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51.
52.
Chang CH Lee-Fowler TM Declue AE Cohn LA Robinson KL Reinero CR 《Veterinary immunology and immunopathology》2011,144(3-4):437-441
Glucocorticoids (GCs) are palliative for allergic asthma, but allergen-specific immunotherapy (ASIT), which relies on identification of allergens, represents a potentially curative treatment. The purpose of this study was to determine if oral or inhaled GCs would interfere with identification of sensitizing allergens. The hypothesis was that oral but not inhaled GCs would interfere with accurate allergen-specific IgE identification determined by skin and serum testing in experimentally asthmatic cats. Asthma was induced in 18 cats using Bermuda grass allergen (BGA). Cats (n=6/group) were randomized to receive oral GCs (10mg prednisolone q 24 h), inhaled GCs (600 μg budesonide q 24 h) or placebo (q 24 h PO) for one month. Intradermal skin testing (IDST) and serum BGA-specific IgE were measured prior to, during and after treatment. A paired t test was used to compare groups pre- and post-treatment (P<0.05 significant). IDST reactivity was eliminated in 4/6, 3/6, and 1/6 cats receiving oral GCs, inhaled GCs, and placebo respectively. Two weeks after stopping treatment, IDST was again positive in all cats. Serum IgE reactivity to BGA was not significantly diminished by any treatment. In conclusion, a two-week withdrawal from GCs is adequate for IDST, but may not be necessary for serum IgE testing. 相似文献
53.
Wetland plants have a capacity for metal sequestration and have been used to remediate such environmental contaminants. How this capacity will be affected by a warming environment is not well-known. Our objective was to identify the effect of small environmentally realistic increases in temperature on metal (cadmium, zinc, lead, and copper) accumulation in Typha latifolia as compared with Scirpus acutus. These common wetland plant species were grown in metal-contaminated sediments at 13??C, 16??C, and 18??C for 3?months to determine the effect of environmentally realistic temperatures on metal accumulation. Cd109 was used as a radiotracer to study the effect of temperature on uptake kinetics. Growth of the two wetland plants differed markedly; S. acutus displayed linear growth reaching a maximum height of ca. 100?cm; by contrast, T. latifolia grew to ca. 40?cm by day?60 with no further growth occurring over the remainder of the 105-day growth period. S. acutus accumulated more cadmium, lead, and zinc from contaminated sediments than T. latifolia, but only within roots and rhizomes. Although not significant, uptake of cadmium, lead, and zinc by both plants was enhanced under warmer conditions and was most pronounced in S. acutus. This was supported by the radiotracer studies which indicated that under the higher temperatures, there was increased rates of Cd109 uptake by shoots of S. acutus. By contrast, temperature did not affect Cd109 uptake rate constants in T. latifolia. S. acutus appears to be more effective at sequestering metals from contaminated sediments; this species as compared to T. latifolia may also be more affected by a warming climate. In the design of wetlands for metal remediation, differences in how these two plants sequester metals from their environment should be considered. 相似文献
54.
Marcel Maymon Gunjan Sharma Marina Hazanovsky Orly Erlich Shir Pessach Stanley Freeman Leah Tsror 《Plant pathology》2021,70(4):793-803
Fusarium wilt, caused by Fusarium oxysporum, is a major disease of jojoba, causing serious economic losses. This study was aimed at characterizing the Fusarium populations associated with jojoba in Israel. Fifty Fusarium isolates used in this study included 23 isolates from the 1990s (“past”) and 27 recently isolated (“recent”). All the isolates were characterized by arbitrarily primed (ap)-PCR and 16 representatives were additionally delineated using multilocus (tef1, rpb1, rpb2) phylogeny and evaluated for their pathogenic potential. Consequently, 88% of the isolates were identified and characterized to the F. oxysporum species complex. The remaining 12% grouped within the F. fujikuroi, F. solani, and F. redolens species complexes. Variations in the infection rate (16.7%–100%), disease symptoms (0.08–1.25, on a scale of 0–3), and fungal colonization index (0.67–2.17, on a scale of 0–4) were observed within the tested isolates, with no significant differences between the past and recent isolates. The representative isolates were assigned to 11 groups based on ap-PCR. Pathogenicity tests showed that isolates from Groups II, IV, and V were the most aggressive, whereas isolates from Groups III, VIII, and IX were the least aggressive. Among the tested isolates, F. oxysporum sensu lato was the most aggressive, followed by F. proliferatum, while F. nygamai was the least aggressive. This study demonstrates the complexity and genetic diversity of Fusarium wilt on jojoba in Israel, indicating possible multiple introductions of infected germplasm into the country. 相似文献
55.
Leah Tsror Valerie Hélias Sara Mordechai-Lebiush Orly Erlich Marina Hazanovsky Laura Chalupowicz Michal Reuven Orit Dror Lea Valinsky Angelique Laurent Shulamit Manulis-Sasson 《Plant pathology》2021,70(9):2179-2187
Pectobacterium brasiliense (Pbr) infects a wide range of crops worldwide, causing potato blackleg and soft rot and vegetable soft rots. This study aimed to characterize the genetic diversity and virulence variability among 68 Pbr strains isolated from either symptomless potato progeny tubers, diseased potato plants, ware potatoes wash water, or vegetables grown in Israel, as well as strains isolated from symptomless seed tubers grown in Europe, or diseased potato plants grown in France. The collection was typed using PCR and TaqMan real-time PCR analyses, dnaX sequence analysis, pulsed-field gel electrophoresis (PFGE), and pectolytic activity. dnaX phylogeny grouped almost all strains in a common genetic clade related to Pbr, which was distinct from the other Pectobacterium species. PFGE analysis identified two main clusters, including one major group of 47 strains with 95%–100% similarity. Maceration assays on two potato cultivars showed significant differences between strains but with no correlations with the source of the strains nor the status of the host (with/without symptoms). Molecular (dnaX sequences and PFGE profiles) and phenotypic analyses (tuber maceration tests) showed that the tested Pbr strains are not a homogeneous group. Analysis of the tested Pbr strains isolated from potato and vegetables grown in fields with a history of potato cultivation suggests that seed tubers imported from Europe may be the main source for Pbr in Israel. To the best of our knowledge, this is the first study that describes biodiversity and population structure of P. brasiliense isolated from potato and vegetables under hot climate conditions. 相似文献
56.
The official final action acid hydrolysis method, 14.019, for the determination of fat in foods was successfully applied, with slight modifications, to the analysis of homogenates of food, feces, and animal tissues as well as dry samples of mixed foods. In samples containing sucrose or fructose, it was necessary to carry out a fermentation procedure before acid hydrolysis to avoid problems encountered when these sugars were present. 相似文献
57.
Leah Estberg Ian A. Gardner Susan M. Stover Bill J. Johnson James T. Case Alex Ardans 《Preventive veterinary medicine》1995,24(4):253-263
Thoroughbred racehorses which suffered a fatal musculoskeletal injury (FMI) while racing or race training at a California racetrack during 9 months of 1991 were studied to determine the importance of intensive, high-speed exercise schedules prior to injury. Seventy-seven horses which sustained an FMI while racing and 45 horses which sustained an FMI while race training were successfully matched by race or timed workout session with one control horse and included in the analyses. Race and timed workout (racing-speed exercise) histories were obtained for the case and control horses. Two-month cumulative, racing-speed cutoff distances were calculated from the control horse sample by two methods. Median racing-speed exercise frequencies and distances of the control horses were used to estimate age-specific (2, 3, 4 and ≥ 5 years), 2-month cumulative, racing-speed distances (Method 1). For the second method, the last race or timed workout for each control horse occurring just prior to, or on the date of injury for the matched case horse was identified. Cumulative racing-speed distances 2 months prior to these exercise events were determined for each control horse and used to estimate median age-specific (2, 3, 4 and ≥ 5 years), 2-month cumulative racing-speed distances (Method 2). The cumulative cutoff distances estimated from both methods were used to classify each matched pair according to the presence or absence of a 2-month cumulative, racing-speed distance which exceeded the age-appropriate cutoff distance (exercise distance cluster) within 6 months prior to injury. Manlel-Haenszel matched-pair odds ratios and 95% confidence limits were calculated separately for the racing and race-training fatal injuries. The relative risk for racing FMI was significantly greater for those horses which ran 2-month, cumulative racing and timed workout distances in excess of the cutoff values determined with Method 1 (relative risk (RR) = 3.0, 95% confidence interval (CI) = 1.2, 7.6) and Method 2 (RR = 7.2, 95% CI = 2.6, 20.6). The relative risk for race-training FMI was significantly greater for those horses which ran 2-month, cumulative racing and timed workout distances in excess of the cutoff values determined with Method 2 (RR = 3.4, 95% CI =1.0, 13.2). 相似文献
58.
Leah A Cohn 《Veterinary Clinics of North America: Small Animal Practice》2003,33(4):863-884
Ehrlichiosis is a term that has been used to describe infection with any of a number of related intracellular, vector-borne pathogens. A recent reclassification has resulted in the transfer of several species previously known as Ehrlichia to the genus Anaplasma or Neorickettsia. Ehrlichia and Anaplasma are transmitted largely through the bite of infected ticks, while vectors for Neorickettsia include trematodes and the intermediate hosts (i.e., fish, snails, and insects) involved in the trematode life cycle. Dogs (and cats) are susceptible to infection with several of these pathogens, and veterinarians should be aware of the similarities and differences between E canis and related infections. Pets with suggestive clinical signs and laboratory abnormalities may be started on doxycycline pending specific diagnostic testing. The veterinarian practicing in endemic areas must understand the implications and limitations of serologic and molecular testing to confirm a diagnosis. For animals in endemic areas, prevention of exposure to vectors can lessen the risk of disease for pets and might lessen the potential for animals to become carriers of disease for their human companions. 相似文献
59.
60.
Two glucosyltransferases capable of glucosylating the primary major bentazone metabolite, 6-hydroxybentazone, have been isolated from tolerant soybean (Glycine max (L.) Fiskerby V) tissue. A soluble flavonol glucosyltransferase, whose primary substrate was kaempferol, was isolated from 3-week-old light-grown tissue. This enzyme had a relative molecular mass of 44 600, a pH optimum of 6·3 and Michaelis constants for kaempferol and 6-hydroxybentazone of 0·09 and 2·45 mM respectively. A membrane-bound glucosyltransferase whose primary substrate was the intermediate shikimic acid metabolite, p-hydroxyphenylpyruvic acid, was also isolated from 7-day-old etiolated tissue. This enzyme had a relative molecular mass of 53000 (which could be dissociated to approximately 28000), a pH optimum of 7·5 and Michaelis constants for p-hydroxyphenylpyruvic acid and 6-hydroxybentazone of 0·11 and 1·96 mM respectively. These results suggest that 6-hydroxybentazone, and possibly many other hydroxylated pesticides, may be further detoxified by several glucosyltransferases with overlapping specificity whose primary role involves the storage of endogenous metabolites. 相似文献