PubMed HealthSearch

Biomedical subjects

R Valsecchi

Publications and source records attributed to R Valsecchi.

At least 19 recordsLinked to original sources

Occupational dermatitis from isothiazolinones in the nylon production.

Kathon is a biocide consisting of a mixture of two isothiazolinone derivatives (5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one) in an approximate ratio of 3:1, respectively, and with MgCl2 and Mg(NO3)2 present as stabilizers. The isothiazolinones are marketed under several brand names, and the concentration of the active ingredient varies according to their intended application. At a concentration of 3-15 ppm it shows activity against a wide spectrum of fungi, gram-positive and gram-negative bacteria. Contact allergy to it has been caused by cosmetics and also by products used in the pottery and various other industries. Recently we had the opportunity to observe 6 cases of occupational allergic contact dermatitis from an isothiazolinone mixture named Grotan TK 2 in a large textile industry producing nylon. An oil emulsion containing isothiazolinones is used in the spinning phase of the work cycle to prevent bacterial contamination that would damage yarn quality; furthermore, it helps to decrease the electrostatic charge that is produced by high speed at which the yarn moves and also to decrease the breakage possibility.

Child, Preschool

Contact dermatitis in hairdressers: the Italian experience. Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali.

A multicenter study was performed in 9 Italian centers by members of the GIRDCA, to evaluate the frequency and source of contact sensitization in a group of 302 hairdressers with dermatitis. Occupational habits and use of preventive measures were specifically investigated both in these 302 hairdressers and in a further group of 240 hairdressers who answered a questionnaire. The results showed the presence of an occupationally relevant sensitization in 60.9% of the 302 hairdressers. This proportion included 52 hairdressers who had negative patch tests to the hairdressers' series but showed positive reactions to other allergens, such as nickel, rubber additives, preservatives and fragrances, which were judged relevant to their occupation. Among hair dyes, PPD caused 73 reactions (24.2%), PAP 32 reactions (10.6%), ONPPD 24 reactions (7.9%), and PTD 40 reactions (13.2%). A low incidence of sensitization was detected in our hairdressers to resorcinol and pyrogallol (1.3% for each substance). Among permanent wave allergens, positive reactions to GMTG were found in 11.3% of patients, while ATG gave a lower rate of positive reactions (5.0%). Allergic contact dermatitis due to APS was also relatively common (11.3%). 4 hairdressers in this study gave a positive reaction 30 min after a provocative test with latex gloves, patch testing to the rubber series being negative. Enquiry regarding preventive measures revealed that the majority of hairdressers use gloves when doing hair dyeing, but rarely use them for washing dyed hair or for doing permanent waving. The infrequent use of preventive measures by Italian hairdressers was confirmed by the results of the questionnaire, and possibly explains the high frequency of skin problems (12.5%) in the hairdressing population that was specifically interviewed.

Adolescent

Eyelid dermatitis: an evaluation of 150 patients.

This study was performed to evaluate eyelid dermatitis in a group of patients of our Allergy Unit between January 1990 and April 1991. Among the 1158 patients seen during this period, 150 had eyelid dermatitis: 135 females and 15 males, with a mean age of 35 years. Of the 150 patients with eyelid dermatitis, 54 had eczema localized to the eyelids only, 49 to the eyelids and face, 19 to the eyelids and hands, and 28 to the eyelids and other sites. 98 patients (65.3%) were diagnosed as having allergic contact dermatitis, 25 (16.6%) irritant contact dermatitis, 21 (14%) atopic dermatitis, and 6 (4%) seborrhoeic dermatitis. Patch test reactions to nickel sulphate, Kathon CG and fragrance-mix occurred more frequently in patients with eyelid dermatitis than in those without.

Adult

Alopecia areata and interleukin-2 receptor.

Interleukin-2 (IL-2) is a lymphokine produced by activated T cells and its receptor (IL-2R) is expressed on T cells; one of the IL-2R components can be measured as a soluble serum protein (sIL-2R). Levels of sIL-2R were measured as a sign of T cell activation in serum of 12 patients suffering from alopecia areata (totalis or universalis) and in a group of healthy control subjects. An enzyme-linked immunosorbent assay was used to determine the levels of sIL-2R in blood samples drawn during both the active and resting phase of the disease. In patients with alopecia areata in active phase the sIL-2R concentrations were significantly higher than in stable phase and in controls. The biologic role of sIL-2R is still unknown, but one could speculate that T lymphocyte activation with subsequent secretion of IL-2 and IL-2R expression may contribute to the immune inflammatory mechanism of alopecia areata.

Adolescent