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81.
OBJECTIVE: To evaluate efficacy of cyclosporine A, administered at either of 2 dosages, in dogs with atopic dermatitis (AD). DESIGN: Multicenter randomized controlled trial. ANIMALS: 91 dogs with AD. PROCEDURE: Dogs were assigned to receive placebo (30 dogs), cyclosporine at a low dosage (2.5 mg/kg [1.1 mg/lb], PO, q 24 h for 6 weeks; 30 dogs), or cyclosporine at a high dosage (5.0 mg/kg [2.3 mg/lb], PO, q 24 h for 6 weeks; 31 dogs). RESULTS: After 6 weeks, mean percentage reductions, compared with baseline scores, in scores of lesion severity were 34, 41, and 67% for dogs treated with the placebo, cyclosporine at the low dosage, and cyclosporine at the high dosage, respectively. Similarly, mean percentage reductions in pruritus scores were 15, 31, and 45%, respectively. Percentage reductions in skin lesion and pruritus scores were significantly higher for dogs given cyclosporine at the high dosage than for dogs given the placebo. Treatment efficacy was significantly associated with whether dogs had a history of seasonal AD. Percentage reductions in skin lesion and pruritus scores were high for dogs treated with cyclosporine at the highest dosage that had a history of nonseasonal AD. Dogs in all groups with seasonal AD improved during the study period. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that oral administration of cyclosporine at a dosage of 5.0 mg/kg once daily is effective in reducing severity of pruritus and skin lesions in dogs with AD, especially those with nonseasonal disease.  相似文献   
82.
83.
OBJECTIVE: To compare penetration of IV administered marbofloxacin in intraocular fluids of healthy and inflamed eyes in rabbits with endotoxin-induced endophthalmitis. ANIMALS: 35 pigmented rabbits. PROCEDURES: Endophthalmitis was induced in the right eye via intravitreal administration of Escherichia coli endotoxin. The left eye was a control eye. After 24 hours, a single dose of marbofloxacin (4 mg/kg, IV) was administered. Groups of rabbits (n = 5/group) were euthanized 0.5, 1, 2, 4, 6, 10, and 18 hours later, and blood and ocular fluids were collected. Marbofloxacin concentrations were determined via reverse-phase high-performance liquid chromatography, and pharmacokinetic analysis of the data was performed with a mono-compartmental model. RESULTS: Mean area under the aqueous concentration-time curve was significantly lower in control eyes (1.64 +/- 0.07 microg*h/mL) than in inflamed eyes (3.31 +/- 0.11 microg*h/mL). Similarly, drug penetration into aqueous humor was 33% and 65% for control eyes and inflamed eyes, respectively. Mean area under the vitreous humor concentration-time curve for control eyes(1.75 +/- 0.05 microg*h/mL) was significantly less than for inflamed eyes (2.39 +/- 0.16 microg*h/mL). In the vitreous humor, corresponding penetrations were 34% and 47%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Penetration of marbofloxacin into the aqueous and vitreous humor after IV administration was significantly enhanced by intraocular inflammation, suggesting a role for this antimicrobial in the prophylaxis or treatment of bacterial endophthalmitis caused by susceptible pathogens.  相似文献   
84.
Several theoretical models of the casein micelle structure have been proposed in the past, but the exact organization of the four individual caseins (α(s1), α(s2), β, and κ) within this supramolecular structure remains unknown. The present study aims at determining the topography of the casein micelle surface by following the interaction between 44 monoclonal antibodies specific for different epitopes of α(s1)-, α(s2)-, β-, and κ-casein and the casein micelle in real time and no labeling using a surface plasmon resonance (SPR)-based biosensor. Although the four individual caseins were found to be accessible for antibody binding, data confirmed that the C-terminal extremity of κ-casein was highly accessible and located at the periphery of the structure. When casein micelles were submitted to proteolysis, the C-terminal extremity of κ-casein was rapidly hydrolyzed. Disintegration of the micellar structure resulted in an increased access for antibodies to hydrophobic areas of α(s1)- and α(s2)-casein.  相似文献   
85.
Plant disease complexes are a playground to investigate coinfections in natural or cultivated systems. Pathogens of such complexes may affect each other through direct and/or indirect interactions and lead to changes in virulence or aggressiveness, offspring production, and transmission. As coinfections by sympatric host-pathogens can strongly influence pathogen dynamics and their evolutionary trajectories, new insights into the mechanisms of their coexistence is thus of critical importance. In order to characterize differences in ecological niches liable to explain species coexistence on the same host, the inter- and intraspecific diversity of the life history traits in natural collections of the two main pathogens (Peyronellaea (formerly Didymella) pinodes [Dp] and Phoma medicaginis var. pinodella [Pmp]) of the ascochyta blight disease complex of pea was evaluated under controlled conditions. Dp strains developed 1.3 times faster and produced longer, mainly bicellular spores and in lower amounts (3.7 times less) than Pmp strains. Pmp strains were separated into two groups, one producing more pycnidiospores, mainly bicellular, with less resources, and the other with mainly unicellular ones. These three groups can be interpreted as three distinct life history strategies: pioneer colonizer (Dp), scavenger (large-spored Pmp), and intermediate (small-spored Pmp), allowing differentiation in access to and use of resources. While this experimental work provides new insight into coexistence of two species of the ascochyta blight disease complex of pea, it also raises the question of the benefit of having two distinct life history strategies for one species (Pmp).  相似文献   
86.
Thirty isolates of Magnaporthe grisea collected from 18 provinces/cities representing 21 pathotypes and 9 different lineages were inoculated to rice varieties with known resistance genes and some hybrid rices,conventional early indica and late japonica varieties cultivated recently in China.Virulence spectrum of the 30 isolates was very different,showing that they recognize numerous different resistance genes.Varieties also revealed very different resistance patterns showing that they carry different resistance genes or combinations of resistance genes.On the basis of comparisons with international differential varieties with known resistance genes,resistance genes in certain Chinese varieties could be speculated.The results indicated that some of them were resistant to most of the isolates tested and that they could be of interest as resistance sources for hybrid parents or to be planted in the field directly.  相似文献   
87.
Deliberate and malevolent use of plant pathogens, i.e. agroterrorism lato sensu (anticrop bioterrorism and use of bioweapons against the agricultural sector), may represent a non-negligible threat for crops and forests in Europe. In order to assess this risk objectively, a methodology based on a critical review of existing Pest Risk Analysis schemes has been elaborated and is described in the present paper. In this methodology, three interdependent steps are suggested: (i) definition of an a priori list of potentially dangerous plant pathogens for Europe, (ii) detailed elaboration and analysis of theoretical scenarios of possible acts of agroterrorism, and (iii) elaboration and use of a risk assessment scheme adapted to agroterrorism.  相似文献   
88.
The aim of this work was to measure the myeloperoxidase (MPO) concentration in bronchoalveolar lavage (BAL) fluid collected from horses with recurrent airway obstruction (RAO), both in crisis and in remission, as well as from healthy horses. Seven horses with RAO were exposed to moldy hay until the maximum change in pleural pressure was greater than 1.5 kPa. At that point, BAL was performed, and the total cell counts and percentages in the fluid were immediately determined. To measure the MPO concentration in BAL-fluid supernatant, we used a specific enzyme-linked immunosorbent assay with polyclonal antibodies against equine MPO. The tests were repeated on the horses with RAO after they had spent 2 mo on pasture. Six healthy horses serving as controls underwent the same tests. The absolute and relative neutrophil counts and the MPO concentration in the BAL fluid were significantly greater in the horses with an RAO crisis than in the control horses. After 2 mo on pasture, the horses that had been in RAO crisis were clinically normal, and their neutrophil counts and MPO levels in BAL fluid had significantly decreased; during remission their neutrophil counts were not significantly different from those in the healthy horses, but their MPO concentration remained significantly higher. This study showed that determining the MPO concentration in a horse's BAL fluid is technically possible and that during remission from RAO the concentration remains higher than normal. Thus, MPO may be a marker of neutrophil presence and activation in the lower airways.  相似文献   
89.
Dairy industries are interested in knowing the heat treatment undergone by milk so as to control the quality of drinking milks or to control their heating systems. Among the different techniques available to characterize the heat treatment of milk, estimation of the denaturation of proteins has been widely used. However, because the concentration of the proteins in raw milk can fluctuate significantly, determining only the concentration of a native protein without knowing its concentration in the raw milk before undergoing heat treatment can lead to significant imprecision. The objective of this study was to develop, on Biacore 3000, a biosensor assay for determining the denaturation index of alpha-lactalbumin by quantifying separately the native and "heat-denatured" forms of alpha-lactalbumin with specific monoclonal antibodies. alpha-Lactalbumin denaturation index is independent of the concentration of alpha-lactalbumin in the original raw milk. The technique developed is discriminating, fast, repeatable, fully automated, and requires no pretreatment of the milk sample.  相似文献   
90.
Six isolates of Magnaporthe grisea were selected to inoculate on 10 Chinese leading maintainer lines (B-lines), 14 restorer lines (R-lines) and their F1 hybrid plants. In the tested rice materials, R-lines were proved to be more resistant to blast than B-lines. The resistance frequency of about 25% F1 hybrid plants was less than their parents. In addition, 26 isolates of M. grisea collected from different rice growing areas of China were inoculated on 13 new improved hybrid rice combinations. The resistance frequencies of 5 improved hybrids were better than those of the controls and leading varieties in rice production of China.  相似文献   
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