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61.
Giardia duodenalis and Cryptosporidium spp. are intestinal protozoan parasites that infect a wide range of host species, including humans. Molecular characterization of these parasites has demonstrated that a number of genotypes and species are common to both humans and animals, and that zoonotic transmission may occur. Numerous studies have reported a high prevalence of G. duodenalis and Cryptosporidium spp. in cattle, particularly calves, and these animals are frequently associated with zoonotic transmission. In the present study, a total of 143 faecal samples from adults, heifers and calves were collected from two dairy cattle farms in eastern Ontario, Canada. The prevalence and molecular characteristics of G. duodenalis and Cryptosporidium spp. in these animals were determined in order to investigate the potential for transmission between cattle and humans in this region. Following DNA extractions from faecal samples, nested-PCR protocols were used to amplify fragments of the 16S rRNA gene and the heat-shock protein 70 (HSP-70) gene for determining the prevalence of G. duodenalis and Cryptosporidium spp. infections, respectively. Genotypes of G. duodenalis, and species of Cryptosporidium, were determined by means of DNA sequencing of amplicons, and subsequent sequence alignment. Cattle on both farms showed a high prevalence of G. duodenalis (42.0%) and Cryptosporidium spp. (27.3%). G. duodenalis infections were more prevalent in calves and heifers than in adults, and Cryptosporidium spp. infections were only observed in calves and heifers. The zoonotic genotype, G. duodenalis Assemblage B was isolated from 24.5% of the cattle tested, while G. duodenalis Assemblage E was found in 17.5% of the cattle tested. The overall prevalence of the zoonotic species Cryptosporidium parvum in the animals tested was found to be 21.7%, while only 1.4% were infected with C. bovis. These findings suggest that there is a potential risk of zoonotic and/or zooanthroponotic transmission of G. duodenalis and C. parvum infections between cattle and humans in eastern Ontario, likely by means of contaminated water or food, or through direct faecal-oral transmission in the case of farmers and veterinary staff. 相似文献
62.
Crude ethanol extracts from different tissues of Betula alleghaniensis: wood, inner and outer bark, foliage, and twigs were evaluated for their nitric oxide (NO)-radical scavenging activities and inhibitory effects on the production of NO in LPS/INFγ-stimulated RAW 264.7 macrophages. As a renewed interest in plant-derived drugs has led to an increased need for efficient extraction methods, ultrasonic-assisted extraction (UAE) was investigated and compared with conventional maceration. The lower energy consumption by the UAE process compared to maceration determined in our study qualifies also this extraction as an environmentally friendly process. Our results indicate that the foliage extract has the most potent radical scavenging capacity while wood and twigs extracts exert the highest inhibitory effects on the production of NO in LPS/INFγ-stimulated RAW 264.7 macrophages. Extracts obtained by UAE present lower cytotoxic activity on RAW cells. Our results also demonstrate that ultrasounds help to selectively extract the bioactive molecules from foliage, twigs and wood, which inhibit the production of NO by macrophages. The highest total phenol content has been determined for the inner bark extracts and the flavonoids are the major phenolics present in foliage extracts. Poor correlations determined between the total phenols and radical scavenging capacity of the extracts indicates to the synergistic or antagonist effects of molecules present, various polyphenols and triterpenes being identified in the extracts studied in this research. 相似文献
63.
Katarina Šavikin Gordana Zdunić Teodora Janković Slavoljub Tasić Nebojša Menković Tatjana Stević Boban Đorđević 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(3):212-217
Chemical composition and the effects of domestic processing and storage were studied in organically cultivated or wild growing
berries, harvested in certificated area in Serbia. The total phenolics content in fresh berries ranged from 380 to 1660 mg
GAE/100 g. The phenolic content decreased during the processing to jams, and storage in almost all samples, except in black
currant. Among fresh berries, the highest amount of total anthocyanins was found in bilberry (0.61 ± 0.03 %). Processing and
storage caused decrease in anthocyanin content. The most ubiquitous anthocyanin aglycone was found to be cyanidin. Ellagic
acid was detected in fresh and frozen black raspberries and related jams, and its content increases during thermal processing
to jam. Among fresh berries, bilberry showed the strongest DPPH radical scavenging activity with an IC50 value of 0.82 mg/ml. However, frozen as well as processed berries in our study still showed comparable high values of radical
scavenging activity. After 9 months of storage all investigated jams were microbiologicaly correct. Regardless of the losses
in the amount of total phenolics, total anthocyanins and radical scavenging activity, frozen berries and related jams are
still excellent sources of nutritional substances with antioxidant potential. 相似文献
64.
Ana??ari? Sandra?Sobo?anec Tihomir?BalogEmail author Borka?Ku?i? Vi?nja??verko Verica?Dragovi?-Uzelac Branka?Levaj Zrinka??osi? ?eljka?Ma?ak ?afranko Tatjana?Marotti 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(4):231-237
The present investigation tested the in vivo antioxidant efficacy (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase; Gpx), lipid peroxidation (LPO) and
anti-inflammatory properties (cyclooxygenase-2; COX-2) of sour cherry juices obtained from an autochthonous cultivar (Prunus cerasus cv. Maraska) that is grown in coastal parts of Croatia. Antioxidant potential was tested in mouse tissue (blood, liver, and
brain), LPO (liver, brain) and anti-inflammatory properties in glycogen elicited macrophages. Additionally, the concentration
of cyanidin-3-glucoside, cyanidin-3-rutinoside, pelargonidin-3-glucoside, pelargonidin-3-rutinoside and total anthocyanins
present in Prunus cerasus cv. Maraska cherry juice was determined. Mice were randomly divided into a control group (fed with commercial food pellets)
and 2 experimental groups (fed with commercial food pellets with 10% or 50% of cherry juice added). Among the anthocyanins,
the cyanidin-3-glucoside was present in the highest concentration. These results show antioxidant action of cherry juice through
increased SOD (liver, blood) and Gpx (liver) activity and decreased LPO concentration. The study highlights cherry juice as
a potent COX-2 inhibitor and antioxidant in the liver and blood of mice, but not in the brain. Thus, according to our study,
Prunus cerasus cv. Maraska cherry juice might potentially be used as an antioxidant and anti-inflammatory product with beneficial health-promoting
properties. 相似文献
65.
Nika Veronovski Andreja Rudolf Majda Sfiligoj Smole Tatjana Kreže Jelka Geršak 《Fibers and Polymers》2009,10(4):551-556
Self-cleaning surfaces based on photocatalysis are an extremely promising nano-technological field of extensive research and
development. Recently comprehensive research work has been performed to evaluate the optical, photocatalytic and antimicrobial
properties of TiO2 nano-particles and composites thereof. The aim of this study was to obtain self-cleaning properties for regenerate cellulose
surfaces by nano-modification, using TiO2 nano-coating and to define the impact of the modification on fabrics end-use properties. Two different modified fabrics with
self-cleaning effect were prepared and analysed, i.e. the modification efficiency was determined. In addition, the influence
of fibre modification on several textile properties was determined. However, a soft handle, good appearance and some other
surface properties accompanied by appropriate mechanical properties represent the basis for a high quality fabric therefore
the influence of the modification procedure on textiles handle was studied. 相似文献
66.
Ludmila Limantseva Nina Mironenko Oleg Shuvalov Olga Antonova Alexandr Khiutti Lubov Novikova Olga Afanasenko David Spooner Tatjana Gavrilenko 《Plant Breeding》2014,133(5):660-665
Potato cyst nematodes (PCN) collected in six localities in the Leningrad region of North West Russia were identified as Globodera rostochiensis pathotype Ro1 and were used for subsequent resistance tests. Seventy‐nine accessions of cultivated and closely related wild potato species from the VIR collection in Russia were screened on resistance to G. rostochiensis pathotype Ro1 and on the presence of molecular markers for H1 and Gro1‐4 resistance genes. No associations were detected between the resistance level of diploid and tetraploid Andean and tetraploid Chilean potato landraces (indigenous cultivars) and their related wild species and their geographical distribution or presence of PCR‐based markers that are associated with the H1 and Gro1‐4 genes. At the same time, all susceptible genotypes lacked such markers. New sources of resistance were found and could be used in breeding. 相似文献
67.
A simple and accurate flow-through system was developed for toxicity evaluation of biodegradable substances, wastewaters, and surface waters. The chronic toxicity of phenol to the daphnid Daphnia magna was studied during a 21 d exposure period, first using a semi-static and later a flow-through test. The flow- through system was advantageous especially when lower concentrations of phenol were examined. Its use provided a constant concentration of phenol in all tested samples. Exposure to phenol showed a similar influence on both survival and reproduction of daphnids; the IC25 value was 3.18 mg L-1. 相似文献
68.
Fangbing Liu Elena Sukhacheva Tatjana Erokhina Jörg Schubert 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(4):389-395
Potyviral nuclear inclusion b protein (NIb), the RNA-dependent RNA polymerase, contains three highly conserved regions. Peptides corresponding to these regions were synthesised and used for immunisation. A panel of monoclonal antibodies was obtained. Most of the MAbs reacted with the peptides and a recombinant NIb of PVY in PTA-ELISA. Two of them specifically detected native NIb of potato A, potato V, potato Y, plum pox and turnip mosaic potyviruses in extracts of infected plants in Western blots. Time course experiments revealed that NIb protein can be first detected on the fifth day after infection. 相似文献
69.
To investigate possible co-occurrences of type B trichothecenes and zearalenone within a Fusarium culmorum-infected wheat harvest lot, kernels were fractionated into six groups by visual criteria. The Fusarium-damaged kernels were subdivided into white, shrunken, and red kernel groups, and the remaining kernels were sorted into healthy, black spotted, and nonspecific groups. The distribution patterns of nivalenol, deoxynivalenol, zearalenone, and ergosterol were determined for possible correlations. Significant correlations between the distribution patterns were found for the mycotoxins and ergosterol for the grouped kernels (r = 0.997-0.999, p < 0.0001). Additionally, remarkably outstanding levels of nivalenol (24-fold more than the mean at 1.16 mg/kg), deoxynivalenol (27-fold more than the mean at 0.16 mg/kg), zearalenone (25-fold more than the mean at 77 microg/kg), and ergosterol (17-fold more than the mean at 13.4 mg/kg) were found in the red kernel group. Further, detailed mycotoxin and ergosterol analyses were carried out on various segments (kernel surface, conidia, bran, and flour) of the red kernels. However, the mycotoxin and ergosterol distribution profiles revealed nonsignificant correlations for these kernel segments, with the exception of deoxynivalenol and nivalenol, which were moderately correlated (r = 0.948, p = 0.035). 相似文献
70.
Obhodas Jasmina Tinivella Umberta Giustiniani Michela Durn Tatjana Vinkovic Andrija Radic Sara Soprun Filip Sudac Davorin 《Journal of Soils and Sediments》2020,20(6):2724-2732
Journal of Soils and Sediments - There is a growing understanding that methane hydrates (MHs) distributed globally in permafrost and deep sea sediments present an enormous unconventional reservoir... 相似文献