Does Maintaining a Bottle of Adhesive Without the Lid Significantly Reduce the Solvent Content?

This study aimed to evaluate the effect of maintaining a bottle of adhesive without its lid on the solvent loss of the etch-and-rinse adhesive systems. Three 2-step etch-and-rinse adhesives with different solvents (acetone, ethanol or butanol) were used in this study. Drops of each adhesive were placed on an analytical balance and the adhesive mass was recorded until equilibrium was achieved (no significant mass alteration within time). The solvent content of each adhesive and evaporation rate of solvents were measured (n=3). Two bottles of each adhesive were weighted. The bottles were maintained without their lids for 8 h in a stove at 37 ºC, after which the mass loss was measured. Based on mass alteration of drops, acetone-based adhesive showed the highest solvent content (46.5%, CI 95%: 35.8-54.7) and evaporation rate (1.11 %/s, CI95%: 0.63-1.60), whereas ethanol-based adhesive had the lowest values (10.1%, CI95%: 4.3-16.0; 0.03 %/s CI95%: 0.01-0.05). However, none of the adhesives bottles exhibited significant mass loss after sitting for 8 h without their lids (% from initial content; acetone - 96.5, CI 95%: 91.8-101.5; ethanol - 99.4, CI 95%: 98.4-100.4; and butanol - 99.3, CI 95%: 98.1-100.5). In conclusion, maintaining the adhesive bottle without lid did not induce significant solvent loss, irrespective the concentration and evaporation rate of solvent.

Este estudo avaliou o efeito da manutenção do frasco do adesivo sem sua tampa na perda de solvente de sistemas adesivos convencionais. Três adesivos convencionais de 2 passos com diferentes solventes (acetona, etanol ou butanol) foram usados neste estudo. Gotas de cada adesivo foram colocadas em uma balança analítica e a massa dos adesivos foi registrada até a obtenção do equilíbrio (nenhuma alteração significativa com o tempo). O conteúdo de solvente de cada adesivo e a taxa de evaporação dos solventes foram mensurados (n=3). Dois frascos de cada adesivo foram pesados. Os frascos foram mantidos sem suas tampas por 8 h em uma estufa a 37 ºC, seguido pela mensuração da pera de massa. Baseado na alteração de massa das gotas, o adesivo a base de acetona demonstrou o maior conteúdo de solvente (46,5%, IC 95%: 35,8-54,7) e de taxa de evaporação (1,11 %/s, IC95%: 0,63-1,60), enquanto que o adesivo à base de etanol teve os menores valores (10,1%, IC95%: 4,3-16,0; 0,03 %/s IC95%: 0,01-0,05). Entretanto, nenhum dos frascos dos adesivos exibiu perda significante de massa após ficar por 8 h sem suas tampas (% do conteúdo inicial; acetona - 96,5, IC95%: 91,8-101,5; etanol - 99,4, IC95%: 98,4-100,4; e butanol - 99,3, IC95%: 98,1-100,5). Em conclusão, a manutenção do frasco do adesivo sem tampa não induziu perda significante de solvente independente da concentração e da taxa de evaporação do solvente.

Preparation of novel monoclonal antibodies against chelated cadmium ions.

The detection of cadmium ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. Because cadmium ions are too small to stimulate the immune system, high molecular weight immunogens of cadmium are constructed using bifunctional chelators. At present, the most commonly used bifunctional chelator for the preparation of antigens for heavy metal ions is 1-(4-isothiocyanobenzyl) ethylenediamine N,N,N',N'-tetraacetic acid (ITCBE). However, the price of ITCBE is high. So we are interested in a cheaper bifunctional chelator, 1-(4-aminobenzyl) ethylenediamine N,N,N',N'-tetraacetic acid (aminobenzyl-EDTA). Here, cadmium ions were conjugated to carrier proteins using aminobenzyl-EDTA to make artificial antigens. Then, several mice were immunized with the antigen. And monoclonal antibodies (MAbs) against cadmium were produced. Spleen cells of immunized mice were fused with myeloma cells. The resulting hybridomas were screened using protein conjugates which were covalently bound to metal-free EDTA or cadmium. Three hybridoma cell lines (A3, E4 and B5) that produced MAbs with high selectivity and sensitivity were expanded for further study. Cross-reactivities with other metals were below 1 %. These antibodies were used to construct competitive ELISAs. The IC50 for A3 was 8.4 µg/l. The detection range and the lowest detection limit using the antibody A3 was 0.394-64.39 and 0.051 µg/l, respectively. Spike-recovery studies in tap water showed that the antibody A3 could be used for cadmium detection in drinking water.

Immunomodulation of chickens with the nonionic block polymer T150R1.

Chickens injected subcutaneously at one day of age with oil-in-water emulsions of the nonioinic block polymer T150R1 developed higher titres to sheep erythrocytes and killed Brucella abortus than did untreated chickens when they were immunised with the antigens one and two weeks later. The increase was IgM only. Cell-mediated immunity was not affected as measured by blastogenic responses. Morphometric analysis of tissue sections of bursae of Fabricius suggested the polymers were stimulating more rapid migration of B cells to peripheral organs.

Eyedrop-induced allergy: clinical evaluation and diagnostic protocol.

BACKGROUND: In the last few years, adverse reactions to mydriatic eyedrops have been investigated. However, is not still available a standardized protocol, capable of identify the pathogenetic mechanism. In the light of these findings we have evaluated the reliability of a protocol with well established concentration of specific allergens. METHODS: The diagnostic method includes the application of patch test series Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA), medicaments, corticosteroids, local anesthetics, main eyedrops' excipients, pure active principles and extemporaneous preparations with mydriatic eyewashes. At the same time, skin prick test with a solution of atropine sulfate at 1 per thousand and an intradermal test with injection of atropine at 0.01 per thousand were carried out. RESULTS: After patch tests were removed, we detected seven positiveness to the phenylephrine, two to the benzalkonium chloride, one to thiomersal, one to the ethylendiamine and one to the atropine sulfate 1 per thousand. With intradermal tests we obtained three positiveness in patients who reported adverse reactions to atropine. CONCLUSIONS: Our results show that phenylephrine is frequently responsible for allergic conjunctivitis (53.8%). In the case of atropine, even though the limited number of patients suggests to perform more extensive studies, it emerges that our diagnostic protocol is safe and might be able to screen allergic reactions in the field of ophthalmopathies.

Allergy to ethylenediamine and steroid.

Intravenous preparations combining aminophylline and a steroid are used frequently in the treatment of bronchial asthma attacks. However, anaphylactoid reactions to such preparations have been rarely observed. We report the case of a 31-year-old man with aminophylline and steroid allergy. Aminophylline is the ethylenediamine salt of theophylline. In our patient, aminophylline, ethylenediamine and various steroids were found to be positive in the intradermal test. The challenge test with intravenous aminophylline was positive, while that with oral theophylline was negative. Ethylenediamine is used in everyday products such as shellacs and rubber products. In the case of our patient, his asthma worsened following the remodelling of his restaurant. Occupational asthma due to exposure to ethylenediamine is also discussed.

Immediate adverse reaction to aminophylline.

We present a patient who experienced an immediate adverse reaction following intravenous administration of aminophylline. Skin prick, intradermal, and patch tests, RAST and indirect ELISA assays with aminophylline, theophylline and ethylenediamine were negative. A positive histamine release test was found only with ethylenediamine. Single-blind placebo-controlled challenges were positive with aminophylline and negative with theophylline. Our results suggest the reaction was a type I hypersensitivity reaction to ethylenediamine, but a nonimmune mechanism could not be excluded.

Preliminary studies of the TRUE test patch test system in the United States. TRUE Test Study Group.

Comparison of the TRUE Test patch test system with the chamber system recommended by the North American Contact Dermatitis Group showed concordance of results in 98% of tests with nickel, epoxy resin, and ethylenediamine dihydrochloride. Also, a panel of 12 TRUE Test screening allergens tested on 128 patients showed no irritant reactions but did show 46 positive responses of varying intensity. The TRUE Test is a promising alternative to current methods and offers the advantages of easy application and factory quality control.

Results of routine patch testing of 542 patients in Saskatoon, Canada.

542 patients (330 women, 212 men) with suspected allergic contact dermatitis were patch tested to standard series allergens between January 1983 and June 1987. Positive reactions were most frequently seen with nickel (17.4%), ethylenediamine (8.7%), formaldehyde (7.4%), colophony (7.0%), potassium dichromate (6.1%) and neomycin (5.7%). Patients with dermatitis involving the legs were significantly more likely to be allergic to ethylenediamine (p = 0.01) and benzocaine (p = 0.04) than those with dermatitis not involving the legs. Neomycin allergy was not associated with dermatitis involving the legs. Patients allergic to ethylenediamine were significantly more likely to be allergic to neomycin than patients not allergic to ethylenediamine (p = 0.002).

Ethylenediamine dermatitis.

32 ethylenediamine-sensitive patients were studied to determine cross-sensitivity reactions. Reaction to other aliphatic polyamines proved to be very high, whereas no significant result was obtained to antihistamines, either topically or orally.