Isocyanate-induced asthma, which is the most common type of occupational asthma, has been difficult to diagnose and control, in part, because the biological mechanisms responsible for the disease and the determinants of exposure are not fully defined. To help address these issues, we recently established a murine model of toluene diisocyanate (TDI) asthma using inhalation exposure paradigms con...

BACKGROUND Histamine synthesized by histidine decarboxylase (HDC) from L-histidine is a major chemical mediator in the development of nasal allergy which is characterized by nasal hypersensitivity. However the regulatory mechanism of histamine synthesis by HDC remains to be elucidated. The objectives of the present study were to examine the changes of histamine content, HDC activity and HDC mRN...

BACKGROUND Isocyanates constitute a group of highly reactive, low molecular weight chemicals used worldwide for polyurethane manufacturing. The occupational exposure to these compounds is a major cause of occupational asthma, thus it is very important to monitor their concentration in the workplace atmosphere. The aim of the study was to measure the concentration of 4,4'-methylenediphenyl diiso...

The electrochemical oxidation of 2,4-toluene diisocyanate (2,4-TDI) in an ionic liquid (IL) has been systematically characterized to determine plausible electrochemical and chemical reaction mechanisms and to define the optimal detection methods for such a highly significant analyte. It has been found that the use of an IL as the electrolyte allows the oxidation of 2,4-TDI to occur at a less po...

Toluene diisocyanate (TDI) is a potent low molecular weight chemical sensitizer and a leading cause of chemical-induced occupational asthma. The regulatory potential of microRNAs (miRNAs) has been recognized in a variety of disease states, including allergic disease; however, the roles of miRNAs in chemical sensitization are largely unknown. In a previous work, increased expression of multiple ...

Asthma is a chronic disease characterized by increased bronchial responsiveness ranging in degree from mild ~o severe. AU:Way inflammation has been receiving 1ncrcased auenuon as the major mechanism in bronchial hypcrrcsponsiveness. Many stimuli known to induce airwa~ inflam~ation ~lso i.ncrease bronchial reactivity, e.g. v~ral rcsp1ratory mfectJOns, ozone, antigens and chem1ca ls such as tolue...

Eighty-seven cases of occupational asthma induced by toluene diisocyanate (TDI) were diagnosed by an inhalation challenge with TDI and methacholine. After an average follow-up interval of 11 yrs, all subjects were re-examined. Of the 87 subjects examined, 13 (15%) had remained in the same job, 44 (50.5%) had been removed from exposure for <10 yrs and 30 (34.5%) had been removed for >10 yrs. The...

Immune contact dermatitis is an inflammation of the skin resulting from exposure to allergens in the environment. The aim of this study was to compare the actions of lactoferrin (LF), a natural immunomodulator, on the elicitation phases of the cellular and humoral, cutaneous immune responses to oxazolone and toluene diisocyanate (TDI), respectively. LF was given i.v. in a 10 mg/mouse dose, toge...

Exposure to isocyanates is known to have respiratory effects in workers and therefore it is essential to monitor the occupational exposure. An earlier study of a continuous foaming plant using toluene diisocyanate (TDI) showed that the exposure to isocyanates can be high. Since then several preventive actions were implemented at the plant. The aim of this study was to observe the effect of thes...

Isocyanate is the most prevalent agent in occupational asthma(OA) in Korea. We analyzed 43 toluene diisocyanate(TDI) induced OA patients of whom 81% were found to be spray painters. The bronchial sensitivity of all subjects was confirmed by TDI-bronchial challenge test. Serum-specific IgE antibodies to isocyanate-human serum albumin(HSA) conjugate were detected by RAST technique(Pharmacia, Swed...