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951.
Lydie W.J.H. van den Crommenacker-Konings Petra van Dam Reinard Everts Aminu Shittu Mirjam Nielen Theo J.G.M. Lam Gerrit Koop 《Journal of dairy science》2021,104(5):5979-5987
Mastitis is an important problem in meat-producing sheep, but few studies have investigated the transmission dynamics of mastitis pathogens in these animals. The objective of this study was to describe the pathogens causing intramammary infections (IMI) in suckler ewes, their effect on somatic cell count, and the dynamics of these IMI in early lactation. We enrolled 15 sheep flocks early after lambing and selected ewes in each flock that were sampled twice with a 3-wk interval. Milk samples from both glands of each ewe were bacteriologically cultured, and somatic cell count was measured. Non-aureus Staphylococcus spp. were the most prevalent culture results. Somatic cell counts were most strongly increased in ewes infected with Mannheimia haemolytica, whereas staphylococci, including Staphylococcus aureus, were associated with a moderate increase in somatic cell count. The proportion of udder halves that remained culture-positive with Staphylococcus spp. during the 3-wk sampling interval was moderate, but M. haemolytica infections were stable during this time period. A substantial number of new infections were seen in the early lactation study period for non-aureus Staphylococcus spp., Staph. aureus, and Corynebacterium spp., but not for M. haemolytica or Streptococcus spp. The number of new IMI of Staph. aureus was associated with the number of Staph. aureus-infected udder halves in the flock at the first sampling moment, indicative of contagious transmission. Altogether, we show that substantial transmission happens in early lactation in suckler ewes, but that the dynamics differ between pathogen species. More research is needed to further describe transmission in different stages of lactation and to identify transmission routes, to develop effective interventions to control mastitis. 相似文献
952.
Zsofia Kutil Marie Kvasnicova Veronika Temml Daniela Schuster Petra Marsik Eloy Fernandez Cusimamani 《International Journal of Food Properties》2013,16(7):1471-1477
Stilbenes contained in various foods are associated with health beneficial effects. In this study six natural and one synthetic stilbene were tested for their potential to regulate the activity of lipoxygenase and cyclooxygenase in vitro. The most potent inhibitor of 5-lipoxygenase was pterostilbene (IC50 = 9.32 μM), whereas the strongest inhibitor of cyclooxygenase-1 and cyclooxygenase-2 was pinostilbene (IC50s = 1.90 and 0.35 μM, respectively). Pterostilbene (IC50s = 11.70 and 27.04 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) and oxyresveratrol (IC50s = 18.49; 2.79 and 14.71 μM for 5-lipoxygenase, cyclooxygenase-1, and cyclooxygenase-2, respectively) were capable to inhibit catalytic activity of all three tested enzymes. Isorhapontigenin (IC50s = 8.81 and 24.00 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) and rhapontigenin (IC50s = 24.55 and 36.12 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) were only moderate or weak inhibitors of both cyclooxygenase forms. In summary, these results indicated that besides the known cyclooxygenase inhibitor resveratrol also other natural stilbenes could be potent inhibitors of the arachidonic acid pathway and deserve further attention as compounds with promising health benefits. 相似文献
953.
Bernadetta Hozová Ladislav Dodok Jana Olekšáková Petra Moravčíková 《International Journal of Food Properties》2013,16(4):897-906
Effect of selected additives and their combinations on the sensory quality of final cereal products prepared from the mixture of flours (wheat T 650, rye T 930, and spelt) and from wheat flour T 512 was studied. The following sensory parameters were considered: shape (cambering); crust (color, thickness, hardness); crust/crumb (odor, taste); crumb (elasticity, porosity, color, hardness (resistance to bite); adhesiveness (to palate at longer chewing). It was found that sensory parameters increased after the application of the selected combinations of improving additive substances (ascorbic acid, enzymes and emulsifiers) and concentration of the enzyme preparation Lipopan 50 BG had a positive effect on sensory parameters and on the reduction of the applied amount of emulsifiers in the final product. 相似文献
954.
955.
Raphael J. Nawrotzki Kristin Robson Margaret J. Gutilla Lori M. Hunter Wayne Twine Petra Norlund 《Food Security》2014,6(2):283-297
Recurring food crises endanger the livelihoods of millions of households in developing countries around the globe. Owing to the importance of this issue, we explored recent changes in food security between the years 2004 and 2010 in a rural district in Northeastern South Africa. Our study window spans the time of the 2008 global food crisis and allows the investigation of its impacts on rural South African populations. Grounded in the sustainable livelihood framework, we examined differences in food security trajectories among vulnerable sub populations. A unique panel data set of 8,147 households, provided by the Agincourt Health and Demographic Surveillance System (Agincourt HDSS), allowed us to employ a longitudinal multilevel modeling approach to estimate adjusted growth curves for the differential changes in food security across time. We observed an overall improvement in food security that leveled off after 2008, most likely resulting from the global food crisis. In addition, we discovered significant differences in food security trajectories for various sub populations. For example, female-headed households and those living in areas with better access to natural resources differentially improved their food security situation, compared to male-headed households and those households with lower levels of natural resource access. However, former Mozambican refugees witnessed a decline in food security. Therefore, poverty alleviation programs for the Agincourt region should work to improve the food security of vulnerable households, such as former Mozambican refugees. 相似文献
956.
Martin D’Agostino Nigel Cook Ilaria Di Bartolo Franco M. Ruggeri Alessandra Berto Francesca Martelli Malcolm Banks Petra Vasickova Petr Kralik Ivo Pavlik Petros Kokkinos Apostolos Vantarakis Kirsi S?derberg Leena Maunula Katharina Verhaelen Saskia Rutjes Ana Maria de Roda Husman Renate Hakze Wim Van der Poel Agnieszka Kaupke Iwona Kozyra Artur Rze?utka Jasna Prodanov Sava Lazic Tamas Petrovic Anna Carratala Rosina Gironés Marta Diez-Valcarce Marta Hernandez David Rodriguez-Lazaro 《Food Analytical Methods》2012,5(1):1-7
The qualitative performance characteristics of a qPCR-based method to detect human adenoviruses in raspberries were determined through a collaborative trial involving 11 European laboratories. The method incorporated a sample process control (murine norovirus) and an internal amplification control. Trial sensitivity or correct identification of 25-g raspberry samples artificially contaminated with between 5?×?102 and 5?×?104?PFU was 98.5%; the accordance and concordance were 97.0%. The positive predictive value was 94.2%. The trial specificity or percentage correct identification of non-artificially contaminated samples was 69.7%; the accordance was 80.0% and the concordance was 61.7%. The negative predictive value was 100%. Application of a method for the detection of human adenoviruses in food samples could be useful for routine monitoring for food safety management. It would help to determine if a route of contamination exists from human source to food supply chain which pathogenic viruses such as norovirus and hepatitis A virus could follow. 相似文献
957.
O. V. Zillich U. Schweiggert‐Weisz P. Eisner M. Kerscher 《International journal of cosmetic science》2015,37(5):455-464
Polyphenols are secondary plant metabolites with antioxidant, anti‐inflammatory and anti‐microbial activity. They are ubiquitously distributed in the plant kingdom; high amounts contain, for example, green tea and grape seeds. Polyphenolic extracts are attractive ingredients for cosmetics and pharmacy due to their beneficial biological properties. This review summarizes the effects of polyphenols in the context of anti‐ageing activity. We have explored in vitro studies, which investigate antioxidant activity, inhibition of dermal proteases and photoprotective activity, mostly studied using dermal fibroblasts or epidermal keratinocytes cell lines. Possible negative effects of polyphenols were also discussed. Further, some physicochemical aspects, namely the possible interactions with emulsifiers and the influence of the cosmetic formulation on the skin delivery, were reported. Finally, few clinical studies, which cover the anti‐ageing action of polyphenols on the skin after topical application, were reviewed. 相似文献
958.
Impact of treatment processes on the removal of perfluoroalkyl acids from the drinking water production chain 总被引:2,自引:0,他引:2
Eschauzier C Beerendonk E Scholte-Veenendaal P De Voogt P 《Environmental science & technology》2012,46(3):1708-1715
The behavior of polyfluoralkyl acids (PFAAs) from intake (raw source water) to finished drinking water was assessed by taking samples from influent and effluent of the several treatment steps used in a drinking water production chain. These consisted of intake, coagulation, rapid sand filtration, dune passage, aeration, rapid sand filtration, ozonation, pellet softening, granular activated carbon (GAC) filtration, slow sand filtration, and finished drinking water. In the intake water taken from the Lek canal (a tributary of the river Rhine), the most abundant PFAA were PFBA (perfluorobutanoic acid), PFBS (perfluorobutane sulfonate), PFOS (perfluorooctane sulfonate), and PFOA (perfluorooctanoic acid). During treatment, longer chain PFAA such as PFNA (perfluorononanoic acid) and PFOS were readily removed by the GAC treatment step and their GAC effluent concentrations were reduced to levels below the limits of quantitation (LOQ) (0.23 and 0.24 ng/L for PFOS and PFNA, respectively). However, more hydrophilic shorter chain PFAA (especially PFBA and PFBS) were not removed by GAC and their concentrations remained constant through treatment. A decreasing removal capacity of the GAC was observed with increasing carbon loading and with decreasing carbon chain length of the PFAAs. This study shows that none of the treatment steps, including softening processes, are effective for PFAA removal, except for GAC filtration. GAC can effectively remove certain PFAA from the drinking water cycle.The enrichment of branched PFOS and PFOA isomers relative to non branched isomers during GAC filtration was observed during treatment. The finished water contained 26 and 19 ng/L of PFBA and PFBS. Other PFAAs were present in concentrations below 4.2 ng/L The concentrations of PFAA observed in finished waters are no reason for concern for human health as margins to existing guidelines are sufficiently large. 相似文献
959.
960.
In the presented article, an in situ weighing system for the measurement of drying rate and residual water content during vacuum drying was tested and validated with offline analyses. The influence of buoyancy effects was studied both experimentally and theoretically in terms of sample volume and final pressure. Furthermore, the effect of time drifts on the measured drying rate and residual water content were studied and the measurement errors were quantified for the drying of sorbitol solutions. It was shown that the drying rate and thus residual water content could be determined with good accuracy with the present measurement system. 相似文献