Asthma human studies

French, J. G., V. Hasselblad, R. Johnson, and K. E. McClain. The Association of Suspended Nitrates in Ambient Air with Aggravation of Asthma. (Inhouse Report) Human Studies Laboratory, National Environmental Research Center. Research Triangle Park, N.C. U.S. Environmental Protection Agency, 1975. 

Many investigators have studied the therapeutic effects of yogurt and LAB commonly used in yogurt production on diseases such as cancer, infection, gastrointestinal disorders, and asthma. Because the immune system is an important contributor to all of these diseases, the immunostimulatory effects of yogurt were studied by several investigators. Most of these studies used animal models few human studies on the immunostimulatory effects of yogurt have been conducted. 

Few human studies or clinical trials examining the potential health and/or therapeutic applications of rooibos have been reported. Dnring the early 1980s, a small (n=7) study was conducted in hnmans snffering from asthma or hay fever. Neither the ingestion of traditional rooibos nor the topical apphcation of a rooibos poultice exhibited any antihistaminic effects (75). Nearly a decade later, another human study was pubhshed that showed a positive effect an infusion of rooibos had on patients with atopic dermatitis and herpes simplex viral infection 74). A decreased itching and indnced-inflammation was reported as well as a decreased incidence of herpes simplex. As yet, no hnman studies on inunune responses have been published. 

While guinea pigs are one of the oldest animal models of human asthma, mechanistic studies in this species are limited... 

Based on a LOAEL of 2 ppm for respiratory effects—bronchial obstruction (30% change in airway resistance) in 2/10 persons with asthma in the Jappinen et al. (1990) study, an acute inhalation MRL of 0.07 ppm was derived. An uncertainty factor of 30 was applied to the LOAEL 10 for the use of a LOAEL and 3 for human variability. Since persons with severe asthma were excluded from the study, an uncertainty factor of 3 is needed to protect all sensitive individuals including children. Further details on the derivation of this MRL can be found in the MRL worksheets in Appendix A of this profile. Based on aNOAEL of 30.5 ppm for respiratory effects in mice observed in the CUT (1983a) study, an intermediated MRL of 0.03 ppm was derived. The NOAEL is adjusted for intermittent exposure and the NOAEL[hec] is calculated. An uncertainty factor of 30 is then applied 3 for extrapolating from animals to humans and 10 for human variability. Further details on this MRL can be found in the MRL worksheets in Appendix A of this profile. 

Nearly all pharmacogenomic studies conducted to date in asthma have been case control studies. A major criticism of genetic case control studies of human diseases has been potentially undetected population stratification. Population stra-... 

Efforts to incorporate SNP studies into environmental/occupational epidemiology investigations have focused on examining hypothesis-driven associations between exposures and specific polymorphisms. Most common human diseases such as asthma,... 

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