mV, with an activation V0.5 of −10.7 ± 4.7 mV (n = 8). The IKr magnitude was similar in mouse and rabbit AVN. Under Na-Ca exchange selective conditions, mouse AVN cells exhibited 5 mmol/L Ni-sensitive exchange current that was inwardly directed negative to the holding potential (−40 mV). Spontaneous APs (5.2 ± 0.5 sec−1; n = 6) exhibited an upstroke velocity of 37.7 ± 16.2 V/s and ceased following inhibition of sarcoplasmic reticulum Ca2+ release by 1 μmol/L ryanodine, implicating intracellular Ca2+ cycling in murine AVN cell electrogenesis. PMID:26607172

Development of Modal Test Techniques for Validation of a Solar Sail Design

NASA Technical Reports Server (NTRS)

Gaspar, James L.; Mann, Troy; Behun, Vaughn; Wilkie, W. Keats; Pappa, Richard

2004-01-01

This paper focuses on the development of modal test techniques for validation of a solar sail gossamer space structure design. The major focus is on validating and comparing the capabilities of various excitation techniques for modal testing solar sail components. One triangular shaped quadrant of a solar sail membrane was tested in a 1 Torr vacuum environment using various excitation techniques including, magnetic excitation, and surface-bonded piezoelectric patch actuators. Results from modal tests performed on the sail using piezoelectric patches at different positions are discussed. The excitation methods were evaluated for their applicability to in-vacuum ground testing and to the development of on orbit flight test techniques. The solar sail membrane was tested in the horizontal configuration at various tension levels to assess the variation in frequency with tension in a vacuum environment. A segment of a solar sail mast prototype was also tested in ambient atmospheric conditions using various excitation techniques, and these methods are also assessed for their ground test capabilities and on-orbit flight testing.

Predicting nucleic acid binding interfaces from structural models of proteins.

PubMed

Dror, Iris; Shazman, Shula; Mukherjee, Srayanta; Zhang, Yang; Glaser, Fabian; Mandel-Gutfreund, Yael

2012-02-01

The function of DNA- and RNA-binding proteins can be inferred from the characterization and accurate prediction of their binding interfaces. However, the main pitfall of various structure-based methods for predicting nucleic acid binding function is that they are all limited to a relatively small number of proteins for which high-resolution three-dimensional structures are available. In this study, we developed a pipeline for extracting functional electrostatic patches from surfaces of protein structural models, obtained using the I-TASSER protein structure predictor. The largest positive patches are extracted from the protein surface using the patchfinder algorithm. We show that functional electrostatic patches extracted from an ensemble of structural models highly overlap the patches extracted from high-resolution structures. Furthermore, by testing our pipeline on a set of 55 known nucleic acid binding proteins for which I-TASSER produces high-quality models, we show that the method accurately identifies the nucleic acids binding interface on structural models of proteins. Employing a combined patch approach we show that patches extracted from an ensemble of models better predicts the real nucleic acid binding interfaces compared with patches extracted from independent models. Overall, these results suggest that combining information from a collection of low-resolution structural models could be a valuable approach for functional annotation. We suggest that our method will be further applicable for predicting other functional surfaces of proteins with unknown structure. Copyright © 2011 Wiley Periodicals, Inc.

An Active Patch Model for Real World Texture and Appearance Classification

PubMed Central

Mao, Junhua; Zhu, Jun; Yuille, Alan L.

2014-01-01

This paper addresses the task of natural texture and appearance classification. Our goal is to develop a simple and intuitive method that performs at state of the art on datasets ranging from homogeneous texture (e.g., material texture), to less homogeneous texture (e.g., the fur of animals), and to inhomogeneous texture (the appearance patterns of vehicles). Our method uses a bag-of-words model where the features are based on a dictionary of active patches. Active patches are raw intensity patches which can undergo spatial transformations (e.g., rotation and scaling) and adjust themselves to best match the image regions. The dictionary of active patches is required to be compact and representative, in the sense that we can use it to approximately reconstruct the images that we want to classify. We propose a probabilistic model to quantify the quality of image reconstruction and design a greedy learning algorithm to obtain the dictionary. We classify images using the occurrence frequency of the active patches. Feature extraction is fast (about 100 ms per image) using the GPU. The experimental results show that our method improves the state of the art on a challenging material texture benchmark dataset (KTH-TIPS2). To test our method on less homogeneous or inhomogeneous images, we construct two new datasets consisting of appearance image patches of animals and vehicles cropped from the PASCAL VOC dataset. Our method outperforms competing methods on these datasets. PMID:25531013

Patching vs Atropine to Treat Amblyopia in Children Aged 7 to 12 Years: A Randomized Trial

PubMed Central

2008-01-01

Objective To compare patching with atropine eye drops in the treatment of moderate amblyopia (20/40 -20/100) in children age 7 to 12 years. Methods In a randomized multi-center clinical trial, 193 children with amblyopia were randomized to weekend atropine or patching 2 hours per day of the sound eye. Main Outcome Measure Masked assessment of amblyopic eye visual acuity using the EETDRS testing protocol at 17 weeks. Results At 17 weeks, visual acuity had improved from baseline by an average of 7.6 letters in the atropine group and 8.6 letters in the patching group. The mean difference (patching minus atropine) between groups adjusted for baseline acuity was 1.2 letters (ends of complementary 1-sided 95% confidence intervals for noninferiority = -0.7 and +3.1 letters). Based on the confidence intervals this difference met the pre-specified definition for equivalence (ends of confidence intervals <5 letters). Amblyopic eye visual acuity was 20/25 or better in 15 subjects (17%) in the atropine group and 20 subjects (24%) in the patching group (difference = 7%, 95% confidence interval = -3% to 17%). Conclusions Treatment with atropine or patching leads to similar degrees of improvement in 7 to 12 year old children with moderate amblyopia. About 1 in 5 achieves 20/25 or better visual acuity in the amblyopic eye. Application to Clinical Practice Treatment of older children with unilateral amblyopia. PMID:19064841

Testing Moral Foundation Theory: Are Specific Moral Emotions Elicited by Specific Moral Transgressions?

ERIC Educational Resources Information Center

Landmann, Helen; Hess, Ursula

2018-01-01

Moral foundation theory posits that specific moral transgressions elicit specific moral emotions. To test this claim, participants (N = 195) were asked to rate their emotions in response to moral violation vignettes. We found that compassion and disgust were associated with care and purity respectively as predicted by moral foundation theory.…

Reexamining Elicited Imitation as a Measure of Implicit Grammatical Knowledge and Beyond…?

ERIC Educational Resources Information Center

Sarandi, Hedayat

2015-01-01

This study examines elicited imitation (EI) both as a measure of implicit grammatical knowledge and more global semantic and syntactic knowledge. It also examines whether length affects the difficulty of EI tests when they contain both grammatical and ungrammatical items. Fifty language learners took an EI test and an oral narrative task. The data…

Using Automatic Speech Recognition Technology with Elicited Oral Response Testing

ERIC Educational Resources Information Center

Cox, Troy L.; Davies, Randall S.

2012-01-01

This study examined the use of automatic speech recognition (ASR) scored elicited oral response (EOR) tests to assess the speaking ability of English language learners. It also examined the relationship between ASR-scored EOR and other language proficiency measures and the ability of the ASR to rate speakers without bias to gender or native…

Comparison of elicitation potential of chloroatranol and atranol--2 allergens in oak moss absolute.

PubMed

Johansen, Jeanne D; Bernard, Guillaume; Giménez-Arnau, Elena; Lepoittevin, Jean-Pierre; Bruze, Magnus; Andersen, Klaus E

2006-04-01

Chloroatranol and atranol are degradation products of chloroatranorin and atranorin, respectively, and have recently been identified as important contact allergens in the natural fragrance extract, oak moss absolute. Oak moss absolute is widely used in perfumery and is the cause of many cases of fragrance allergic contact dermatitis. Chloroatranol elicits reactions at very low levels of exposure. In oak moss absolute, chloroatranol and atranol are present together and both may contribute to the allergenicity and eliciting capacity of the natural extract. In this study, 10 eczema patients with known sensitization to chloroatranol and oak moss absolute were tested simultaneously to a serial dilution of chloroatranol and atranol in ethanol, in equimolar concentrations (0.0034-1072 microM). Dose-response curves were estimated and analysed by logistic regression. The estimated difference in elicitation potency of chloroatranol relative to atranol based on testing with equimolar concentrations was 217% (95% confidence interval 116-409%). Both substances elicited reactions at very low levels of exposure. It is concluded that the differences in elicitation capacity between the 2 substances are counterbalanced by exposure being greater to atranol than to chloroatranol and that both substances contribute to the clinical problems seen in oak moss absolute-sensitized individuals.

Lessons from atopy patch testing in atopic dermatitis.

PubMed

Kerschenlohr, Karin; Darsow, Ulf; Burgdorf, Walter H C; Ring, Johannes; Wollenberg, Andreas

2004-07-01

The exposure of atopic eczema (AE) patients to their relevant protein allergens (eg, from house dust mite, cat dander, grass pollen, or food allergens) can trigger an exacerbation or maintain the disease. Diagnostic procedures are needed to specify allergen avoidance recommendations for the individual patient. Skin prick tests and specific serum IgE tests might be helpful in pointing out potential trigger factors, but relevance needs to be confirmed (eg, with food provocation tests). The atopy patch test (APT) involves the epicutaneous application of intact protein allergens in a diagnostic patch test setting with an evaluation of the induced eczematous skin lesions after 24 to 72 hours. The APT targets the cellular component of AE and helps round out the AE test spectrum. As a number of apparently minor test modifications greatly influence the sensitivity, specificity, and reproducibility of the APT, the European Task Force on Atopic Dermatitis (ETFAD) has developed a standardized APT technique. It consists of purified allergen preparations in petrolatum, applied in 12-mm diameter Finn chambers mounted on Scanpor tape to non-irritated, non-abraded, or tape-stripped skin of the upper back. The APT is read at 48 and 72 hours according to the test criteria and reading key of the ETFAD for appearance of erythema, and number and distribution pattern of the papules. In contrast with skin prick tests, the APT might even detect a relevant sensitization in the absence of specific IgE. Many studies have been undertaken to objectify the sensitivity and specificity of the APT to show its diagnostic use in clinical practice.

The fragrance mix and its constituents: a 14-year material.

PubMed

Johansen, J D; Menné, T

1995-01-01

Results from 14 years of patch testing with the fragrance mix and its constituents are reviewed. From 1979-1992, 8215 consecutive patients were patch tested with the fragrance mix and 449 (5.5%) had a positive reaction. An increase in the frequency of reactions to fragrance mix was seen from the first 5-year period to the last. Only 54.4% of the patients tested in the last 5-year period with the individual constituents of the mix had at least 1 positive reaction. The results of testing with the constituents are the basis for a discussion of methodological problems. A significant decrease in the frequency of reaction to cinnamic aldehyde was registered, at the same time as the test concentration was reduced from 2% to 1% pet. However, no significant variations in the frequency of reactions to oak moss were seen, notwithstanding a similar reduction in test concentration.

Fabrication and characterization of chitosan nanoparticles and collagen-loaded polyurethane nanocomposite membrane coated with heparin for atrial septal defect (ASD) closure.

PubMed

Kaiser, Eva; Jaganathan, Saravana Kumar; Supriyanto, Eko; Ayyar, Manikandan

2017-07-01

Atrial septal defect (ASD) constitutes 30-40% of all congenital heart diseases in adults. The most common complications in the treatment of ASD are embolization of the device and thrombosis formation. In this research, an occluding patch was developed for ASD treatment using a well-known textile technology called electrospinning. For the first time, a cardiovascular occluding patch was fabricated using medical grade polyurethane (PU) loaded with bioactive agents namely chitosan nanoparticles (Cn) and collagen (Co) which is then coated with heparin (Hp). Fourier transform infrared spectrum showed characteristic vibrations of several active constituents and changes in the absorbance due to the inclusion of active ingredients in the patch. The contact angle analysis demonstrated no significant decrease in contact angle compared to the control and the composite patches. The structure of the electrospun nanocomposite (PUCnCoHp) was examined through scanning electron microscopy. A decrease in nanofiber diameter between control PU and PUCnCoHp nanocomposite was observed. Water uptake was found to be decreased for the PUCnCoHp nanocomposite against the control. The hemocompatibility properties of the PUCnCoHp ASD occluding patch was inferred through in vitro hemocompatibility tests like activated partial thromboplastin time (APTT), prothrombin time (PT) and hemolysis assay. It was found that the PT and APTT time was significantly prolonged for the fabricated PUCnCoHp ASD occluding patch compared to the control. Likewise, the hemolysis percentage was also decreased for the PUCnCoHp ASD patch against the control. In conclusion, the developed PUCnCoHp patch demonstrates potential properties to be used for ASD occlusion.

Histological and molecular-biological analyses of poly(3-hydroxybutyrate) (PHB) patches for enhancement of bone regeneration.

PubMed

Gredes, Tomasz; Gedrange, Tomasz; Hinüber, Claudia; Gelinsky, Michael; Kunert-Keil, Christiane

2015-05-01

Tissue engineered cell-seeded constructs with poly(3)hydroxybutyrate (PHB) induced ectopic bone formation after implantation into the back muscle of rats. The objective of our in vivo study was to evaluate the osteogenic potential of pure PHB patches in surgically created cranial defects. For this, PHB patches were analyzed after implantation in surgically created defects on the cranium of adult male rats. After healing periods of 4, 8 and 12 weeks, the bone tissue specimens containing PHB patches were processed and analyzed histologically as well as molecular-biologically. After 4 weeks, the PHB patches were completely embedded in connective tissue. Eight weeks after PHB insertion, bone regeneration proceeding from bearing bone was found in 50% of all treated animals, whereas all PHB treated cavities showed both bone formation and embedding of the patches in bone 12 weeks after surgery. Furthermore, all slices showed pronounced development of blood vessels. Histomorphometric analysis presented a regenerated bone mean value between 46.4 ± 16.1% and 54.2 ± 19.3% after 4-12 weeks of healing. Caveolin-1 staining in capillary-like structures showed a 1.16-1.38 fold increased expression in PHB treated defects compared to controls. Real-time RT-PCR analyses showed significantly lower expressions of Alpl, Col1a1 and VEGFA in cranium defects after treatment with PHB patches compared to untreated bony defects of the same cranium. Within the limits of the presented animal investigation, it could conclude that the tested PHB patches featured a good biocompatibility and an osteoconductive character. Copyright © 2014 Elsevier GmbH. All rights reserved.

In vitro fabrication of a tissue engineered human cardiovascular patch for future use in cardiovascular surgery.

PubMed

Yang, Chao; Sodian, Ralf; Fu, Ping; Lüders, Cora; Lemke, Thees; Du, Jing; Hübler, Michael; Weng, Yuguo; Meyer, Rudolf; Hetzer, Roland

2006-01-01

One approach to tissue engineering has been the development of in vitro conditions for the fabrication of functional cardiovascular structures intended for implantation. In this experiment, we developed a pulsatile flow system that provides biochemical and biomechanical signals in order to regulate autologous, human patch-tissue development in vitro. We constructed a biodegradable patch scaffold from porous poly-4-hydroxy-butyrate (P4HB; pore size 80 to 150 microm). The scaffold was seeded with pediatric aortic cells. The cell-seeded patch constructs were placed in a self-developed bioreactor for 7 days to observe potential tissue formation under dynamic cell culture conditions. As a control, cell-seeded scaffolds were not conditioned in the bioreactor system. After maturation in vitro, the analysis of the tissue engineered constructs included biochemical, biomechanical, morphologic, and immunohistochemical examination. Macroscopically, all tissue engineered constructs were covered by cells. After conditioning in the bioreactor, the cells were mostly viable, had grown into the pores, and had formed tissue on the patch construct. Electron microscopy showed confluent smooth surfaces. Additionally, we demonstrated the capacity to generate collagen and elastin under in vitro pulsatile flow conditions in biochemical examination. Biomechanical testing showed mechanical properties of the tissue engineered human patch tissue without any statistical differences in strength or resistance to stretch between the static controls and the conditioned patches. Immunohistochemical examination stained positive for alpha smooth muscle actin, collagen type I, and fibronectin. There was minor tissue formation in the nonconditioned control samples. Porous P4HB may be used to fabricate a biodegradable patch scaffold. Human vascular cells attached themselves to the polymeric scaffold, and extracellular matrix formation was induced under controlled biomechanical and biodynamic stimuli in a self-developed pulsatile bioreactor system.

Comprehensive study of the intestinal stage of listeriosis in a rat ligated ileal loop system.

PubMed

Pron, B; Boumaila, C; Jaubert, F; Sarnacki, S; Monnet, J P; Berche, P; Gaillard, J L

1998-02-01

The intestinal stage of listeriosis was studied in a rat ligated ileal loop system. Listeria monocytogenes translocated to deep organs with similar efficiencies after inoculation of loops with or without Peyer's patches. Bacterial seeding of deep organs was demonstrated as early as 15 min after inoculation. It was dose dependent and nonspecific, as the delta inlAB, the delta hly, and the delta actA L. monocytogenes mutants and the nonpathogenic species, Listeria innocua, translocated similarly to wild-type L. monocytogenes strains. The levels of uptake of listeriae by Peyer's patches and villous intestine were similar and low, 50 to 250 CFU per cm2 of tissue. No listeria cells crossing the epithelial sheet of Peyer's patches and villous intestine were observed by transmission electron microscopy. The lack of significant interaction of listeriae and the follicle-associated epithelium of Peyer's patches was confirmed by scanning electron microscopy. The follicular tissue of Peyer's patches was a preferential site of Listeria replication. With all doses tested, the rate of bacterial growth was 10 to 20 times higher in Peyer's patches than in villous intestine. At early stages of Peyer's patch infection, listeriae were observed inside mononuclear cells of the dome area. Listeriae then disseminated throughout the follicular tissue except for the germinal center. The virulence determinants hly and, to a lesser extent, actA, but not inlAB, were required for the completion of this process. This study suggests that Peyer's patches are preferential sites for replication rather than for entry of L. monocytogenes, due to the presence of highly permissive mononuclear cells whose nature remains to be defined.

Comprehensive Study of the Intestinal Stage of Listeriosis in a Rat Ligated Ileal Loop System

PubMed Central

Pron, Benedicte; Boumaila, Claire; Jaubert, Francis; Sarnacki, Sabine; Monnet, Jean-Paul; Berche, Patrick; Gaillard, Jean-Louis

1998-01-01

The intestinal stage of listeriosis was studied in a rat ligated ileal loop system. Listeria monocytogenes translocated to deep organs with similar efficiencies after inoculation of loops with or without Peyer’s patches. Bacterial seeding of deep organs was demonstrated as early as 15 min after inoculation. It was dose dependent and nonspecific, as the ΔinlAB, the Δhly, and the ΔactA L. monocytogenes mutants and the nonpathogenic species, Listeria innocua, translocated similarly to wild-type L. monocytogenes strains. The levels of uptake of listeriae by Peyer’s patches and villous intestine were similar and low, 50 to 250 CFU per cm2 of tissue. No listeria cells crossing the epithelial sheet of Peyer’s patches and villous intestine were observed by transmission electron microscopy. The lack of significant interaction of listeriae and the follicle-associated epithelium of Peyer’s patches was confirmed by scanning electron microscopy. The follicular tissue of Peyer’s patches was a preferential site of Listeria replication. With all doses tested, the rate of bacterial growth was 10 to 20 times higher in Peyer’s patches than in villous intestine. At early stages of Peyer’s patch infection, listeriae were observed inside mononuclear cells of the dome area. Listeriae then disseminated throughout the follicular tissue except for the germinal center. The virulence determinants hly and, to a lesser extent, actA, but not inlAB, were required for the completion of this process. This study suggests that Peyer’s patches are preferential sites for replication rather than for entry of L. monocytogenes, due to the presence of highly permissive mononuclear cells whose nature remains to be defined. PMID:9453636

The Influence of Social Support on Smoking Cessation Treatment Adherence Among HIV+ Smokers.

PubMed

de Dios, Marcel A; Stanton, Cassandra A; Cano, Miguel Ángel; Lloyd-Richardson, Elizabeth; Niaura, Raymond

2016-05-01

The high prevalence of smoking among people living with HIV is a significant problem. Nonadherence to smoking cessation pharmacotherapy is a barrier for successfully quitting. The current study investigated the extent to which social support variables impact adherence and cessation. Participants were 444 HIV+ smokers who provided data on nicotine patch adherence, social support, and smoking. We conducted a path analysis to estimate (1) the effects of six social support indicators at baseline on nicotine patch adherence; (2) the effect of patch adherence on 7-day point prevalence smoking at 6-month follow-up; and (3) the indirect effects of social support indicators on 7-day point prevalence smoking at 6-month follow-up via patch adherence. The tested model demonstrated good fit as indicated by the comparative fit index, root mean square error of approximation, and weighted root mean square residual (0.94, 0.02, and 0.51, respectively). Path analysis results indicated greater social support network contact was associated with higher levels of nicotine patch adherence (β = .13, P = .02), greater patch adherence was associated with a lower probability of 7-day point prevalence smoking at 6-month follow-up (β = -.47, P < .001) and greater social support network contact (β = -.06, P = .03) had a significant indirect effect on 7-day point prevalence smoking at 6-month follow-up via patch adherence. Findings have implications for smoking cessation interventions that seek to capitalize on the beneficial effects of social support. Such efforts should account for the role that frequency of contact may have on nicotine patch use and other treatment-related mechanisms. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Spin Glass Patch Planting

NASA Technical Reports Server (NTRS)

Wang, Wenlong; Mandra, Salvatore; Katzgraber, Helmut G.

2016-01-01

In this paper, we propose a patch planting method for creating arbitrarily large spin glass instances with known ground states. The scaling of the computational complexity of these instances with various block numbers and sizes is investigated and compared with random instances using population annealing Monte Carlo and the quantum annealing DW2X machine. The method can be useful for benchmarking tests for future generation quantum annealing machines, classical and quantum mechanical optimization algorithms.

Influence of prey dispersion on territory and group size of African lions: a test of the resource dispersion hypothesis.

PubMed

Valeix, Marion; Loveridge, Andrew J; MacDonald, David W

2012-11-01

Empirical tests of the resource dispersion hypothesis (RDH), a theory to explain group living based on resource heterogeneity, have been complicated by the fact that resource patch dispersion and richness have proved difficult to define and measure in natural systems. Here, we studied the ecology of African lions Panthera leo in Hwange National Park, Zimbabwe, where waterholes are prey hotspots, and where dispersion of water sources and abundance of prey at these water sources are quantifiable. We combined a 10-year data set from GPS-collared lions for which information of group composition was available concurrently with data for herbivore abundance at waterholes. The distance between two neighboring waterholes was a strong determinant of lion home range size, which provides strong support for the RDH prediction that territory size increases as resource patches are more dispersed in the landscape. The mean number of herbivore herds using a waterhole, a good proxy of patch richness, determined the maximum lion group biomass an area can support. This finding suggests that patch richness sets a maximum ceiling on lion group size. This study demonstrates that landscape ecology is a major driver of ranging behavior and suggests that aspects of resource dispersion limit group sizes.

Social learning strategies and predation risk: minnows copy only when using private information would be costly

PubMed Central

Webster, M.M; Laland, K.N

2008-01-01

Animals can acquire information from the environment privately, by sampling it directly, or socially, through learning from others. Generally, private information is more accurate, but expensive to acquire, while social information is cheaper but less reliable. Accordingly, the ‘costly information hypothesis’ predicts that individuals will use private information when the costs associated with doing so are low, but that they should increasingly use social information as the costs of using private information rise. While consistent with considerable data, this theory has yet to be directly tested in a satisfactory manner. We tested this hypothesis by giving minnows (Phoxinus phoxinus) a choice between socially demonstrated and non-demonstrated prey patches under conditions of low, indirect and high simulated predation risk. Subjects had no experience (experiment 1) or prior private information that conflicted with the social information provided by the demonstrators (experiment 2). In both experiments, subjects spent more time in the demonstrated patch than in the non-demonstrated patch, and in experiment 1 made fewer switches between patches, when risk was high compared with when it was low. These findings are consistent with the predictions of the costly information hypothesis, and imply that minnows adopt a ‘copy-when-asocial-learning-is-costly’ learning strategy. PMID:18755676