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191.
The genus Passiflora L. has more than 400 species, most of which occur natively in tropical and subtropical regions of South America. The fruit of Passiflora tenuifila Killip, one of the native species of Brazil, has great potential for commercial use by pharmaceutical and cosmetic industries, due to its high content of phenolic compounds, which are natural antioxidants. The study was conducted in two areas located in Tocantins and in the Federal District, Brazil. The presence of globose lumps and thickening of the stems on plants of Pa. tenuifila was observed on plants in these areas. Injured samples taken from both locations were analyzed and showed the presence of larvae and pupae of a Curculionidae, which completed their life cycle in the laboratory. The adults were identified as Philonis crucifer (Brèthes) (Coleoptera: Curculionidae). In Tocantins, 100% of the plants in the trial area were infested, while in the Federal District trial the incidence of infestation was 20.3%. This is the first report of an insect on Pa. tenuifila, indicating the need to develop management strategies for this pest to be applied in commercial crops of this Passiflora species.  相似文献   
192.
Tetrodotoxin is a potent low weight marine toxin found in warm waters, especially of the Indian and Pacific Oceans. Intoxications are usually linked to the consumption of the puffer fish, although TTX was already detected in several different edible taxa. Benthic organisms such as mollusks and echinoderms, with different feeding habits, were collected monthly along the Portuguese coast from the summer of 2009 until the end of 2010. The extraction and analysis techniques were optimized and TTX and some analogues were detected for the first time in two intertidal gastropod species-Gibbula umbilicalis and Monodonta lineata by LC-MS/MS and UPLC-MS/MS. Although the levels are low, these findings suggest that monitoring of TTX and analogues in North Atlantic species should be implemented so as to detect potentially new toxin vectors and seasonal and/or geographical patterns.  相似文献   
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In our research we focused our attention on the effect of the immune stress induced by bacterial endotoxin–lipopolysaccharide (LPS) on the hypothalamic–pituitary–gonadal axis (HPG) at the pituitary level. We examined the effect of intravenous (i.v.) LPS injection on luteinizing hormone (LH) and follicle‐stimulating hormone (FSH) release from the anterior pituitary gland (AP) in anestrous ewes. The effect of endotoxin on prolactin and cortisol circulating levels was also determined. We also researched the effect of immune challenge on the previously mentioned pituitary hormones and their receptors genes expression in the AP. Our results demonstrate that i.v. LPS injection decreased the plasma concentration of LH (23%; p < 0.05) and stimulates cortisol (245%; p < 0.05) and prolactin (60%; p < 0.05) release but has no significant effect on the FSH release assayed during 6 h after LPS treatment in comparison with the control levels. The LPS administration affected the genes expression of gonadotropins’β‐subunits, prolactin and their receptors in the AP. Endotoxin injection significantly decreased the LHβ and LH receptor (LHR) gene expression (60%, 64%; p < 0.01 respectively), increased the amount of mRNA encoding FSHβ, FSH receptor (FSHR) (124%, 0.05; 166%, p < 0.01; respectively), prolactin and prolactin receptor (PRLR) (50%, 47%, p < 0.01; respectively). The presented, results suggest that immune stress is a powerful modulator of the HPG axis at the pituitary level. The changes in LH secretion could be an effect of the processes occurring in the hypothalamus. However, the direct effect of immune mediators, prolactin, cortisol and other components of the hypothalamic pituitary–adrenal (HPA) axis on the activity of gonadotropes has to be considered as well. Those molecules could affect LH synthesis directly through a modulation at all stages of LHβ secretion as well as indirectly influencing the GnRHR expression and leading to reduced pituitary responsiveness to GnRH stimulation.  相似文献   
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Brazilian savanna constitutes a valuable ecoregion that contributes to the supply of fruit known worldwide for its nutritional value and peculiar flavors. Among them, the Marolo (Annona crassiflora Mart.) fruit is known for its use in folk medicine. In order to establish the safety of Marolo for human consumption, this study evaluated the following: the chemical composition of Marolo pulp; its mutagenic and antimutagenic activities using micronucleus test; and the oxidative stress induced in the livers of mice fed a diet containing 1%, 10% or 20% pulp. It was observed that the chemical composition of marolo pulp was similar to that of common fruit; nevertheless, its lipidic content and energetic values were higher. In the mice fed experimental diets, the biochemical parameters of the blood serum showed normal levels of glucose, triglycerides, and cholesterol. The micronucleus test indicated neither mutagenic nor antimutagenic effects of Marolo consumption on bone marrow cells but showed potentialization of cyclophosphamide (CP). The oxidative stress levels observed indicated that CP was not exerting a great influence on the induction of reactive oxygen species. As the whole fruit is a complex matrix, the interactions between its components could be responsible for its negative and positive biological effects.  相似文献   
199.
Senegalese sole (Solea senegalensis, Kaup) is a promising flatfish species in aquaculture. However, skeletal anomalies are still a great concern in sole farming. Investigation of this issue is crucial to improving larval quality and optimizing production. The aim of this study was to thoroughly assess anomalies in the rachis of reared sole at early developmental stages. Sole (n = 507) were sampled at 31 or 32 days after hatching (dah). The specimens were stained with alcian blue and alizarin red and evaluated for the detection of vertebral deformities. Most fish presented 9:34:3 vertebrae in abdominal, caudal and caudal complex regions, respectively. Remarkably, all specimens showed at least one spinal anomaly. Alterations of neural/haemal elements, as well as deformities of hypurals, parhypural and epural, were recurrent. Vertebral body anomalies and/or vertebral column deviations were identified in 52% of the individuals. Vertebral deformations and fusions were common, especially in caudal complex. ‘Minor’ anomalies were predominant, and some of the detected disorders might be a result of non‐/low‐pathological processes. These results contribute a new insight into the main skeletal anomalies affecting cultured sole larvae. Further research is required to determine their impact on fish welfare and external appearances at commercial stages.  相似文献   
200.
Knowledge of evapotranspiration (ET) and water-use efficiency (WUE) is essential in crops management mainly in arid and semiarid regions where water resources are scarce for irrigation. Field experiments were conducted at a commercial farm to obtain the WUE and ET of mango orchard growth in a semiarid environment of northeastern region of Brazil. Measurements were performed within a randomly selected experimental plot with the spacing of 10 m × 5 m between rows and plants. Soil water balance method was used to obtain the mango orchard evapotranspiration while the Penman–Monteith method (FAO/56) was used for determination reference evapotranspiration (ETo). Soil water content was determined by six tensiometer sets installed at 0.20 m layer intervals from the soil surface down to 1.20 m soil depth. The experimental plot was irrigated with a sprinkler irrigation system based on four irrigation levels (T1 = 70%, T2 = 80%, T3 = 90% and T4 = 100% of ETo. Results showed that ET and WUE are strongly influenced by soil water availability. Mango yield varied from a minimum value of 28.06 ton/ha in treatment T4 to a maximum value of 31.06 ton/ha in treatment T3. Such difference was found to be statistically significant (P < 0.05) by Tukey's test. Results also indicated that WUE values based on irrigation and evapotranspiration were maximum and minimum for low (treatment T1) and high (treatment T4) water levels, respectively.  相似文献   
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