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61.
In this study, oil bodies (OBs) from Gevuina avellana (OBs-G) and Madia sativa (OBs-M) were isolated and characterized. Microscopic inspection revealed that the monolayer on OB-G was thinner compared to that on OB-M. Cytometric profiles regarding size, complexity, and staining for the two OB sources were similar. Fatty acid to protein mass ratio in both OBs was near 29, indicating high lipid enrichment. OBs-G and OBs-M showed a strong electrostatic repulsion over wide ranges of pH (5.5-9.5) and NaCl concentration (0-150 mM). Proteins displaying highly conserved sequences (steroleosins and aquaporins) in the plant kingdom were identified. The presence of oleosins was immunologically revealed using antibodies raised against Arabidopsis thaliana oleosins. OBs-G and OBs-M exhibited no significant cytotoxicity against the cells. This is the first report about the isolation and characterization of OBs-G and OBs-M, and this knowledge could be used for novel applications of these raw materials.  相似文献   
62.
Forty four marine actinomycetes of the family Microccocaceae isolated from sponges collected primarily in Florida Keys (USA) were selected from our strain collection to be studied as new sources for the production of bioactive natural products. A 16S rRNA gene based phylogenetic analysis showed that the strains are members of the genera Kocuria and Micrococcus. To assess their biosynthetic potential, the strains were PCR screened for the presence of secondary metabolite genes encoding nonribosomal synthetase (NRPS) and polyketide synthases (PKS). A small extract collection of 528 crude extracts generated from nutritional microfermentation arrays was tested for the production of bioactive secondary metabolites against clinically relevant strains (Bacillus subtilis, methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter baumannii and Candida albicans). Three independent isolates were shown to produce a new anti-MRSA bioactive compound that was identified as kocurin, a new member of the thiazolyl peptide family of antibiotics emphasizing the role of this family as a prolific resource for novel drugs.  相似文献   
63.
64.
The objective of this study was to evaluate and compare, for the first time, white and black mulberry species in terms of main phytochemical, volatile composition and sensory profile characteristics in eight Spanish clones. The results showed that black and white mulberry species displayed significant different characteristics. PLS analysis has allowed grouping of the clones into four groups (i) MA1, MA2 and MN2, (ii) MN3 and MN4, (iii) MA3 and MA4, and (iv) MN1. Experimental results proved that Spanish mulberries have potential for fresh consumption due to their high antioxidant capacity (10.7–86.1 mg Trolox 100 g?1), polyphenol (76.7–180 mg gallic acid 100 g?1) and ellagic acid content (8.7–15.5 mg 100 g?1) as well as considerable amount of volatile compounds (35) with desirable attributes, which were scored high by a trained panel. Cultivars from the Morus nigra species seem to provide fruits with higher content of bioactive compounds and better aptitude for fresh consumption than Morus alba. Differences among the species should be attributed to genetics because they were cultivated under same conditions.  相似文献   
65.
66.
The objective of this work was to evaluate the antioxidant and antihemolytic activities of crude, aqueous, and organic-aqueous extracts of maqui ( Aristotelia chilensis ) and murta ( Ugni molinae Turcz.), together with their inhibiting effect on enzymes involved in the metabolism of carbohydrates. Radical scavenging activity, inhibition of linoleic acid oxidation in a micellar system, antihemolytic activity, and inhibition of α-amylases and α-glucosidases were analyzed. Crude extracts of maqui leaves and fruits were found to be important sources of polyphenolic compounds, showing 69.0 ± 0.9 and 45.7 ± 1.1 mg GAE/g dm, respectively. Polyphenols from maqui leaves were active as antioxidants and antihemolytic compounds (p < 0.05), showing a noncompetitive inhibiting effect on α-glucosidase. Flavan-3-ol polymers and glycosylated flavonols, such as quercetin glucoside and kaempferol glucoside, were tentatively identified in extracts. This preliminary observation provides the basis for further examination of the suitability of polyphenol-enriched extracts from maqui and murta as nutritional or medicinal supplements with potential human health benefits.  相似文献   
67.

Background

Chronic inflammation is involved in the pathogenesis of human cervical spondylotic myelopathy and could also play a role in cervical spondylomyelopathy (CSM) in dogs.

Hypothesis/Objectives

That cerebrospinal fluid (CSF) cytokine concentrations would differ between clinically normal (control) and CSM‐affected Great Danes (GDs), with affected GDs showing higher levels of inflammatory cytokines, such as interleukin (IL)‐6 and monocyte chemoattractant protein‐1/chemokine ligand 2 (MCP‐1/CCL2).

Animals

Client‐owned GDs: 15 control, 15 CSM‐affected.

Methods

Prospective study. Dogs underwent cervical vertebral column magnetic resonance imaging and collection of CSF from the cerebellomedullary cistern. Cytokine concentrations were measured using a commercially available canine multiplex immunoassay. Cytokine concentrations were compared between groups. Associations with the administration of anti‐inflammatory medications, disease duration and severity, severity of spinal cord (SC) compression, and SC signal changes were investigated in affected GDs.

Results

Affected GDs had significantly lower MCP‐1/CCL2 (mean 138.03 pg/mL, 95% confidence interval [CI] = 114.85–161.20) than control GDs (212.89 pg/mL, 95% CI = 165.68–260.11, = .028). In affected GDs, MCP‐1/CCL2 concentrations correlated inversely with the severity of SC compression. There were no associations with administration of anti‐inflammatory medications, disease duration, or disease severity. IL‐6 concentrations were significantly higher (2.20 pg/mL, 95% CI = 1.92–2.47, < .001) in GDs with SC signal changes.

Conclusions and Clinical Importance

Lower MCP‐1/CCL2 in CSM‐affected GDs might compromise clearance of axonal and myelin debris, delay axon regeneration, and affect recovery. Higher IL‐6 in CSM‐affected GDs with SC signal changes suggests more severe inflammation in this group.  相似文献   
68.
Great Danes are predisposed to osseous‐associated cervical spondylomyelopathy (Wobbler syndrome). The first aim of this prospective study was to compare values measured using previously published intravertebral and intervertebral ratio methods and a novel ventrodorsal ratio method in radiographs of clinically normal and affected Great Danes. The second aim was to determine whether these ratios could be used as predictors of sites of spinal cord compression based on magnetic resonance imaging (MRI). Thirty dogs (15 normal, 15 affected) were prospectively enrolled. Lateral and ventrodorsal radiographs were obtained and six measurements were recorded from C3‐T1. For each vertebral location, intravertebral ratios and intervertebral ratios were calculated from lateral views, and the ratio of the distance between the articular process joints vs. vertebral body width (novel ventrodorsal ratio) was calculated from ventrodorsal views. Values for these three ratios were compared, by vertebral location and dog group. Intravertebral and intervertebral ratios did not differ between dog groups. The ventrodorsal ratio was significantly smaller in affected Great Danes at C5–6 (P = 0.005) and C6–7 (P < 0.001). The ventrodorsal ratio was significantly associated with MRI presence of spinal cord compression. For each 0.1 unit increase in this ratio value, there was a 65% decrease in the odds of spinal cord compression being present at that site, independent of vertebral location (P = 0.002). Findings from this study supported use of the novel ventrodorsal ratio as an initial radiographic screening method for Great Danes with suspected cervical spondylomyelopathy.  相似文献   
69.
Halo-blight is an important worldwide bacterial disease of common bean (Phaseolus vulgaris L.) caused by Pseudomonas syringae pv. phaseolicola. Nine races of the pathogen and five race-specific resistance genes have been previously described. However, a quantitative response to this pathogen has also been described. The objective of this study was to identify halo-blight resistance loci linked to molecular markers that could be used in resistance breeding. Chromosomal regions related to race 5 halo-blight resistance were localized on a genetic map of RAPD and AFLP molecular markers and constructed by the analysis of a “Jules” × “Canela” F2 progeny. “Jules” shows quantitative resistance to halo-blight and “Canela” is a very appreciated but susceptible Spanish bean landrace. Two QTL for resistance to halo-blight were mapped in two linkage groups. There were four large groups, with 14–22 molecular markers each, five with 4–8 markers each, and three with 2 or 3 markers each.  相似文献   
70.
Casein-glucose-fructose mixtures unheated (C) or after heating (HC) were added to a solution of ionic calcium to study calcium speciation and included in diets (C-D, HC-D) for rats. Samples and diets were digested in vitro. Supernatants of digested samples were used for transport experiments with Caco-2 cells. Total soluble and ionic calcium levels were lower and precipitated calcium levels higher with HC compared to C. Dialyzed calcium from the diets was highly ionic and lower in HC-D compared to C-D. Nondialyzed soluble calcium was also lower, whereas precipitated calcium was higher, in HC-D. HC increased calcium transport in Caco-2 cells compared to C, but transport efficiency decreased due to lower calcium solubililty after digestion. Urinary calcium increased with HC-D consumption without changes in calcium absorbed and retained. Maillard reaction products in HC decrease calcium solubility, but enterocyte metabolism and calcium absorption and retention seem to be unaffected. Nevertheless, urinary calcium losses increase.  相似文献   
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