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Test Substances (test + substance)
Selected AbstractsP72 Pigmented patch-test substance and laser Doppler perfusion imagingCONTACT DERMATITIS, Issue 3 2004Bolli Bjarnason Objective:, To investigate if pigment of a dark patch-test substance may affect assessment of perfusion with the laser Doppler imaging technique. Materials:, 13 subjects who previously patch-tested positive with 25% balsam of Peru in petrolatum were re-tested with the same test substance and petrolatum controls applied directly by transparent foils and with much weaker and less pigmented serial doses tested with polyester squares. Readings of perfusion were performed through the test substances and the transparent foils at time intervals up to 4 days while tests were applied and for 5 days following detachment of tests. The instrument set-up of the LDPI was the same as we have suggested for non-pigmented patch-test substances tested on white skin. Results:, Results show that pigment remnants following detachment of the dark pigmented and pasty test substance containing the petrolatum vehicle were prone to affect perfusion assessments by masking detection of perfusion of parts of test sites. A real masking effect is supported by a similar effect with readings of the same tests while they were applied and by no such observable effect with the petrolatum controls or the non-pasty and much less pigmented squares. Conclusion:, The results show that pigment of patch-test substances may affect perfusion assessments with the instrument set-up suggested for non-pigmented substances. [source] Effect of dark test-substance pigmentation on skin perfusion assessments and effect of test technique on balsam of Peru patch-test resultsCONTACT DERMATITIS, Issue 6 2000Bolli Bjarnason 13 balsam of Peru (Myroxylon Pereirae) patch-test-positive subjects are re-tested with 25% balsam of Peru in petrolatum and with serial doses printed on polyester squares. All substances are applied with tape strips for 3, 6, 24 (1 day [D]), 48 (2D), 72 (3D) and 96 h (4D) on each subject and for 96 h (4D) with plastic foils. Tests are followed visually and with perfusion assessments from 3 h to 9 days. Results show that pigment remnants following detachment of patches affect perfusion assessments. Such effect due to pigment is supported by readings of patch tests through the petrolatum test substance while applied with transparent foils. For most reactions, good agreement is observed between the assessment techniques when peak assessment values of reactions are compared. There is inter-individual variation in perfusion with identical tests. With the petrolatum test substance, increased visible reactivity was observed when the application time was extended up to 24 h (1D), while extension of application time increased perfusion in most cases except for an extension from 24 (2D) to 48 h (4D) where decreased perfusion resulted in most cases. Dose and application time did not affect the timing of highest reactivity of reactions in most cases. [source] Assessment of balsam of Peru patch testsCONTACT DERMATITIS, Issue 6 2000Bolli Bjarnason To find an ideal test technique for as low a dose of balsam of Peru (Myroxylon Pereirae) as possible, subjects testing positive to balsam of Peru are re-tested with a 25% concentration of balsam of Peru in petrolatum. Applications are with Finn Chambers® for 6 different application times, and directly by foils for 96 h (4 days (D)). The goals are to confirm which subjects are positive and which are not, and, using that information, to see if it is possible to distinguish between these 2 groups, tested concomitantly at much lower serial dose levels, in terms of perfusion or by visual assessments. 5 different serial doses are applied with strips for 3,96 h (4D) and with foils for 96 h (4D). The Finn Chamber® tests allow a distinction between visually positive and negative subjects supported by perfusion assessments. With the foils, a 24× lower serial dose level than with the 25% test substance is sufficient to distinguish between positive and negative subjects in terms of perfusion values. This approach requires readings up to 9 days. With this test, the visual approach yields only 3 of 10 positive subjects. This study demonstrates that a lower test dose is possible with perfusion assessments compared to visual ones. [source] Persistence and degradation of maize-expressed vaccine protein, Escherichia coli heat-labile enterotoxin subunit B, in soil and water,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2008Hirofumi Kosaki Abstract Transgenic plants represent an innovative platform for the cost-effective large-scale production of various pharmaceutical proteins. The eventual open-field production of plant-made pharmaceuticals (PMPs) requires risk assessment to determine the potential for harm to the surrounding ecosystem. In the present study, the environmental persistence of a transgenic maize-expressed antigen, Escherichia coli heat-labile enterotoxin subunit B (LTB), was studied under laboratory conditions. To semiquantitatively monitor the persistence of LTB in soil, extraction with a high-salt, high-pH extraction buffer was optimized using the closely homologous Vibrio cholerae enterotoxin subunit B (CTB) as a test substance. The time to dissipation of 50% (DT50) of the extractable fraction of maize-expressed LTB was 4 to 15 d in pond water and 35 to 90 d in soils. Both extraction efficacy and persistence were strongly affected by the matrix type and incubation conditions. In contrast with maize-expressed LTB, the DT50 for bacterially produced LTB and CTB was less than 4 d both in pond water and soil. Although maize-expressed LTB was more stable than bacterially produced analogue, its dissipation was governed by an initial lag, which could be attributed to release from the plant material, followed by rapid decline. [source] Soil and plant diet exposure routes and toxicokinetics of lindane in a terrestrial isopodENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2000José Paulo Sousa Abstract In most studies dealing with effects of toxic substances in saprotrophic isopods, animals are exposed to the test substance through contaminated food. Because these animals can be in a close contact with the soil surface, the substrate, as an exposure pathway, should not be neglected. Here the authors analyze the toxicokinetic behavior of lindane (,-hexachlorocyclohexane [,-HCH]) in the isopod species Porcellionides pruinosus, comparing two exposure routes: food and two soil types (artificial Organisation for Economic Cooperation and Development [OECD] soil and a natural agricultural soil). In the feeding experiment, a strong decrease of ,-HCH concentration over time was observed on the food material, with the animals showing a broader range in chemical assimilation efficiency values (averaging 17.7% and ranging from 10 to 40%). The ,-HCH bioaccumulation results indicate that when animals incubated under both soil types reached a steady state, they displayed much higher body burdens (1,359.60 pg/animal on OECD soil and 1,085.30 pg/animal on natural soil) than those exposed to contaminated food (43.75 pg/animal). Kinetic models also revealed much lower assimilation and elimination rates in the food experiment (20.66 pg/d and 0.10 pg/d) than in both soil experiments (238.60 pg/d and 350.54 pg/d for the assimilation rate and 0.19 pg/d and 0.32 pg/d for the elimination rate). Differences in results between exposure routes are discussed according to equilibrium-partitioning theory and the enhanced relevance of the substrate exposure route is analyzed under future prospects on chemical toxicity testing using isopods. [source] A11. UV-related skin hazards: allergic photodermatitisJOURNAL OF COSMETIC DERMATOLOGY, Issue 2 2002Paolo Pigatto Cases of dermatitis induced by exposure to ultra-violet radiation are increasingly encountered in clinical practice, with contact allergic photodermatitis accounting for about 10% of cases. Its frequency seems to be increasing, not only as a result of the increased use of cosmetic products and contact with some of the materials of working processes, but above all because of the greater exposure to both natural and artificial sources of UV radiation. Many substances have been defined ,photo-allergising' but their exact prevalence has varied over the years with the introduction and use of new substances in cosmetics and pharmaceutical products. For these, and other reasons, there are few studies concerning the prevalence and incidence of contact allergic photodermatitis in Italy. A total of 2160 patients with clinical histories suggestive of photoallergic contact dermatitis were seen. All patients underwent photopatch tests with haptens proposed by the Gruppo Italiano Ricerca Dermatiti da Contatto plus other substances suggested by each patient's history. 518 patients (24%) were positive to at least one test substance of the standard series or to added substances. Typical photoallergic reactions were seen in 423 subjects, representing 19.5% of the total population. Topical drugs are the substances most frequently involved in photodermatitis. The incidence in our population was about equal for antimicrobial agents, additives to fragrances, and fragrances themselves. Other allergens frequently found were sun screening agents which were the second group of haptens with clear-cut relevance. [source] Endothelin-A-receptor antagonist LU 302146 inhibits electrostimulation-induced bladder contractions in vivoNEUROUROLOGY AND URODYNAMICS, Issue 5 2006J.R. Scheepe Abstract Objectives Endothelin (ET) is a strong constrictor of smooth muscle structures. The relevance of Endothelin-A receptors in the bladder was demonstrated in several in vitro studies. The aim of this functional study was to evaluate the acute effect of the selective ET-A-antagonist LU 302146 (LU) on neurostimulation-induced bladder contractions in vivo. Methods Eight male mini pigs were anesthesized. The bladder was exposed and a double lumen catheter was inserted to perform intravesical pressure (pves) measurements. Laminectomy was performed for sacral anterior root stimulation (SARS) of S2. Four animals received the selective ET-A-antagonist LU, three atropine and one animal was treated with vehicle. Pves was recorded before and after drug administration as well as before and during neurostimulation. At the end of each LU trial, a supplementary application of 4 mg atropine was administered followed by a final SARS. Results In all experiments reproducible pves values were elicited during electrostimulation before administration of the test substance. The selective ET-A-antagonist reduced stimulation-induced bladder contraction by a mean of 57%. Additional administration of atropine inhibited the detrusor contraction almost completely during SARS. The vehicle had no effect on bladder contraction. Conclusions In the presented animal model, ET-1 inhibition with the selective ET receptor-A-antagonist LU 302146 decreases stimulation-induced bladder contraction in vivo. The results suggest that the selective ET-A antagonist LU acts on the atropine-resistant component of efferent detrusor activation since additional administration of atropine almost completely abolish detrusor contraction. This observation in addition to the involvement of ET-1 in bladder smooth muscle proliferation, raises the possibility that ET-receptor antagonists might be beneficial in patients with neurogenic bladder dysfunction or in patients with functional or anatomical BOO. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] Lidocaine/Monoethylglycinexylidide Test, Galactose Elimination Test, and Sorbitol Elimination Test for Metabolic Assessment of Liver Cell BioreactorsARTIFICIAL ORGANS, Issue 6 2010Jörg C. Gerlach Abstract Various metabolic tests were compared for the performance characterization of a liver cell bioreactor as a routine function assessment of cultures in a standby for patient application in clinical studies. Everyday quality assessment (QA) is essential to ensure a continuous level of cellular functional capacity in the development of hepatic progenitor cell expansion systems providing cells for regenerative medicine research; it is also of interest to meet safety requirements in bioartificial extracorporeal liver support systems under clinical evaluation. Quality criteria for the description of bioreactor cultures were developed using primary porcine liver cells as a model. Porcine liver cells isolated by collagenase perfusion with an average of 3 × 109 primary cells were used in 39 bioreactors for culture periods up to 33 days. Measurements of monoethylglycinexylidide synthesis and elimination of lidocaine, galactose elimination, and sorbitol elimination proved to be useful for routine QA of primary liver cell cultures. We demonstrate two methods for dispensing test substances, bolus administration and continuous, steady-state administration. Bolus test data were grouped in Standard, Therapy, Infection/Contamination, and Cell-free control groups. Statistical analyses show significant differences among all groups for every test substance. Post hoc comparisons indicated significant differences between Standard and Cell-free groups for all elimination parameters. For continuous tests, results were categorized according to number of culture days and time-dependent changes were analyzed. Continuous administration enables a better view of culture health and the time dependency of cellular function, whereas bolus administration is more flexible. Both procedures can be used to define cell function. Assessment of cellular function and bioreactor quality can contribute significantly to the quality of experimental or clinical studies in the field of hepatic bioreactor development. [source] Patch testing with components of water-based metalworking fluids: results of a multicentre study with a second seriesCONTACT DERMATITIS, Issue 6 2006Johannes Geier Background:, Although many allergens in metalworking fluids (MWF) are identified, there are still some MWF components, which are not sufficiently investigated concerning their sensitizing properties. Objectives:, To investigate sensitization to 10 frequently used MWF components, which are not part of the established MWF test series, in metalworkers with suspected occupational dermatitis due to MWF. Patients/Methods:, Oleyl alcohol, myristyl alcohol, dimethylolurea, 4,4,-methylenebis morpholine, imazalil, 1-amino-2-propanol (monoisopropanolamine; MIPA), 2-amino-2-ethyl-1,3-propanediol (AEPD), 2,5-bis(n-octyldithio)-1,3,4-thiadiazole, zinc alkyl dithiophosphate and dibenzyl disulfide have been patch tested in 144 patients. Results:, 7 patients reacted positively to the formaldehyde releaser 4,4,-methylenebis morpholine, and 6 of these patients also reacted to formaldehyde and/or other formaldehyde releasers. 4 patients reacted positively to myristyl alcohol tested at 10% petrolatum (pet.). Additionally, 20 doubtful or irritant reactions occurred. 1 patient each reacted positively to oleyl alcohol, MIPA, and AEPD. None of the other test substances mentioned above elicited any clear-cut positive reaction. Patch testing with well-known MWF allergens showed proportions of positive reactions, which were comparable to those from other studies, e.g. 11% to monoethanolamine, 8% to colophonium and 3%,5% to various preservatives. Conclusions:, 4,4,-methylenebis morpholine may be an important MWF allergen, although clinical relevance could not be stated definitely in every case. Myristyl alcohol should not be patch tested at 10% pet., but at a lesser concentration, due to irritant properties. [source] P72 Pigmented patch-test substance and laser Doppler perfusion imagingCONTACT DERMATITIS, Issue 3 2004Bolli Bjarnason Objective:, To investigate if pigment of a dark patch-test substance may affect assessment of perfusion with the laser Doppler imaging technique. Materials:, 13 subjects who previously patch-tested positive with 25% balsam of Peru in petrolatum were re-tested with the same test substance and petrolatum controls applied directly by transparent foils and with much weaker and less pigmented serial doses tested with polyester squares. Readings of perfusion were performed through the test substances and the transparent foils at time intervals up to 4 days while tests were applied and for 5 days following detachment of tests. The instrument set-up of the LDPI was the same as we have suggested for non-pigmented patch-test substances tested on white skin. Results:, Results show that pigment remnants following detachment of the dark pigmented and pasty test substance containing the petrolatum vehicle were prone to affect perfusion assessments by masking detection of perfusion of parts of test sites. A real masking effect is supported by a similar effect with readings of the same tests while they were applied and by no such observable effect with the petrolatum controls or the non-pasty and much less pigmented squares. Conclusion:, The results show that pigment of patch-test substances may affect perfusion assessments with the instrument set-up suggested for non-pigmented substances. [source] Three structurally homologous isothiocyanates exert "Janus" characteristics in human HepG2 cellsENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 3 2009Evelyn Lamy Abstract In this study, we used the single cell gel electrophoresis (SCGE) assay and the micronucleus (MN) test to investigate the DNA damaging effects and the antigenotoxic potencies of three structurally related ITCs in human HepG2 cells. The results show that all three ITCs possess the characteristic of a "Janus" compound, i.e., they exert both significant genotoxicity and antigenotoxicity, depending on the concentrations used in the test systems applied. Regression line analysis of the results derived by SCGE analysis showed genotoxic potency of the ITCs in the following order: 3-methylthiopropyl ITC (MTPITC) > 4-methylthiobutyl ITC (MTBITC) > 5-methylthiopentyl ITC (MTPeITC); however, this order in genotoxic potency was not confirmed by MN analysis. Additionally, the MN test showed significant mutagenicity of the test substances at higher concentrations when compared with the SCGE assay. Twenty-four hour-treatment of the cells with the ITCs, followed by a 1-hr recovery period, showed significant DNA repair in the SCGE assay at a concentration ,10 ,M MTPITC, ,3 ,M MTBITC, and ,0.1 ,M MTPeITC, respectively. In antigenotoxicity studies, the most effective concentration of MTPITC and MTPeITC toward B(a)P-induced DNA damage was 0.1 ,M in both test systems. MTBITC suppressed MN formation in B(a)P-treated cells to the background level at a concentration of 1 ,M. The ambivalent character of the ITCs under studymust be further clarified, especially in the possiblecontext of high dose therapeutic applications. Environ. Mol. Mutagen. 2009. © 2009 Wiley-Liss, Inc. [source] The effect of topically applied salicylic compounds on serotonin-induced scratching behaviour in hairless ratsEXPERIMENTAL DERMATOLOGY, Issue 4 2002J. S. Thomsen Abstract: There is a strong need for antipruritic substances for treating itch in clinical dermatology. In one recent human study, topically applied acetylsalicylic acid has been described to rapidly decrease histamine-induced itch. We have established a model for periferally elicited pruritus by injecting serotonin into the rostral back area (neck) in rats. Using this model, we aimed to investigate the antipruritic potential of four different salicylic compounds, which all possess different skin penetration characteristics. Eighteen rats were studied for 6 weeks. Prior to serotonin injections (2 mg/ml, 50 µl), 10 µl of test substances was applied to a circular area 18 mm in diameter. The four substances were salicylic acid, butyl salicylate, diethylamine salicylate and salicylamide, all solubilized in dimethyl isosorbide to a concentration of 5% w/w. Diethylamine salicylate and salicylamide were previously shown to be slowly absorbed through rat skin in contrast to salicylic acid and butyl salicylate. After serotonin injections, scratching was monitored by video recording for 1.5 h. Compared with the vehicle, a lower number of scratch sequences were seen when diethylamine salicylate (P < 0.001) and salicylamide (P = 0.005) had been applied. The numbers of scratch sequences were lower with diethylamine salicylate and salicylamide than with the vehicle throughout the 1.5-h study period. We conclude that topical application of diethylamine salicylate and salicylamide could suppress serotonin-induced scratching in rats. The antipruritic effect seems to be related to the slow drug release of the two substances. The results may be clinically relevant as serotonin induces itch in humans. [source] Contact allergy and medicinal herbsJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 1 2008Werner Aberer Summary Herbal treatments are becoming increasingly popular, and are often used for internal as well as dermatological conditions, both externally as well as orally. The prevalence of contact sensitization against several plants especially of the Compositae family is quite high in Europe. Sensitization seems to occur relatively frequent with a few species such as arnica, elecampane and tea tree (oil), and occurs rarely with the majority. Testing for plant allergy is problematic because of the limited number of commercially available standardized patch test substances and the danger of active sensitization when testing with plants, parts thereof, or individual extracts. Knowledge about the allergic potential of plants is limited. Although plants are regarded as critical allergens by dermatologists, the number of reported cases of contact dermatitis is relatively small.Many widely used substances are not licensed as drugs or cosmet-ics. While the positive effects are frequently questionable or limited, the side effects are often more evident. Adverse effects of herbal medicines are an important albeit neglected subject in dermatology, which deserves further systematic investigation. [source] Prediction of human pharmacokinetics,gut-wall metabolismJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2007Urban Fagerholm Intestinal mucosal cells operate with different metabolic and transport activity, and not all of them are involved in drug absorption and metabolism. The fraction of these cells involved is dependent on the absorption characteristics of compounds and is difficult to predict (it is probably small). The cells also appear comparably impermeable. This shows a limited applicability of microsome intrinsic clearance (CLint)-data for prediction of gut-wall metabolism, and the difficulty to predict the gut-wall CL (CLGW) and extraction ratio (EGW). The objectives of this review were to evaluate determinants and methods for prediction of first-pass and systemic EGW and CLGW in man, and if required and possible, develop new simple prediction methodology. Animal gut-wall metabolism data do not appear reliable for scaling to man. In general, the systemic CLGW is low compared with the hepatic CL. For a moderately extracted CYP3A4-substrate with high permeability, midazolam, the gut-wall/hepatic CL-ratio is only 1/35. This suggests (as a general rule) that systemic CLGW can be neglected when predicting the total CL. First-pass EGW could be of importance, especially for substrates of CYP3A4 and conjugating enzymes. For several reasons, including those presented above and that blood flow based models are not applicable in the absorptive direction, it seems poorly predicted with available methodology. Prediction errors are large (several-fold on average; maximum-15-fold). A new simple first-pass EGW -prediction method that compensates for regional and local differences in absorption and metabolic activity has been developed. It has been based on human cell in-vitro CLint and fractional absorption from the small intestine for reference (including verapamil) and test substances, and in-vivo first-pass EGW -data for reference substances. First-pass EGW -values for CYP3A4-substrates with various degrees of gastrointestinal uptake and CLint and a CYP2D6-substrate were well-predicted (negligible errors). More high quality in-vitro CLint - and in-vivo EGW -data are required for further validation of the method. [source] Compound-specific bromine isotope analysis of brominated diphenyl ethers using gas chromatography multiple collector/inductively coupled plasma mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 14 2010Henry Holmstrand The bromine isotope composition is potentially diagnostic in both degradation monitoring and source apportionment of organobromines in the environment. A method for compound-specific bromine isotope analysis (,81Br) based on gas chromatography multiple collector inductively coupled plasma mass spectrometry (GC/ICPMS) was developed for common brominated diaromatic compounds. Brominated diphenyl ethers (BDEs) in Bromkal 70-5DE, a technical flame-retardant mixture containing mainly BDEs #47, #99 and #100, were used as test substances, with standard bracketing for the samples achieved through co-injected monobromobenzene (MBB) with a known ,81Br of ,0.39, vs. Standard Mean Ocean Bromine (SMOBr). Three different heated transfer lines were constructed and tested to achieve efficient conduction of the BDEs from the gas chromatograph to the ICPMS instrument. The MBB was analyzed with a precision of 0.4, (1,s, n,=,18). The precision for BDEs was 1.4,1.8, (1,s, n,=,10,12 depending on the congener). The lower precision for the BDEs than for MBB may reflect the heat required to prevent condensation of the analytes in ICP torch assembly. The use of an internal standard of similar chemical structure to the analytes alleviates this problem, as illustrated by a difference of 0.3,±,0.7, (1,s, n,=,6) between the ,81Br values of co-injected methoxy BDE-47 and BDE-47 extracted from whale blubber. Improvements in precision and accuracy may be achieved by the use of a more efficient heating of the torch assembly in conjunction with a set of internal standards that match the target compounds. Copyright © 2010 John Wiley & Sons, Ltd. [source] Lidocaine/Monoethylglycinexylidide Test, Galactose Elimination Test, and Sorbitol Elimination Test for Metabolic Assessment of Liver Cell BioreactorsARTIFICIAL ORGANS, Issue 6 2010Jörg C. Gerlach Abstract Various metabolic tests were compared for the performance characterization of a liver cell bioreactor as a routine function assessment of cultures in a standby for patient application in clinical studies. Everyday quality assessment (QA) is essential to ensure a continuous level of cellular functional capacity in the development of hepatic progenitor cell expansion systems providing cells for regenerative medicine research; it is also of interest to meet safety requirements in bioartificial extracorporeal liver support systems under clinical evaluation. Quality criteria for the description of bioreactor cultures were developed using primary porcine liver cells as a model. Porcine liver cells isolated by collagenase perfusion with an average of 3 × 109 primary cells were used in 39 bioreactors for culture periods up to 33 days. Measurements of monoethylglycinexylidide synthesis and elimination of lidocaine, galactose elimination, and sorbitol elimination proved to be useful for routine QA of primary liver cell cultures. We demonstrate two methods for dispensing test substances, bolus administration and continuous, steady-state administration. Bolus test data were grouped in Standard, Therapy, Infection/Contamination, and Cell-free control groups. Statistical analyses show significant differences among all groups for every test substance. Post hoc comparisons indicated significant differences between Standard and Cell-free groups for all elimination parameters. For continuous tests, results were categorized according to number of culture days and time-dependent changes were analyzed. Continuous administration enables a better view of culture health and the time dependency of cellular function, whereas bolus administration is more flexible. Both procedures can be used to define cell function. Assessment of cellular function and bioreactor quality can contribute significantly to the quality of experimental or clinical studies in the field of hepatic bioreactor development. [source] 2162: New aspects of the Slug Mucosal Irritation (SMI) assay: Detecting ocular stinging, itching and burning sensationsACTA OPHTHALMOLOGICA, Issue 2010J LENOIR Purpose Our eyes are one of the most important senses. They are very sensitive and irritations may occur easily. A screening method for ocular discomfort would be very helpful in the development and refinement of formulations. In the past, the Slug Mucosal Irritation (SMI) assay demonstrated a relation between an increased mucus production (MP) in slugs and an elevated incidence of stinging, itching and burning (SIB) in human eyes. The aim of this study is to compare subjective ocular discomfort caused by shampoos evaluated in volunteers with results of the SIB-procedure. Methods The stinging potency of 1 artificial tear and 10 shampoos was evaluated with the SIB-procedure by placing 3 slugs per treatment group 3 times on 100 µl of the test item. After each 15 min contact period, MP was measured. Evaluation of the results is based upon the total MP during 3 repeated contact periods. Experiments were repeated 3 times. A Human Eye Irritation test with the same test items will be set up (12-period cross-over study, 24 volunteers, study approved by an independent Commission for Medical Ethics, associated with Ghent University Hospital). The participants are dripped 10 µl of a 5% or 10% shampoo dilution in water or the artificial tear in 1 eye, while in the other eye 10 µl of water is administered. The evaluation of the test substances is done both by participants and the ophthalmologist at several time points. Conclusion With the obtained results we will be able to improve the newly developed protocol and examine the predictability with reference to non- and mildly irritating formulations in humans. We hope to conclude that the SIB-procedure is a good tool to predict clinical ocular discomfort. [source] | |||||||||||||