BackgroundRisk assessment for GMOs such as Bt maize requires detailed data concerning pollen deposition onto non-target host-plant leaves. A field study of pollen on lepidopteran host-plant leaves was therefore undertaken in 2009–2012 in Germany. During the maize flowering period, we used in situ microscopy at a spatial resolution adequate to monitor the feeding behaviour of butterfly larvae. The plant-specific pollen deposition data were supplemented with standardised measurements of pollen release rates and deposition obtained by volumetric pollen monitors and passive samplers.ResultsIn 2010, we made 5377 measurements of maize pollen deposited onto leaves of maize, nettle, goosefoot, sorrel and blackberry. Overall mean leaf deposition during the flowering period ranged from 54 to 478 n/cm2 (grains/cm2) depending on plant species and site, while daily mean leaf deposition values were as high as 2710 n/cm2. Maximum single leaf-deposition values reached up to 103,000 n/cm2, with a 95 % confidence-limit upper boundary of 11,716 n/cm2.ConclusionsDaily means and variation of single values uncovered by our detailed measurements are considerably higher than previously assumed. The recorded levels are more than a single degree of magnitude larger than actual EU expert risk assessment assumptions. Because variation and total aggregation of deposited pollen on leaves have been previously underestimated, lepidopteran larvae have actually been subjected to higher and more variable exposure. Higher risks to these organisms must consequently be assumed. Our results imply that risk assessments related to the effects of Bt maize exposure under both realistic cultivation conditions and worst-case scenarios must be revised. Under common cultivation conditions, isolation buffer distances in the kilometre range are recommended rather than the 20–30 m distance defined by the EFSA.Electronic supplementary materialThe online version of this article (doi:10.1186/s12302-016-0082-9) contains supplementary material, which is available to authorized users.
The efficacy and tolerance of a capsicum plaster in non-specific low back pain was investigated in a double-blind, randomised, placebo-controlled multicentre parallel group study. A total of 320 patients were randomly assigned to two groups of n=160 subjects treated by the active or the placebo plaster. The main outcome measures used were a compound pain subscore of the Arhus low back rating scale (continuous variable), and a response criterion of a reduction in pain subscore=30% from baseline to final assessment (secondary, non-continuous variable). In addition, the partial pain scores, disability and mobility restriction subscores, the total score of the Arhus low back rating scale, the global evaluation of efficacy by investigator and patient, adverse events, a patient questionnaire on use of the plaster, and an evaluation of tolerance by investigator and patient were obtained. After 3 weeks treatment with capsicum and placebo plaster respectively, the compound pain subscore was reduced by 42% (capsicum) and 31% (placebo) from values on entry. Responder rate was 67% versus 49% (p=0.002). The investigators rated efficacy as "excellent" or "good" by 74% and 36%; the patient's efficacy rating "symptomfree" or "improved" reached 82% and 50%. Adverse local drug reactions were found in 12 patients (7.5%) on capsicum and 5 (3.1%) on placebo. No systemic side-effects were observed. The superiority of the treatment of chronic non-specific low back pain with capsicum plaster compared to placebo was clinically relevant and highly statistically significant. The capsicum plaster offers a genuine alternative in the treatment of non-specific low back pain.
Topically applied capsaicin (CAS 404-86-4) induces the release of substance P, a neurotransmitter, from sensory C-fibres. In addition, there is a specific blockade of transport and de-novo synthesis of substance P. As a result, repeated applications of capsaicin bring about a long lasting desensitisation to pain (increase of pain threshold). The desensitising effect is fully reversible. The confirmed pharmacodynamic actions and a number of double-blind clinical studies indicate that local capsicum preparations are very suitable for the treatment of neuropathic pain or musculoskeletal disorders, with or without inflammatory components. In a double-blind, randomised parallel-group study a capsicum plaster was compared with a placebo for 3 weeks in 154 patients with non-specific back pain. Inclusion criteria were a history of back pain for a minimum period of 3 months and a degree of pain of 5 or more on an eleven grade visual analogue scale. The principal target variable consisted of the score of 3 combined pain scales. Secondary efficacy measures were tests of mobility, a disability index (in the context of Arhus low back rating scale) and global assessments by physicians and patients. For patients to be rated as responders their total pain score at the final examination after 3 weeks of treatment had to show a reduction by at least 30% of the baseline value. The study unequivocally achieved the target criterion with a rate of responders in the capsicum group of 60.8% against 42.1% in the placebo group (p = 0.0219). The sum of the 3 separate pain scales decreased more markedly in the capsicum group than in the placebo group (38.5% compared to 28.0%; p = 0.002). Relatively slight improvements of the impaired mobility and the functional status are explained by the characteristics of the disorder treated. The efficacy ratings by observers and patients was definitely in favour of capsicum. Adverse effects--mostly harmless and resolving spontaneously--were reported by 15 patients in the capsicum group and by 9 in the placebo group. The tolerance ratings by investigators and patients were superior to the placebo product. This, however, partly is due to the local pharmacological actions of the drug. As in comparably positive randomised studies with capsaicin cream in patients with osteoarthritis or fibromyalgia it was shown that a capsicum plaster preparation can also be used to advantage in chronic non-specific back pain.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.