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21.
Glycerol Tolerance of IHHN Virus of Penaeid Shrimp 总被引:1,自引:0,他引:1
22.
Waap H Cardoso R Marcelino E Malta J Cortes H Leitão A 《Veterinary parasitology》2011,178(3-4):217-222
Bovine besnoitiosis is caused by Besnoitia besnoiti, an obligate intracellular apicomplexan parasite. Affected animals present cutaneous and systemic manifestations and the disease may lead to considerable economic losses. Although generally associated to tropical and subtropical areas, bovine besnoitiosis is now considered an emergent disease in Europe, due to the increasing number of new cases and apparent geographical expansion. In this study we evaluated the performance of a modified agglutination test (B-MAT) in the serodiagnosis of bovine besnoitiosis in comparison to the indirect immunofluorescent-antibody test (IFAT). To establish optimal protocol conditions we used bovine sera with a known infection status for B. besnoiti infection. Positive animals (n=36) presented B. besnoiti dermal cysts and anti-B. besnoiti specific antibodies, as determined by the indirect immunofluorescence test (IFAT). Negative animals (n=103) were from non-endemic areas in Portugal and negative by the IFAT. From here, we evaluated the sensitivity and specificity of the B-MAT relative to the IFAT with a panel of sera from herds with history of bovine besnoitiosis in Portugal, Spain and France (n=402), using three serum dilutions (1:80, 1:160, 1:320). Considering the positive cut-off at 1:160 serum dilution, the B-MAT showed an almost perfect test agreement with the IFAT; (κ=0.968; 95% CI: 0.941-0.996) with a relative sensitivity of 97.2% (95% CI: 94.1-100%) and a relative specificity of 99.3% (95% CI: 98.4-100%). As a simple and inexpensive technique the B-MAT represents a valuable tool for the diagnosis and study of the epidemiology of bovine besnoitiosis. 相似文献
23.
Characterization of commercial kava-kava herbal drug and herbal drug preparations by means of nuclear magnetic resonance spectroscopy 总被引:1,自引:0,他引:1
Bilia AR Bergonzi MC Lazari D Vincieri FF 《Journal of agricultural and food chemistry》2002,50(18):5016-5025
The efficiency of one- and two-dimensional NMR experiments in characterizing the content of the constituents of both herbal drugs and herbal drug preparations is demonstrated for kava-kava. These experiments directly detect active constituents represented by kavalactones in both a finely powdered herbal drug and a commercial extract. In addition, NMR spectroscopy can detect all other compounds present in the extract. As previously evidenced, NMR experiments can represent a generally applicable technique for rapid screening and are a complement to the classical analytical techniques such as high-performance thin-layer chromatography, high-performance liquid chromatography, capillary gas chromatography, and electrophoresis. These experiments can be considered a very simple and fast analytical method to obtain a fingerprint of the herbal drugs and their preparations, and to quantify the content of the active principles of the extract. 相似文献
24.
Fratianni A Irano M Panfili G Acquistucci R 《Journal of agricultural and food chemistry》2005,53(7):2373-2378
Color is an important parameter involved in the definition of semolina and pasta quality. This character is mainly due to natural pigments (carotenoids) that are present at different levels in cereals and cereal products, due to botanical origin, growing conditions, distribution in the kernel, and technological processes. In food industries, color measurements are usually performed by means of automatic instruments that are rapid and safe, as alternatives to the chemical extraction methods. In this study, automatic measurements (CIE, color-space system L, a, b), water-saturated butanol (WSB), and HPLC determinations have been applied to evaluate the carotenoid content in whole meals and respective semolina samples produced from wheat cultivated in the years 2001 and 2002. In whole meals, total carotenoids, determined by HPLC, were about 3.0 microg/g (2001) and 3.5 microg/g (2002) calculated on dry weight (dw) and about 3.0 and 3.2 microg/g dw in corresponding semolina samples. The b values for the same period were 19.78 and 15.75, respectively, in raw materials and 20.03-21.67 in semolina. Results have confirmed lutein and beta-carotene as the main components mainly responsible for the yellow color in wheat grains. The ability of the index b to express natural dyeing was dependent on sample characteristics as demonstrated by the relationships found between this index and pigments, although the best correlation resulted between HPLC and WSB. 相似文献
25.
Galati EM Mondello MR Giuffrida D Dugo G Miceli N Pergolizzi S Taviano MF 《Journal of agricultural and food chemistry》2003,51(17):4903-4908
The juice of whole fruits of Sicilian cultivars of prickly pear (Opuntia ficus indica (L.) Mill.) was investigated, and the contents of ascorbic acid, total polyphenols, and flavonoids were determined. In the juice, ferulic acid was the chief derivative of hydroxycinnamic acid and the mean concentration of total phenolic compounds was 746 microg/mL. The flavonoid fraction, analyzed by high-performance liquid chromatography-diode array detection, consisted of rutin and isorhamnetin derivatives. The juice showed antioxidant activity in the DPPH(*) test, probably due to the phenolic compounds that are effective radical scavengers. The preventive administration of the juice inhibited the ulcerogenic activity of ethanol in rat. Light microscopy observations showed an increase in mucus production and the restoration of the normal mucosal architecture. The juice is nutritionally interesting, and its dietary intake could provide protection against oxidative damage. 相似文献
26.
Regina Skuodiene Kazimieras Katutis Rita Nekrosiene Regina Repsiene Danute Karcauskiene 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(8):653-663
ABSTRACTThe research has been conducted for four years in five phytocenoses affected by the processes of naturalization. Two of them are located in non-flooded, relatively abandoned meadows and the remaining - flooded meadows in different parts of the Nemunas delta (Western Lithuania). The aim of the research was to estimate the influence of ecological conditions (humidity regimes, soil agrochemical parameters) on semi-natural meadow productivity. Humidity regimes and nitrogen amount in the soil influenced dry matter (DM) yield of meadow phytocesosis. The biggest DM yield (8.64 ± 0.77 t ha-1) was found in flooded meadow in the central part of the Nemunas delta in Terric Histosol (HSs) soil, which had moderate acidity and was rich in nitrogen. The economic value depended on the prevailing plant species and was the highest in non-flooded meadows. Botanical composition and plant species number depended on agrochemical characteristics of the soil and management activities: the greatest plant species diversity and the best plant population stability were established in flooded meadow in the riverside part of the Nemunas delta behind a levee in soil rich in phosphorus and potassium and low acidity. A similar number of plant species and similar ecological stability parameters were found in non-flooded meadow, whose soil was low in nutrients, but there was intensified farming. 相似文献
27.
28.
Rita M. De Miccolis Angelini Wassim Habib Caterina Rotolo Stefania Pollastro Francesco Faretra 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(2):185-199
Resistance to the fungicide boscalid in laboratory mutants of Botryotinia fuckeliana (Botrytis cinerea) was investigated. The baseline sensitivity to boscalid was evaluated in terms of colony growth (EC50 = 0.3–3 μg ml−1; MIC = 10–30 μg ml−1) and conidial germination (EC50 = 0.03–0.1 μg ml−1; MIC = 1–3 μg ml−1) tests. Mutants were selected in vitro from wild-type strains of the fungus on a fungicide-amended medium containing acetate as a carbon source. Mutants showed
two different levels of resistance to boscalid, distinguishable through the conidial germination tests: low (EC50 ∼ 0.3 μg ml−1, ranging from 0.03 to 1 μg ml−1; MIC > 100 μg ml−1) and high (EC50 > 100 μg ml−1) resistance. Analysis of meiotic progeny from crosses between resistant mutants and sensitive reference strains showed that
resistant phenotypes were due to mutations in single major gene(s) inherited in a Mendelian fashion, and linked with both
the Daf1 and Mbc1 genes, responsible for resistance to dicarboximide and benzimidazole fungicides, respectively. Gene sequence analysis of
the four sub-units of the boscalid-target protein, the succinate dehydrogenase enzyme, revealed that single or double point
mutations in the highly conserved regions of the iron-sulphur protein (Ip) gene were associated with resistance. Mutations
resulted in proline to leucine or phenylalanine replacements at position 225 (P225L or P225F) in high resistant mutants, and
in a histidine to tyrosine replacement at position 272 (H272Y) in low resistant mutants. Sequences of the flavoprotein and
the two transmembrane sub-units of succinate dehydrogenase were never affected. 相似文献
29.
Rita?MusettiEmail author Luigi?Sanità?di Toppi Marta?Martini Francesca?Ferrini Alberto?Loschi Maria?Augusta?Favali Ruggero?Osler 《European journal of plant pathology / European Foundation for Plant Pathology》2005,112(1):53-61
Hydrogen peroxide (H2O2) localization and roles of peroxidases, malondialdehyde and reduced glutathione were compared in leaves of apricot (Prunus armeniaca) plants asymptomatic, European Stone Fruits Yellows (ESFY)-symptomatic and recovered. Nested PCR analysis revealed that Candidatus Phytoplasma prunorum, is present in asymptomatic, symptomatic and recovered apricot trees, confirming previous observations on this species, in which recovery does not seem to be related to the disappearance of phytoplasma from the plant.H2O2was detected cytochemically by its reaction with cerium chloride, which produces electron-dense deposits of cerium perhydroxides. H2O2was present in the plasmalemma of the phloem cells of recovered apricot plant leaves, but not in the asymptomatic or symptomatic material. Furthermore, by labelling apricot leaf tissues with diaminobenzidine DAB, no differences were found in the localization of peroxidases.Protein content in asymptomatic, symptomatic and recovered leaves was not significantly different from one another. In contrast, guaiacol peroxidase activity had the following trend: symptomatic > recovered > asymptomatic, whereas reduced glutathione content followed the opposite trend: asymptomatic > recovered > symptomatic. Moreover, no differences were observed in malondialdehyde concentrations between asymptomatic, symptomatic and recovered leaves. The overall results suggest that H2O2 and related metabolites and enzymes appear to be involved in lessening both pathogen virulence and disease symptom expression in ESFY-infected apricot plants. 相似文献
30.
E.F Kaleta O Siegmann Rita Jank-Ladwig G Glünder 《Comparative immunology, microbiology and infectious diseases》1979,2(4):485-496
From each of two lentogenic Newcastle disease virus (NDV) strains of the type LaSota and Hitchner B1 a virulent subpopulation could be obtained. The two subpopulations were—in comparison to the two parent viruses—more resistant to the lipid solvent chloroform and more stable against thermal degradation. Also, the glycoproteins haemagglutinin and F (fusion) were more stable against thermal inactivation. Electron microscopic observations revealed in terms of size and morphology all of the characteristics of NDV. Both subpopulations possessed, however, the same elution kinetics as their respective parent strains. The intracerebral and intravenous pathogenicity indices as well as the mean death times of the two subpopulations allow to classify these viruses as virulent Newcastle disease viruses. 相似文献