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71.
This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein containing the extracellular region of chCD83 was expressed in Chinese Hamster Ovary (CHO) cells and isolated from the spent cell culture medium by protein G affinity chromatography. The extracellular region of the chCD83 protein was purified and used to immunize mice. A cell fusion was performed, from which 342 hybridomas were screened for mAbs to chCD83. Two mAbs, chCD83-159 and chCD83-227, stained the greatest percentage of chCD83-transfected CHO cells and were selected for further characterization. By flow cytometry, both mAbs reacted with a chicken macrophage cell line, HD11. Both mAbs also recognized a single 53 kDa protein on Western blots of lysates from lipopolysaccharide-stimulated spleen mononuclear cells or unstimulated HD11 cells. Immunostaining of chicken secondary lymphoid organs identified chCD83(+) cells with morphologic and subtissue localization properties comparable to mammalian DCs. In vitro stimulation of spleen mononuclear cells with concanavalin A (Con A) decreased the percentage of chCD83(+) cells compared with cells treated with medium alone. Interestingly, spleen cells treated with Con A in the presence of chCD83-227 mAb exhibited decreased percentage of MHCII(+) cells compared with cells treated with an isotype-matched negative control mAb. These chCD83 mAbs may be useful for future investigations of chicken immune cell maturation and mechanisms of action.  相似文献   
72.
Rabbits absorb more calcium (Ca) from their diet than they require, and excrete surplus via urine, which therefore contains a typical 'sludge'. This makes rabbits susceptible to Ca-containing uroliths. But given the Ca content of diets of free-ranging specimens, and the limited reports of urinary sludge and Ca contents in free-ranging lagomorphs, we can suspect that rabbits are naturally adapted to high urinary Ca loads. We fed four groups of New Zealand hybrid rabbits [n = 28, age at start 5-6 weeks) pelleted diets consisting of lucerne hay only (L, Ca 2.32% dry matter (DM)], lucerne:oats 1:1 (LG, Ca 1.36%), grass hay only (G, Ca 1.04%), or grass:oats 1:1 (GG, 0.83%) for 25 weeks, with water available ad libitum. Diets were not supplemented with Ca, phosphorus, or vitamin D. Rabbits on diets LG and GG had lower food and water intakes, lower faeces and urine output, grew faster and had higher body mass at slaughter (mainly attributable to adipose tissue). Apparent Ca digestibility decreased in the order L-LG-G/GG. Rabbits on L had larger and heavier kidneys, more urinary sediment at sonography, and a higher urinary Ca content than the other groups. No animal showed signs of urolithiasis/calcinosis at X-ray, sonography, or gross pathology. Kidney/aorta histology only sporadically indicated Ca deposits, with no systematic difference between groups. Under the conditions of the experiment, dietary Ca loads in legume hay do not appear problematic for rabbits, and other factors, such as water supply and level of activity may be important contributors to urolithiasis development in veterinary patients. However, due to the lower Ca content of grass hay, the significantly lower degree of urinary sludge formation, and the significantly higher water intake related with grass hay feeding, grass hay-dominated diets are to be recommended for rabbits in which urolithiasis prevention is an issue.  相似文献   
73.
A new commercially available ELISA (ELISAr-Chlamydia) for detecting antibodies against Chlamydophila abortus has been evaluated using sheep field serum samples. The ELISA is based on a recombinant antigen which expresses part of a protein from the 80-90kDa family that is specific to C. abortus. Sera (105) from six flocks with confirmed ovine chlamydial abortion (OEA) outbreaks were used in this study, as well as sera (258) from 18 flocks which had suffered no OEA in the last lambing. The ELISAr-Chlamydia was compared with the complement fixation test (CFT) and with an ELISA using purified C. abortus elementary bodies (ELISA-EB), employing as reference technique a comparative microimmunofluorescence test that differentiates C. abortus infection from Chlamydophila pecorum infection. The results showed that the sensitivity of ELISAr-Chlamydia was 90.9% with a specificity of 85.9%, the sensitivity of CFT was 71.0% with a specificity of 83.6%, while the sensitivity of ELISA-EB was 95.2% and the specificity was 54.2%. Furthermore, ELISAr-Chlamydia was the test with fewer false positives resulting from positive reactivity to C. pecorum, although 15% of the sera positive for C. pecorum but negative for C. abortus antibodies reacted positively. This study demonstrated with field material that ELISAr-Chlamydia provides the most balanced results between sensitivity and specificity, especially in flocks with no clinical OEA but reactivity to C. abortus.  相似文献   
74.
Coffee is globally one of the most important export crops and is a prominent part of the economy in more than 50 countries in Latin America, Africa and Asia. In Colombia, it has been the leading export commodity for more than a century. However, genetic research on coffee has been rather sparse and mainly focused on the two major cultivated species, Coffea arabica L. and C. canephora P., leaving unexplored the genetic potential in other species. In this study, an interspecific mapping population consisting of 101 F1 hybrid plants from a cross between the diploid species C. liberica and C. eugenioides was evaluated for genetic segregation at 618 molecular marker loci. Of these, 168 SSRs and two ESTs exhibited polymorphic patterns that allowed segregation analysis and genetic linkage estimations. A genetic map consisting of 146 co-dominant loci and 11 predicted linkage groups was constructed using the mapping software JoinMap 3.0. The conjoined maternal/paternal map length is 798.68 cM, has an average saturation density of 6.01 cM/interval, and covers an estimated 66–86 % of the diploid coffee genome. Approximately 24 % of loci had null alleles, and 23.5 % exhibited segregation distortion. Knowledge derived from this study has important applications for quantitative trait locus analysis and marker-assisted selection in Colombian coffee breeding programs.  相似文献   
75.
Hewson, J., Johnson, R., Arroyo, L. G., Diaz‐Mendez, A., Ruiz‐López, J. A., Gu, Y., del Castillo, J. R. E. Comparison of continuous infusion with intermittent bolus administration of cefotaxime on blood and cavity fluid drug concentrations in neonatal foals. J. vet. Pharmacol. Therap.  36 , 68–77. Healthy neonatal foals were treated with cefotaxime by bolus (40 mg/kg IV q6h for 12 doses; n = 10) or by infusion (loading dose of 40 mg/kg IV followed by continuous infusion of a total daily dose of 160 mg/kg per 24 h for 3 days; n = 5). Population pharmacokinetics was determined, and concentrations in cavity fluids were measured at steady state (72 h). Highest measured serum drug concentration in the bolus group was 88.09 μg/mL and minimum drug concentration (Cmin) was 0.78 μg/mL at 6‐h postadministration (immediately before each next dose), whereas infusion resulted in a steady‐state concentration of 16.10 μg/mL in the infusion group. Mean cefotaxime concentration in joint fluid at 72 h was higher (P = 0.051) in the infusion group (5.02 μg/mL) compared to the bolus group (0.78 μg/mL). Drug concentration in CSF at 72 h was not different between groups (P = 0.243) and was substantially lower than serum concentrations in either group. Insufficient data on pulmonary epithelial lining fluid were available to compare the methods of administration for cefotaxime in this cavity fluid. Results support continuous drug infusion over bolus dosing in the treatment for neonatal foal septicemia to optimize time that cefotaxime concentration exceeds the minimum inhibitory concentration of common equine pathogens.  相似文献   
76.
Precision Agriculture - The development of small unmanned aerial vehicles and advances in sensor technology have made consumer digital cameras suitable for the remote sensing of vegetation. In this...  相似文献   
77.
The objective of this work was to investigate the effect of fatty acid (FA) type and content on mechanical properties, water vapor permeability and oxygen permeability of hydroxypropyl methycellulose (HPMC)-beeswax (BW) stand-alone edible films. The effect of these films formed as coatings on the postharvest quality of 'Ortanique' mandarins was also studied. Selected FAs were stearic acid (SA), palmitic acid (PA), and oleic acid (OA), using BW/FA ratios of 1:0.5 and 1:0.2 (w/w). HPMCBW coatings reduced weight and firmness loss of 'Ortanique' mandarins, without compromising flavor quality compared to uncoated mandarins. Coatings containing OA provided the best weight loss control at both concentrations tested; however, when the BW/OA ratio was 1:0.5, the coatings increased fruit internal CO2, ethanol, and acetaldehyde contents of 'Ortanique' mandarins, therefore reducing flavor compared to the rest of the coatings studied. Although barrier and mechanical properties might be used to understand coating performance, differences observed between film oxygen permeability and coating permeability indicate that permeance should be measured on the coated fruit.  相似文献   
78.
Latent phenoloxidase activity of hemocyanin (Hc) in whiteleg shrimp Penaeus vannamei was assayed to determine its potential involvement in postmortem melanosis. Conversion of pure 12-mer, but not 6-mer, hemocyanin to phenoloxidase by endogenous (serine proteinases) and exogenous (SDS) effectors demonstrated the need of complex aggregation for displaying enzyme activity. Because Hc was converted to Hc-phenoloxidase (HcPO) by hemocytes extracts, the mechanism of conversion seems to be the same for polyphenoloxidases. HcPO has similar biochemical and kinetic properties as real polyphenoloxidases and uses mono- and diphenols as substrates. The kinetics of hydroxygenation of monophenols has a lag phase, typical for tyrosinases, contrary to oxidation of diphenols. Regardless of the structure of the substrate, melanin is finally formed. Because of the abundance, distribution, and resistance of Hc to freezing-thawing, involvement of Hc in black spot formation postmortem is suggested. This has important implications for commercialization of shrimp and related seafood.  相似文献   
79.
The phenolic fraction of virgin olive oil influences both its quality and oxidative stability. One of the principal threats of the quality of olive fruit is the olive fly ( Bactrocera oleae) as it alters the chemical composition. The attack of this olive pest has been studied in order to evaluate its influence on the quality of virgin olive oil (free acidity, peroxide value, fatty acid composition, water content, oxidative stability, phenols, and antioxidant power of phenolic fraction). The study was performed using several virgin olive oils obtained from olives with different degrees of fly infestation. They were acquired in different Italian industrial mills from the Abruzzo region. Qualitative and quantitative analyses of phenolic profiles were performed by capillary electrophoresis-diode array detection, and electrochemical evaluation of the antioxidant power of the phenolic fraction was also carried out. These analyses demonstrated that the degree of fly attack was positively correlated with free acidity ( r = 0.77, p < 0.05) and oxidized products ( r = 0.58, p < 0.05), and negatively related to the oxidative stability index ( r = -0.54, p < 0.05) and phenolic content ( r = -0.50, p < 0.05), mainly with secoiridoid compounds. However, it has been confirmed that the phenolic fraction of olive oil depends on several parameters and that a clear correlation does not exist between the percentages of fly attack and phenolic content.  相似文献   
80.
The purpose of this work was to analyze the effect of water on thermal transitions, mechanical properties, and molecular mobility in corn flakes (CF), and their relationships. Commercial common (CCF) and sugar-frosted (SCF) corn flakes were studied in a water content (wc) range from 5 to 20 (% dry basis). The slope of (1)H NMR spin-spin relaxation time T 2* (determined by FID) versus temperature plot changed close to T g. Compression force showed a maximum at wc of ca. 12 and 16% (db) for SCF and CCF, respectively. (1)H NMR complemented DSC data in determining the temperature dependence of water and solid mobility, in order to assess quality of laminated corn products. The results of the present work indicate that while the compression force showed a maximum value as a function of water content, T g values determined by DSC or by spin-spin relaxation decreased progressively with increasing water content.  相似文献   
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