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A preliminary study on the occurance of Pyrrolizidine Alkaloids in Italian honey
No full textIn the last decade, the health safety of honey has been taken into consideration as it can be contaminated by drugs used to protect bees against a variety of brood disease and or by natural toxins like pyrrolizidine alkaloids (PAs). Samples of polyflora honey were obtained from local beekeepers (70) of the Veneto region or from the market, and lycopsamine,heliotrine, echimidine, senecionine, seneciphylline and retrorsine were measured using a liquid chromatography coupled with a mass spectrometry method to evaluete the contamination of Veneto honey
Glucocorticoid residues in bovine liver
No full textDEXAMETHASONE (dex), betamethasone (BETA) and prednisolone (PREDN) are synthetic corticosteroids
authorized in cattle breeding for the treatment of metabolic disorders and inflammatory diseases.
In recent years, a widespread use of corticosteroids, as growth promoters, at lower doses than therapeutic
ones, has been observed, despite the use of corticosteroids at different indications than those authorized
and for purposes other than therapeutic is banned by the EU to safeguard the health of the consumer
(Directive 2003/74/EC). During 2007 a surveillance plan was conducted in several slaughterhouses of the
Regione del Veneto and about 300 cattle were monitored; specimen of different tissues and organs were
collected from 72 animals to detect, through chemical, biomolecular and histological examination, the
presence of previous illicit treatments.
Based on the results of the histological analyses on thymus samples, animals were classified into 23
Suspected/Doubts and 16 Negative. Liver samples from these 39 animals were analyzed for the presence of
residues of steroids, and urines were analyzed for residues of natural cortisol and cortisone plus synthetic
corticosteroids (1). To highlight the presence of corticosteroid residues, a multiresidue method in liquid
chromatography coupled with mass spectrometry (LC‐MS) has been used to identify and quantify the
presence of DEX, BETA and PREDN; the method has been validated for both matrix liver and urine.
The data of confirmatory method adopted, indicated the DEX presence in 11 samples of bovine liver, 10
from the group of 23 animals classified as suspects by histological examination, while only 1 sample out of
16 was not negative; in 6 positive samples, DEX concentrations were higher than the allowed MRL (2
ug/kg).
The analytical data confirm the high risk for the consumer of foodstuffs of animal origin from cattle illegally
treated with glucocorticoids. Based on the results obtained, it can be stated that the histological examination helps to doscriminate animals treted with corticosteroids (2).
1) Capolongo F. et al (2007) Anal. Chim. Acta 586, 228‐232.
2) Cannizzo F. T. et al. (2011) Anal. Chim. Acta 700, 95‐104
A multivariate statistical approach to identify the factors influencing the grayanotoxin content of Italian Rhododendron honey
No full textThis work represents a step in the identification of hazards associated with the consumption of Italian Rhododendron honey, which could contain grayanotoxins, which can be found in plant belonging to genera of the Ericaceae family. An LC-MS/MS method was developed and validated to quantify Grayanotoxin I (GTX I) in 125 Italian Rhododendron honeys collected from 2017 to 2019. Sensitivity and linearity were demonstrated in the range 10–1000 μg kg−1, and a LOQ value of 10 μg kg−1 was obtained. Absolute recovery ranged from 88.2% to 99.3% and no matrix effect was measured. GTX I was found in the 30.4% of the samples, and the concentrations ranged from 12.3 to 103.5 μg kg−1. Multivariate statistical approaches were applied to investigate the relationship between the presence/absence of GTX I and different honey features (e.g. environmental factors, quality aspects). The main factors affecting the presence of GTX I resulted the environment, province, altitude and the purity of botanical origin. The mean GTX I level detected in the ‘positive’ Italian Rhododendron honeys was 119–668 times lower than GTX content found in mad honeys, which caused human intoxication, so the probability of an acute toxic syndrome, in this scenario, is remote
Pyrrolizidine alkaloids and relative N-oxides evaluation in Italian honey from the Veneto region (Italy) by LC-MS/MS.
No full textPyrrolizidine alkaloids (PAs) are the most common class of natural toxins (approximately 350 types), synthesised by a wide variety plant species and the presence of PAs in food and feed clearly represents a potential risk to human and animals. In this study, an analytical method by liquid chromatography coupled to mass spectrometry (LC-MS/MS) was applied to evaluate and characterise PA and their N-oxides (PANOs) content in Italian honey. Echimidine, heliotrine, lycopsamine, senecionine, seneciphylline, retrorsine and the corresponding PANOs were considered.
For the matrix clean-up and the extraction of PAs/PANOs, the solid phase extraction with non-polar/cation-exchange polymeric cartridges, PLEXA 200 mg/6 mL, (Agilent Technologies, USA) were adopted. Analyses were performed by a LTQ XL ion trap, equipped with a heated electrospray ionisation probe, operating in positive ion mode (Thermo Fischer Scientific, San Jose, CA, USA). The linearity of the calibration curves was evaluated in the range of 0.25-50 ug kg-1, the mean recovery ranged from 82.70 % to 104.16 %; LOQ was 0.25 ug kg-1 for all PAs/PANOS, fully satisfying the limit stated in the document “Summary report of the standing committee on plants, animals, food and feed held in Brussels on 1 July 2014”.
147 honey samples from Veneto region were analysed, according to their geographical origin. Analyses showed that 69% of the honey samples were negative for all PAs/PANOs monitored, 31% were positive. In all positive samples the contribute from target PANOs was negligible (range 0.39-1.52 μg kg-1). The total content of PAs/PANOs monitored in Veneto honey ranged from 0.25 to 64.44 μg kg-1. These results are not consistent with previous studies about honey samples from other European countries. Taking into account the indication from CONTAM Panel (EFSA 2011), based on the Margin of Exposure (MOE) approach, a honey sample must not exceed a PAs/PANOs total content of 21 μg kg-1; only 9% of our samples exceed this limit. Moreover, preliminary results showed an influence of two important factor as season (summer > spring) and territory (hills > lowland) on the total content of PAs/PANOs in honey.
Honey produced from local beekeepers of Veneto region is not a real threat to health, while a monitoring program of PAs/PANOs in honey is highly desirable to risk assessment
Simulation of a field condition to evaluate the risk of enrofloxacin-resistant Pasteurella multocida strain selection in food producing rabbits treated via drinking water
Get PDFIntroduction: Pasteurella multocida is a key bacterial agent involved in most
respiratory disorders in rabbits. The objective of this study was to evaluate the risk
of selecting Pasteurella multocida strains resistant to enrofloxacin (ENRO) in food
producing rabbits treated with ENRO via drinking water, according to the standard
husbandry practices. Indeed, despite the EU community guidelines recommend
a prudent use of antibiotics and promote new strategies to prevent bacterial
diseases, antimicrobial therapy remains the primary approach for pasteurellosis
management in rabbits. Therefore, the potential risk of selecting resistant bacteria
in food-producing animals requires identifying optimized dosage regimens to
minimize resistance emergence and to extend the useful lifetime of the drug.
Methods: In this study, we isolated Pasteurella multocida strains from bacterial
colonies sampled in nasal swabs collected from 6 healthy rabbits and 12 rabbits
suffering respiratory disorders. Animals were sourced from industrial farms and
were randomly selected to investigate the inter-individual variability in antimicrobial
exposure associated with treatment via drinking water. Sick rabbits underwent an
approved ENRO treatment (10 mg/kg for 5 days) administered via drinking water,
following standard husbandry practices. We investigated the minimum inhibitory
concentration (MIC), the minimum bactericidal concentration (MBC), and the
mutant prevention concentration (MPC) of ENRO against bacterial strains in
healthy rabbits and in sick rabbits before and after treatment. We recorded plasma
drug concentrations of treated animals, and we applied the mutant selection
window (MSW) approach to each subject. Finally, we calculated the PK/PD indices
for concentration-dependent antimicrobials to assess ENRO’s clinical efficacy
and it’s potential for promoting resistance using published pharmacokinetic (PK)
parameters and maximum drug plasma concentrations recorded in this study.
Results: Here we showed that treatment with ENRO improved clinical signs
in rabbits with pasteurellosis but failed to completely eradicate the pathogen,
consistent with previous studies. MPC-based analysis showed acquired
resistance and potential ENRO-induced shift to a lesser sensitivity in the P.
multocida population. Moreover, MSW analysis revealed that 45% of treated
rabbits exhibited potential for drug resistance selection.
Conclusion: These findings suggest that the current ENRO dosing regimen for
pasteurellosis in rabbits is inadequate and may contribute to resistance development
Evaluation of Some Pyrrolizidine Alkaloids in Honey Samples from the Veneto Region (Italy) by LC-MS/MS
No full textAbstract Pyrrolizidine alkaloids (PAs) are natural toxins, supposed to be converted to hepatotoxic metabolites in the liver of mammalians, and preventing the uptake of PAs is the only way to reduce the attendant health risks. A liquid chromatography coupled to mass spectrometry (LC-MS/MS) method was developed according to the Decision 2002/657/ EC, to evaluate the contamination of Veneto honey by the following pyrrolizidine alkaloids: echimidine, heliotrine, lycopsamine, retrorsine, senecionine, and seneciphylline, as well as their N-oxides (pyrrolizidine alkaloid N-oxides
(PANOs)). Before the solid-phase extraction, a reduction step with zinc dust in the presence of sulfuric acid was carried out for the reduction of PANOs to PAs in honey samples. For all of the analytes, the mean recovery ranged between 82.70 and 104.16 % and the limit of quantification (LOQ) was 0.25 μg kg−1, fully satisfying the LOQ of 1 μg kg−1 as requested by EFSA (2012). The validated method was applied for the analysis of 60 Veneto samples produced from local beekeepers. Among the samples, 17 % were positive for the PAs monitored, and their total PA contents ranged from 0.6 to 17.6 μg kg−1. In all of the samples, the contribution from the PANOs appeared to be negligible. The total PA contents found in the Veneto honey samples never exceeded the limit of 0.42 μg per day for an individual weighing 60 kg, established by the German Federal Institute of Risk Assessment (BfR) in 2011. These preliminary results provide useful advice to beekeepers for finding the most suitable location for beehives to achieve a substantial reduction of the PAs in honey
IN VITRO AND IN VIVO COMPARISON OF ENROFLOXACIN METABOLISM IN TURKEY.
No full textEnrofloxacin (E) is a synthetic fluoroquinolone antimicrobial agent, administered orally to turkeys for the
treatment of respiratory and intestinal diseases. The aim of the study is to assess, in turkey, the extent of
the in vitro hepatic biotransformation of Enrofloxacin (E) into Ciprofloxacin (C), its active metabolite, as the
sum of E+C is the marker residue for edible tissues from treated turkey fixed by EU to minimize the risk for
human health
Monitoring of illicit corticosteroid use in beef cattle by using a histological-analytical approach.
No full textIl desametasone (DEX), il besametasone (BETA) ed il prednisolone (PREDN), sono corticosteroidi di sintesi, autorizzati nell’allevamento
bovino come analgesici-antiinfiammatorii e per il trattamento di patologie metaboliche. La loro somministrazione
ai bovini a dosaggi sub-terapeutici per tempi prolungati, rappresenta una pratica illecita con effetti anabolizzanti, vietata
dall’Unione Europea, a tutela della salute pubblica, con la Direttiva 97/2008/EC1.
Nell’ambito di un piano di sorveglianza condotto nel 2007, in collaborazione con i Servizi Veterinari della Regione Veneto, sono
stati monitorati al macello 300 bovini. Al momento della macellazione, da 72 animali, sono stati prelevati timo, fegato e urine,
per valutare mediante un approccio combinato istologico-analitico, trattamenti non dichiarati con cortisonici. Dopo l’esame
istologico del timo, 23 campioni di fegato e di urina di animali sospetti sono stati analizzati in cromatografia liquida accoppiata
alla spettrometria di massa (LC-MS/MS), per evidenziare la presenza di residui di DEX, BETA e PREDN, insieme a
16 campioni provenienti da animali classificati come negativi.
In 10 campioni di fegato “sospetti” e in un solo campione negativo, erano presenti residui di DEX. In 4 campioni di urina, corrispondenti
a campioni epatici in cui il DEX era superiore a 2 ng/g, erano presenti residui di DEX. L’esame istologico ha permesso
perciò di discriminare in modo sufficiente gli animali trattati illecitamente con cortisonici da quelli non trattati, seppure
con un falso negativo. Confrontando i risultati di fegato ed urine, con i dati di eliminazione urinaria del DEX presenti in letteratura,
è stato possibile confermare che i trattamenti non autorizzati, erano avvenuti anche in prossimità della macellazione, fenomeno
che può comportare un reale rischio per il consumatore di alimenti provenienti da animali trattati con cortisonici
Development and optimisation of a fentanyl pharmacokinetic model for target-controlled infusion (TCI) in anaesthetised dogs
No full textObjective
To investigate pharmacokinetics (PK) of fentanyl administered by target-controlled infusion (TCI), and to develop a PK model optimized by covariates for TCI in anaesthetized dogs.
Study design
Prospective clinical study.
Animals
A group of 20 client-owned dogs with spinal pain undergoing anaesthesia for magnetic resonance imaging.
Methods
Fentanyl was administered as an infusion to 20 anaesthetized dogs using a TCI system incorporating a previously described fentanyl two-compartment PK. Arterial blood samples were collected at specific time points during the infusion and over 60 minutes post-infusion for measurement of fentanyl plasma concentrations. The predictive performance of the Sano PK model was assessed by comparing predicted and measured plasma concentrations. A population PK analysis was then performed using a nonlinear mixed-effect modelling approach, allowing inter- and intra-individual variability estimation. Finally, a quantitative stepwise evaluation of the influence of various covariates such as weight, body condition score, size, size-related age, sex and type of premedication on the PK model was considered.
Results
Overall predictive performance of the Sano PK set of variables was not clinically acceptable in anaesthetized dogs. Fentanyl PK was best described by a three-compartment model. Weight and sex were found to affect the volume of distribution of the central compartment. Addition of these two covariate/variable associations resulted in a reduction of the objective function value from -340.18 to -448.34, and of the median population weighted residual and the median population absolute weighted residual from 16.1% and 38.6% to 3.9% and 20.3%, respectively. Fentanyl infusions at measured concentrations up to 5.4 ng mL-1 in sevoflurane anaesthetized dogs resulted in stable anaesthesia and smooth recoveries without complications.
Conclusions and clinical relevance
A population three-compartment PK model for fentanyl TCI in anaesthetized dogs was developed. Weight and sex have been detected and incorporated as significant covariates
Development and validation of an LC-MS/MS method for the quantification of fluoroquinolones in several matrices from treated turkeys
No full textThe study presents a sensitive and reliable confirmatory method for the extraction, identification, quantification of five fluoroquinolones (FQ) namely enrofloxacin, ciprofloxacin, difloxacin, sarafloxacin
and flumequine, in plasma, liver, kidney, muscle, skin þ fat, lung and intestinal content from turkeys. For the extraction and matrix clean-up of FQ residues from all biological matrices, the Quick Easy Cheap Effective Rugged Safe (QuEChERS) methodology was adopted; only for plasma samples acetonitrile was used. The analyses were performed by liquid chromatography with mass spectrometry detection (LCeMS).
LC separation was performed on a C18 Kinetex column (100 2.1 mm, 2.6 mm, Phenomenex, CA, USA) with gradient elution using ammonium acetate solution (10 mM, pH 2.5) and methanol containing 0.1% formic acid. Mass spectrometric identification was done using an LTQ XL ion trap (Thermo Fisher Scientific, CA, USA), with a heated electrospray ionization probe, in positive ion mode.
The method was validated according to the European Legislation (decision 2002/657/EC) and EMA guideline (EMA/CVMP/VICH/463202/2009); selectivity, linearity response, trueness (in terms of recovery),
precision (within-day repeatability and within-laboratory reproducibility), limit of detection, limit of quantification, decision limits, detection capability, absolute recovery and robustness were evaluated
using turkey blank matrices. All data were within the required limits established for confirmatory methods except for flumequine which presented a recovery value slightly higher than 110% in muscle
and intestinal content. For all FQs, all the extraction rates were greater than 70% and limits of quantification ranged from 1.2 mg/ kg to 118.8 mg/ kg. This fast and robust method was suitable for the identification and quantification of FQ residues in tissues, plasma and intestinal content as confirmed by data obtained from incurred samples of turkeys treated at farm for therapeutic purposes
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