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31.
The protein and mineral composition of different varieties of three different lupin species (Lupinus albus, Lupinus angustifolius, and Lupinus luteus) and the effect of alpha-galactoside removal by means of a hydroalcoholic extraction process on such composition were studied in relationship to nutrient distribution among the different anatomical parts of the seed (embryo, cotyledon, and seed coat). The extent of processing-derived protein insolubilization was assessed by both chemical and electrophoretic techniques and related to the amount of nitrogen soluble in H(2)O, NaCl, ethanol, NaOH, and sodium dodecyl sulfate/beta-mercaptoethanol (SDS/BME). The alpha-galactoside extraction process caused a significant increase in the amount of total and insoluble nitrogen and decreased the amount of soluble protein nitrogen, without affecting the content of soluble nonprotein nitrogen. alpha-Galactoside extraction was not effective at decreasing the levels of Mn present in lupins, and processing caused an increase in the content of this mineral in all of the species studied with the exception of L. albus var. multolupa. In general, the effect of processing on mineral content varied with the different lupin species, and mineral losses were lower in L. luteus.  相似文献   
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This paper describes an outbreak of Trypanosoma vivax for the first time in the state of Pernambuco, Brazil, affecting dairy cattle in the municipality of Itambé in the northern coastal zone of the state. Clinical signs compatible with infection by blood protozoa and epidemic miscarriages were observed. The diagnosis of T. vivax was confirmed through biometric microscopy and molecular analysis with PCR and DNA sequencing. The T. vivax isolate detected in the present study proved to be genetically very close to other Brazilian isolates of the protozoan despite being geographically distant.  相似文献   
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From the roots of Iostephane heterophylla, six known compounds, namely, ent-trachyloban-19-oic acid (1), the mixture of ent-kaur-16-en-19-oic acid (2) and ent-beyer-15-en-19-oic acid (3), xanthorrhizol (4), 16α-hydroxy-ent-kaurane (5) and 16α-hydroxy-ent-kaur-11-en-19-oic acid (6) were isolated using a bioassay-guided fractionation method. The known compounds (1-6) were identified by comparison of their spectroscopic data with reported values in the literature. In an attempt to increase the resultant antimicrobial activity of 1 and 4, a series of reactions was performed on ent-trachyloban-19-oic acid (1) and xanthorrhizol (4), to obtain derivatives 1a, 1b, and 4a-4d. All the isolated compounds (1-6) and the derivatives 1a, 1b, and 4a-4d were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Porphyromonas gingivalis associated with caries and periodontal disease, respectively. Compounds 1, 1b, 2+3, 4 and 4d inhibited the growth of S. mutans with concentrations ranging from 4.1 μg/mL to 70.5 μg/mL. No significant activity was found on P. gingivalis except for 4 with an MIC of 6.8 μg/mL. The ability of 1, 1b, 2+3, 4 and 4d to inhibit biofilm formation by S. mutans was evaluated. It was found that 1, 1b, 4 and 4d interfered with the establishment of S. mutans biofilms, inhibiting their development at 32.5, 125.0, 14.1 and 24.4 μg/mL, respectively.  相似文献   
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The primary structure of the double-headed Bowman-Birk inhibitor (BBI) family and the antitryptic activity were investigated in cultivated and wild Phaseolus species. Two BBI types were identified; the first one inhibits trypsin and chymotrypsin (tc-BBI), the second one elastase and trypsin (et-BBI). Only tc-BBI was found in P. lunatus and P. parvulus, while none of BBI types, identified in this study, was found in P. leptostachyus. The deduced amino acid sequences revealed some polymorphisms within both tc-BBI and et-BBI binding loops that could affect the inhibitory activity. The trypsin inhibitor content showed a high variation with the lowest value recorded in P. lepthostachyus and the highest one observed in P. oligospermus. Southern blot analysis confirmed the absence of both BBI types in P. leptostachyus and suggests that in P. coccineus, P. dumosus and P. costaricensis, the two genes were clustered in a narrow genomic region of 1.3 kbp.  相似文献   
37.

Purpose

In soils from serpentinitic areas the natural background of Ni and Cr is so high that the assessment of contamination by comparing metal concentrations with some fixed thresholds may give unreliable results. We therefore sought a quantitative relation between serpentines and Ni and Cr concentrations in uncontaminated soils, evaluated if the approach may help in establishing a baseline, and discussed if additional anthropogenic inputs of Ni and Cr can be realistically individuated in these areas.

Materials and methods

We analysed the total, acid-extractable and exchangeable concentrations of Ni and the total and acid-extractable concentrations of Cr in 66 soil horizons, belonging to 19 poorly developed and uncontaminated Alpine soils. The soils had different amounts of serpentines, depending on the abundance of these minerals in the parent material. We calculated an index of abundance of serpentines in the clay fraction by XRD and related total metal contents to the mineralogical index. We then tested the regressions on potentially contaminated soils, developed on the alluvial plain of the same watershed.

Results and discussion

We found extremely high total concentrations of Ni (up to 1,887 mg kg–1) and Cr (up to 2,218 mg kg–1) in the uncontaminated soils, but only a small proportion was extractable. Total Ni and Cr contents were significantly related to serpentine abundance (r 2?=?0.86 and 0.74, respectively). The regressions indicated that even small amounts of serpentines induced metal contents above 200 mg kg–1, and the 95% confidence limits were 75 and 111 mg kg–1 of Ni and Cr, respectively. When the regressions were tested on the potentially contaminated soils, a good estimate was obtained for Cr, while the Ni concentration was overestimated, probably because of some leaching of this element.

Conclusions

The concentrations of Ni and Cr that can be expected in soils because of the presence of small amounts of serpentines are comparable to the amounts accumulated in the soil because of diffuse contamination and potentially contaminated soils had metal concentrations falling in the range expected from the presence of natural sources. Only in the case of very severe contamination events, the identification of anthropogenic sources adding to the natural background would be feasible.  相似文献   
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Objective To evaluate the mydriatic efficacy of a neuromuscular blocking agent (rocuronium bromide) applied topically to only one eye of nocturnal birds of prey and to assess for any general and/or local adverse effects due to its use. Animal studied Twelve healthy adult tawny owls (Strix aluco) were randomly divided in two groups. Procedures Six birds (Group 1) received a single dose of 0.35 mg of rocuronium bromide. The second group of subjects (Group 2) received two doses of 0.35 mg of rocuronium bromide (total 0.70 mg/eye). In both groups, the curariform agent was instilled topically. Pupil diameter was measured with a pupillary gauge in 10 min intervals for a total of 100 min and then every 20 min for a total of 240 min. The assessment of the pupillary light reflex was performed using a standard light source during pupillary size recording. Results Maximal pupillary diameter was 11.5 ± 0.3 mm for Group 1 and 11.0 ± 0.6 mm for Group 2 and no statistically significant differences were detected among the two groups. The maximal pupillary diameter was achieved at T80 for Group 1, and at T60 for Group 2. A complete fundus examination was possible on all treated eyes of subjects of both groups. The drug did not cause any noticeable adverse effects in any of the examined birds. Conclusion Results of the present study suggest that a single topical administration of 0.35 mg of rocuronium bromide to the eyes of healthy tawny owls results in sufficient mydriasis to allow for a complete examination of the fundus.  相似文献   
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