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61.
Schwarz S Böttner A Hafez HM Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Kühn T Luhofer G Richter A Traeder W Waldmann KH Wallmann J Werckenthin C 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):353-361
In-vitro susceptibility testing provides valuable informations for choosing the most suitable antimicrobial agent for the control of bacterial infections in animals. Different diffusion and dilution methods, as conducted according to various approved performance standards, can be used to determine the in-vitro susceptibility of bacterial pathogens. In the present article, problems are discussed which arise from the use of different methods and the difficulty to interpret such results. While most approved performance standards were designed for testing of bacteria from human sources, the NCCLS document M31-A2 exclusively focusses on susceptibility testing of bacteria isolated from animals and--in contrast to all other standards--includes veterinary specific breakpoints for a number of antimicrobial agents used in veterinary medicine. Therefore, performance of in-vitro susceptibility testing of veterinary pathogens should follow the recommendations given in the NCCLS document M31-A2. The microdilution method is recommended as the method of choice for susceptibility testing. The result of a microdilution test is given as the minimum inhibitory concentration (MIC). This value provides a quantitative result which precisely indicates the degree of susceptibility of the tested bacterial strain and in return gives the veterinarian a clear guidance whether therapeutic intervention with the antibiotic in question will be successful. 相似文献
62.
Christiane Guillorit-Rondeau Laurence Malandrin Regine Samson 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(1):99-104
Flagellar antigen specificity was studied for the speciesPseudomonas syringae, P. viridiflava andP. cichorii. After checking their motility, bacteria were reacted against six polyclonal antisera containing anti-O (LPS) and anti-H (flagellar) antibodies by indirect immunofluorescent staining. Two distinct flagellar serotypes (H1 and H2) were described. The distribution of H1 and H2 serotypes was then determined for a collection of 88 phytopathogenicPseudomonas strains. Serotype H1 was possessed byP. syringae pv.aptata (12 strains),P. s. pv.helianthi (2),P. s. pv.pisi (11), andP. s. pv.syringae (13). Serotype H2 was possessed byP. cichorii (2),P. s. pv.delphinii (1),P. s. pv.glycinea (4),P. s. pv.lacrymans (1),P. s. pv.mori (1),P. s. pv.morsprunorum (10),P. s. pv.persicae (1),P. s. pv.phaseolicola (8),P. s. pv.tabaci (10) andP. s. pv.tomato (1).P. viridiflava (5) revealed HI, H2 and untyped flagella. The following isolates were untypable by the H1/H2 system:P. corrugata (3),P. fluorescens (2),P. tolaasii (1). H1/H2 serotypes distribution is not linked toP. syringae O-serogroups. On the other hand, H1/H2 distribution seems remarkably linked to the new genospecies of theP. syringae group.Abbreviations CFBP
French Collection of Phytopathogenic Bacteria, Angers, France
- ICMP
International Collection of Micro-organisms from Plants, Auckland, New-Zealand
- NCPPB
National Collection of Plant Pathogenic Bacteria, Harpenden, Great Britain 相似文献
63.
Werckenthin C Luhofer G Böttner A Gangl A Goossens L Hafez HM Hartmann K Kaske M Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Kühn T Richter A Schulz B Schwarz S Sigge C Traeder W Waldmann KH Jürgen W;Arbeitsgruppe Antibiotikaresistenz der Deutschen Veterinärmedizinischen;Gesellschaft 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(1-2):19-26
The determination of minimum inhibitory concentrations by broth microdilution is recommended as method of choice for susceptibility testing of veterinary bacterial pathogens. Accordingly, broth microdilution is used in veterinary routine diagnostic laboratories at a progressive rate. To reduce the costs of susceptibility testing, it is reasonable to develop widely accepted uniform microtitre plate layouts that are produced in large quantities. Such microtitre plate layouts have already been developed and published for the susceptibility testing of pathogens from food-producing animals. However, a microtitre plate layout, especially designed for the testing of bacteria from dogs and cats, should be available, too. The choice of the antimicrobial agents or combinations of antimicrobial agents to be included in a suitable layout should be based on the following criteria: (1) the approval and availability of an antimicrobial agent or combination of agents, (2) known cross-resistances, and (3) availability of approved clinical breakpoints. The latter point is of particular importance for the choice of the numbers of concentrations per antimicrobial agent tested and the range of test concentrations. Taking into account these aspects, a science-based layout proposal for microtitre plates, which are suitable for routine testing of bacteria from dogs and cats, is presented and discussed. 相似文献
64.
Schaudien D Schwab S Linke S Seeliger F Pauli G Baumgärtner W Herden C 《Veterinary microbiology》2008,132(1-2):171-176
Five dogs and four cats from Germany suffering from encephalitis revealed positive immunoreactivity using two West Nile virus (WNV) specific monoclonal antibodies in brain and in kidney. However, WNV-infection could not be confirmed by additional PCR analyses. This study indicated that positive immunoreactivity for WNV in dogs and cats must be interpreted cautiously and should be confirmed by a second virus-specific technique. 相似文献
65.
66.
Jeryl C. Jones DVM PhD Peter K. Shires BVSc MS Karen D. Inzana DVM PhD D. Phillip Sponenberg DVM PhD Christiane Massicotte DVM MS Walter Renberg DVM MS Alain Giroux DVM 《Veterinary radiology & ultrasound》1999,40(2):108-114
The objective of this study was to evaluate intravenous contrast-enhanced computed tomography as a technique for predicting the within-level location(s) of compressive soft tissues in the canine lumbosacral spine. Pre-operative intravenous contrast-enhanced computed tomography of the L5-S3 vertebral levels was performed in 12 consecutive large breed dogs with lumbosacral stenosis. The images were evaluated for enhancement of soft tissues by two radiologists who were unaware of the surgical findings. For each within-level location (dorsal canal, ventral canal, right lateral recess, left lateral recess) enhancement was classified as present, absent or equivocal. The results were compared with the results of surgical exploration and histopathology of excised tissues. The positive predictive values of intravenous contrast-enhanced computed tomography for compressive soft tissues involving the dorsal canal, ventral canal and lateral recesses were 83%, 100%, and 81% respectively. Negative predictive values for compressive soft tissues involving these locations were 29%, 50%, and 40% respectively. 相似文献
67.
Christiane Tröβe Rune Waagbø Olav Breck Pål A. Olsvik 《Fish physiology and biochemistry》2010,36(4):1217-1225
Analysis of gene expression in the lens is one of the analytical tools employed to investigate cataract formation in Atlantic
salmon (Salmo salar L.). High quality RNA preparations are an essential prerequisite for gene expression analysis. The first aim of the present
study was to investigate the possible effects of two methods of tissue preservation on the quality of RNA extracted from Atlantic
salmon lenses. RNA was extracted from lenses either stored in RNAlater or flash-frozen in liquid nitrogen. Both tissue preservation methods yielded RNA of similarly high quality. The second aim
was to examine if stress related to fish handling and the choice of anaesthesia during the sampling procedure affected gene
expression in the lens. Six sampling procedures were tested on groups of sea water adapted Atlantic salmon smolt. Fish were
either killed instantaneously (control group) or sampled after 30 min anaesthetised with isoeugenol, after 30 min without
anaesthesia, after 120 min anaesthetised with isoeugenol, after 120 min with 15 min anaesthesia with metacaine or after 120 min
without anaesthesia. The expression levels of specific genes, of special interest in the study of molecular mechanisms of
cataractogenesis, were analysed in lenses by real-time RT–PCR. Fish not anaesthetised had significantly increased levels of
heat shock protein 70 (HSP70) mRNA after 30 min compared to the control group. Glutathione reductase (GR) and manganese superoxide
dismutase (Mn-SOD) were expressed at significantly lower levels in groups of Atlantic salmon sampled after 120 min anaesthetised
with isoeugenol or metacaine, and anaesthetised with isoeugenol, metacaine or without anaesthesia, respectively. The same
expression patterns were found in corresponding gill tissues for these two antioxidant genes. In conclusion, preservation
in liquid nitrogen instead of RNAlater is recommended due to practical conditions in RNA extraction. A quick sampling protocol with the use of anaesthetics and
not exceeding 30 min should be preferred to avoid effects of the sampling procedure on lens gene expression in Atlantic salmon. 相似文献
68.
Christiane Felfe Matthias Schemainda Susanne Baldermann Naoharu Watanabe Peter Fleischmann 《茶叶》2013,(4):308-316
Carotenoid cleavage enzymes isolated from Japanese Camellia sinensis leaves (cultivar Yabukita) were used for investigating the structural patterns of carotenoid cleavage enzymes.Fresh tea leaves were used for the isolation of active enzymes and purified to single band stage in SDS PAGE gels after isoelectric focusing.The specific activity of the carotenoid cleavage enzymes was tested and the active fractions selected for further analysis.The sugar content and the amount of phosphate present in the purified enzymes were elucidated by the following methods:Phosphates were detected by phosphatase assays,fluorescence marker kits and ammoniumheptamolybdate complex measurements after incineration of the samples.Sugars were detected in gels using PAS reagent (periodide acid/ Schiff reagent) staining and by GC-MS after hydrolysation of the proteins with trifluoric acid.Phosphorylations as well as glycosylations of the samples could be detected in all cases,thus giving evidence for an increasing phosphorylation level of proteins in Camellia sinensis from spring (1.84 g/mg) to autumn (2.39 g/rg) as well as the presence of at least four different sugars (arabinose,xylose,galactose and ribose).These secondary modifications of the carotenoid cleavage enzymes and their dependency on the harvesting season may well correspond to the changes on the functional level which were detected between spring (Michaelis Constant (Km) =9.45 mol/1) and autumn (K =17.16 mol/l) harvests. 相似文献
69.
Christiane Kramer Mats Fröberg Luz Maria Cisneros Dozal Dachun Zhang Guaciara M. Santos 《Soil biology & biochemistry》2010,42(7):1028-56
Microbial communities in soil A horizons derive their carbon from several potential sources: organic carbon (C) transported down from overlying litter and organic horizons, root-derived C, or soil organic matter. We took advantage of a multi-year experiment that manipulated the 14C isotope signature of surface leaf litter inputs in a temperate forest at the Oak Ridge Reservation, Tennessee, USA, to quantify the contribution of recent leaf litter C to microbial respiration and biomarkers in the underlying mineral soil. We observed no measurable difference (<∼40‰ given our current analytical methods) in the radiocarbon signatures of microbial phospholipid fatty acids (PLFA) isolated from the top 10 cm of mineral soil in plots that experienced 3 years of litterfall that differed in each year by ∼750‰ between high-14C and low-14C treatments. Assuming any difference in 14C between the high- and low-14C plots would reflect C derived from these manipulated litter additions, we estimate that <∼6% of the microbial C after 4 years was derived from the added 1-4-year-old surface litter. Large contributions of C from litter < 1 year (or >4 years) old (which fell after (or prior to) the manipulation and therefore did not differ between plots) are not supported because the 14C signatures of the PLFA compounds (averaging 200-220‰) is much higher that of the 2004-5 leaf litter (115‰) or pre-2000 litter. A mesocosm experiment further demonstrated that C leached from 14C-enriched surface litter or the O horizon was not a detectable C source in underlying mineral soil microbes during the first eight months after litter addition. Instead a decline in the 14C of PLFA over the mesocosm experiment likely reflected the loss of a pre-existing substrate not associated with added leaf litter. Measured PLFA Δ14C signatures were higher than those measured in bulk mineral soil organic matter in our experiments, but fell within the range of 14C values measured in mineral soil roots. Together, our experiments suggest that root-derived C is the major (>60%) source of C for microbes in these temperate deciduous forest soils. 相似文献
70.
Objective To determine the density of the canine and feline corneal neural network in healthy dogs and cats using in vivo confocal microscopy (IVCM). Animals examined A total of 16 adult dogs (9 Mesocephalic breeds, 7 Brachycephalic breeds) and 15 cats (9 Domestic Short-haired cats (DSH), 6 Persian cats) underwent IVCM. Procedure Animals were examined with a confocal corneal microscope (HRTII/RCM; Heidelberg Retina Tomograph II/Rostock Cornea Module®, Heidelberg Engineering, Dossenheim, Germany). The investigations focused on the distribution of the corneal nerves and quantification of central subepithelial and subbasal nerve plexus. Results The corneal stromal nerve trunks, subepithelial and subbasal nerve plexus were observed. The nerve fiber density (NFD) quantified in nerve fiber length in mesocephalic dogs were 12.39 ± 5.25 mm/mm2 in the subepithelial nerve plexus and 14.87 ± 3.08 mm/mm2 in the subbasal nerve plexus. The NFD of the subepithelial nerve plexus in DSH cats was 15.49 ± 2.7 and 18.4 ± 3.84 mm/mm2 in the subbasal nerve plexus. The subbasal NFD of DSH cats was significantly higher than in mesocephalic dogs (P = 0.037). The subepithelial NFD in brachycephalic dogs, and Persian cats were 10.34 ± 4.71 and 9.50 ± 2.3 mm/mm2, respectively. The subbasal NFD measured 11.80 ± 3.73 mm/mm2 in brachycephalic dogs, and 12.28 ± 4.3 mm/mm2 NFD in Persian cats, respectively. The subepithelial and subbasal NFD in Persian cats were significantly lower than in DSH cats (P = 0.028, respectively, P = 0.031), in contrast to brachycephalic vs. mesocephalic dogs. Conclusion The noninvasive IVCM accurately detects corneal innervation and provides a reliable quantification of central corneal nerves. 相似文献