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111.
Siao KT Pypendop BH Stanley SD Ilkiw JE 《Journal of veterinary pharmacology and therapeutics》2011,34(6):599-604
Siao, K. T., Pypendop, B. H., Stanley, S. D., Ilkiw, J. E. Pharmacokinetics of amantadine in cats. J. vet. Pharmacol. Therap. 34 , 599–604. This study reports the pharmacokinetics of amantadine in cats, after both i.v. and oral administration. Six healthy adult domestic shorthair female cats were used. Amantadine HCl (5 mg/kg, equivalent to 4 mg/kg amantadine base) was administered either intravenously or orally in a crossover randomized design. Blood samples were collected immediately prior to amantadine administration, and at various times up to 1440 min following intravenous, or up to 2880 min following oral administration. Plasma amantadine concentrations were determined by liquid chromatography–mass spectrometry, and plasma amantadine concentration–time data were fitted to compartmental models. A two‐compartment model with elimination from the central compartment best described the disposition of amantadine administered intravenously in cats, and a one‐compartment model best described the disposition of oral amantadine in cats. After i.v. administration, the apparent volume of distribution of the central compartment and apparent volume of distribution at steady‐state [mean ± SEM (range)], and the clearance and terminal half‐life [harmonic mean ± jackknife pseudo‐SD (range)] were 1.5 ± 0.3 (0.7–2.5) L/kg, 4.3 ± 0.2 (3.7–5.0) L/kg, 8.2 ± 2.1 (5.9–11.4) mL·min/kg, and 348 ± 49 (307–465) min, respectively. Systemic availability [mean ± SEM (range)] and terminal half‐life after oral administration [harmonic mean ± jackknife pseudo‐SD (range)] were 130 ± 11 (86–160)% and 324 ± 41 (277–381) min, respectively. 相似文献
112.
DiMaio Knych HK Arthur RM Taylor A Moeller BC Stanley SD 《Journal of veterinary pharmacology and therapeutics》2011,34(3):238-246
Dantrolene is a skeletal muscle relaxant used commonly in performance horses to prevent exertional rhabdomyolysis. The goal of the study reported here was to begin to characterize cytochrome P450-mediated metabolism of dantrolene in the horse and describe the pharmacokinetics of the compound, formulated as a capsule or a compounded paste formulation, following oral administration. Dantrolene is rapidly metabolized to 5-hydroxydantrolene both in vivo and in vitro. Preliminary work with equine liver microsomes suggest that two enzymes are responsible for the metabolism of dantrolene, as evidenced by two distinct K(m) values, one at high and one at low substrate concentrations. For the pharmacokinetic portion of the study, a randomized, balanced 2-way crossover design was employed wherein eight healthy horses received a single oral dose of either capsules or paste followed by a 4 week washout period prior to administration of the second formulation to the same horse. Blood samples were collected at time 0 (prior to drug administration) and at various times up to 96 h postdrug administration. Plasma samples were analyzed using liquid chromatography-mass spectrometry and data analyzed using both noncompartmental and compartmental analysis. Peak plasma concentrations were 28.9 ± 21.6 and 37.8 ± 12.8 ng/mL for capsules and paste, respectively and occurred at 3.8 h for both formulations. Dantrolene and its major metabolite were both below the limit of detection in both plasma and urine by 168 h postadministration. 相似文献
113.
A total of 763 faecal samples were collected from western grey kangaroos (Macropus fuliginosus) in Western Australia and screened for the presence of Cryptosporidium by PCR at the 18S ribosomal RNA (rRNA) locus. Samples that were positive at the 18S locus were also amplified at the actin locus. The overall prevalence was 9.3% (71/763). At the 18S rRNA locus, sequences were obtained for 28 of the 71 positives. Sequence analysis identified four species; Cryptosporidium fayeri in seven isolates, Cryptosporidium marcopodum in four isolates, Cryptosporidium xiaoi in six isolates and a novel genotype (kangaroo genotype I) in eleven isolates. Analysis at the actin locus confirmed the genetic distinctness of the novel genotype. The results of the present study indicate that in addition to C. fayeri and C. marcopodum, kangaroos may be capable of being infected with a wider range of Cryptosporidium species and genotypes including livestock species such as C. xiaoi. The novel genotype identified in the kangaroos most likely represents a cryptic species that requires further analyses to confirm its species status. 相似文献
114.
Shafi Sahibzada Stanley Pang Marta Hernndez‐Jover David Jordan Sam Abraham Mark O'Dea Jane Heller 《Zoonoses and public health》2020,67(5):576-586
This observational study aimed to determine MRSA prevalence using strain‐specific real‐time PCR at the pig level, stratified by age groupings, within a pig enterprise. A total of 658 samples were collected from individual pigs (n = 618) and the piggery environment (n = 40), distributed amongst five different pig age groups. Presumptive MRSA isolates were confirmed by the presence of mecA, and MALDI‐TOF was performed for species verification. All isolates were tested against 18 different antimicrobials. MRSA was isolated from 75.2% (95% CI 71.8–78.6) of samples collected from pigs, and 71% of the MRSA isolates from this source were identified as community‐associated (CA)‐MRSA ST93, while the remainder were livestock‐associated (LA)‐MRSA ST398. Amongst environmental isolates, 80% (CI 64.3–95.7) were ST93 and the remainder ST398. All MRSA isolates from pigs and the environment were susceptible to ciprofloxacin, gentamicin, linezolid, mupirocin, rifampicin, sulfamethoxazole–trimethoprim, teicoplanin and vancomycin. Phenotypic rates of resistance were penicillin (100%), clindamycin (97.6%), erythromycin (96.3%), ceftiofur (93.7%), chloramphenicol (81.2%), tetracycline (63.1%) and amoxicillin–clavulanate (63.9%). A low prevalence of resistance (9.2%) was observed against neomycin and quinupristin–dalfopristin. The probability of MRSA carriage in dry sows (42.2%) was found to be significantly lower (p < .001) when compared to other age groups: farrowing sows (76.8%, RR1.82), weaners (97.8%, RR 2.32), growers (94.2%, RR 2.23) and finishers (98.3%, RR 2.33). Amongst different production age groups, a significant difference was also found in antimicrobial resistance for amoxicillin–clavulanate, neomycin, chloramphenicol and tetracycline. Using the RT‐PCR assay adopted in this study, filtering of highly prevalent ST93 and non‐ST93 isolates was performed at high throughput and low cost. In conclusion, this study found that weaner pigs presented a higher risk for CA‐MRSA and antimicrobial resistance compared to other age groups. These findings have major implications for how investigations of MRSA outbreaks should be approached under the One‐Health context. 相似文献
115.
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
116.
Summary Unrelated, unselected 2x haploid-species hybrids that produce 2n eggs, by second division restitution and 2n pollen due to
first division restitution were intercrossed to generate 4x progeny. The 19, 4x families were compared with seven cultivars
for tuber yield, tuber appearance and tuber set. The mean yield of the 4x families was 30% higher than the mean yield of the
cultivars. The best five 4x families outyielded the best five cultivars by 57% and 69% at two locations. Cultivars were superior
for tuber appearance and tuber set. The high yields of the 4x families are due to genetic diversity of the 2x parents and
their ability to transmit that diversity to the 4x progeny utilizing 2n gametes. The potential of the 2x×2x breeding method
is dependent on developing 2x hybrid clones that form 2n eggs and possess desirable tuber types; clones producing 2n pollen
and good tuber quality are available. 相似文献
117.
Summary Trials were carried out in 1984, 1985 and 1986, on a sandy loam soil with an average content of 133 mg/l available potassium
in which the effect of source (KCl, K2SO4) and rate (0, 300, 600, 900 kg K2O/ha) of potassium fertilizer on yield, tuber size, dry matter, reducing sugar, fry test colour and finish fried quality was
examined for two cultivars (Pentland Dell, Maris Piper).
The results indicate a strong influence of cultivar on all measured characters, the rate of potassium fertilizer also gave
significant changes in quality and yield and there were significant year effects. The effect of source of potassium was not
significant. 相似文献
118.
Ronald M Bonett Kenneth H Kozak David R Vieites Alison Bare Jessica A Wooten Stanley E Trauth 《BMC ecology》2007,7(1):7
Background
In most regions of the world human influences on the distribution of flora and fauna predate complete biotic surveys. In some cases this challenges our ability to discriminate native from introduced species. This distinction is particularly critical for isolated populations, because relicts of native species may need to be conserved, whereas introduced species may require immediate eradication. Recently an isolated population of seal salamanders, Desmognathus monticola, was discovered on the Ozark Plateau, ~700 km west of its broad continuous distribution in the Appalachian Mountains of eastern North America. Using Nested Clade Analysis (NCA) we test whether the Ozark isolate results from population fragmentation (a natural relict) or long distance dispersal (a human-mediated introduction). 相似文献119.
Catherine M. Ronning Stanley P. Kowalski Lind L. Sanford John R. Stommel 《Genetic Resources and Crop Evolution》2000,47(4):359-369
The Colorado Potato Beetle is a serious pest of the cultivated potato. Natural resistance has been found in a few wild species, including Solanum chacoense Bitter, in which the resistance is attributed to the presence of leptine glycoalkaloids. Production and accumulation of these compounds within S. chacoense varies widely and appears to be inherited in a quantitative fashion, but high leptine-producing clones occur rarely. In the present study, 15 different accessions from various locations and altitudes of origin within central to northern Argentina and Paraguay were analyzed for foliar glycoalkaloid (leptine, leptinine, solanine, chaconine) content. The objective was to infer the frequency of leptine production in ecogeographically distinct S. chacoense accessions, and to ascertain any possible association between leptine levels/concentrations and ecogeographical location. Leptines were detected in 8 of the 15 accessions, and the amounts within each accession varied widely. Most of the leptine-containing accessions originated from western Argentina except two in province Córdoba in central Argentina. There was no relationship between elevational level and leptine, but there was a negative trend with total glycoalkaloids (TGA) and elevation, due to solanine and chaconine levels which decreased with increasing elevation. In addition, nine unidentified, putative glycoalkaloids were detected, in very high proportions in some individuals and accessions. This study raises interesting questions about glycoalkaloid distribution, helps provide direction for new avenues of leptine and glycoalkaloid research, and proposes a systematic, ecogeographically based method for bioprospecting genes controlling rare plant secondary compounds. 相似文献
120.