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51.
During the past decades, the huge use of pesticides caused several environmental problems, so research investigations moved to find a series of compounds with selective toxicity, of a biodegradable and environment-friendly nature, maintaining a positive action in crop and stored products protection. In this perspective, interesting results in the control of pests and fungal pathogens were obtained using essential oils, which are compounds produced by many species of plants as secondary metabolites. The purpose of this research was to evaluate the fumigant activity of five Citrus essential oils against the confused flour beetle Tribolium confusum Du Val, planning a possible employment in the mill industry. The fumigant effectiveness was evaluated 24, 48, 72 hours and 7 days after the start of exposure and each essential oil was analyzed by means of GC and GC/MS. Further evaluations about the toxicity of these compounds were made by partially filling the glass vials with food matrix, in order to assess the possible interference of this matter on the active compounds. The data obtained indicated that, at a low level of fumigant concentration, essential oils can effectively control stored product pests; in the presence of debris, like flour, the efficacy decreased. Plant extracts caused also increased mortality levels after the end of fumigation. The results obtained from this experimentation confirm the efficacy of essential oils in pest control and, in particular, against stored product pests.  相似文献   
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53.
Tomato is challenged by several pathogens which cause loss of production. One such pathogen is the oomycete Phytophthora infestans which is able to attack all the aerial parts of the plant. Although a wide range of resistance sources are available, genetic control of this disease is not yet successful. Pyramiding R-genes through genetic transformation could be a straightforward way to produce tomato and potato lines carrying durable resistance to P. infestans. In this work the R1 potato gene was transferred into tomato lines. The tomato transgenic lines were analyzed by using q-RT-PCR and progeny segregation to determine the gene copy number. To test the hypothesis that R1 represents a specifically regulated R-gene, transgenic tomato plants were inoculated with P. infestans isolate 88133 and IPO. All the plants containing the R1 gene were resistant to the late blight isolate IPO-0 and susceptible to isolate 88133. These results provide evidence for specific activation of the R1 gene during pathogen challenge. Furthermore, evidence for enhancement of PR-1 gene expression during P. infestans resistance response was obtained.  相似文献   
54.
Cryopreservation of ovarian cortex has important implications in the preservation of fertility and biodiversity in animal species. Slow freezing of cat ovarian tissue resulted in the preservation of follicular morphology and in the follicular development after xenografting. Vitrification has been recently applied to ovarian tissues of different species, but no information is available on the effect of this method on feline ovarian cortex. Moreover, meiotic competence of fully grown oocytes isolated from cryopreserved tissue has not been reported. The aim of this study was to evaluate the effect of vitrification of feline ovarian cortex on follicular morphology and oocyte integrity, as well as meiotic competence. A total of 352 fragments (1.5-2 mm(3) ) were obtained from ovarian cortical tissues: 176 were vitrified and 176 were used fresh as control. Histological evaluation of fresh and vitrified fragments showed intact follicles after cryopreservation procedures with no statistically significant destructive effect from primordial to antral follicles. After IVM, oocytes collected from vitrified ovarian fragment showed a higher proportion of gametes arrested at germinal vesicle (GV) stage compared to those isolated from fresh control tissue (33.8% vs 2.9%; p < 0.001). However, oocytes isolated from vitrified tissues were able to resume meiosis, albeit at lower rate than those collected from fresh tissues (39.8% vs 85.9%; p < 0.00001). Vitrification induced changes in the organization of cytoskeletal elements (actin microfilaments and microtubules) of oocytes, but significantly only for actin network (p < 0.001). Finally, chromatin configuration within the GV was not affected by the cryopreservation procedure. Our study demonstrated that vitrification preserves the integrity of ovarian follicles and that oocytes retrieved from cryopreserved tissue maintain the capability of resuming meiosis. To our knowledge, this has not previously been reported in the cat.  相似文献   
55.
Anellovirus is a recently created, floating genus of viruses. Torque teno virus (TTV), the type species in the genus, was first discovered in a human patient with a post-transfusion hepatitis of unknown aetiology. Recently, TTV genetically related to but distinct from those discovered in humans have also been found in animals, including pigs. The aims of this study were to estimate the prevalence of swine TTV in Italian pig herds and some risk factors possibly associated with this infection. Serum samples from 179 healthy pigs from 10 farms located in north-central Italy were tested by polymerase chain reaction for the presence of swine TTV DNA. Viral DNA was found in the sera of 43 pigs (24.0%), coming from eight of the 10 farms examined. Prevalence was significantly higher in finishing herds (40.1%) than in farrow-to-finish herds (11.0%) and did not depend on the size of the herd. Within the finishing herds the prevalence was significantly higher in weaners (57.4%) than in fatteners (22.9%), but this difference was not observed in farrow-to-finish herds. No relationship was observed between the prevalence of swine TTV and the implementation of some general hygiene practices and biosecurity procedures within the herds.  相似文献   
56.
Salmonella Typhimurium (including S.Typhimurium 1,4,[5],12:i-) and other enteric pathogens cause acute infection in pigs during the weaning stage, often evolving into chronic infections responsible for the introduction of zoonotic bacteria into the slaughterhouse and thus determining carcass contamination. In addition to being zoonotic hazards, these pathogens are responsible for economic losses in affected farms. Traditionally, antibiotic treatments have been largely administered in order to reduce the infection burden but it favored, as a direct consequence, an increase in the number of multi-drug resistance strains. In order to overcome antibiotic-resistance concerns, new alternative control strategies should be developed. In this context, a blend of organic acids, phytochemicals and a permeabilizing complex, administered in feed (Group A - 459 piglets) or water (Group B – 458 piglets), was tested in field conditions for its capability of reducing Salmonella-infection in weaned piglets of an endemic farm. Data recorded were compared to results of a control group (Group C - 456 piglets). Zootechnical parameters were recorded in all animals, while microbiological, serological and PCR analyses were conducted in 15 piglets for each group. Results demonstrated that additive administered in feed improved animal weight gain (better average daily gain [A.D.G.] and increment), and rapidly reduced Salmonella-shedding in feces. Administration of additive in feed gave better results than in water.  相似文献   
57.
Aminoethylcysteine ketimine decarboxylated dimer (simply named dimer) is a natural sulfur-containing tricyclic compound detected, until now, in human urine, bovine cerebellum, and human plasma. Recently, the antioxidant properties of this compound have been demonstrated. In this investigation, the presence of aminoethylcysteine ketimine decarboxylated dimer was identified in garlic, spinach, tomato, asparagus, aubergine, onion, pepper, and courgette. Identification of this compound in dietary vegetables was performed using gas chromatography, high-performance liquid chromatography, and gas chromatography-mass spectrometry. Results from GC analysis range in the order of 10(-4) micromol of dimer/g for all the tested vegetables. These results and the lack of a demonstrated biosynthetic pathway in humans might account for a dietary supply of this molecule.  相似文献   
58.
Antimicrobial peptides (AMPs) are found widespread in nature and possess antimicrobial and immunomodulatory activities. Due to their multifunctional properties, these peptides are a focus of growing body of interest and have been characterized in several fish species. Due to their similarities in amino-acid composition and amphipathic design, it has been suggested that neuropeptides may be directly involved in the innate immune response against pathogen intruders. In this review, we report the molecular characterization of the fish-specific AMP piscidin1, the production of an antibody raised against this peptide and the immunohistochemical identification of this peptide and enkephalins in the neuroepithelial cells (NECs) in the gill of several teleost fish species living in different habitats. In spite of the abundant literature on Piscidin1, the biological role of this peptide in fish visceral organs remains poorly explored, as well as the role of the neuropeptides in neuroimmune interaction in fish. The NECs, by their role as sensors of hypoxia changes in the external environments, in combination with their endocrine nature and secretion of immunomodulatory substances would influence various types of immune cells that contain piscidin, such as mast cells and eosinophils, both showing interaction with the nervous system. The discovery of piscidins in the gill and skin, their diversity and their role in the regulation of immune response will lead to better selection of these immunomodulatory molecules as drug targets to retain antimicrobial barrier function and for aquaculture therapy in the future.  相似文献   
59.
This paper refers on the yields and productive aspects of mineral and foliar nutrition of globe artichoke plants (cv. ‘Opal’ and ‘Madrigal’). Marketable yields were investigated in response to different nitrogen rates and foliar applications of biostimulating products. Field experiments were conducted over two seasons on an alluvial salty-clay soil in sub-humid climate conditions. Analyzed traits differed between years because of the age of plants while the lowest nitrogen rate and foliar spraying of biostimulants influenced significantly head weight, dry matter, and Soil Plant Analysis Division (SPAD) index. Biostimulants induced longer cultural cycle and heads lighter in weight. Cultivar ‘Madrigal’ was most productive than ‘Opal’, both in number (26.28% higher) and in weight (28.51%) of total heads. The two-year investigation showed that the synergic action was effective in improving some of the investigated productive traits of globe artichoke.  相似文献   
60.
BackgroundThe blood‐brain barrier (BBB), which separates the intravascular and neuropil compartments, characterizes the vascular bed of the brain and is essential for its proper function. Recent advances in imaging techniques have driven the development of methods for quantitative assessment of BBB permeability.Hypothesis/ObjectivesPermeability of the BBB can be assessed quantitatively in dogs with meningoencephalitis of unknown origin (MUO) and its status is associated with the occurrence of seizures.AnimalsForty dogs with MUO and 12 dogs without MUO.MethodsRetrospective, prospective cohort study. Both dynamic contrast enhancement (DCE) and subtraction enhancement analysis (SEA) methods were used to evaluate of BBB permeability in affected (DCE, n = 8; SEA, n = 32) and control dogs (DCE, n = 6; SEA, n = 6). Association between BBB dysfunction (BBBD) score and clinical characteristics was examined. In brain regions where BBBD was identified by DCE or SEA magnetic resonance imaging (MRI) analysis, immunofluorescent staining for albumin, glial fibrillary acidic protein, ionized calcium binding adaptor molecule, and phosphorylated mothers against decapentaplegic homolog 2 were performed to detect albumin extravasation, reactive astrocytes, activated microglia, and transforming growth factor beta signaling, respectively.ResultsDogs with BBBD had significantly higher seizure prevalence (72% vs 19%; P = .01) when compared to MUO dogs with no BBBD. The addition of SEA to routine MRI evaluation increased the identification rate of brain pathology in dogs with MUO from 50% to 72%.Conclusions and Clinical ImportanceImaging‐based assessment of BBB integrity has the potential to predict risk of seizures in dogs with MUO.  相似文献   
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