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Mario Giorgi

    Mario Giorgi

    A reliable, sensitive and accurate multiple mycotoxin method was developed for the simultaneous determination of 17 mycotoxins in swine, poultry and dairy feeds using stable isotope dilution (13C-ISTD) and (ultra)-high performance liquid... more
    A reliable, sensitive and accurate multiple mycotoxin method was developed for the simultaneous determination of 17 mycotoxins in swine, poultry and dairy feeds using stable isotope dilution (13C-ISTD) and (ultra)-high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). A simple QuEChERS-based method (quick, easy, cheap, effective, rugged and safe) was developed consisting of soaking with a solution of 1% formic acid followed by extraction with acetonitrile, clean-up with C18 sorbent and finally adding 13C-ISTD before the UHPLC-MS/MS analysis. The chromatographic condition was optimized for separation and detection of the 17 mycotoxins using gradient elution. The method’s performance complied with the SANTE/11813/2017 standard and had mean recovery accuracies in the range 70%–120% and precision testing of % relative standard deviation (RSD) ≤ 20%. The limit of detection and limit of quantification values ranged from 0.25 to 40.0 ng/g and 0.5 to 100.0 ng/g, respe...
    Metamizole (MT), an analgesic and antipyretic drug, is rapidly hydrolyzed to the active primary metabolite 4-methylaminoantipyrine (MAA) and relatively active secondary metabolite 4-aminoantipyrine (AA). The aim of this study was to... more
    Metamizole (MT), an analgesic and antipyretic drug, is rapidly hydrolyzed to the active primary metabolite 4-methylaminoantipyrine (MAA) and relatively active secondary metabolite 4-aminoantipyrine (AA). The aim of this study was to assess the pharmacokinetic profiles of MAA and AA after dose of 25 mg/kg MT by intravenous (i.v.), intramuscular (i.m.), oral (p.o.), and rectal (RC) routes in dogs. Six dogs were randomly allocated to an open, single-dose, four-treatment, four-phase, unpaired, crossover study design. Blood was collected at predetermined times within 24 hr, and plasma was analyzed by a validated HPLC-UV method. Plasma concentrations of MAA and AA after i.v., i.m., p.o., and RC administrations of MT were detectable from 5 (i.v. and i.m.) or 30 (p.o. and RC) min to 24 hr in all dogs. The highest concentrations of MAA were found in the i.v., then i.m., p.o., and RC groups. Plasma concentrations of AA were similar for i.v., i.m., and RC, and the concentrations were approxima...
    The mycotoxin patulin (PAT) is well known as a natural contaminant of apple- and other fruit-based products. Pesticides are a group of chemicals abundantly used in agriculture to maximize productivity by protecting crops from pests and... more
    The mycotoxin patulin (PAT) is well known as a natural contaminant of apple- and other fruit-based products. Pesticides are a group of chemicals abundantly used in agriculture to maximize productivity by protecting crops from pests and weeds. Because of their harmful health effects, PAT and pesticides are strictly monitored. The current study was undertaken to investigate the significance of PAT and pyrethroid insecticide contamination in a variety of fruit juices in Bangkok. To do this, a total of 200 fruit juice samples, consisting of 40 samples each of apple, apricot, peach, pineapple, and grape juice, were collected from supermarkets in Bangkok, Thailand. PAT contamination in a variety of fruit juices was detected using validated liquid chromatography-tandem mass spectrometry, and pyrethroid insecticides (cypermethrin, cyfluthrin, and flumethrin) were analyzed using a gas chromatography equipped with micro-electron capture detector. The survey found that PAT concentrations were ...
    To evaluate the pharmacokinetics of two doses of tramadol during isoflurane anaesthesia in sheep and their ability to prevent the cardiovascular response induced by surgical stimulation. Prospective randomized controlled study. A total of... more
    To evaluate the pharmacokinetics of two doses of tramadol during isoflurane anaesthesia in sheep and their ability to prevent the cardiovascular response induced by surgical stimulation. Prospective randomized controlled study. A total of 12 healthy sheep (mean weight, 47.5±7.9 kg) undergoing lumbar transpedicular intervertebral disk nucleotomy. Sheep were sedated with medetomidine, anaesthesia was induced with propofol and maintained with isoflurane at 1.5 vol.%. Baseline heart rate and blood pressure were measured and sheep were randomly assigned an intravenous injection of tramadol (4 or 6 mg kg(-1)). Fentanyl was injected as rescue analgesic if cardiovascular parameters were increased more than 20% compared to baseline. If those variables were below 20% of baseline, the concentration of isoflurane was gradually decreased until parameters returned to the original value. Blood collections were performed at pre-assigned times, and concentrations of tramadol and O-desmethyltramadol (M1) assessed by high-performance liquid chromatography. Time from premedication to anaesthesia induction, anaesthesia time, propofol dose and intraoperative body temperature were similar between doses. Cardiovascular variables remained between ±20% of baseline value, and no statistical difference was observed between treatments. Regardless of the dose of tramadol administered, arterial blood pressure was statistically higher than baseline 10 minutes after tramadol administration, but it gradually returned to previous values. A two-compartment model and a non-compartment model described the pharmacokinetics of tramadol and M1, respectively. Plasma concentrations of tramadol rapidly decreased in the first 2 hours for both doses with an elimination half-life of more than 40 minutes. The M1 maximum concentration was similar for both doses, and it was detected in plasma after 35 minutes. Both doses of tramadol provided adequate cardiovascular stability during spinal surgery in sheep. The pharmacokinetic variables may be used to plan the dosage regime during general anaesthesia.
    The use of antibiotics is necessary to treat bacterial diseases. Determination of optimal dosage in the target animals is increasingly being recognized as vital for maximizing efficacy and minimizing the risk of resistance, so this study... more
    The use of antibiotics is necessary to treat bacterial diseases. Determination of optimal dosage in the target animals is increasingly being recognized as vital for maximizing efficacy and minimizing the risk of resistance, so this study aimed to evaluate the pharmacokinetics/pharmacodynamics (PK/PD) of levofloxacin in broilers. Using a parallel study design, each group of animals (n=20) received 5mg/kg of levofloxacin intravenously (IV) and orally (PO). Plasma, serum and tissues were collected for PK and PD studies. Plasma concentrations of levofloxacin were determined by HPLC. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined against E. coli, isolated in clinical broilers. Ex vivo antibacterial activity was evaluated using the time killing method. Mean values of terminal half-life for IV and PO groups were 6.93 and 8.09h, respectively. Following oral administration, the peak plasma concentration was achieved at 0.88h (Tmax). Mean v...
    Fusarenon X, a member of the type B trichothecene mycotoxin group, has been frequently observed, along with deoxynivalenol (DON) and nivalenol (NIV) as a contaminant in cereals. Our previous study demonstrated that a 14-day FX exposure... more
    Fusarenon X, a member of the type B trichothecene mycotoxin group, has been frequently observed, along with deoxynivalenol (DON) and nivalenol (NIV) as a contaminant in cereals. Our previous study demonstrated that a 14-day FX exposure caused apoptosis in the lymphoid tissues of mice, especially at 0.5 mg/kg bodyweight. However, the relationship between low concentrations of FX and apoptotic molecular machinery remains unclear. In the present study, we investigated the genetic regulatory mechanisms in the thymus and Peyer's patches of mice after 14 days oral administration of FX at 0.5 mg/kg bodyweight. FX caused the up-regulation of Bax, Bid, Trp53, and Caspase-9 mRNA but the relative expression of Fas, TNF, and Caspase-8 remained unchanged. Furthermore, we also determined the toxicity of FX in Jurkat T-cells. FX exhibited a concentration- and time-dependent inhibition of cell viability. Thus, incubation time and FX concentration influence the percentage of apoptotic cells. These data suggested that treatment with low dosage of FX can induce apoptosis in lymphocytes through an effect on Bax, Bid, Trp53, and Caspase-9 and therefore the mitochondrial apoptotic pathway.
    The aim of the present study was to evaluate clinical activity, and the pharmacodynamic and pharmacokinetic profiles, of oral metronomic vinorelbine (VNR) plus dexamethasone (DEX) in metastatic castration-resistant prostate cancer (mCRPC)... more
    The aim of the present study was to evaluate clinical activity, and the pharmacodynamic and pharmacokinetic profiles, of oral metronomic vinorelbine (VNR) plus dexamethasone (DEX) in metastatic castration-resistant prostate cancer (mCRPC) patients. Fourty-one patients (92 % chemotherapy-resistant) received 30 mg/day VNR p.o. thrice a week plus 1 mg/day DEX p.o. until disease progression. Plasma soluble B cell antigen 7 homolog 3 (sB7-H3), vascular endothelial growth factor (VEGF), and thrombospondin-1 (TSP-1), were measured by ELISA. Plasma VNR was detected using a LC-MS-MS system. The fraction of patients free of progression, defined by criteria of the Prostate Cancer Clinical Trials Working Group 2, at 3 months was 61 %. PSA decrease ≥50 % from baseline was observed in 35 % of patients. Median PFS and OS were 4 months (95 % CI, 2.8-6.9) and 17.5 months (95 % CI, 10.8-24.5), respectively. Toxicity was mild, and no grade 4 toxicities were found. The mean plasma VNR Cmax ranged from 1 to 2.7 ng/ml (Tmax 1.1 h) and no evidence of drug accumulation was found. A moderate relationship was found between plasma sB7-H3 and PSA values (r = 0.565; P = 0.0094) at the baseline. Increased PFS (11.3 vs. 2.8 months; P = 0.0298) was observed in patients with sB7-H3 levels <30.25 ng/mL. Plasma VEGF AUC0-24day increased in non-responders (P < 0.0001), whereas responders maintained higher plasma TSP-1 AUC0-24day (P = 0.0063). In conclusion, metronomic VNR plus DEX showed favourable activity, and a low toxicity profile, in mCRPC patients. Plasma sB7-H3, VEGF and TSP-1 levels are potential pharmacodynamic markers at the reached low plasma concentrations of vinorelbine metronomically administered.
    One hundred wheat product samples (50 instant noodle samples and 50 bread samples) were collected from supermarkets in Bangkok, Thailand. Deoxynivalenol (DON) and aflatoxin B1 (AFB1) contamination in these products was analyzed using a... more
    One hundred wheat product samples (50 instant noodle samples and 50 bread samples) were collected from supermarkets in Bangkok, Thailand. Deoxynivalenol (DON) and aflatoxin B1 (AFB1) contamination in these products was analyzed using a validated liquid chromatography-tandem mass spectrometry method. The limit of quantification values of DON and AFB1 in the instant noodles and bread were 2 and 1 ng g(-1), respectively. The survey found that DON was quantifiable in 40% of collected samples, in 2% of noodles (0.089 μg g(-1)), and in 78% of breads (0.004 to 0.331 μg g(-1)). AFB1 was below the limit of quantification of the method in all of the tested samples. The results suggest that the risk of DON exposure via noodles and breads is very low in urban areas of Thailand. No risk can be attributable to AFB1 exposure in the same food matrices, but further studies with a larger sample size are needed to confirm these data.
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    Single intravenous doses of sulpiride 100 mg were administered to 18 patients with renal function impairment, and 6 healthy volunteers. The plasma concentration-time profile is described by a 2-compartment open model. The differences... more
    Single intravenous doses of sulpiride 100 mg were administered to 18 patients with renal function impairment, and 6 healthy volunteers. The plasma concentration-time profile is described by a 2-compartment open model. The differences between the pharmacokinetic parameters of sulpiride for the 2 groups were statistically significant. Elimination half-life, mean residence time and area under the plasma concentration-time curve are significantly greater in renal failure; renal and total clearance, and the cumulative amount of unchanged sulpiride in urine, are significantly reduced but volume of distribution remains unchanged. Creatinine clearance was strongly correlated with renal clearance of sulpiride, elimination rate constant, area under the curve and cumulative amount excreted in urine. For patients with impaired or physiologically reduced renal function receiving long term sulpiride treatment, a 35 to 70% reduction in dose, or extension of the dosage interval by a factor of 1.5 to 3, may be required.
    Combination therapy with two or more analgesics is widely used for conditions associated with moderate to severe pain. Combinations of diverse analgesics with different modes of action can improve the risk-benefit ratio of analgesic... more
    Combination therapy with two or more analgesics is widely used for conditions associated with moderate to severe pain. Combinations of diverse analgesics with different modes of action can improve the risk-benefit ratio of analgesic treatments. The aim of this study is to evaluate the antinociceptive effect of tapentadol (TAP) and flupirtine (FLP), when administered separately or in combination, as well as their synergistic interaction in the orofacial formalin test in rats. After i.p. injection of TAP at different doses (2, 5, 10 and 15mg/kg), the biphasic nociceptive behavior was reduced in a dose-dependent manner in both phase I and II. Conversely, i.p. injection of FLP at different doses (0.6, 1.6, 3.3, 6.6, 16.6 and 22.2mg/kg) induced a dose-dependent antinociceptive effect in phase II only. TAP was found to be more effective than FLP. The interaction between TAP and FLP was synergistic in phase II with an interaction index (γ) of 0.50±0.24. The data reported in this study indi...
    ABSTRACT Enrofloxacin (E) is a commonly used antimicrobial in reptile medicine. However, few studies have been performed in reptile species to determine therapeutic blood levels of the fluoroquinolone (FQ) class of antimicrobial agents.... more
    ABSTRACT Enrofloxacin (E) is a commonly used antimicrobial in reptile medicine. However, few studies have been performed in reptile species to determine therapeutic blood levels of the fluoroquinolone (FQ) class of antimicrobial agents. The aim of the present study was to evaluate the pharmacokinetics of E and its metabolite ciprofloxacin (C) in 21 yellow-bellied slider turtles (Trachemys scripta scripta). The animals were administered 10 mg/kg of E via intracoelomic injection. Blood was collected at scheduled times and analyzed using a validated high-performance liquid chromatography (HPLC) fluorescence method. The turtles showed some indications of transient pain following administration. The pharmacokinetics of E and C were long lasting (196 hours and 168 hours, respectively). This could be of concern where turtles are used for food because of drug tissue residues. The administered dose seemed to be optimal for clinical application because (1) drug concentrations in blood were appropriate for treating bacterial infections without adversely affecting the patient and (2) effective maximum concentration/minimum inhibitory concentration (Cmax/MIC) and area under the simulated blood-time curve (AUC)/MIC ratios were achieved. In conclusion, the dose of 10 mg/kg administered via intracoelomic injection in yellow-bellied slider turtles appeared safe and achieved optimal pharmacodynamic parameters.
    Combination therapy with two or more analgesics is widely used for conditions associated with moderate to severe pain. Combinations of diverse analgesics with different modes of action can improve the risk-benefit ratio of analgesic... more
    Combination therapy with two or more analgesics is widely used for conditions associated with moderate to severe pain. Combinations of diverse analgesics with different modes of action can improve the risk-benefit ratio of analgesic treatments. The aim of this study is to evaluate the antinociceptive effect of tapentadol (TAP) and flupirtine (FLP), when administered separately or in combination, as well as their synergistic interaction in the orofacial formalin test in rats. After i.p. injection of TAP at different doses (2, 5, 10 and 15mg/kg), the biphasic nociceptive behavior was reduced in a dose-dependent manner in both phase I and II. Conversely, i.p. injection of FLP at different doses (0.6, 1.6, 3.3, 6.6, 16.6 and 22.2mg/kg) induced a dose-dependent antinociceptive effect in phase II only. TAP was found to be more effective than FLP. The interaction between TAP and FLP was synergistic in phase II with an interaction index (γ) of 0.50±0.24. The data reported in this study indi...
    Obesity is a worldwide pathological condition that strongly impairs human health, and, to date, no effective therapy against excessive fat accumulation has been found yet. Since overweight correlates with an increased oxidative stress,... more
    Obesity is a worldwide pathological condition that strongly impairs human health, and, to date, no effective therapy against excessive fat accumulation has been found yet. Since overweight correlates with an increased oxidative stress, our aim is to investigate the antioxidant effects of cerium oxide nanoparticles (nanoceria) as a potential pharmaceutical approach for the treatment of obesity. Nanoceria were tested both in vitro and in vivo; they were proven to interfere with the adipogenic pathway by reducing the mRNA transcription of genes involved in adipogenesis, and by hindering the triglycerides accumulation in 3T3-L1 pre-adipocytes. Nanoceria, intraperitonally injected in Wistar rats, did not have appreciable toxic effects, but instead efficiently contributed in reducing the weight gain and in lowering the plasma levels of insulin, leptin, glucose and triglycerides.
    A rapid and sensitive HPLC method has been developed for the quantification of mirtazapine (MRZ), a noradrenergic and specific serotonergic inhibitor antidepressant (NaSSA) and its two major metabolites N-desmethyl mirtazapine (NDM) and... more
    A rapid and sensitive HPLC method has been developed for the quantification of mirtazapine (MRZ), a noradrenergic and specific serotonergic inhibitor antidepressant (NaSSA) and its two major metabolites N-desmethyl mirtazapine (NDM) and 8-hydroxymirtazapine (8-OHM) in human plasma. The separation was achieved using Chromolith C18 column and a mobile phase of acetonitrile: phosphate buffer (pH = 3, 20:80, v/v) in isocratic mode at a flow rate of 2 mL/min. A fluorescence detector was set at 290 and 350 nm for excitation and emission, respectively. Zolpidem was used as the internal standard. Liquid-liquid extraction was applied for sample clean up. All analytes were eluted in less than 5 minutes with LOQ of 1 ng/mL for MRZ and 2 ng/mL for both NDM and 8-OHM. The developed method was successfully applied to quantify MRZ and its metabolites in plasma of a healthy volunteer.
    The effect of beta-naphthoflavone (beta-NF) on several catalytic activities of cytochrome P450 (CYP) and phase II enzymes putatively controlled by [Ah]-receptor activation in the liver, heart and kidney of gilthead seabream, was... more
    The effect of beta-naphthoflavone (beta-NF) on several catalytic activities of cytochrome P450 (CYP) and phase II enzymes putatively controlled by [Ah]-receptor activation in the liver, heart and kidney of gilthead seabream, was investigated. In the liver, beta-NF treatment [intraperitoneal injection (i.p.) 50 mg/kg] resulted in an increase of CYP content, immunoreactive CYP 1A and methoxyresorufin-O-demethylase (MEROD), pentoxyresorufin O-depentylase (PROD) and ethoxyresorufin-O-deethylase (EROD) activities. However, beta-NF had no effect on any of the hepatic phase II enzymes examined (benzaldehyde dehydrogenase, propionaldehyde dehydrogenase, glutathione S-transferase, UDP-glucuronyl-transferase, DT-diaphorase). Single i.p. injection of 10 mg/kg beta-NF showed a maximal induction of CYP 1A-like protein and EROD activity after 3-7 days. CYP 1A and EROD returned to control levels 18-days post-treatment. beta-NF injection also caused a rapid increase of a single band size of mRNA re...

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