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91.
Under physiological conditions canines transport vitamin A in blood plasma primarily as retinyl esters bound to lipoproteins and excrete substantial amounts of vitamin A as retinol and retinyl esters with urine. In the aqueous environment of urine, the hydrophobic vitamin A has to be associated with a protein. This vitamin A-protein complex was purified to homogeneity, prepared by preparative ultracentrifugation (density 1.21 g/mL), native polyacrylamide gel electrophoresis (PAGE) and size exclusion chromatography. The vitamin A-protein complex has a high molecular mass of > 5,000 kDa under native conditions. SDS PAGE under reduced conditions revealed a single band with a molecular mass of about 100 kDa for the protein moiety. Peptides obtained after limited proteolysis with trypsin from the 100 kDa protein were characterised by MALDI-TOF mass spectrometry and showed amino acid sequence homology to the human Tamm-Horsfall Protein (THP). This was further confirmed by a positive immunoreaction of the isolated protein with crossreacting human THP antibodies. The localisation of THP in dog kidneys was determined by using immunohistology. The reaction was strong along the entire thick ascending limb ofthe Henle loop and distal convoluted tubule. Our data point to the possibility that THP functions as a novel carrier for vitamin A in the urine of canines.  相似文献   
92.
Twelve monoclonal antibodies (MAbs) were obtained by immunizing mice with a French isolate (F1) of wheat yellow mosaic virus (WYMV). Three of these (3D12, 2C1, 6C3) belong to the IgM class and the nine others to the IgG class (3D8, 3H1, 2B8, 1F2, 3C10, 4F12, 3H9, 1G5, 54). In antigen-coated plate (ACP) ELISA and indirect double antibody sandwich (IDAS) ELISA, all MAbs recognize the WYMV (F1) both in the form of purified particles and in wheat leaf extract. The analysis of numerous French isolates of WYMV shows a variable reactivity with MAbs 3D8, 3H1, 2B8, 3C10, 3H9 and 1G5 in IDAS — and ACP-ELISA. The Japanese isolate of WYMV and United States isolates of wheat spindle streak mosaic virus (WSSMV) were detected in IDAS- and ACP-ELISA by ten of the MAbs tested showing that the wheat bymoviruses originating from the three locations share a high epitopic homology. French isolates of barley yellow mosaic virus (BaYMV; pathotypes 1 and 2) were only detected in ACP-ELISA with MAbs 6C3, 3D8, 3H1 and 2B8 whereas the two Japanese strains (I-1, II-1) of MaYMV were recognized with these and also with that of 3C10. In IDAS-ELISA, the two Japanese strains were clearly detected by MAbs, 6C3, 3D8, 3H1, 1F2, 3C10 and 1G5 and the British and Belgian (pathotype 2) isolates only by that of 6C3. Only the Japanese strain of BaYMV, 1-1 could be detected with MAb 3H9 in this ELISA system.  相似文献   
93.
OBJECTIVE: To determine clinical characteristics, treatments, and outcome in dogs and cats evaluated after submersion in freshwater. DESIGN: Retrospective case series. ANIMALS: 25 dogs and 3 cats. PROCEDURES: Medical records were reviewed for signalment; causes, location, and month of submersion; physical examination findings at admission; results of blood gas analysis; treatments administered; duration of hospitalization; and outcome, including evidence of organ failure or compromise. RESULTS: All submersions involved bodies of freshwater. Fourteen animals were submerged in man-made water sources, 13 were submerged in natural water sources, and the body of water was not recorded in 1 case. Twenty (71%) submersions occurred from May through September. Cause was identified in 16 animals and included extraordinary circumstances (n = 6), falling into water (5), breaking through ice (3), and intentional submersion (2). Twelve animals were found submerged in water with unclear surrounding circumstances. Treatment included administration of supplemental oxygen, antimicrobials, furosemide, corticosteroids, and aminophylline and assisted ventilation. Respiratory dysfunction was detected in 21 animals. Neurologic dysfunction was detected in 12 animals, hepatocellular compromise was detected in 6 animals, and cardiovascular dysfunction was detected in 4 animals. Three dogs had hematologic dysfunction, and 2 dogs had acute renal dysfunction. Eighteen (64%) animals survived to hospital discharge, but all of the cats died. In 9 of 10 nonsurvivors, respiratory tract failure was the cause of death or reason for euthanasia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that submersion is an uncommon reason for veterinary evaluation but is associated with a good prognosis in dogs in the absence of respiratory tract failure.  相似文献   
94.
Actinobacillus pleuropneumoniae, a gram-negative rod of the Pasteurellaceae family, causes pleuropneumonia in pigs. Establishing A. pleuropneumoniae free herds is difficult due to the occurrence of persistently infected animals. The ApxIV toxin is expressed by A. pleuropneumoniae in vivo and an ELISA based on the toxin is used to detect infection and to differentiate between infected and vaccinated animals. In this study, we have identified a 1070bp insertion element of the IS30 family, designated ISApl1, in the A. pleuropneumoniae serotype 7 strain AP76. ISApl1 contains a 924bp ORF encoding a transposase, which is flanked by 27bp inverted repeats showing six mismatches. We investigated the occurrence of ISApl1 in other A. pleuropneumoniae strains, and its possible interference with virulence associated factors. Four insertion sites were identified in AP76: within the apxIVA toxin ORF, within a putative autotransporter adhesin ORF, upstream of a capsular polysaccharide biosynthesis gene cluster, and downstream of a beta-lactamase gene. ISApl1 is also present in some serotype 7 field isolates, but not in reference or field strains of other serotypes. In A. pleuropneumoniae AP76, the transposase gene is transcribed in vitro. The insertion in the apxIVA toxin gene remains stable after animal passage. Since this insertion should disrupt toxin expression, we tested 7 pigs infected with AP76 at day 21 post-infection. All were negative in the ApxIV ELISA but four out of seven were positive in an ApxII toxin ELISA. These results show that insertion elements can affect the detection of A. pleuropneumoniae infected animals.  相似文献   
95.
Nephrolithiasis has rarely been reported in marine mammals. During 2004 and 2005, two cases of nephrolithiasis were diagnosed during routine necropsy examination, one in a northern elephant seal (Mirounga angustirostris) and one in a California sea lion (Zalophus californianus). Nephroliths were found throughout both kidneys during necropsy examination, varying in size from 1-10 mm in diameter in the northern elephant seal and from 1-15 mm in diameter in the California sea lion. Necropsy and histopathology revealed nephroliths in association with renal pelvic dilation and pyelonephritis in both animals. In addition, hydronephrosis was noted in the sea lion. Nephroliths were composed of uric acid and ammonium urate in the northern elephant seal and of ammonium urate in the California sea lion. The underlying disease leading to nephrolith formation was not determined; however, it is hypothesized that unknown metabolic derangements due to morphologic or physiologic differences may have played a role. This is the first report of urate nephrolithiasis in the California sea lion and northern elephant seal.  相似文献   
96.
97.
Little is known about the safety and efficacy of extra-label use of the modified live porcine reproductive-and-respiratory syndrome (PRRS) virus vaccine in gestating sows. Our purpose was to determine the impact of vaccination on reproductive performance in 54 herds in Ontario, Manitoba (Canada) and the mid-western United States that were PRRS-positive, PRRS-negative, or concurrently affected by an outbreak of PRRS when initially vaccinated. Majority-vaccinated herds vaccinated ≥50% but <100% of sows at one time, and limit-vaccinated herds vaccinated <50% of sows at one time. Most majority-vaccinated herds did not vaccinate sows in late gestation, and none vaccinated during the initial PRRS outbreak. Numbers of pigs born alive and weaned decreased when pregnant sows were vaccinated. The effect of vaccination on productivity in the gestation following vaccination depended on the vaccination protocol.  相似文献   
98.
99.
Campylobacter are a leading cause of human diarrhea. The usual source of infection is contaminated food, particularly poultry but pork has also been described. The veterinary use of antimicrobial drugs has been suggested to be largely responsible for resistance in human isolates of this zoonotic pathogen. A study was carried out to investigate the occurrence and antimicrobial resistance of Campylobacter isolated from French fattening pigs. From March 1998 to June 1999, stomach samples were collected at slaughter from 240 fattening pigs originating from 24 different farms. Half of the pigs were found to be positive for Campylobacter but considerable variation was observed between farms. Isolates all belong to the Campylobacter coli species. Susceptibilities of the strains were determined for five antimicrobial drugs using agar dilution. Resistance to tetracycline and erythromycin was high (79 and 55%, respectively). For nalidixic acid, enrofloxacin and ampicillin, resistance was observed in 34, 15 and 20% of the isolates, respectively. More than one-third of the strains was resistant to at least three antimicrobial drugs. A Thr86Ile modification in GyrA was observed in the enrofloxacin-resistant strains studied. The multiresistant strains analyzed expressed the multidrug transporter CmeB at a high level. Results indicated a high prevalence of C. coli in the stomach of the French pigs examined. In addition, a high proportion of the strains was resistant to antimicrobial drugs, particularly to tetracycline and erythromycin, or were multiresistant.  相似文献   
100.
Acibenzolar-S-methyl (Novartis) is a chemical inducer of systemic acquired resistance in several annual plants. The ability of this novel chemical to induce resistance was studied in a perennial plant (apple) affected by fire blight caused by Erwinia amylovora. Acibenzolar-S-methyl (100 and 200mg/l active ingredient) protected Golden Delicious seedlings, scions and trees from artificial infection when applied before inoculation. The protection of apple seedlings was similar to the protection obtained with the standard for fire blight control, plantomycin (100mg/l streptomycin sulfate), applied immediately before inoculation. The mean levels of control in scions in the greenhouse and in trees in orchards were approximately 69% and 50%, respectively. The protection of apple seedlings was constantly associated with the activation of two families of defense-related enzymes, peroxidases and -1,3-glucanases. Accumulation of both enzymes was induced locally in treated leaves and systemically, especially for -1,3-glucanases, in upper untreated leaves, and was sustained for at least 17 days. These results suggest that acibenzolar-S-methyl promotes induced systemic resistance in apple by increasing defense-related compounds. This chemical could provide a new approach of control of fire blight but its practical use needs further investigation.  相似文献   
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