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211.
Summary. The larvae of the hawkmoth species Hyles euphorbiae have a conspicuous aposematic colouration and show gregarious behaviour. It has thus been suggested that they sequester phorbol esters from their food plants which include different species of the genus Euphorbia (Euphorbiaceae) for chemical protection against predators. To test this hypothesis in more detail, we fed larvae an artificial diet with three doses of 12-tetradecanoyl-phorbol-13-acetate (TPA), then examined the faeces and the larval tissues, such as integument, haemolymph and gut of the caterpillars for the presence of TPA. In order to determine the ability of the larvae to detoxify phorbol esters, other larvae were directly injected with a TPA solution and analysed in the same manner. Our study indicates that the larvae of Hyles euphorbiae do not sequester phorbol esters. Upon oral application TPA was not found in the larval integument or the haemolymph. Instead, it was mostly metabolised (about 70–90%). Nevertheless, about 10-30% were retained and recovered in the faeces. The larvae were also able to metabolise and thus detoxify the phorbol ester when TPA was injected directly into the body. These hawkmoth caterpillars are relatively large and have a gut full of plant material, which they regurgitate into the direction of the predator when attacked in nature. Since phorbol esters are very potent toxins and irritants, we postulate that the gut content (and especially the plant slurry disgorged as regurgitant from the anterior gut) alone could be aversive for a potential predator, even if some metabolism has taken place. Thus, although H. euphorbiae caterpillars do not actively sequester phorbol esters, their aposematic colouration appears to be based on chemical defence through phorbol esters retained in the gut.  相似文献   
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Eight pregnancies at risk for cystic fibrosis have been monitored by first-trimester prenatal diagnosis with DNA amplification analysis. The polymerase chain reaction (PCR) was used in all cases to amplify the region detected by KM 19. In two cases, the region detected by CS·7, another DNA probe tightly linked to the CF locus, was also examined. The results of the PCR determinations were confirmed using the Southern blotting procedure, by segregation analysis of restriction fragment length polymorphisms (RFLPs) relative to XV-2c, J3·11, metH, metD, and KM19 probes.  相似文献   
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Bivalve mollusks as filter-feeders concentrate in their digestive tissue microorganisms likely present in the harvesting water, thus becoming risky food especially if consumed raw or poorly cooked. To eliminate bacteria and viruses eventually accumulated, they must undergo a depuration process which efficacy on viruses is on debate. To better clarify the worth of the depuration process on virus elimination from mussels, in this study we investigated rotavirus kinetics of accumulation and depuration in Mytilus galloprovincialis experimentally contaminated. Depuration process was monitored for 9 days and virus residual presence and infectivity were evaluated by real time quantitative polymerase chain reaction, cell culture and electron microscopy at days 1, 2, 3, 5, 7, 9 of depuration. Variables like presence of ozone and of microalgae feeding were also analyzed as possible depuration enhancers. Results showed a two-phase virus removal kinetic with a high decrease in the first 24 h of depuration and 5 days necessary to completely remove rotavirus.  相似文献   
216.
Detection of norovirus (NoV) and hepatitis A virus (HAV) on fruits and vegetables using current standard methodologies can be inefficient. Method optimisat  相似文献   
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Durum wheat (Triticum turgidum var. durum) is an important crop in Europe, particularly in the Mediterranean countries. Fusarium head blight (FHB) is considered as one of the most damaging diseases, resulting in yield and quality reduction as well as contamination of grain with mycotoxins. Three winter durum wheat cultivars originating from Austria, Slovakia, and Poland were analyzed during 2012–2014 seasons for FHB incidence and Fusarium mycotoxin accumulation in harvested grain. Moreover, the effects of sowing density and delayed sowing date were evaluated in the climatic conditions of Southern Poland. Low disease severity was observed in 2011/2012 in all durum wheat cultivars analyzed, and high FHB occurrence was recorded in 2012/2013 and 2013/2014 seasons. Fusarium graminearum was the most abundant pathogen, followed by Fusarium avenaceum. Through all three seasons, cultivar Komnata was the most susceptible to FHB and to mycotoxin accumulation, while cultivars Auradur and IS Pentadur showed less symptoms. High susceptibility of cv. Komnata was reflected by the number of Fusarium isolates and elevated mycotoxin (deoxynivalenol, zearalenone, and moniliformin) content in the grain of this cultivar across all three seasons. Nivalenol was identified in the samples of cv. Komnata only. Genotype-dependent differences in FHB susceptibility were observed for the plants sown at optimal date but not at delayed sowing date. It can be hypothesized that cultivars bred in Austria and Slovakia show less susceptibility towards FHB than the cultivar from Poland because of the environmental conditions allowing for more efficient selection of breeding materials.  相似文献   
219.
Introduction. Paramedics are at risk of occupational blood exposure, increased by the immediacy of provided treatment. However, the issue has not been acknowledged to date by any research in Europe. Methods. This research aimed at assessing occupational blood exposure among paramedics in Poland. Respondents represented 21 Polish medical institutions. Their participation was voluntary and anonymous. Paramedics were provided with a self-directed job-specific questionnaire adapted to Polish conditions from an original US version. Results. 118 paramedics participated in the study from institutions constituting the National Emergency Medical System in Poland; including ambulance crews, Helicopter Emergency Medical Services and emergency department employees. Occupational exposure was reported by 18.64% of respondents and the main route of exposure was needlestick events. Conclusions. There is a further need to improve education among paramedics concerning the threat of being infected with blood-borne pathogens through all existing routes. Our findings point to the problem as being hidden and considered a shameful issue.  相似文献   
220.
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