17 results on '"Pacifici R."'
Search Results
2. Issues in Methodology and Applications for Therapeutic Drug Monitoring of Fluoxetine and Norfluoxetine Enantiomers
- Author
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Zuccaro, P., primary, Pacifici, R., additional, Altieri, I., additional, Avenoso, A., additional, Pellegrini, M., additional, Spina, E., additional, Perucca, E., additional, and Pichini, S., additional
- Published
- 1998
- Full Text
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3. 46 ENANTIOSELECTIVE LIQUID CHROMATOGRAPHIC DETERMINATION OF THE S(+) AND R(-) ENANTIOMERS Of OXCARBAZEPINE ME TABOLITES
- Author
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Pacifici, R, primary, Altieri, I, additional, Passa, A R, additional, and Pichini, S, additional
- Published
- 1995
- Full Text
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4. Δ9-Tetrahydrocannabinol and Cannabidiol Time Courses in the Sera of "Light Cannabis" Smokers: Discriminating Light Cannabis Use from Illegal and Medical Cannabis Use.
- Author
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Pichini S, Mannocchi G, Berretta P, Zaami S, Pirani F, Pacifici R, and Busardò FP
- Subjects
- Adult, Cannabidiol blood, Chromatography, High Pressure Liquid methods, Dronabinol blood, Female, Humans, Male, Middle Aged, Tandem Mass Spectrometry methods, Young Adult, Cannabidiol pharmacokinetics, Cannabis chemistry, Dronabinol pharmacokinetics, Marijuana Smoking, Medical Marijuana, Substance Abuse Detection methods
- Abstract
Background: Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) time courses in serum and physiological and behavioral effects associated with smoking 1 or 4 "light cannabis" cigarettes were studied. Biomarkers to differentiate light cannabis versus illegal and medical cannabis use were also investigated., Methods: Sera were obtained at different times from 6 healthy light cannabis consumers and 6 individuals who smoked 1 and 4 cigarettes, within 4 hours through a liquid-liquid method and analyzed by liquid chromatography-tandem mass spectrometry., Results: In serum, minimal THC concentration was observed after a single cigarette smoke, while repeated smoking increased it by 1 order of magnitude. CBD concentrations were higher, but did not increase linearly, probably because it does not preferentially volatilize compared with THC. The highest THC and CBD concentrations were observed 0.5 hours after the start of the smoking of 1 cigarette. Serum THC ranged from 2.7 to 5.9 ng/mL, while serum CBD varied from 5.7 to 48.2 ng/mL. Similarly, the highest THC and CBD concentrations were observed 0.5 hours after the smoking of 4 cigarettes. Specifically, the ranges were THC: 11.0-21.8 ng/mL and CBD: 19.4-35.3 ng/mL. In both cases, the mean THC/CBD concentration ratio ranged from 0.2 to 0.9. There were no significant changes in blood pressure, heart rate, and body temperature, but participants who smoked 4 cigarettes experienced severe drowsiness., Conclusions: THC and CBD time courses in the sera of light cannabis smokers were similar to those previously observed in oral fluid and blood. Serum THC/CBD concentration ratio not higher than the mean value of 0.9 might be a useful biomarker to identify use of light cannabis versus that of illegal THC cannabis (where THC/CBD concentration ratios are generally greater than 10) or versus that of medical cannabis (where ratios are greater than 1). Consumers should be advised of possible drowsiness after he repeated smoking of light cannabis cigarettes.
- Published
- 2020
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5. Acute Intoxications and Fatalities From Illicit Fentanyl and Analogues: An Update.
- Author
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Pichini S, Solimini R, Berretta P, Pacifici R, and Busardò FP
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- Analgesics, Opioid adverse effects, Drug Contamination, Fentanyl analogs & derivatives, Humans, Tissue Distribution, Cause of Death, Fentanyl adverse effects, Fentanyl pharmacokinetics, Illicit Drugs adverse effects, Illicit Drugs pharmacokinetics
- Abstract
Illicit fentanyl and its analogues are very dangerous synthetic opioids, with high abuse potential and severe adverse effects including coma and death. They are used as adulterants in street heroin, cocaine, and methamphetamine, or as heroin substitutes sold to unaware users with a high risk of overdoses. Fentanyl and its analogues have also been identified in counterfeit medicinal products, such as oxycodone, hydrocodone, and alprazolam tablets, or as components of speedball mixtures together with cocaine or other stimulants. In recent years, a number of epidemics involving acute intoxications and deaths related to illicit fentanyl or its analogues have occurred in the United States, Europe, Canada, Australia, and Japan. In several cases, fatalities involved polysubstance use. A review of the most recent case reports or case series of acute intoxications and fatalities involving illicit fentanyl and its newest analogues is herein provided, together with the available information on intoxication symptoms, eventual death cause, and metabolites detected in different biological fluids and reported concentrations.
- Published
- 2018
- Full Text
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6. Testing ethylglucuronide in maternal hair and nails for the assessment of fetal exposure to alcohol: comparison with meconium testing.
- Author
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Morini L, Marchei E, Tarani L, Trivelli M, Rapisardi G, Elicio MR, Ramis J, Garcia-Algar O, Memo L, Pacifici R, Groppi A, Danesino P, and Pichini S
- Subjects
- Alcohol Drinking adverse effects, Biomarkers analysis, Chromatography, Liquid methods, Esters analysis, Ethanol adverse effects, Fatty Acids analysis, Female, Fetal Alcohol Spectrum Disorders diagnosis, Hair chemistry, Humans, Infant, Newborn, Mass Spectrometry methods, Maternal Exposure, Nails chemistry, Pregnancy, Alcohol Drinking metabolism, Ethanol metabolism, Glucuronates analysis, Meconium chemistry
- Abstract
Background: The deleterious effects exerted by prenatal ethanol exposure include physical, mental, behavioral, and/or learning disabilities that are included in the term fetal alcohol spectrum disorder. The measurement of ethylglucuronide (EtG) in alternative biological matrices, including neonatal and maternal hair, neonatal meconium, and maternal nails, is receiving increasing interest for the accurate evaluation of the in utero exposure to alcohol., Objective: To evaluate the correlation between EtG in maternal hair and nails with EtG in neonatal meconium to further explore the suitability of these biomarkers in disclosing prenatal exposure to ethanol., Methods: A total of 151 maternal hair strands (0-6 cm), nail clips (2-6 mm), and corresponding neonatal meconium and nails samples were obtained from neonatal wards of 4 Mediterranean public hospitals: Rome, Florence, and Belluno in Italy and Barcelona in Spain. Hair, nails, and meconium were analyzed for the presence of EtG by validated liquid chromatography mass spectrometry assay. Meconium was also analyzed for the presence of fatty acid ethyl esters (FAEEs) as a complementary biomarker of potential in utero exposure to alcohol., Results: Eighteen newborns resulted in utero exposed to maternal alcohol consumption by FAEE testing in meconium with EtG values between 0.5 and 1.5 nmol/g. Unfortunately, none of these cases were confirmed by the presence of EtG in maternal hair and nails samples, which resulted all negative to this biomarker., Discussion and Conclusions: The results confirm that FAEEs and EtG in meconium are the best biomarkers to assess in utero exposure to maternal alcohol. EtG in hair and nails are not good biomarkers to disclose alcohol consumption lower than on daily basis and lower than 1-2 alcoholic units per day.
- Published
- 2013
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7. Usefulness of sweat testing for the detection of methylphenidate after fast- and extended-release drug administration: a pilot study.
- Author
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Marchei E, Farré M, Pardo R, Garcia-Algar O, Pellegrini M, Pacifici R, and Pichini S
- Subjects
- Central Nervous System Stimulants administration & dosage, Central Nervous System Stimulants pharmacokinetics, Delayed-Action Preparations, Dose-Response Relationship, Drug, Humans, Male, Methylphenidate administration & dosage, Methylphenidate analogs & derivatives, Methylphenidate pharmacokinetics, Pilot Projects, Young Adult, Central Nervous System Stimulants analysis, Methylphenidate analysis, Substance Abuse Detection methods, Sweat chemistry
- Abstract
The pharmacokinetics of methylphenidate (MPH), a prescription amphetamine derivative used in the treatment of attention-deficit hyperactivity disorder, has been amply described in conventional biological matrices. Recently, the excretion of MPH and its principal metabolite, ritalinic acid (RA) in oral fluid and plasma after a single drug administration has been described. The aim of this study was to describe the excretion of MPH and RA in sweat after the administration of a single dose of either fast-release or extended-release MPH. Three male subjects received 2 simultaneous oral doses of 10 mg fast-release MPH, and 1 male subject received one dose of 20 mg extended-release MPH. Sweat patches were applied to the back of each participant and removed at timed intervals. MPH and RA were determined in patches using a previously validated liquid chromatography-electrospray ionization mass spectrometric method. MPH was detected in sweat after the administration of fast- and extended-release formulations. For the fast-release formulation, MPH appeared in the sweat patches 2 hours after administration with a maximum of 15.9 nanogram per patch, reached after 24 hours. Mean total MPH excreted was 0.02 mg (about 0.08% of the administered dose). For the extended-release formulation, MPH appeared in the sweat 5 hours after administration and reached a maximum of 34.3 nanogram per patch after 24 hours. Mean total MPH excreted was 0.04 mg (about 0.18% of the administered dose). RA was not detected in either of the sweat patches probably because of its acidic properties. Measuring MPH in sweat patches can be a viable alternative to urine testing for noninvasive monitoring of use and misuse of the drug.
- Published
- 2010
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8. Stability of drugs of abuse in oral fluid collection devices with purpose of external quality assessment schemes.
- Author
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Ventura M, Pichini S, Ventura R, Leal S, Zuccaro P, Pacifici R, and de la Torre R
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- Drug Stability, Humans, Quality Control, Reproducibility of Results, Specimen Handling, Illicit Drugs analysis, Saliva chemistry, Substance Abuse Detection methods
- Abstract
As the stability of drugs of abuse in oral fluid can affect drug testing results, we evaluated this parameter together with recovery for the principal drugs of abuse in two collection devices typically used to ship oral fluid samples to testing laboratories. Two different samples were prepared using Cozart Drug Detection System and Intercept oral fluid collection devices with 600 ng/mL of 6-monoacetylmorphine (6-MAM) and cocaine and 240 ng/mL of Delta-tetrahydrocannabinol (THC) and 11-nor-9-carboxy-Delta-tetrahydrocannabinol (THCCOOH). Samples were sent at ambient temperature by courier to the participating laboratories (n = 19) the same day of preparation. Samples were analyzed upon reception (about 48-72 hours after shipment). Percent coefficients of variation, calculated using robust mean and robust standard deviation, were around 30% for all analytes, except for THCCOOH in both samples (between 50% and 80%) and THC in 1 sample (50%). Percent coefficients of variation were also high (between 50% and 70%) for morphine and benzoylecgonine, formed after 6-MAM and cocaine spontaneous hydrolysis. On average, 9%-12% 6-MAM was converted to morphine and between 26% and 41% cocaine to benzoylecgonine. Good recoveries were observed for the acid metabolite of THC in both collection devices, whereas THC was always scarcely recovered. Depending on the collection device used, obtained results may confound the interpretation and estimation of blood drug concentration, given an oral fluid drug concentration and subsequent consideration of time elapsing from drug consumption.
- Published
- 2009
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9. Liquid chromatography with tandem mass spectrometric detection for the measurement of ethyl glucuronide and ethyl sulfate in meconium: new biomarkers of gestational ethanol exposure?
- Author
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Morini L, Marchei E, Pellegrini M, Groppi A, Stramesi C, Vagnarelli F, Garcia-Algar O, Pacifici R, and Pichini S
- Subjects
- Alcohol Drinking, Biomarkers, Female, Glucuronates metabolism, Humans, Infant, Newborn, Pregnancy, Reproducibility of Results, Sensitivity and Specificity, Substance Abuse Detection methods, Sulfuric Acid Esters metabolism, Chromatography, Liquid methods, Ethanol metabolism, Glucuronates analysis, Meconium chemistry, Sulfuric Acid Esters analysis, Tandem Mass Spectrometry methods
- Abstract
A liquid chromatography tandem mass spectrometric (LC-MS/MS) method with postcolumn addition of acetonitrile for the determination of ethyl glucuronide (EtG) and ethyl sulfate (EtS) in meconium was developed and validated using pentadeuterated EtG and pentadeuterated EtS as internal standards. The analytes were extracted from the matrix by acetonitrile, concentrated by solid phase extraction, separated using a reversed-phase chromatographic column, and quantified within 9 minutes. Lower limits of quantification were 5 and 1 ng/g meconium for EtG and EtS, respectively. Calibration curves were linear from lower limits of quantifications to 500 ng/g, with a minimum r > 0.999. At 3 concentrations spanning the linear dynamic range of the assay, mean recoveries ranged between 78.7% and 96.8% for EtG and between 72.1% and 95.6% for EtS. Inaccuracy was better than 8.1%, with intra-assay and interassay imprecision better than 7.2% and 10.5%, respectively. Matrix effects (ion suppression/enhancement) were found to be negligible. The analytes of interest were stable at room temperature, at 4 degrees C, when exposed to 3 freeze-thaw cycles, and when stored at -20 degrees C for up to 6 months. This sensitive and specific method was used to assess the presence of these alcohol biomarkers in meconium samples from 2 different city cohorts.
- Published
- 2008
- Full Text
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10. Alarming prevalence of fetal alcohol exposure in a Mediterranean city.
- Author
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Garcia-Algar O, Kulaga V, Gareri J, Koren G, Vall O, Zuccaro P, Pacifici R, and Pichini S
- Subjects
- Adult, Cohort Studies, Esters, Fatty Acids analysis, Female, Fetal Alcohol Spectrum Disorders epidemiology, Humans, Infant, Newborn, Meconium chemistry, Mediterranean Region epidemiology, Pregnancy, Prevalence, Spain, Alcohol Drinking metabolism, Alcoholism epidemiology, Maternal-Fetal Exchange, Pregnancy Complications epidemiology, Prenatal Exposure Delayed Effects, Substance Abuse Detection
- Abstract
The prevalence of gestational ethanol exposure and subsequent fetal exposure has been assessed in a cohort of mother-infant dyads in a Mediterranean city (Barcelona, Spain) by meconium analysis of fatty acid ethyl esters (FAEEs) after showing in this population a high prevalence of meconium opiates (8.7%), cocaine (4.4%), and cannabis (5.3%). Of the 353 meconium samples analyzed for FAEEs, 159 (45%) contained a total amount of seven FAEEs equal or above 2 nmol/g meconium, the cutoff internationally accepted to differentiate heavy maternal alcohol consumption during pregnancy from occasional use or no use at all. No parental sociodemographic differences or maternal features differentiated exposed from unexposed newborns. The prevalence of gestational consumption of ethanol was similar between women using and not using drugs of abuse during pregnancy (45.7% and 44.7% of samples with total FAEEs equal or higher than 2 nmol/g meconium, respectively). Meconium samples from newborns exposed in utero to ethanol, and positive for at least one illicit drug (cocaine, opiates, or cannabis), had total FAEEs and five of nine individual FAEEs statistically higher than the meconium samples that were negative for the most frequently used illicit drugs of abuse. Among the most prevalent FAEEs, oleic acid ethyl ester showed the best correlation to total FAEE concentration followed by palmitoleic acid ethyl ester . This study, which highlights a 45% ethanol consumption during pregnancy in a low socioeconomic status cohort, may serve as an eye opener for Europeans that gestational alcohol exposure is not endemic only in areas outside of Europe.
- Published
- 2008
- Full Text
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11. Stability studies of principal illicit drugs in oral fluid: preparation of reference materials for external quality assessment schemes.
- Author
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Ventura M, Pichini S, Ventura R, Zuccaro P, Pacifici R, and de la Torre R
- Subjects
- Cocaine chemistry, Drug Storage, Humans, Morphine Derivatives chemistry, Quality Control, Reference Values, Substance Abuse Detection standards, Illicit Drugs chemistry, Saliva chemistry, Substance-Related Disorders diagnosis
- Abstract
Data on the stability of drugs of abuse in oral fluid are needed to define the optimal transportation and storage conditions when this biological fluid has to be used for off-site screening and confirmation analyses, as well as in the preparation of reference material for external quality assessment schemes. The short-term and long-term stability of opiates, cocaine, amphetamines, and methylenedioxy derivatives in unstimulated oral fluid was evaluated in different storage conditions, with and without the addition of citrate buffer and sodium azide. Short-term stability was evaluated at 25 degrees C and 37 degrees C for up to 7 days. Long-term stability was evaluated at different time intervals for up to 2 months at 4 degrees C and -20 degrees C. The effect of three different freezing and thawing cycles was also studied. No significant loss of amphetamines and methylenedioxy derivatives, morphine, codeine, and benzoylecgonine was observed under any of the investigated conditions. Conversely, hydrolysis of the ester bonds of cocaine and 6-MAM, leading to the formation of benzoylecgonine and morphine, respectively, was observed under all the applied conditions when oral fluid was not buffered and preserved. The addition of citrate buffer (pH, 4) and sodium azide (0.1%) to oral fluid prevented their degradation during up to 7 days of storage at 25 degrees C and 37 degrees C and up to 2 months at 4 degrees C and -20 degrees C. The stability of the principal illicit drugs spiked in buffered and stabilized oral fluid is adequate for transportation of collected samples at ambient temperature and for shipment and storage of reference materials for external quality assessment schemes.
- Published
- 2007
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12. Disposition of gamma-hydroxybutyric acid in conventional and nonconventional biologic fluids after single drug administration: issues in methodology and drug monitoring.
- Author
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Abanades S, Farré M, Segura M, Pichini S, Pastor A, Pacifici R, Pellegrini M, and de la Torre R
- Subjects
- Administration, Oral, Adult, Area Under Curve, Drug Stability, Half-Life, Humans, Hydroxybutyrates blood, Hydroxybutyrates urine, Male, Reproducibility of Results, Saliva metabolism, Sweat metabolism, Temperature, Time Factors, Tissue Distribution, Drug Monitoring methods, Hydroxybutyrates pharmacokinetics
- Abstract
Little controlled drug administration data are available to aid in the interpretation of gamma-hydroxybutyric acid (GHB) distribution in conventional and nonconventional fluids and the potential correlation between the pharmacokinetics of GHB and drug effects. Single oral sodium GHB doses of 50 mg/kg were administered to five volunteers. Plasma, oral fluid, urine, and sweat were analyzed for GHB by gas chromatography-mass spectrometry. GHB stability in plasma was studied at different storage temperatures. Subjective effects were measured using a set of 13 different visual analog scales. Mean peak GHB plasma concentrations at 30 minutes were 83.1 microg/mL. After the absorption phase, concentrations declined to mean values of 0.9 microg/mL at 6 hours. GHB was found in oral fluid at peak value concentrations equivalent to one third to one fourth of those found in plasma. The oral fluid-to-plasma ratio varied two fold in the 1- to 6-hour time range but always was lower than unit. The mean half-life (t1/2) of GHB was approximately 0.7 hour in plasma and approximately 1.2 hours in oral fluid. GHB urinary excretion is less than 2% of the dose administered. GHB was also detected in sweat at low concentrations. GHB showed a mixed sedative-stimulant pattern with subjective effects peaking between 1 and 1.5 hours after drug administration and lasting for 2 hours. Oral fluid and sweat appeared not to be suitable biologic matrices for monitoring GHB consumption. GHB-mediated subjective effects are related to GHB plasma concentrations.
- Published
- 2007
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13. Quantification of Delta9-tetrahydrocannabinol and its major metabolites in meconium by gas chromatographic-mass spectrometric assay: assay validation and preliminary results of the "meconium project".
- Author
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Marchei E, Pellegrini M, Pacifici R, Palmi I, Lozano J, García-Algar O, and Pichini S
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- Dronabinol analysis, Female, Humans, Infant, Newborn, Maternal-Fetal Exchange, Pregnancy, Reproducibility of Results, Dronabinol metabolism, Gas Chromatography-Mass Spectrometry methods, Meconium chemistry
- Abstract
A rapid and simple procedure based on gas chromatography-mass spectrometry (GC-MS) is described for determination of Delta-tetrahydrocannabinol (THC), 11-hydroxy-Delta-tetrahydrocannabinol (THC-OH) and 11-nor-Delta-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in meconium using Delta-tetrahydrocannabinol (Delta-THC) and deuterated THC-COOH as internal standards. The biological matrix was subjected to liquid-liquid extraction after enzyme hydrolysis for conjugated analytes.Chromatography was performed on a fused silica capillary column and analytes were determined in the selected-ion-monitoring (SIM) mode. The method was validated in the range 20 to 500 microg/g using 1g of meconium per assay. The method was applied to the analysis of meconium in a cohort of newborns to assess eventual fetal exposure to cannabis. Within positive samples, THC-COOH and THC-OH (range: 33.7 to 182.1 and 20.7 to 493.3 microg/g, respectively) were both present in the majority of cases with only 1 specimen with THC-OH as the most abundant metabolite and 2 with THC only.
- Published
- 2006
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14. Assessment of chronic exposure to MDMA in a group of consumers by segmental hair analysis.
- Author
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Pichini S, Poudevida S, Pujadas M, Menoyo E, Pacifici R, Farré M, and de la Torre R
- Subjects
- Adolescent, Adult, Case-Control Studies, Humans, Surveys and Questionnaires, Hair chemistry, Hallucinogens analysis, N-Methyl-3,4-methylenedioxyamphetamine analysis, Substance Abuse Detection methods
- Abstract
The suitability of segmental hair analysis of MDMA to monitor past chronic exposure to the drug was investigated in a follow-up study of ecstasy consumers. The purpose, among others, was to look for an objective biomarker of the history of drug consumption. Thirteen naturally colored hair samples were used to assess possible association between hair concentration of MDMA in 1-, 5-, and 9-cm segments and self-reported use in the last 1, 6, and 12 months. Agreement between the self-reported data given by the subjects on their "ecstasy" use in the previous month and MDMA hair concentration was good (r = 0.92) in all the examined subjects, with the exception of 2 individuals who declared a high consumption of the drug (12 tablets in the last month). When comparing the subjects' declaration of tablets consumed per month within the last 6 months, concordance with the hair MDMA values decreased and no correlation seemed to exist between the mean number of tablets consumed in the last 12 months and the concentration of MDMA in hair. However, when grouping subjects with a similar level of declared drug use (independently of whether in the previous month, last 6 months and last 12 months) and comparing the data with the mean MDMA concentrations found in the corresponding hair segments, an excellent level of agreement was found in groups of subjects consuming <5 tablets of MDMA per month (r = 0.93). Although the present findings were obtained from a small group of individuals and are intended as preliminary results, we can conclude that a cutoff of 0.5 ng MDMA per mg hair seems reasonable to assess drug consumption, unless the level of consumption was once per month in the last 12 months. Doubling the monthly consumption increases hair MDMA by around 1 ng/mg hair up to a level of 4 consumed tablets a month. It does not seem possible to draw definitive conclusions from higher concentrations in hair samples.
- Published
- 2006
- Full Text
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15. Plasma concentrations of the enantiomers of fluoxetine and norfluoxetine: sources of variability and preliminary observations on relations with clinical response.
- Author
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Jannuzzi G, Gatti G, Magni P, Spina E, Pacifici R, Zuccaro P, Torta R, Guarneri L, and Perucca E
- Subjects
- Adolescent, Adult, Aged, Analysis of Variance, Depression blood, Depression drug therapy, Female, Fluoxetine administration & dosage, Fluoxetine chemistry, Humans, Male, Mental Disorders drug therapy, Middle Aged, Statistics, Nonparametric, Stereoisomerism, Fluoxetine analogs & derivatives, Fluoxetine blood, Mental Disorders blood
- Abstract
Factors affecting the plasma concentrations of the R- and S-enantiomers of fluoxetine and norfluoxetine were investigated in 131 adult patients receiving long-term fluoxetine, of 10 to 60 mg/d (mean, 24 +/- 10 mg/d). Plasma concentration values (geometric means, CI 95%) in these patients were 186 (156, 223) nmol/L for S-fluoxetine, 67 (58, 77) nmol/L for R-fluoxetine, 247 (212, 287) nmol/L for S-norfluoxetine, and 118 (102, 137) nmol/L for R-norfluoxetine. The difference between the concentrations of the respective R- and S-enantiomers was statistically significant ( P< 0.0001) for both the parent drug and the demethylated metabolite. A significant correlation was found between the concentrations of each enantiomer and the prescribed daily dosage (r = 0.44, P< 0.0001 for S-fluoxetine; r = 0.48, P < 0.0001 for R-fluoxetine; r = 0.36, < 0.0001 for S-norfluoxetine; r = 0.32, P = 0.0003 for R-norfluoxetine), but the variability in concentration at any given dosage was considerable. When an iterative model based on multiple polynomial regressions was applied to determine the potential contributions of dosage, age, gender, body weight, and concomitant medication to the variability in the plasma concentration of the enantiomers, dosage was consistently found to provide the greatest predictive value. The predictive value of the model could be consistently improved when concentrations of other enantiomers were included as covariates. Of 58 patients with depressive symptoms for whom evaluation of clinical response (CGI scale) was available, 33 (57%) responded favorably to treatment. The plasma levels of individual enantiomers and of the active moiety (ActM, sum of the concentrations of R-fluoxetine, S-fluoxetine, and S-norfluoxetine) in these patients did not differ significantly from those found in patients with unsatisfactory therapeutic response. Likewise, the concentrations of individual enantiomers and of the ActM were similar in patients with or without adverse effects. Overall, these results demonstrate that the pharmacokinetics of fluoxetine and norfluoxetine exhibit marked stereoselectivity and considerable interpatient variability, which could not be explained by differences in gender, age, or comedication. In addition, a considerable variability was found in the enantiomers' concentrations associated with a favorable therapeutic response.
- Published
- 2002
- Full Text
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16. Nicotine, cotinine, and trans-3-hydroxycotinine levels in seminal plasma of smokers: effects on sperm parameters.
- Author
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Pacifici R, Altieri I, Gandini L, Lenzi A, Pichini S, Rosa M, Zuccaro P, and Dondero F
- Subjects
- Adolescent, Adult, Caffeine adverse effects, Chromatography, High Pressure Liquid, Cotinine blood, Humans, Male, Middle Aged, Nicotine blood, Regression Analysis, Semen chemistry, Semen drug effects, Smoking blood, Spermatozoa physiology, Cotinine analogs & derivatives, Cotinine metabolism, Nicotine metabolism, Semen metabolism, Smoking adverse effects, Smoking metabolism, Spermatozoa drug effects
- Abstract
Sperm samples from 44 cigarette smokers and 50 nonsmokers attending an infertility clinic were examined by high-performance liquid chromatography (HPLC) assay and HPLC-mass spectrometry for the presence of nicotine (NIC), cotinine (COT), and trans-3'-hydroxycotinine (THOC) in seminal plasma. Smokers were found to have levels of COT and THOC in seminal plasma that were similar to those found in serum. The level of NIC was significantly increased in seminal plasma compared to serum. Total motility of spermatozoa was significantly and negatively correlated to COT and THOC levels in seminal plasma. Forward motility of spermatozoa was correlated only with cotinine semen levels. On the basis of these results, we suggest that the presence of tobacco smoke constituents in seminal plasma could provide a warning of the adverse effects of cigarette smoke on the physiology of reproduction.
- Published
- 1993
- Full Text
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17. Fat body mass and pharmacokinetics of oral 6-mercaptopurine in children with acute lymphoblastic leukemia.
- Author
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Zuccaro P, Guandalini S, Pacifici R, Pichini S, Di Martino L, Guiducci M, Giuliano M, Di Tullio MT, and Pettoello Mantovani M
- Subjects
- Administration, Oral, Adolescent, Biological Availability, Child, Child, Preschool, Female, Humans, Intestinal Absorption drug effects, Male, Mercaptopurine administration & dosage, Mercaptopurine therapeutic use, Precursor Cell Lymphoblastic Leukemia-Lymphoma metabolism, Body Weight, Mercaptopurine pharmacokinetics, Precursor Cell Lymphoblastic Leukemia-Lymphoma drug therapy
- Abstract
To evaluate the reasons for the wide variability in bioavailability of orally administered 6-mercaptopurine in children with acute lymphoblastic leukemia, we studied several pharmacokinetic parameters of the drug in 18 affected children receiving remission maintenance therapy, and compared them with their anthropometric data and with the results of intestinal function tests. No correlation was found between estimates of small intestinal absorption (the oral lactose tolerance test and 1 h blood xylose test) and 6-mercaptopurine serum levels. Of the anthropometric measurements considered, only the weight/height percentile (an index of the fat body mass) strongly and linearly correlated with the area under the curve of 6-mercaptopurine. The dose of 75 mg of 6-mercaptopurine/m2 of body surface resulted in higher serum concentrations in children below the 75th percentile than in those with a weight/height ratio exceeding the 75th percentile. In conclusion, these data caution about the risk of underdosing 6-mercaptopurine in overweight children when administering it on the basis of body surface area.
- Published
- 1991
- Full Text
- View/download PDF
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