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111.
In this study, experimental canarypox virus (ALVAC) and plasmid DNA recombinant vaccines expressing the gB, gC and gD glycoproteins of EHV-1 were assessed for their ability to protect conventional ponies against a respiratory challenge with EHV-1. In addition, potential means of enhancing serological responses in horses to ALVAC and DNA vaccination were explored. These included co-administration of the antigen with conventional adjuvants, complexation with DMRIE-DOPE and co-expression of the antigen along with equine GM-CSF. Groups of EHV primed ponies were vaccinated twice intra-muscularly with one dose of the appropriate test vaccine at an interval of 5 weeks. Two to 3 weeks after the second vaccination, ponies were infected intra-nasally with the virulent Ab4 strain of EHV-1 after which they were observed clinically and sampled for virological investigations. The results demonstrated that DNA and ALVAC vaccination markedly reduced virus excretion after challenge in terms of duration and magnitude, but failed to protect against cell-associated viremia. Noteworthy was the almost complete absence of virus excretion in the group of ponies vaccinated with ALVAC-EHV in the presence of Carbopol adjuvant or DNA plasmid formulated with aluminium phosphate. The administration of the DNA vaccine in the presence of GM-CSF and formulated in DMRIE-DOPE and of the ALVAC vaccine in the presence of Carbopol adjuvant significantly improved virus neutralising antibody responses to EHV-1. These findings indicate that DNA and ALVAC vaccination is a promising approach for the immunological control of EHV-1 infection, but that more research is needed to identify the immunodominant protective antigens of EHV-1 and their interaction with the equine immune system.  相似文献   
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OBJECTIVE: To describe the microanatomic features of pancreatic islets and the immunohistochemical distribution of glucose transporter (GLUT) molecules in the pancreas and other tissues of New World camelids. ANIMALS: 7 healthy adult New World camelids, 2 neonatal camelids with developmental skeletal abnormalities, and 2 BALB/c mice. PROCEDURE: Samples of pancreas, liver, skeletal muscle, mammary gland, brain, and adipose tissue were collected postmortem from camelids and mice. Pancreatic tissue sections from camelids were assessed microscopically. Sections of all tissues from camelids and mice (positive control specimens) were examined after staining with antibodies against GLUT-1, -2, -3, and -4 molecules. RESULTS: In camelids, pancreatic islets were prominent and lacked connective tissue capsules. Numerous individual endocrine-type cells were visible distant from the islets. Findings in neonatal and adult tissues were similar; however, the former appeared to have more non-islet-associated endocrine cells. Via immunostaining, GLUT-2 molecules were detected on pancreatic endocrine cells and hepatocytes in camelids, GLUT-1 molecules were detected on the capillary endothelium of the CNS, GLUT-3 molecules were detected throughout the gray matter, and GLUT-4 molecules were not detected in any camelid tissues. Staining characteristics of neonatal and adult tissues were similar. CONCLUSIONS AND CLINICAL RELEVANCE: In New World camelids, microanatomic features of pancreatic islets are similar to those of other mammals. Data suggest that the poor glucose clearance and poor insulin response to hyperglycemia in adult camelids cannot be attributed to a lack of islet cells or lack of GLUT molecules on the outer membrane of those cells.  相似文献   
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Fire blight caused by the gram-negative bacterium Erwinia amylovora is a major disease of pome fruit like apple (Malus domestica) or pear (Pyrus communis). Detection of the pathogen is hampered by low titres usually being present during initial flower infection and the brief time frame for analysis to decide upon subsequent countermeasures. Here we describe a loop-mediated isothermal amplification of DNA (LAMP) assay for genomic DNA of Erwinia amylovora, which relies on a highly specific primer design that excludes amplification from typical DNA sources of the orchard biological system and from sample handling. The assay enables the fast detection of down to approximately 20?cfu of pure Erwinia amylovora or 100?fg genomic DNA (corresponding to approximately 25 E. amyolovora equivalents) per reaction within 45?min. Fast and reliable detection of E. amylovora in orchard samples by naked eye is achieved through a visual colour change indication with hydroxynaphthol blue. The assay avoids use of complex technical devices and is thus suitable for field testing.  相似文献   
114.
The stable carbon isotope ratio of atmospheric CO(2) (δ(13)C(atm)) is a key parameter in deciphering past carbon cycle changes. Here we present δ(13)C(atm) data for the past 24,000 years derived from three independent records from two Antarctic ice cores. We conclude that a pronounced 0.3 per mil decrease in δ(13)C(atm) during the early deglaciation can be best explained by upwelling of old, carbon-enriched waters in the Southern Ocean. Later in the deglaciation, regrowth of the terrestrial biosphere, changes in sea surface temperature, and ocean circulation governed the δ(13)C(atm) evolution. During the Last Glacial Maximum, δ(13)C(atm) and atmospheric CO(2) concentration were essentially constant, which suggests that the carbon cycle was in dynamic equilibrium and that the net transfer of carbon to the deep ocean had occurred before then.  相似文献   
115.
The sulfur cycle influences the respiration of sedimentary organic matter, the oxidation state of the atmosphere and oceans, and the composition of seawater. However, the factors governing the major sulfur fluxes between seawater and sedimentary reservoirs remain incompletely understood. Using macrostratigraphic data, we quantified sulfate evaporite burial fluxes through Phanerozoic time. Approximately half of the modern riverine sulfate flux comes from weathering of recently deposited evaporites. Rates of sulfate burial are unsteady and linked to changes in the area of marine environments suitable for evaporite formation and preservation. By contrast, rates of pyrite burial and weathering are higher, less variable, and largely balanced, highlighting a greater role of the sulfur cycle in regulating atmospheric oxygen.  相似文献   
116.
This case report describes the disease progression of a male cat with pericardial effusion. Clinical signs (dyspnea, lethargy, and weakness) started very acutely. The initial laboratory profile showed only an increase in alanine aminotransferase enzyme activity. Diagnostic imaging revealed pericardial effusion. Effusion analysis showed a Rivalta-positive, modified transudate. Detection of feline coronavirus antigen in macrophages was negative. General condition and laboratory parameters dramatically worsened within seven days. Therefore, the owners decided to euthanize the cat. Even if effusion variables are macroscopically and microscopically suspicious for FIP, a definitive diagnosis of FIP could only be made by histology (including immunhistochemical staining).  相似文献   
117.
Intoxication with the beta2-agonist Albuterol may lead to immediate signs of beta-adrenergic stimulation like excitation, tachypnea and tachycardia. Furthermore, it typically causes severe hypokalemia, which then leads to muscle weakness and which predisposes to ventricular arrhythmias. We describe a dog where albuterol intoxication caused runs of fast paroxysmal ventricular tachycardia that persisted after normalization of the hypokalemia. Based on a markedly elevated serum troponin I level acute myocardial damage was identified as cause of the tachyarrhythmia. Repeated Troponin I measurements and Holter-ECGs were the means to document complete cure.  相似文献   
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Purpose To describe six cases of conjunctivitis and ulcerative keratitis secondary to plant foreign bodies from weed‐contaminated grass hay which were lodged within the temporal conjunctival fornix in a herd of alpacas. Methods A total of 21 alpacas from the same farm developed blepharospasm and mucopurulent ocular discharge. Six of the 21 were evaluated at the University of Tennessee College of Veterinary Medicine within a 2‐week period. The six animals evaluated received an ophthalmic examination including slit‐lamp biomicroscopy, fluorescein staining, and topical corneal anesthesia for foreign body removal when necessary. Results Six animals had conjunctivitis characterized by hyperemia and mucopurulent discharge. Five animals had superficial ulcerative keratitis with intense corneal neovascularization and edema. In all cases, the keratitis was located at the temporal limbus. Seven plant foreign bodies were observed and were removed following topical corneal anesthesia in five animals. The plant seeds were identified as three common weed species found in orchard grass hay. Complete resolution of all clinical signs was achieved with foreign body removal and medical therapy. Conclusions Fan‐shaped temporal corneal ulcers may signify the presence of conjunctival foreign bodies in alpacas. Plant foreign bodies should be considered in addition to ocular infection when multiple animals of a herd are affected as outbreaks may occur with weed‐contaminated hay.  相似文献   
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