Heterogeneity of IgE epitopes of vinyl sulphone reactive dye: human serum albumin that react with IgE

Occupational Asthma Induced by the Reactive Dye Synozol Red-K 3BS

Various reactive dyes can elicit occupational asthma in exposed textile industry workers. To date, there has been no report of occupational asthma caused by the red dye Synozol Red-K 3BS (Red-K). Here, we report a 38-year-old male textile worker with occupational asthma and rhinitis induced by inhalation of Red-K. He showed positive responses to Red-K extract on skin-prick testing and serum specific IgE antibodies to Red-K-human serum albumin conjugate were detected using an enzyme-linked immunosorbent assay. A bronchoprovocation test with Red-K extract resulted in significant bronchoconstriction. These findings suggest that the inhalation of the reactive dye Red-K can induce IgE-mediated occupational asthma and rhinitis in exposed workers.

Avoidance therapy in reactive dye-induced occupational asthma: long-term follow-up

BACKGROUND

Previous studies reported that early diagnosis and avoidance therapy are the most important factors for prevention of permanent lung impairment; however, few studies have evaluated the long-term prognosis of reactive dye-induced occupational asthma (RD-OA).

OBJECTIVE

To evaluate the long-term outcomes of RD-OA.

METHODS

Methacholine airway hyperresponsiveness (AHR) and lung functions were evaluated and compared in 26 patients with RD-OA at the time of diagnosis and after complete avoidance of the causative agents. Patients with continued (n = 13) or remitted (n = 6) AHR were further monitored for up to a mean +/- SD of 8.7 +/- 1.8 years.

RESULTS

The AHR resolved in 10 (38%) of 26 patients a mean +/- SD of 2.2 +/- 1.3 years after complete avoidance of RDs; however, prebronchodilator forced expiratory volume in 1 second (FEV1) values were not different. Levels of IgE specific to the RD-human serum albumin complex were markedly decreased at first follow-up in 5 RD-atopic patients from whom paired serum samples were compared (P = .02). The AHR disappeared in an additional 5 patients and improved in 4 by the second follow-up. The FEV1 values also improved compared with diagnosis and first follow-up levels. Favorable prognosis was associated with early diagnosis of RD-OA and complete avoidance of the causative agent. No association was found with smoking history, latent periods, the presence of RD specific IgE, baseline provocation concentration that caused a decrease in FEV1 of 20%, or FEV1.

CONCLUSIONS

Early diagnosis and avoidance therapy are the most important prognostic factors in RD-OA. The AHR and lung function of patients with RD-OA can sometimes be recovered steadily and slowly through avoidance measures.

Cough: occupational and environmental considerations: ACCP evidence-based clinical practice guidelines

OBJECTIVES

This section of the guideline aims to review the role of occupational and environmental factors in causing and contributing to cough. It also aims to indicate when such causes should be considered in a clinical setting, and a general approach to assessment and management.

METHODS

A review was performed of published data between 1985 and 2004 using PubMed. The search terms used included "air pollution," "sick building syndrome," "occupational asthma," "occupational lung disease," "hypersensitivity pneumonitis" (HP), "cigarette smoke," and "asthma." Selected articles were chosen when meeting the objectives, but the extent of articles available and the limited space for this section does not permit a fully comprehensive review of all of these areas, for which the reader is referred to other sections of this clinical practice guideline, the published literature, textbooks of occupational lung disease, or more specific review articles.

RESULTS/CONCLUSIONS

Almost any patient presenting with cough may have an occupational or environmental cause of or contribution to their cough. The importance of this is that recognition and intervention may result in full or partial improvement of the cough, may limit the need for medication/symptomatic treatment, and may improve the long-term prognosis. Nonoccupational environmental contributing factors for upper and lower airway causes of cough include indoor irritant and allergenic agents such as cigarette smoke, cooking fumes, animals, dust mites, fungi, and cockroaches. Causes of HP indoors include birds and fungal antigens. Outdoor pollutants and allergens also contribute to upper and lower airway causes of cough. Occupational exposures can cause hypersensitivity responses leading to rhinitis and upper airway cough syndrome, previously referred to as postnasal drip syndrome, as well as asthma, HP, chronic beryllium disease, and hard metal disease, as well as irritant or toxic responses. The diagnosis is only reached by initially considering possible occupational and environmental factors, and by obtaining an appropriate medical history to determine relevant exposures, followed by objective investigations. This may require referral to a center of expertise.

Homology modeling of falcipain-2: validation, de novo ligand design and synthesis of novel inhibitors

Increasing resistance of malaria parasites, in particular Plasmodium falciparum, demands a serious search for novel targets. Cysteine protease in P. falciparum, encoded by a previously unidentified gene falcipain 2, provides one such target to design chemotherapeutic agents for treatment of malaria. In fact, a few cysteine protease inhibitors have been shown to inhibit growth of cultured malarial parasites. In absence of a crystal structure for this enzyme, homology modeling proved to be a reasonable alternative to study binding requirements of the enzyme. A homology model for falcipain 2 was developed and validated by docking of known vinyl sulfone inhibitors. Further, based on the observations of these studies, novel isoquinoline inhibitors were designed and synthesized, which exhibited in vitro enzyme inhibition at micromolar concentrations.