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601.
Aims:  The aim of our study was to compare, using real-time (Rt) PCR, quantitative levels of five fungal species in three kinds of dwellings.
Methods and Results:  Three groups of homes were recruited: moisture-damaged homes (MDH, n  = 30), allergic patient homes (APH, n  = 25) and paired control homes (CH, n  = 55). Five moulds with allergenic compounds or mycotoxin production characteristics ( Cladosporium sphaerospermum , Penicillium chrysogenum , Aspergillus versicolor , Alternaria alternata and Stachybotrys chartarum ) were quantified using Rt-PCR. Cycle threshold results were expressed in spore equivalent per volume or surface unit using a direct calculation based on a spore standard curve. MDH presented significantly higher amounts of DNA from C. sphaerospermum in both air and surface samples than CH ( P  < 0·001). APH presented slightly elevated amounts of DNA from A. versicolor in both air and surface samples, compared to CH ( P  < 0·05).
Conclusion:  Rt-PCR quantification of targeted fungal species is a rapid, reliable tool that could be included in a global indoor mould evaluation.
Significance and Impact of the Study:  Quantification of C. sphaerospermum using Rt-PCR can help to better target social service intervention in MDH. Quantification of A. versicolor DNA could be informative for characterization of APH.  相似文献   
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Aerobic metabolism of aquatic ectotherms is highly sensitive to fluctuating climates. Many mitochondrial traits exhibit phenotypic plasticity in response to acute variations in temperature and oxygen availability. These responses are critical for understanding the effects of environmental variations on aquatic ectotherms'' performance. Using the European seabass, Dicentrarchus labrax, we determined the effects of acute warming and deoxygenation in vitro on mitochondrial respiratory capacities and mitochondrial efficiency to produce ATP (ATP/O ratio). We show that acute warming reduced ATP/O ratio but deoxygenation marginally raised ATP/O ratio, leading to a compensatory effect of low oxygen availability on mitochondrial ATP/O ratio at high temperature. The acute effect of warming and deoxygenation on mitochondrial efficiency might be related to the leak of protons across the mitochondrial inner membrane, as the mitochondrial respiration required to counteract the proton leak increased with warming and decreased with deoxygenation. Our study underlines the importance of integrating the combined effects of temperature and oxygen availability on mitochondrial metabolism. Predictions on decline in performance of aquatic ectotherms owing to climate change may not be accurate, since these predictions typically look at respiratory capacity and ignore efficiency of ATP production.  相似文献   
605.
The imidazole derivative KK-42 was applied in various experimental conditions to larvae and adult females of Locusta migratoria. The effect of this compound was monitored on the development of larvae, on oocyte growth in adult females and on the development of eggs laid by these females. KK-42 had only minor effects on postembryonic development; anticipation of imaginal moult was never observed. In contrast oocyte and egg development were markedly affected by KK-42: this effect is however not related to modifications of the synthesis of ecdysteroids in the ovaries.  相似文献   
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Calmodulin concentration and cAMP-dependent protein kinase activity have been determined in human sperm samples. No significant differences have been noticed in the motility index of two groups of sperm samples differing in their intracellular concentration of calmodulin. It was however found that a low intracellular clamodulin concentration is frequently associated with particular anomalies of the head and tail region. In contrast, a positive correlation has been demonstrated between the motility index and the whole extractable cAMP-dependent protein activity of the different sperm samples. In suspension s, When the cAMP-dependent protein kinase activity was measured on intact sperm suspensions, a positive correlation between the activity and the motility index was also found.  相似文献   
608.
The effects of C17 juvenile hormone (JH-II) have been investigated in Locusta on morphogenesis, ovarial development, and pigmentation, by means of injections in oil. These effects have been compared with those of injecting C18 juvenile hormone (JH-I) and of implanting corpora allata into Locusta. JH-I and JH-II are similar in their effects upon morphogenesis and pigmentation, and also on ovarial development in which JH-III has been found to be more effective in other insects. Injections of JH-I and JH-II have similar effects to those seen after implanting corpora allata. However in experiments on heart beat (in which the corpora allata have been shown to be involved) JH-I is the only substance to increase the rate of heart beat in the same way as active corpora allata. These observations are discussed, and it is concluded that JH-I is the hormone with effects nearest to those of the corpus allatum hormone itself.  相似文献   
609.
The risk of tumoral seeding in needle biopsies   总被引:4,自引:0,他引:4  
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