Passive cigarette smoke-challenge studies: increase in bronchial hyperreactivity.

Degree and duration of bronchial hyperreactivity (BHR) after environmental tobacco smoke (ETS) inhalation was assessed in 31 smoke-sensitive subjects with asthma who exhibited lower airway symptoms on ETS exposure (group I) and 39 smoke-sensitive subjects without asthma who manifested only upper airway symptoms on cigarette-smoke exposure (group II). Subjects were challenged with ETS for 4 hours in a static-test chamber. The atmosphere was continuously monitored for airborne particulate levels (800 cpm), total suspended particulates (1266 +/- 283 micrograms/m3), and airborne nicotine levels (226 +/- 49 micrograms/m2).

Skin test reactivity to whole body and fecal extracts of American (Periplaneta americana) and German (Blatella germanica) cockroaches in atopic asthmatics.

Forty-six atopic asthmatic subjects aged 3 to 58 years attending the allergy clinic of a university hospital were evaluated for prick skin test reactivity with commercially available extracts of cockroach (CCE) and house dust (HD). Additionally, skin testing was performed with American cockroach whole body (AWBE) and fecal extracts (AFE) as well as German cockroach whole body (GWBE) and fecal extracts (GFE) prepared in our laboratory. Commercial cockroach extract was prepared from American, German, and Oriental cockroach whole bodies.

Asthmatic responses to passive cigarette smoke: persistence of reactivity and effect of medications.

The present study assessed the persistence of cigarette-smoke reactivity and the effects of drug pretreatment on bronchial responsiveness to environmental tobacco smoke (ETS). Two groups of subjects were chosen for the study. Group I consisted of 15 atopic smoke-sensitive subjects with asthma, six of whom were defined "reactors" and nine "nonreactors" to ETS challenge.

Comparison of cockroach allergenic activity in whole body and fecal extracts.

Previous studies have established cockroach allergens as important sensitizing agents in the induction/exacerbation of urban asthma. The present investigation compared saline extracts of American cockroach (Periplaneta americana) whole bodies and feces and German cockroach (Blattella germanica) whole bodies and feces as important sources of allergens. All extracts were tested before or after gel filtration on Sephadex G-75 columns (fraction 2) as previously described.

Identification and characterization of important cockroach allergens.

Allergens extracted from American and German cockroach species have been identified as significant sensitizing agents in the induction/exacerbation of asthma. In the present study, gel-filtration fractions of saline extracts of American cockroach (Periplaneta americana) whole bodies (AWBE fraction 2) and German cockroach (Blattella germanica) whole bodies (GWBE fraction 2) were used to identify and characterize important cockroach allergens by immunoprinting. In addition, allergens from AWBE and GWBE fractions 2 were additionally fractionated by chromatofocusing on polybuffer exchanger.