Biomedical subjects

Renzo Bagnati

Publications and source records attributed to Renzo Bagnati.

9 recordsLinked to original sources

PubMed2006

Identification and measurement of illicit drugs and their metabolites in urban wastewater by liquid chromatography-tandem mass spectrometry.

Residues of illicit drugs and their metabolites that are excreted by humans may flow into and through wastewater treatment plants. The aim of this study was to develop a method for the determination of cocaine, amphetamines, morphine, cannabinoids, methadone, and some of their metabolites in wastewater. Composite 24-h samples from urban treatment plants were enriched with deuterated internal standards before solid-phase extraction. High-pressure liquid chromatography tandem mass spectrometry with multiple reaction monitoring was used for quantitation. Recoveries were generally higher than 80%, and limits of quantifications were in the low nanograms-per-liter range for untreated and treated wastewater. The overall variability of the method was lower than 10% for untreated and 5% for treated wastewater. The method was applied to wastewater samples coming from two treatment plants in Italy and Switzerland. Quantification ranges were found to be 0.2-1 microg/L for cocaine and its metabolite benzoylecgonine, 80-200 ng/L for morphine, 10 ng/L for 6-acetylmorphine, 60-90 ng/L for 11-nor-9-carboxy-Delta9-tetrahydrocannabinol, 10-90 ng/L for methadone and its main metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, and lower than 20 ng/L for amphetamines. As previously reported for cocaine, this method could be useful to estimate and monitor drug consumption in the population in real time, helping social scientists and authorities to combat drug abuse.

Chromatography, Liquid↗

PubMed2006

Removal of pharmaceuticals in sewage treatment plants in Italy.

A listing of "priority pharmaceuticals" for human use in Italy resulted in the selection of 26 pharmaceuticals, belonging to 11 therapeutic classes. They were analyzed by liquid chromatography-tandem mass spectrometry, their occurrence was assessed in six sewage treatment plants (STPs), and the loads and the removal rates (RR) were studied. Total loads ranged from 1.5 to 4.5 g/day/1000 inhabitants in influents and 1.0 and 3.0 g/day/1000 inhabitants in effluents. Total RR in STPs were mostly lower than 40%. Pharmaceuticals could be divided into three groups according to their behavior in STPs: one group with RR higher in summer than in winter, one group with RR similar in summer and winter, and a last group not removed. Last, we studied the distribution and fate of residual pharmaceuticals in the surface waters receiving the effluents of the STPs and identified degradation and sorption as the major factors affecting attenuation. Ciprofloxacin, ofloxacin, sulfamethoxazole (antibiotics), atenolol (cardiovascular drug), ibuprofen (antiinflammatory), furosemide, hydrochlorothiazide (diuretics), ranitidine (gastrointestinal drug), and bezafibrate (lipid regulator) were the most abundant residual drugs, thus those of environmental concern.

Drug Residues↗

PubMed2006

Pharmaceuticals in the environment in Italy: causes, occurrence, effects and control.

BACKGROUND, AIM AND SCOPE: Environmental contamination by pharmaceuticals is an emerging issue. Until recently, information on medicinal substances released into the environment was scant, but several studies have now been published. Data are, however, usually scattered and a systematic approach to this subject is generally lacking. Moreover, because of differences in the prevalence of diseases, treatment habits and options, or simply for market reasons, the pollution profile can differ significantly in different countries. The aim of this work is to review the papers dealing with environmental contamination by pharmaceuticals in Italy, with the aim of providing a comprehensive view on a national scale. METHODS: Papers related to environmental contamination by pharmaceuticals in Italy were reviewed, in order to offer a comprehensive view of this subject. Topics included analysis, occurrence, monitoring, modelling, treatment, control of the emissions, and ecotoxicological effects of pharmaceuticals in the environment. RESULTS AND CONCLUSION: The literature suggests that pharmaceuticals are widespread contaminants, entering the environment from a myriad of scattered points. Patients, in case of drugs for human use, or animals for veterinary drugs, are the main sources of contamination. Pharmaceuticals can be ranked according to environmental loads, predicted by multiplying sales figures by the rate of metabolism in man or animals. Priority pharmaceuticals, i.e. the molecules of concern for the environment, can be measured in waste and surface water by liquid chromatography-tandem mass spectrometry, and the loads detected are generally comparable to the predicted ones. Pharmaceuticals are designed to stimulate a response in humans and animals at low doses, with a very specific target, so the implications for human health and the environment need to be assessed. In vitro and in vivo studies suggest that pharmaceutical principles, taken singularly or in combinations, and concentrations close to those detected in the environment, may have ecotoxicological effects. The sewage system is an important point in the control of contamination, but sewage treatment plants are not able efficiently to abate a substantial part of water-borne pharmaceuticals. Several variables play a role, however, in the processes of waste water treatment, and could be specifically adjusted to improve the efficiency of drug abatement, mitigating the potential environmental hazards. RECOMMENDATION AND PERSPECTIVE: Pharmaceuticals in the environment are becoming a subject of global concern, with potential environmental consequences. Further knowledge of the causes, occurrence and effects of drugs as environmental pollutants is necessary for a better understanding of this ecological issue, as well as to improve abatement strategies, and to mitigate subtle environmental consequences.

Animals↗

PubMed2005

A multiresidue analytical method using solid-phase extraction and high-pressure liquid chromatography tandem mass spectrometry to measure pharmaceuticals of different therapeutic classes in urban wastewaters.

An analytical method with two extraction steps has been developed and validated for the simultaneous determination of 30 pharmaceuticals belonging to various therapeutic categories in urban wastewater. The aim was to boost the little available information on drugs' fates in sewage treatment plants (STPs) and in the receiving surface water. Aqueous samples were divided into two aliquots, each extracted by a different solid-phase extraction (SPE) method and analysed by reversed-phase liquid chromatography tandem mass spectrometry (HPLC-MS-MS). Recoveries of the pharmaceuticals were mostly greater than 70% and the overall variability of the method was below 8%. The instrumental quantification limit (IQL) varied between 30 and 400 pg injected, and the limits of quantification (LOQ) were in the low ng/L range. Nineteen pharmaceuticals were detected in concentrations between 0.5 and 2000 ng/L in effluents collected from several STPs in Italy. Atenolol, ciprofloxacin, furosemide, hydrochlorothiazide, ofloxacin, ranitidine and sulphamethoxazole were the most abundant compounds. The present analytical method was useful to check for pharmaceuticals in various Italian STPs and to identify the most abundant compounds.

Chromatography, High Pressure Liquid↗

PubMed2005

Cocaine in surface waters: a new evidence-based tool to monitor community drug abuse.

BACKGROUND: Cocaine use seems to be increasing in some urban areas worldwide, but it is not straightforward to determine the real extent of this phenomenon. Trends in drug abuse are currently estimated indirectly, mainly by large-scale social, medical, and crime statistics that may be biased or too generic. We thus tested a more direct approach based on 'field' evidence of cocaine use by the general population. METHODS: Cocaine and its main urinary metabolite (benzoylecgonine, BE) were measured by mass spectrometry in water samples collected from the River Po and urban waste water treatment plants of medium-size Italian cities. Drug concentration, water flow rate, and population at each site were used to estimate local cocaine consumption. RESULTS: We showed that cocaine and BE are present, and measurable, in surface waters of populated areas. The largest Italian river, the Po, with a five-million people catchment basin, steadily carried the equivalent of about 4 kg cocaine per day. This would imply an average daily use of at least 27 +/- 5 doses (100 mg each) for every 1000 young adults, an estimate that greatly exceeds official national figures. Data from waste water treatment plants serving medium-size Italian cities were consistent with this figure. CONCLUSION: This paper shows for the first time that an illicit drug, cocaine, is present in the aquatic environment, namely untreated urban waste water and a major river. We used environmental cocaine levels for estimating collective consumption of the drug, an approach with the unique potential ability to monitor local drug abuse trends in real time, while preserving the anonymity of individuals. The method tested here--in principle extendable to other drugs of abuse--might be further refined to become a standardized, objective tool for monitoring drug abuse.

Adult↗

PubMed2005

Proteome analysis for the identification of in vivo estrogen-regulated proteins in bone.

Estrogen deficiency results in a reduced bone mass, which can be prevented by treatment with estrogens. This study used a proteomic approach for the first time to obtain a global perspective of estrogens' effects on whole-bone proteins. Bone proteome profiles were examined in three groups of mice: (1) sham-operated with normal ovarian functions, (2) ovariectomised and (3) ovariectomised with estrogen replacement therapy. Bone proteins extracted from the humerus were separated by 2-DE and visualised by CBB colloidal staining. Spot detection and quantification was done by image analysis. Differentially expressed proteins were identified by MS and database search, using peptide mass fingerprint and peptide sequence analysis. Differential expression analysis in the three experimental groups showed significant changes for 14 proteins. These included proteins related to bone metabolism, cytoskeleton components and energy metabolic pathways. Our data suggest that some proteins related to cytoskeleton and to energy pathways, such as tropomyosins, aconitase 2 and enolase beta, might be new molecular targets responsive to the effects of estrogen. Differentially expressed proteins identified in this model may offer a useful starting point for elucidating novel aspects of the pleiotropic effects of estrogens on bone.

Animals↗

PubMed2004

Methodological approaches for studying pharmaceuticals in the environment by comparing predicted and measured concentrations in River Po, Italy.

A predictive approach seems useful to study human and veterinary pharmaceuticals in the environment and provide an idea of overall levels of contamination, so as to restrict monitoring to those molecules which are most likely to represent possible environmental contaminants. Predicted environmental concentrations (PECs) can be calculated by a mass balance approach, while a recent proposal from the European Agency for the Evaluation of Medicinal Products (EMEA) suggests an alternative method for calculating PEC for each pharmaceutical and then focusing further work on molecules with high PEC values. We used the results of monitoring campaigns on the River Po, in Northern Italy, to assess the accuracy of predictive models with measured environmental concentrations (MECs). The comparison indicated that in some cases a refined PEC value can provide a good approximation of the MEC. In other cases PECs substantially differed from the MECs, particularly when there were not enough data to estimate the environmental fate of the molecule. Predictive models might therefore be useful for studying pharmaceuticals in the environment, providing enough experimental data is available on the environmental fate of the molecules.

Environmental Monitoring↗

PubMed2002

Limbic seizures induce P-glycoprotein in rodent brain: functional implications for pharmacoresistance.

The causes and mechanisms underlying multidrug resistance (MDR) in epilepsy are still elusive and may depend on inadequate drug concentration in crucial brain areas. We studied whether limbic seizures or anticonvulsant drug treatments in rodents enhance the brain expression of the MDR gene (mdr) encoding a permeability glycoprotein (P-gp) involved in MDR to various cancer chemotherapeutic agents. We also investigated whether changes in P-gp levels affect anticonvulsant drug concentrations in the brain. Mdr mRNA measured by RT-PCR increased by 85% on average in the mouse hippocampus 3-24 hr after kainic acid-induced limbic seizures, returning to control levels by 72 hr. Treatment with therapeutic doses of phenytoin or carbamazepine for 7 d did not change mdr mRNA expression in the mouse hippocampus 1-72 hr after the last drug administration. Six hours after seizures, the brain/plasma ratio of phenytoin was reduced by 30% and its extracellular concentration estimated by microdialysis was increased by twofold compared with control mice. Knock-out mice (mdr1a/b -/-) lacking P-gp protein showed a 46% increase in phenytoin concentrations in the hippocampus 1 and 4 hr after injection compared with wild-type mice. A significant 23% increase was found in the cerebellum at 1 hr and in the cortex at 4 hr. Carbamazepine concentrations were measurable in the hippocampus at 3 hr in mdr1a/b -/- mice, whereas they were undetectable at the same time interval in wild-type mice. In rats having spontaneous seizures 3 months after electrically induced status epilepticus, mdr1 mRNA levels were enhanced by 1.8-fold and fivefold on average in the hippocampus and entorhinal cortex, respectively. Thus, changes in P-gp mRNA levels occur in limbic areas after both acute and chronic epileptic activity. P-gp alterations significantly affect antiepileptic drugs concentrations in the brain, suggesting that seizure-induced mdr mRNA expression contributes to MDR in epilepsy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2002

Identification of metabolites from type III F2-isoprostane diastereoisomers by mass spectrometry.

F(2)-isoprostanes (F(2)-iPs) are prostaglandin (PG)-like products of non-enzymatic free radical-catalyzed peroxidation of arachidonic acid that are now widely used as indices of lipid peroxidation in vivo. Knowledge of the metabolic fate of F(2)-iPs in vivo is still scant, despite its importance for defining their overall formation and biological effects in vivo. Type III F(2)-iPs, which are diastereoisomers of cyclooxygenase-derived PGF(2alpha), may be metabolized through the pathways of PG metabolism. We therefore studied the in vitro metabolism of eight synthetic Type III F(2)-iP diastereoisomers in comparison with PGF(2alpha). We used gas chromatography-mass spectrometry and high performance liquid chromatography-electrospray-tandem mass spectrometry for structural identification of metabolites formed after incubation of the various compounds with isolated rat hepatocytes. PGF(2alpha) was metabolized to several known products, resulting from a combination of beta-oxidation, reduction of Delta(5) and/or Delta(13) double bonds, and 15-OH oxidation, plus other novel products deriving from conjugation with taurine of PGF(2alpha) and its metabolites. Of the eight F(2)-iP diastereoisomers, some were processed similarly to PGF(2alpha), whereas others showed peculiar metabolic profiles according to specific stereochemical configurations. These data represent the first evidence of biodegradation of selected Type III F(2)-iP isomers other than 8-epi-PGF(2alpha), through known and novel pathways of PGF(2alpha) metabolism. The analytical characterization of these products may serve as a basis for identifying the most significant products formed in vivo.

Carbohydrate Sequence↗