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31.
The effects of UV radiation on the chemical and sensory characteristics of virgin olive oils (cv. Arbequina and Picual) were assessed. Even small doses of UV radiation induced oxidation of the virgin olive oil samples. Total phenols and fatty acids contents decreased during the process as well as the intensity of the bitter and fruity sensory attributes, while the intensity of the rancid sensory attribute notably increased. Acetaldehyde, 2-butenal, 2-pentenal, octane, octanal, hexanal, nonanal, and 2-decenal were the volatile compounds most affected, showing an important increase during the irradiation process. Nonanal, hexanal, and pentanal showed high correlation with the rancid sensory attribute (90%, 86%, and 86%, respectively). 2-Decenal and nonanal concentrations allowed us to predict the alteration level of the samples by mean of multiple Ridge regression. 相似文献
32.
Steagall PV Carnicelli P Taylor PM Luna SP Dixon M Ferreira TH 《Journal of veterinary pharmacology and therapeutics》2006,29(6):531-537
This study compared pressure and thermal thresholds after administration of three opioids in eight cats. Pressure stimulation was performed via a bracelet taped around the forearm. Three ball-bearings were advanced against the forearm by inflation of a modified blood pressure bladder. Pressure in the cuff was recorded at the end point (leg shake and head turn). Thermal threshold was tested as previously reported using a heated probe held against the thorax [Dixon et al. (2002) Research in Veterinary Science, 72, 205]. After baseline recordings, each cat received subcutaneous methadone 0.2 mg/kg, morphine 0.2 mg/kg, buprenorphine 0.02 mg/kg or saline 0.3 mL in a four period cross-over study. Measurements were made at 15, 30, 45 min and 1, 2, 3, 4, 8, 12 and 24 h after the injection. Data were analysed by anova (P<0.05). There were no significant changes in thresholds after saline. Thermal threshold increased at 45 min after buprenorphine (maximum 2.8+/-3 degrees C), 1-3 h after methadone (maximum 3.4+/-1.9 degrees C) and 45 min to 1 h (maximum 3.4+/-2 degrees C) after morphine. Pressure threshold increased 30-45 min (maximum 238+/-206 mmHg) after buprenorphine, 45-60 min after methadone (maximum 255+/-232 mmHg) and 45-60 min and 3-6 h (maximum 255+/-232 mmHg) after morphine. Morphine provided the best analgesia, and methadone appears a promising alternative. Buprenorphines limited effect was probably related to the subcutaneous route of administration. Previously, buprenorphine has produced much greater effects when given by other routes. 相似文献
33.
da Silva RG Reyes FG Sartori JR Rath S 《Journal of veterinary pharmacology and therapeutics》2006,29(5):365-372
The pharmacokinetics of enrofloxacin (ENRO), a fluoroquinolone antimicrobial agent, was studied in male broiler chickens (Cobb) after single oral administration of 10 mg of ENRO/kg b.w. A high-performance liquid chromatography-photodiode array detector (DAD) (HPLC-DAD) method was developed and validated and used for quantitation of ENRO and its major metabolite ciprofloxacin in plasma. The HPLC analyses were carried out using a cationic-octadecyl mixed column and 0.05 mol/L phosphate buffer (pH 2.5)/acetonitrile as mobile phase. The sample preparation of plasma consisted of the precipitation of proteins followed by solid phase extraction on cationic-octadecyl mixed cartridges. The method was validated considering linear range, linearity, selectivity, sensitivity, limit of detection (LOD), limit of quantitation (LOQ), intra- and inter-day precisions and accuracy. The LOD and LOQ for both fluoroquinolones were 60 and 200 ng/mL for plasma. The plasma concentration vs. time graph was characteristic of a two-compartment open model. The maximal plasma concentration of 1.5 +/- 0.2 mg/mL was achieved at 9 +/- 2 h. The elimination half-life and the mean residence time of ENRO were 1.5 +/- 0.2 and 15.64 h, respectively. The area under the concentration-time curve was calculated as 35 +/- 4 mgxh/mL. 相似文献
34.
M. G. Luna N. E. Sánchez P. C. Pereyra E. Nieves V. Savino E. Luft E. Virla S. Speranza 《EPPO Bulletin》2012,42(2):260-267
By means of an international project, Argentinian and Italian researchers are carrying out joint research to study biological and ecological aspects of Tuta absoluta biological control. This paper lists indigenous natural enemies reported for T. absoluta, as well as the current results on T. absoluta egg and larval parasitoids in both countries. Parasitoid species that conformed to different guilds are shown to coexist in cropping conditions, and some show positive characteristics as potential biocontrol agents against T. absoluta by means of augmentative releases. Future laboratory and field evaluations of the efficacy of biological control programmes in Argentina and Italy are proposed. 相似文献
35.
36.
Paschoal JA Bicudo ÁJ Cyrino JE Reyes FG Rath S 《Journal of veterinary pharmacology and therapeutics》2012,35(1):90-96
Defining pharmacokinetic parameters and depletion intervals for antimicrobials used in fish represents important guidelines for future regulation by Brazilian agencies of the use of these substances in fish farming. This article presents a depletion study for oxytetracycline (OTC) in tilapias (Orechromis niloticus) farmed under tropical conditions during the winter season. High performance liquid chromatography, with fluorescence detection for the quantitation of OTC in tilapia fillets and medicated feed, was developed and validated. The depletion study with fish was carried out under monitored environmental conditions. OTC was administered in the feed for five consecutive days at daily dosages of 80 mg/kg body weight. Groups of ten fish were slaughtered at 1, 2, 3, 4, 5, 8, 10, 15, 20, and 25 days after medication. After the 8th day posttreatment, OTC concentrations in the tilapia fillets were below the limit of quantitation (13 ng/g) of the method. Linear regression of the mathematical model of data analysis presented a coefficient of 0.9962. The elimination half-life for OTC in tilapia fillet and the withdrawal period were 1.65 and 6 days, respectively, considering a percentile of 99% with 95% of confidence and a maximum residue limit of 100 ng/g. Even though the study was carried out in the winter under practical conditions where water temperature varied, the results obtained are similar to others from studies conducted under controlled temperature. 相似文献
37.
Oliet Juan A. Artero Francisco Cuadros Simón Puértolas Jaime Luna Lourdes Grau Jose M. 《New Forests》2012,43(5-6):925-939
New Forests - Increasing plant size has been considered a way to improve survival and growth of planted containerized stock under dry conditions. Additionally, deep planting provides advantages to... 相似文献
38.
Mannarino R Luna SP Monteiro ER Beier SL Castro VB 《Veterinary anaesthesia and analgesia》2012,39(2):160-173
ObjectiveTo evaluate the effects of a constant rate infusion (CRI) of lidocaine alone or in combination with ketamine on the minimum infusion rate (MIR) of propofol in dogs and to compare the hemodynamic effects produced by propofol, propofol-lidocaine or propofol-lidocaine-ketamine anesthesia.Study designProspective, randomized cross-over experimental design.AnimalsFourteen adult mixed-breed dogs weighing 15.8 ± 3.5 kg.MethodsEight dogs were anesthetized on different occasions to determine the MIR of propofol alone and propofol in combination with lidocaine (loading dose [LD] 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) or lidocaine (LD 1.5 mg kg?1, CRI 0.25 mg kg?1 minute?1) and ketamine (LD 1 mg kg?1, CRI 0.1 mg kg?1 minute?1). In six other dogs, the hemodynamic effects and bispectral index (BIS) were investigated. Each animal received each treatment (propofol, propofol-lidocaine or propofol-lidocaine-ketamine) on the basis of the MIR of propofol determined in the first set of experiments.ResultsMean ± SD MIR of propofol was 0.51 ± 0.08 mg kg?1 minute?1. Lidocaine-ketamine significantly decreased the MIR of propofol to 0.31 ± 0.07 mg kg?1 minute?1 (37 ± 18% reduction), although lidocaine alone did not (0.42 ± 0.08 mg kg?1 minute?1, 18 ± 7% reduction). Hemodynamic effects were similar in all treatments. Compared with the conscious state, in all treatments, heart rate, cardiac index, mean arterial blood pressure, stroke index and oxygen delivery index decreased significantly, whereas systemic vascular resistance index increased. Stroke index was lower in dogs treated with propofol-lidocaine-ketamine at 30 minutes compared with propofol alone. The BIS was lower during anesthesia with propofol-lidocaine-ketamine compared to propofol alone.Conclusions and clinical relevanceLidocaine-ketamine, but not lidocaine alone, reduced the MIR of propofol in dogs. Neither lidocaine nor lidocaine in combination with ketamine attenuated cardiovascular depression produced by a continuous rate infusion of propofol. 相似文献
39.
Paulo VM Steagall Ludovic Pelligand Tatiana Giordano Christophe Auberger John W Sear Stelio PL Luna Polly M Taylor 《Veterinary anaesthesia and analgesia》2013,40(1):83-95
ObjectiveTo describe simultaneous pharmacokinetics (PK) and thermal antinociception after intravenous (IV), intramuscular (IM) and subcutaneous (SC) buprenorphine in cats.Study designRandomized, prospective, blinded, three period crossover experiment.AnimalsSix healthy adult cats weighing 4.1 ± 0.5 kg.MethodsBuprenorphine (0.02 mg kg?1) was administered IV, IM or SC. Thermal threshold (TT) testing and blood collection were conducted simultaneously at baseline and at predetermined time points up to 24 hours after administration. Buprenorphine plasma concentrations were determined by liquid chromatography tandem mass spectrometry. TT was analyzed using anova (p < 0.05). A pharmacokinetic-pharmacodynamic (PK-PD) model of the IV data was described using a model combining biophase equilibration and receptor association-dissociation kinetics.ResultsTT increased above baseline from 15 to 480 minutes and at 30 and 60 minutes after IV and IM administration, respectively (p < 0.05). Maximum increase in TT (mean ± SD) was 9.3 ± 4.9 °C at 60 minutes (IV), 4.6 ± 2.8 °C at 45 minutes (IM) and 1.9 ± 1.9 °C at 60 minutes (SC). TT was significantly higher at 15, 60, 120 and 180 minutes, and at 15, 30, 45, 60 and 120 minutes after IV administration compared to IM and SC, respectively. IV and IM buprenorphine concentration-time data decreased curvilinearly. SC PK could not be modeled due to erratic absorption and disposition. IV buprenorphine disposition was similar to published data. The PK-PD model showed an onset delay mainly attributable to slow biophase equilibration (t1/2ke0 = 47.4 minutes) and receptor binding (kon = 0.011 mL ng?1 minute?1). Persistence of thermal antinociception was due to slow receptor dissociation (t1/2koff = 18.2 minutes).Conclusions and clinical relevanceIV and IM data followed classical disposition and elimination in most cats. Plasma concentrations after IV administration were associated with antinociceptive effect in a PK-PD model including negative hysteresis. At the doses administered, the IV route should be preferred over the IM and SC routes when buprenorphine is administered to cats. 相似文献
40.