Allergy immunotherapy for allergic rhinitis effectively prevents asthma: Results from a large retrospective cohort study.

BACKGROUND: Allergic rhinitis (AR) is a main risk factor for the development of asthma. Two randomized open-label trials indicated that allergy immunotherapy (AIT) prevents the onset of asthma in patients with AR. However, these trials have methodological limitations, and it is unclear to what extent this experimental efficacy translates into clinical effectiveness. OBJECTIVES: We sought to investigate the effectiveness of AIT to prevent asthma in patients with AR. METHODS: Using routine health care data from German National Health Insurance beneficiaries, we identified a consecutive cohort of 118,754 patients with AR but without asthma who had not received AIT in 2005. These patients were stratified into one group starting AIT in 2006 and one group receiving no AIT in 2006. Both groups were observed regarding the risk of incident asthma in 2007 to 2012. Risk ratios (RRs) were calculated with generalized linear models by using a Poisson link function with robust error variance and adjustment for age, sex, health care use because of AR, and use of antihistamines. RESULTS: In a total of 2431 (2.0%) patients, AIT was started in 2006. Asthma was newly diagnosed from 2007-2012 in 1646 (1.4%) patients. The risk of incident asthma was significantly lower in patients exposed to AIT (RR, 0.60; 95% CI, 0.42-0.84) compared with patients receiving no AIT in 2006. Sensitivity analyses suggested significant preventive effects of subcutaneous immunotherapy (RR, 0.54; 95% CI, 0.38-0.84) and AIT including native (nonallergoid) allergens (RR, 0.22; 95% CI, 0.02-0.68). AIT for 3 or more years tended to have stronger preventive effects than AIT for less than 3 years. CONCLUSION: AIT effectively prevents asthma in patients with AR in a real-world setting. Confounding by indication cannot be excluded but would lead to an underestimation of the true preventive effects of AIT.

Oviposition in Delia platura (Diptera, Anthomyiidae): the role of volatile and contact cues of bean.

The choice of a suitable oviposition site by female insects is essential for survival of their progeny. Both olfactory and contact cues of the oviposition site may mediate this choice. The polyphagous Delia platura (Diptera: Anthomyiidae), a severe agricultural pest of numerous crops, lays eggs in the soil close to germinating seeds. Maggots feed upon the cotyledons. Only little is known about the cues guiding oviposition behavior. In this study, the effects of both olfactory and contact cues of beans (Phaseolus vulgaris) on oviposition of D. platura females were tested. Egg deposition on germinated beans was preferred to egg deposition on ungerminated beans or on beans in different postgerminating developmental stages. Olfactory cues of germinating beans alone stimulated female flies to lay eggs. Additional contact cues of germinating beans seemed to enhance the response, but the difference was not significant. Surface extracts of germinating beans sprayed on surrogate beans showed that both polar and nonpolar substances stimulated oviposition of D. platura flies. Gas chromatography-electroantennographic detection recordings of head space samples of germinating beans showed positive response of females to different compounds. We conclude that olfaction plays a major role when D. platura females are searching for oviposition sites. Volatile compounds released from germinating beans such as 4-hydroxy-4-methyl-2-pentanone, 1-hepten-3-one, 1-octen-3-ol, and 3-octanone should be considered as key compounds that mediate oviposition behavior. The use of different sensory modalities by closely related species of Delia is discussed.

Isothiocyanates stimulating oviposition by the diamondback moth, Plutella xylostella.

Recognition of cabbage as a host plant for the diamondback moth (DBM) has previously been shown to depend on compounds that are extracted by soaking intact foliage in chloroform. Analysis of such chloroform extracts by open column chromatography has now resulted in the isolation of highly active fractions that elicit oviposition on treated filter papers. Further separation of these fractions by high-performance liquid chromatography revealed the presence of two distinct groups of active compounds that may be classified as volatile and non-volatile. The two prominent volatile components were separated and identified by mass spectrometry as the isothiocyanates, iberin (3-methylsulfinylpropyl isothiocyanate) and sulforaphane (4-methylsulfinyl-3-butenyl isothiocyanate). Subsequent bioassays of a range of isothiocyanates showed that iberin and sulforaphane were the most active of those tested. Other isothiocyanates with sulfur in the side chain were also active, whereas alkyl and phenyl isothiocyanates had only limited activity. In electrophysiological experiments, electroantennograms (EAGs) indicated positive responses of moth antennae to the isothiocyanates that were most active in behavioral assays. Since sulforaphane has been identified as a major inducer of anticarcinogenic activity in mouse tissue, a synthetic analog (exo-2-acetyl-5-isothiocyanatonorbornane) that shows similar inducer activity was tested on DBM. This bicyclic analog was highly active in both behavioral and EAG assays, suggesting similarity in receptor sites for the two types of biological activity.