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31.
Freeze-drying (FD) has been exhaustively tried in several mammalian species as an alternative technique to sperm cryopreservation, but few studies have been done in rabbits (Oryctolagus cuniculus). The main objective of this study was to compare the protective effect of various antioxidants added to EDTA medium on structural and functional components of FD rabbit spermatozoa and on their status of global DNA methylation. FD media used were composed of basic FD medium (10 mM Tris-HCl buffer and 50 mM NaCl) supplemented with either 50 mM EDTA alone (EDTA) or added with 105 µM of rosmarinic acid (RA, EDTA-RA) or 10 µM of melatonin (MLT, EDTA-MLT). The effect of each medium on the preservation of FD spermatozoon structure was evaluated with light and scanning electron microscopy (SEM). Global DNA methylation was quantified in all FD sperm samples as well as in fresh spermatozoa. Morphologically, fracture points were evidenced in the neck, mid and principal piece of the spermatozoon tail. No differences in spermatozoon fracture points were evidenced among FD treatments: intact spermatozoa were the largest (p < .01) category, whereas the most frequent (p < .01) injury was the neck fracture, resulting in tailless heads. At SEM, the head of spermatozoa showed a well-conserved shape and intact membrane in all treatments. DNA methylation status was the same in all FD treatments. In conclusion, supplementation of EDTA, EDTA-RA and EDTA-MLT during FD preserved rabbit sperm morphological integrity and methylation status as well. Therefore, the difficulty of getting viable offspring using FD semen is likely unrelated to the impact of the lyophilization process on DNA methylation and morphology of lyophilized spermatozoa.  相似文献   
32.
The use of plant extracts could be a useful alternative to synthetic fungicides in the management of rot fungi during postharvest handling of fruit and vegetables. The aim of this study was to assess the in vitro and in vivo activity of extracts obtained from nine wild edible herbaceous species (Borago officinalis, Orobanche crenata, Plantago coronopus, P. lanceolata, Sanguisorba minor, Silene vulgaris, Sonchus asper, Sonchus oleraceus, and Taraxacum officinale) against some important postharvest pathogens, i.e. Botrytis cinerea, Monilinia laxa, Penicillium digitatum, P. expansum, P. italicum, Aspergillus carbonarius, and A. niger. Phenolic composition of all extracts was evaluated by HPLC. Several derivatives of caffeic acid, of the flavones apigenin and luteolin, and of the flavonols kaempferol and quercetin, were identified. Extracts from S. minor and O. crenata showed the highest efficacy in all the trials. In particular, S. minor completely inhibited in vitro the conidial germination of M. laxa, P. digitatum, P. italicum, and A. niger and strongly reduced those of B. cinerea; O. crenata extract showed a lower but still significant reduction of conidial germination on all the tested fungi. Moreover, the extracts from both species were effective in reducing the germ tube elongation also when a slight inhibition of conidial germination was observed. In many cases, a dose effect was observed, with an increase of antifungal activity as the phenolic concentration increased. In trials performed on wounded fruit, S. minor extract completely inhibited brown rot on apricots and nectarines; O. crenata extract strongly reduced grey mould, brown rot, and green mould on table grapes, apricots and nectarines, and oranges, respectively. The inhibition efficacy of extracts was ascribed to the presence of some caffeic acid derivatives and/or flavonoids. HPLC phenolic analyses provided useful information to identify the possible active compounds.  相似文献   
33.
The control of contaminants in fertilizers and industrial by-products is fundamental to safe food production, and it requires low-cost, reliable test methods. The aim of this study was to evaluate the performance of the USEPA 3051a and alternative analytical methods [concentrated hydrochloric acid (HCl), 10 percent HCl, 10 percent sulfuric acid (H2SO4), and 50 mmol L?1 diethylenetriaminepentaacetic acid (DTPA)] for quantifying the levels of lead, cadmium, chromium, and nickel in zinc and/or copper sources. The sample digestions with concentrated HCl, H2SO4, and nitric acid (HNO3) (USEPA 3051a) were heated. Extraction without heating and stirring was employed in 10 percent HCl and 50 mmol L?1 DTPA methods. The Graybill’s modified F-test, t-test for mean error, and the linear correlation coefficient analysis were used to compare test method performance. Equivalent results to USEPA 3051a were found with the following methods: DTPA for the extraction of lead in zinc sources and concentrated HCl and H2SO4 for the extraction of cadmium and chromium in copper sources. However, the absolute values of cadmium, chromium, and nickel recovered by the use of H2SO4 were greater regardless of the source. The greater extraction of contaminants in the evaluated methods suggests that there is need to review the official method if the aim is to quantify the total levels of these elements in raw materials and mineral fertilizers.  相似文献   
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35.
Fusarium rot on melon fruits is a postharvest disease and its importance in Brazil is increasing since its first report in 1999. Initially this disease was attributed to the fungus Fusarium semitectum based on pathogen morphology. However, there is controversy regarding the aetiology of this disease because, in the current species concept based on phylogenetic analysis, F. semitectum is regarded as a synonym to different Fusarium species. With the objective of elucidating the disease aetiology in Northeast Brazil, Fusarium isolates were obtained from melon fruits showing rot symptoms in the main producing areas of the country. From the phylogenetic analyses of TEF1 and RPB2 gene sequences, the isolates were identified as belonging to two phylogenetic species of the Fusarium incarnatum-equiseti species complex (FIESC), one in the Incarnatum clade (Fusarium sulawense) and the other in the Equiseti clade, which corresponds to a new lineage. The newly identified lineage is close to Fusarium lacertarum. Isolates from the two species showed morphological characteristics typical of the Incarnatum and Equiseti clades, agreeing with the molecular identification, and were pathogenic when inoculated on melon fruits. This is the first report of F. sulawense on melon fruits. The data generated in this study are potentially useful for a better management of the fusarium rot on melon.  相似文献   
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37.
A noninvasive method for quantifying adrenal gland vascular patterns could be helpful for improving detection of adrenal gland disease in dogs. The purpose of this retrospective study was to compare the contrast‐enhanced ultrasound (CEUS) characteristics of adrenal glands in 18 dogs with pituitary‐dependent hyperadrenocorticism (PDH) vs. four clinically healthy dogs. Each dog received a bolus of the contrast agent (SonoVue®, 0.03 ml/kg of body weight) into the cephalic vein, immediately followed by a 5 ml saline flush. Dynamic contrast enhancement was analyzed using time–intensity curves in two regions of interest drawn manually in the caudal part of the adrenal cortex and medulla, respectively. In healthy dogs, contrast enhancement distribution was homogeneous and exhibited increased intensity from the medulla to the cortex. In the washout phase, there was a gradual and homogeneous decrease of enhancement of the adrenal gland. For all dogs with PDH, there was rapid, chaotic, and simultaneous contrast enhancement in both the medulla and cortex. Three distinct perfusion patterns were observed. Peak perfusion intensity was approximately twice as high (P < 0.05) in dogs with PDH compared with that of healthy dogs (28.90 ± 10.36 vs. 48.47 ± 15.28, respectively). In dogs with PDH, adrenal blood flow and blood volume values were approximately two‐ to fourfold (P < 0.05) greater than those of controls. Findings from the present study support the use of CEUS as a clinical tool for characterizing canine adrenal gland disease based on changes in vascular patterns.  相似文献   
38.
Peach lipid transfer protein (LTP) can cause severe allergic reactions to peach-allergic patients. It belongs to the nonspecific LTPs family, a class of proteins extremely resistant both to proteolytic digestion and to high temperatures. Food processing can either drop or increase the allergenicity, depending on the process and on the food. As far as peach-derived products (pulp, juice) are concerned, it has been previously shown how thermal treatment performed in an autoclave does not decrease LTP allergenicity. In this work, it was attempted to investigate whether sequential microwave and ultrasound processing could affect the allergenicity of peach juice. Incubation with specific anti-Pru p 3 serum showed how treating peach peel with microwave at 140 °C and with ultrasound does not eliminate Pru p 3 IgE binding properties. The application of MW/US protocol on peach pulp appeared to be insufficient for the reduction of IgE binding to Pru p 3.  相似文献   
39.
The causal agents of mango malformation disease in Brazil are a new Fusarium lineage in the Gibberella fujikuroi species complex and Fusarium sterilihyphosum; however information on the genetic and geographical diversity of these pathogens in Brazil is missing. Vegetative compatibility group (VCG) and amplified fragment length polymorphism (AFLP) analyses were used to measure the genetic diversity within these populations. Both techniques identified the same genetic groups. Six VCG and AFLP groups were identified amongst isolates of the new lineage from Brazil. FB-VCG 1/AFLP I was the most widespread group, found in seven of the 13 sites sampled. The second most frequent group was recovered from three sites. The remaining four groups were recovered from single-sites. We think that this lineage represents a genetically and geographically diverse indigenous population that reproduces clonally. In F. sterilihyphosum, group FS-VCG 1/AFLP VII was found at three sites in the southeast region of Brazil. FS-VCG 2/AFLP VIII contained isolates from South Africa but not from Brazil. Fusarium mangiferae isolates from India and South Africa formed one group, while isolates from Egypt and the USA formed a second group. F. sterilihyphosum at present is represented by a small population that might have been introduced only once into a restricted area. The clonal nature of the observed populations suggests that these fungi either occur naturally on indigenous hosts and have jumped to the introduced mango host (introduced in Brazil) or that they originated with mango and went through a severe population bottleneck when they were introduced to Brazil from India or Southeast Asia.  相似文献   
40.
Google Earth® provides free access to satellite images and has been used in several areas that require cartographic information. The present study assessed the inconsistencies between geo-referencing of livestock premises by GPS and the acquisition of geographic coordinates by remote sensing (RS) images provided by Google Earth® in the Brazilian states of Bahia, Distrito Federal, Minas Gerais and Parana. The overall mean and standard deviation of the distances in the study were 30.98 ± 19.89 m. The mean distance differences between the two techniques were, for these states, 37.20 ± 19.75 m, 28.38 ± 17.38 m, 31.61 ± 15.72 m, 28.43 ± 24.30 m, respectively. Despite the fact that there is variation between the geo-referencing points using GPS and RS, geographical localization of health inspections should be useful as long as the errors between the results of the two methodologies are considered.  相似文献   
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