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For nutritional purposes, a survey of the vitamin B6 levels from a variety of commercial presentations of table olives was carried out, taking into account the three main processing types (Spanish-style, directly brined, and ripe olives). The analysis was performed by HPLC, following the official French method for vitamin B6 determination in foodstuffs. In-house validation data for two commercial table olives showed that the method precision was good (coefficient of variation <6%) and recovery was quantitative (104% on average). There was a wide range of values for vitamin B6 in table olives (0–69.3 μg/100 g edible portion). The highest mean content was found in directly brined olives (33.9 μg/100 g edible portion) followed by Spanish-style (14.4 μg/100 g) and ripe olives (4.3 μg/100 g). On average, samples of the Gordal and Carrasqueña cultivars showed the highest vitamin B6 content in the case of Spanish-style olives, but in directly brined olives as well as in ripe olives the effect of cultivar was not statistically significant (p?相似文献   
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Escherichia fergusonii has been associated with a wide variety of intestinal and extra-intestinal infections in both humans and animals but, despite strong circumstantial evidence, the degree to which the organism is responsible for the pathologies identified remains uncertain. Thirty isolates of E. fergusonii collected between 2003 and 2004 were screened using an Escherichia coli virulence gene array to test for the presence of homologous virulence genes in E. fergusonii. The iss (increased serum survival) gene was present in 13/30 (43%) of the test strains and the prfB (P-related fimbriae regulatory) and ireA (siderophore receptor IreA) genes were also detected jointly in 3/30 (10%) strains. No known virulence genes were detected in 14/30 (47%) of strains. Following confirmatory PCR and sequence analysis, the E. fergusoniiprfB, iss and ireA genes shared a high degree of sequence similarity to their counterparts in E. coli, and a particular resemblance was noted with the E. coli strain APEC O1 pathogenicity island. In tissue culture adherence assays, nine E. fergusonii isolates associated with HEp-2 cells with a ‘localised adherence’ or ‘diffuse adherence’ phenotype, and they proved to be moderately invasive. The E. fergusonii isolates in this study possess both some phenotypic and genotypic features linked to known pathotypes of E. coli, and support existing evidence that strains of E. fergusonii may act as an opportunistic pathogens, although their specific virulence factors may need to be explored.  相似文献   
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REASON FOR PERFORMING STUDY: The cytosolic protein complex, calprotectin, is abundant in neutrophils and could be used to improve the ability to localise and assess neutrophil infiltration in the equine intestine during ischaemia and reperfusion (I/R), but further study is required. OBJECTIVES: To assess the number of calprotectin-containing cells by immunohistochemistry in correlation with direct counting and scoring of neutrophils in the equine colon during I/R. METHODS: One and 2 h ischaemia of the left dorsal colon were induced, followed by 30 min reperfusion under general anaesthesia or by 18 h reperfusion after anaesthetic recovery. Biopsies were processed for light microscopy and stained with H/E for detection of neutrophils. To identify calprotectin-containing cells, immunohistochemistry was performed on formalin-fixed tissues with the murine MAC 387 antibody and a biotin-free peroxidase staining procedure. The number of neutrophils within submucosal venules and the colonic mucosa were calculated and compared with the number of calprotectin-positive cells. RESULTS: The number of calprotectin-positive cells within submucosal venules and within the colonic mucosa correlated significantly with the accumulation of neutrophils within the corresponding tissue segments. Within the submucosal venules, both calprotectin-positive cells and H/E-stained neutrophils increased with duration of ischaemia and peaked after 30 min of reperfusion. After 18 h reperfusion the number of these cells declined within the vessels. After 2 h ischaemia, neutrophils started to migrate into the mucosa towards the epithelium, with a significant increase over time during reperfusion, and peak infiltration after 18 h reperfusion. CONCLUSIONS: Neutrophil infiltration into the colon after I/R is a time-dependent process, involving migration through the submucosa towards the epithelium.  相似文献   
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