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81.
Eicosanoids affect the immunity of several pathogen/insect models, but their role on the Anopheles gambiae response to Plasmodium is still unknown. Plasmodium berghei-infected mosquitoes were injected with an eicosanoid biosynthesis inhibitor, indomethacin (IN), or a substrate, arachidonic acid (AA), at day 7 or day 12 post-infection (p.i.). Salivary gland invasion was evaluated by sporozoite counts at day 21 p.i. IN promoted infection upon sporozoite release from oocysts, but inhibited infection when sporozoites were still maturing within the oocysts, as observed by a reduction in the number of sporozoites reaching the salivary glands. AA treatment had the opposite effect. We show for the first time that An. gambiae can modulate parasite survival through eicosanoids by exerting an antagonistic or agonistic effect on the parasite, depending on its stage of development.  相似文献   
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Fifth-instar Erinnyis ello larvae eat 2.1 times their own weight per day of Euphorbia pulcherrima leaves, with a coefficient of digestibility of 45% and an efficiency of food conversion into tissue of 25%. The food takes about 150 min to go through the gut. Midgut contents have a pH of 9.3–9.8, depending on the region. Cellulase is absent from the gut in E. ello. Significant gut hydrolase activities are found only in midgut. Amylase and trypsin occur in the midgut tissue and contents and in regurgitated material, whereas aminopeptidase, α-glucosidase, β-glucosidase and trehalase are found in major amounts in the midgut tissue, in minor amounts in the midgut contents and are absent from regurgitated material. The results support the hypothesis that digestion starts in the endoperitrophic space under the action of amylase and trypsin and is largely completed in the ectoperitrophic space through the catalytic action of several oligomer and dimer hydrolases. Involvement of a membrane-bound aminopeptidase in the terminal digestion of oligopeptides cannot, at present, be excluded. The finding that less than 7% of the total amylase and trypsin are excreted, after a time identical to the passage time of the food bolus, leads to the proposal for the existence of some mechanism by which those enzymes are recovered from the undigested food before it is excreted.  相似文献   
84.
The chemical composition and in vitro biological activities of the essential oil (EO) of Micromeria macrosiphon Coss. and M. arganietorum (J. Emb.) R. Morales, two Lamiaceae endemic to south Morocco, were investigated. GC/MS analysis resulted in the identification of 36 metabolites from the EO of M. macrosiphon, 45 from M. arganietorum. Borneol was the major metabolite in both oils and together with related derivatives such as camphor, accounted for 2/3 of the EO of M. macrosiphon, 1/3 of those of M. arganietorum. Pinene and terpinene derivatives were also present in high proportions. From a chemotaxonomic point of view, the composition of the examined samples may be related to those of other species endemic to Macaronesia. Both EOs showed significant toxicity towards liver HepG2 and melanoma B16 4A5 tumor cell lines at 100 μg/mL; however, they were also cytotoxic towards S17 normal cell lines, with a selectivity index <1. No antibacterial activity was noticed against 52 strains at 100 μg/mL.  相似文献   
85.
Objective: To examine binge-eating disorder (BED) and its association with obesity, weight patterns, and psychopathology in a Brazilian sample of female participants of a weight-loss program in São Paulo, Brazil. Research Methods and Procedures: Two hundred and seventeen overweight (body mass index ≥ 25 kg/m2) women, ages 15 to 59 years, enrolled in the Weight Watchers Program were recruited for the study at a program branch meeting after completing the Questionnaire on Eating and Weight Patterns–Revised, Beck Depression Inventory, and the Toronto Alexithymia Scale-20. Participants were categorized into four groups: those who met questionnaire criteria for BED, those who met questionnaire criteria for bulimia nervosa (BN), those that reported binge eating but did not meet all the criteria for any eating disorder (BE), and those with no eating disorder symptoms (No ED). Groups were compared on measures of weight, depressive symptoms, and alexithymia. Results: Binge eating was frequently reported by women in this study (BED, 16.1%; BN, 4.6%; BE, 22.6%). BED women had significantly higher body mass index, greater highest weight ever, and more frequent weight cycling than the No ED group. BED women also reported more depressive symptoms than BE and No ED women, and were more alexithymic than the No ED group. BE women presented more frequent weigh cycling and were also more depressed and alexithymic than the No ED group. Discussion: BED is not uncommon in overweight Brazilian women, and similar to North American and European samples, it is associated with overweight and higher levels of psychopathology in this population.  相似文献   
86.
Influence of Sugars on in vitro Rooting and Acclimatization of Carob Tree   总被引:1,自引:1,他引:0  
Carob tree (Cerafoma siliqua L.) micropropagated shoots were rooted on half-strength Murashige and Skoog medium, supplemented with different types and concentrations of sugars, in order to determine the effects of sugar composition and concentration on in vitro rooting and in vivo establishment of the plantlets. Among the various sugars tested, the best rooting response was obtained with 145 mM sucrose, both in terms of rooting frequency and index of rooting. The use of filter-sterilized rather that autoclaved fructose increased root number and root length. Sugar treatment during rooting slightly influenced plantlet survival and growth during acclimatization. A reduction in the glucose concentration during rooting was beneficial for plantlet acclimatization.  相似文献   
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