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261.
(-)-Epicatechin conjugates with sulfur-containing moieties are strong free radical scavengers with cell-protecting activities, which may be in part modulated by their capacity to bind to biological membranes. We present here a study of the interaction of these conjugates with membrane models such as multilamellar vesicles and a phospholipid-coated silica column (immobilized artificial membrane), monitored by differential scanning calorimetry and high-performance liquid chromatography, respectively. The nonpolyphenolic moiety significantly influenced the membrane behavior of the whole molecules. Bulky and hydrophobic conjugates clearly interacted with the phospholipids and may have a tendency to penetrate into the hydrophobic core of the vesicles. In contrast, the smaller cationic 4beta-(2-aminoethylthio)epicatechin may be located at the outer interface of the lipid membrane. The outcomes from both experimental set-ups were in good agreement. The differences detected in the biological activities of the conjugates may be explained in part by their tendency to penetrate the cell membrane.  相似文献   
262.
263.
Seventeen field surveys were done in four commercial orchards during six consecutive fruit-growing seasons from 2006 until 2011 in order to determine the current frequencies of occurrence of M. laxa, M. fructigena, and M. fructicola and their relative contributions to postharvest brown rot in peaches and nectarines in the Ebro Valley. The relative frequencies of occurrence of Monilinia spp. were determined on three sources of primary inoculum and on three sources of secondary inoculum. The major relative frequencies of Monilinia spp. were significantly recorded (P?=?0.05) from mummified fruit on the trees (approx. 42 %) and 7-day-old harvested fruit with brown rot (32 %), followed by that recovered from mummified fruit on the orchard bed (14 %), pruned branches on the orchard bed (8 %) and latent infections of immature fruit (3 %). We found that: (a) the relative frequency of M. fructicola has increased over the years to coexist on the same level as at the time M. laxa, (b) M. fructigena is no longer a cause of brown rot in harvested peaches, (c), a progressive reduction in the time of the first appearance of Monilinia airborne conidia (r?=??0.30, P?=?0.003), and the time of the first latent infection (r?=??0.44, P?=?0.0001) was detected along years after correlation analysis, and (d) these displacements are not associated with an increased incidence of brown rot disease. The M. fructicola increase was due to its significantly increased presence in 7-day-old harvested fruit with brown rot (r?=?0.73, P?=?0.0009), in latent infections of immature fruit (r?=?0.68, P?=?0.002), on pruned branches on the orchard bed (r?=?0.56, P?=?0.018), and on mummified fruit sampled on the trees (r?=?0.53, P?=?0.03). This progressive increase was accompanied by a progressive reduction in the relative frequency of occurrence of M. laxa in 7-day-old harvested fruit with brown rot (r?=??0.55, P?=?0.021) and M. fructigena on mummified fruit sampled on the trees (r?=??0.51, P?=?0.03).  相似文献   
264.
We determined the potential of using a formulated product based on Pantoea agglomerans CPA-2, either alone or in combination with heated sodium bicarbonate (SBC) solutions, to control the major postharvest diseases affecting citrus crops in the Mediterranean region. Treatments applied either individually or in combination were tested in semi-commercial and commercial trials carried out with oranges and mandarins from the Algarve, Andalusia and Catalonia. Firstly, several formulations of the biocontrol agents were tested in laboratory trials; one of them, a freeze-dried formulation of P. agglomerans strain CPA-2 called FD10-3, was chosen for combined with SBC. This formulation, applied at 2 × 108cfu ml−1 and the SBC treatment, applied at 3% 50°C for 20–40 s, demonstrated that it was possible to reduce decay development in laboratory trials. Semi-commercial applications of FD10-3 and 3% SBC solution at 50°C for 40 s showed excellent control of decay in unwounded mandarins and oranges artificially inoculated with both Penicillium digitatum and P. italicum. No rind injuries or residues attributable to hot water or SBC were observed on treated fruits. Combined treatment provided better control than the two treatments applied separately. Commercial trials demonstrated an important reduction in natural decay with the treatment of SBC 3% at 50°C for 40 s. Furthermore, bacterial-product formulation treatment significantly reduced the percentage of infected fruit and in some cases this reduction was equal to chemical treatments. Even so, no improvement in efficacy was observed with the combination of FD10-3 and SBC in the commercial test. We also assessed the ability of FD10-3 to grow at the wound site in oranges, whether alone or in the presence of SBC, and also its compatibility with standard citrus packinghouse practices.  相似文献   
265.
Bacillus subtilis CPA-8, a strain with demonstrated ability to control Monilinia spp. in peaches, was studied to elucidate its mechanisms of antifungal activity. Growth inhibition assays using cell-free supernatants and butanolic extracts showed strong antifungal activities against Monilinia laxa and Monilinia fructicola. By comparison with the reference B. subtilis strains UMAF6614 and UMAF6639, fengycin, iturin and surfactin lipopeptides were identified by thin layer chromatography in butanolic extracts from cell-free supernatants, indicating that antibiosis could be a major factor involved in the biological control ability of CPA-8. TLC-bioautography analysis confirmed the presence of fengycin, iturin and surfactin lipopeptides but strong antifungal activity could be associated only with fengycin lipopeptides. These results were definitively supported by mutagenesis analysis targeted to suppress fengycin biosynthesis by disruption of the B. subtilis fenB gene. By TLC-bioautography analysis it was possible to identify transformants from CPA-8 with reduced or suppressed antifungal activity, and this phenotype was associated with the lack of fengycin bands. Fruit trials confirmed that fengycin-defective mutants and their cell-free supernatants lost their ability to control peach brown rot disease in comparison with CPA-8 wild type strain or Serenade Max®, a commercial formulation based on B. subtilis. Furthermore, population dynamics studies determined that CPA-8 fengycin-deficient mutants survived in wounds in peach fruit equally well as the CPA-8 wild type. Taken together our data indicate that fengycin-like lipopeptides play a major role in the biological control potential of B. subtilis CPA-8 against peach brown rot.  相似文献   
266.
Biochemical reference intervals were determined for 31 clinically healthy Iberian lynxes (Lynx pardinus) between 1 and 6 years of age. Thirteen of the lynxes were wild-caught and the other 18 were captive-reared animals. The samples were collected between November 2004 and December 2006. The influence of sex (males vs. females), age (juveniles vs. adults) and habitat condition (free-living vs. captive) on the biochemical analytes were evaluated. Serum albumin concentrations were significantly higher in females than in males, while creatine phosphokinase was higher in males. The levels of alkaline phosphatase and lactate dehydrogenase were higher in juvenile lynxes, while gamma glutamyl-transferase and creatinine values were higher in adults. Lynxes captured in the wild had higher concentrations of iron, calcium, alkaline phosphatase and creatinine, but lower aspartate aminotransferase and alanine aminotransferase than lynxes maintained in captivity. The results were generally comparable to commonly reported reference intervals for other lynx species, the domestic cat and other felid species.  相似文献   
267.
Background: In veterinary medicine, there is increasing interest in measuring acute phase proteins as a tool in the diagnosis and monitoring of neoplastic diseases. Although mammary neoplasms are the most common type of cancer in dogs, acute phase proteins have not been extensively evaluated in dogs with mammary tumors. Objectives: The aim of this study was to evaluate serum haptoglobin (Hp) and C‐reactive protein (CRP) concentrations in the dogs with mammary tumors and assess their potential association with malignancy. Methods: A retrospective study of dogs with mammary tumors was performed. Serum concentrations of CRP and Hp were determined in healthy control dogs (n=20) and dogs with mammary tumors before surgery (n=41). Mammary tumors were grouped as carcinomas (n=24), fibrosarcoma (n=1), malignant mixed tumors (n=7), benign mixed tumors (n=6), and adenomas (n=3). CRP and Hp concentrations were compared in dogs with different tumor types and were also compared based on tumor size, lymph node infiltration, skin ulceration, fixation to underlying tissue, and time between tumor identification and removal. Results: Hp concentration was significantly (P<.043) higher in dogs with mammary tumors (median 2.03 g/L, range 0.09–2.94 g/L) compared with controls (1.38 g/L, range 0.08–3.00 g/L), but the range of values overlapped considerably. CRP concentration was higher in dogs with carcinomas (4.70 mg/L, range 0.63–128.96 mg/L) vs controls (2.11 mg/L, range 0.25–6.57 mg/L) (P=.0008) and in dogs with ulcerated skin (14.8 mg/L, range 5.7–128.9 mg/L, n=3) compared with those without ulceration (2.4 mg/L, range 0.11–30.3 mg/L, n=38) (P=.048). Conclusions: Serum Hp and CRP do not appear to have value in diagnosing or predicting malignancy of mammary tumors in dogs. Higher CRP concentrations in dogs with mammary carcinoma suggest a role for inflammation in this tumor type.  相似文献   
268.
The frequencies of feline blood types in northern Portugal were studied by surveying 185 pedigreed and nonpedigreed cats. Blood typing was performed by the traditional tube method. As a single group, the majority of cats were type A (90.3%), 3.8% were type B, and 5.9% were type AB. Among pedigreed cats, 19 were Siamese and 7 were Persian; all but 1 were type A. Among nonpedigreed cats, 89.3% were type A, 4.4% were type B, and 6.3% were type AB.  相似文献   
269.
A semiautomatic electronic blood cell counter (Sysmex F-800:Toa Medical Electronics Europa Gmbh, Hamburg, Germany) was evaluated using canine and feline blood, following the International Committee for Standardization in Hematology protocol (ICSH, 1984). Precision and overall reproducibility were acceptable for all the parameters studied except for the feline platelet count, in which overlapping of erythrocyte and platelet populations prohibited determination of an accurate platelet count. Since carry-over from canine hematocrit values and platelet counts and from feline hematocrit values was unsatisfactory, the use of a blank diluent sample between different analyses was necessary. Linearity of the analyzer was acceptable in the studied range. Thirty canine and feline blood samples were analyzed using the Sysmex F-800 and a manual method. Correlations between both methods were acceptable for all the parameters, except for feline platelet count and erythrocyte indices for both species. In the storage study, red blood cell count and hemoglobin concentration were the parameters with the longest stability (72 hours at 4 degrees C and 25 degrees C) in both species. A statistically significant increase in MCV was obtained at 12 hours post-extraction in canine samples stored at 25 degrees C and at 24 hours in refrigerated samples. Feline leucocyte counts showed a downward trend at 12 hours post-extraction at both temperatures. Canine platelet count decreased significantly at 6 hours post-extraction in samples stored at 4 degrees C. During the evaluation period, Sysmex F-800 was user friendly and appeared well suited for routine canine and feline blood cell analysis.  相似文献   
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