Occupational asthma and occupational rhinitis in hairdressers

BACKGROUND: Hairdressers are at risk for occupational respiratory diseases, but the risk factors, causal agents, and underlying mechanisms are not completely defined. AIM: To describe the features of a large group of hairdressers consecutively referred to our center for suspected occupational asthma (OA) over an 8-year period, the type of occupational respiratory diseases, the etiologic agents, and the diagnostic tests. RESULTS: Forty-seven hairdressers (mean age, 25 years; range, 17 to 52 years) were studied. On the basis of the response to the specific inhalation challenge (SIC), 24 patients received a diagnosis of OA (51.1%), which was due to persulfate salts in 21 patients (87.5%), permanent hair dyes in 2 patients (8.3%), and latex in 1 patient (4.2%). Thirteen of these 24 patients (54.2%) also received a diagnosis of occupational rhinitis, which was due to persulfate salts in 11 patients (84.6%) and to paraphenylenediamine in two patients (15.4%). Patients with persulfate asthma had a long period of exposure to bleaching agents, a long latent period between the start of exposure and the onset of symptoms, and a prevalent eosinophilic airway inflammation in induced sputum. The skin-prick test with ammonium persulfate performed in a subset of patients gave negative results CONCLUSIONS: In the present study, we confirmed that persulfate salts are the major agents involved in OA and occupational rhinitis in hairdressers. The positive response to the SIC in only a part of the population of symptomatic exposed workers, the period between the starting of exposure and the onset of symptoms, the type of response to the SIC, and the high frequency of association of asthma with other diseases such as dermatitis and rhinitis suggest an immunologic mechanism that remains to be elucidated.     

Genetic inactivation of Nrf2 prevents clonal expansion of initiated cells in a nutritional model of rat hepatocarcinogenesis

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Immune reconstitution and early infectious complications following nonmyeloablative hematopoietic stem cell transplantation

Non-myeloablative stem cell transplantation (NMT) has been increasingly used in compromised patients who would otherwise have been unable to undergo allotransplant. There is little understanding of the kinetics of immune reconstitution and its influence on infective complications following NMT. The aim of present study was to evaluate lymphocyte subset reconstitution over the first 12 months post-transplant in 15 adult patients receiving NMT with comparison to that of 30 patients grafted with a conventional hemopoietic stem cell transplantation (HSCT). NMT recipients were conditioned with fludarabine-based conditioning regimens. Peripheral blood stem cell (PBSC) was the source of stem cells in 13 NMT recipients and in 24 conventional HSCT recipients. Absolute numbers of helper (CD4+) T cells, naive (CD4+ CD45RA+) and memory (CD4+ CD45RO+) T cells as well as suppressor (CD8+) T cells, CD19+ B cells and NK cells were comparable in the two groups at all time points after transplantation. A median value of 200 CD4+ T cells/microl was achieved at 2 months post-transplant by the NMT and HSCT recipients. The CD4:CD8 ratio remained severely depressed throughout the study period. Almost all CD4+ lymphocytes expressed CD45RO antigen in the both groups of patients B lymphocytes showed low counts throughout the entire study period in both groups. Bacteremia and CMV antigenemia occurred respectively in 13 and 36% of the patients in the NMT group and in 15 and 39% of the patients in the HSCT group. Our preliminary data indicate that patients receiving a NMT have a lymphocyte reconstitution similar to that observed in patients who received a conventional HSCT. The incidence of bacteremia and CMV infection were not significantly different between the groups. Nevertheless, due to the small sample size, these results should be considered suggestive rather than definitive.