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Objective Management of vitamin K antagonists (VKAs) is difficult, and overdoses can have dramatic hemorrhagic consequences. The adverse drug event (ADE) scorecards is a tool intended for the detection and description of adverse drug reaction/ADE developed during a European computerized medical data processing project. It is used in a quality assurance process. Our objective was to evaluate the performance of the ADE scorecards in the detection of the contributing factors for VKA overdoses, among the cases where a VKA overdose is observed. Methods Twenty-eight rules allow the detection of VKA treatment overdose related to drug or a clinical situation. They were applied on 14,748 electronic medical records from a community hospital. Among 582 records including a VKA prescription, 59 cases of VKA overdoses (international normalized ratio ≥ 5) during the hospital stay have been identified. The ADE scorecards detected 49 of them. We evaluated the positive predictive value and sensitivity of these rules, by an expert review of the cases. Results The expert review confirmed the contribution of a detected risk factor to the VKA overdose in 11 cases. Therefore, the precision of the rules is 22.4%. The sensitivity is 84.6%. The risk factors were mainly infection and amiodarone introduction. The 4 cases of clinical injury related to a drug were properly designated by the rules. Conclusions Our study shows the great potential of the ADE scorecards for detecting cofactors of VKA overdoses and gives an argument to include complex rules in the knowledge bases used for the detection and identification of ADEs in large medical databases.

Introduction The prescription of psychotropic drugs to older patients in a hospital setting has not been extensively characterized. The objective was to describe the inappropriate co-prescriptions of psychotropic drugs in hospitalized patients aged 75 and over. Methods By analysing the medical database from 222-bed general hospital in France, we reviewed a total of 11,929 stays of at least 3 days by patients aged 75 and over. Prescriptions and co-prescriptions of psychotropic drugs were identified automatically. Anticholinergic drugs with sedative effects were considered as psychotropic drugs. An expert review was performed for stays with the co-prescription of three or more psychotropic drugs to identify inappropriate co-prescriptions. Results Administration of a psychotropic drug was identified in 5475 stays (45.9% of the total number of stays), of which 1526 (12.8% of the total) featured at least one co-prescription. Co-prescriptions of three or more psychotropic drugs for at least 3 days were identified in 374 stays (3.1% of the total). Most of these co-prescriptions ( n =334; 89.2%) were considered inappropriate because of the combination of at least two drugs from the same psychotropic class ( n =269), the absence of a clear indication for a psychotropic drug ( n =173) and a history of falls ( n =86). However, the co-prescriptions were maintained after hospital discharge in 77.4% of cases. Conclusion The co-prescriptions of psychotropic drugs should be re-evaluated in older hospitalized patients.

Drug-induced hyperkalemia is a frequent and severe complication in the hospital setting. Other risk factors may also induce hyperkalemia but the combination of drugs and precipitating factors has not been extensively studied. The aim was to identify drug-induced hyperkalemia events in hospitalized older patients and to describe their combinations with precipitating factors. Two experts independently analyzed retrospective data of patients aged 75 years or more. Experts identified 471 hyperkalemia events and concluded that 379 (80.5%) were induced by drugs. The cause was multifactorial (i.e., at least one drug with a precipitating factor) in 300 (79.2%) of the 379 drug-induced hyperkalemia. Most of the drug-induced hyperkalemia events were avoidable (79.9%)-mainly because of the multifactorial cause (e.g., dosage adaptation during acute kidney injury). Drug-induced hyperkalemia events are frequently combined with precipitating factors in hospitalized older patients and their prevention should focus on these combinations.

International audience; BACKGROUND: Several studies have shown that the prescription of antiplatelet therapy (APT) is associated with an increased risk of oral anticoagulant (OAC) underuse in patients aged 75 years and over with atrial fibrillation (AF). An associated atheromatous disease may be the underlying reason for APT prescription. The objective of the study was to determine whether the association between underuse of OAC and APT prescription was explained by the presence of an atheromatous disease. METHODS AND RESULTS: We performed a retrospective, observational, single-centre study between 2009 and 2013 based on administrative data. Patients aged 75 years and over with non-valvular AF were identified in a database of 72,090 hospital stays. Prescriptions of anti-thrombotic medications and their association with the presence of atheromatous disease were evaluated by the mean of a logistic regression. A total of 2034 hospital stays were included (mean age 84.3 ± 5.2 years). The overall prevalence of known atheromatous disease was 25.9%. OAC underuse was observed in 58.5% of the stays. In multivariable analysis, the prescription of an APT was associated with an increased risk of OAC underuse [odds ratio (OR) 6.85; 95% confidence interval (CI) 5.50-8.58], independently of the presence of a concomitant known atheromatous disease (OR 0.78; 95% CI 0.60-1.01). Among the 692 stays with APT monotherapy (34.0%), 232 (33.5%) displayed an atheromatous disease. CONCLUSIONS: The underuse of OAC is associated with the prescription of APT in older patients with AF, regardless of the presence or absence of known atheromatous disease. Our results suggest that APT is often inappropriately prescribed instead of OAC.

Aims The prevention of adverse drug events (ADEs) demands co-ordination of different health care professionals. ADE scorecards are a novel approach to raise the team awareness regarding ADE risks and causes. It makes information on numbers and on possible causes of possible ADE cases available to the clinical team. The aim of the study was to investigate the usage and acceptance of ADE scorecards by healthcare professionals and their impact on rates of possible ADEs. Methods ADE scorecards were introduced in three departments of a French hospital. A controlled time series analysis of ADE data was conducted to assess the impact of the ADE scorecards. In addition, qualitative interviews and a standardized survey with all participating staff members were performed. Results Physicians, nurses and pharmacists found ADE scorecards effective to increase medication safety and recommended future usage. The time-series analysis did not show changes in rates of possible ADEs. Conclusion ADE scorecards appear to be useful to raise awareness of ADE-related issues among professionals. Although the evaluation did not show significant reductions of ADE rates, the participating physicians, nurses and pharmacists believed that the ADE scorecards could contribute to increased patient safety and to a reduction in ADE rates. Strategies need to be designed to integrate ADE scorecards better into the clinical routine and to increase the precision of ADE detection.

Medical devices such as perfusion materials in polyvinyl chloride may contain di(2-ethylhexyl)phthalate (DEHP). Several studies have questioned the harmlessness of phthalates, which have been shown to have toxic effects on the reproductive system and general development. This study was designed to assess DEHP exposure in infants and children benefitting from cyclic parenteral nutrition (PN). The results are compared with those obtained from children used as controls and receiving no PN, to estimate the potential risk to this pediatric population, taking into account exposure levels and already published data.Plasmatic concentrations of DEHP were assessed by high-performance liquid chromatography from blood samples taken from 22 children at the start and finish of a 12-hour cyclic PN period and compared with those obtained from 20 control children of comparable age and gender.After a 12-hour cyclic PN period, DEHP migration varied widely among the patients. The concentrations were not quantifiable in 4 children at the start of PN. In 1 child, they were quantifiable neither at the start nor at the end of PN. However, for 17 children, DEHP concentrations were quantifiable at the start of PN and were very variable from one child to another. At the end, DEHP concentrations had significantly but variably increased in these children. No trace of DEHP was found in the blood samples from 20 healthy controls.Considering published data on phthalate toxicity, it would appear advisable to encourage the use of medical devices that are either phthalate or DEHP free.

Plasticizers such as di(2-ethylhexyl) phthalate (DEHP) are added to polyvinyl chloride (PVC) to confer flexibility. However, DEHP is associated with reproductive disorders in humans. Because of its noncovalent bond to the PVC matrix, this plasticizer tends to leach easily. Infants and children undergoing cyclic, long-term parenteral nutrition (PN) could be particularly at risk of potential toxicity from DEHP due to regular exposure. Malondialdehyde (MDA) is one of the most commonly used markers of free radical activity. The purpose of this study was to investigate how long-term exposure to phthalate affects the plasmatic rate of MDA.Studies were performed on 7 randomized infants and children on regular cyclic, long-term PN, and the results were compared with those of 5 nontreated infants. The circulating concentrations of DEHP in children and infants during the PN therapy were measured by high-performance liquid chromatography. The concentrations were assessed before and after the PN session. In the same way, plasma MDA concentrations were measured.The circulating concentrations of DEHP before and after a 10- to 11-hour cyclic PN treatment in 7 infants and children under regular perfusion ranged widely, showing a significant increase after the treatment among all the patients. The same phenomenon observed with the rate of MDA showed that the 2 events are closely dependent. Therefore, long-term exposure to DEHP during cyclic PN raised plasma MDA levels, indicating increased oxidative stress.Long-term exposure to DEHP during PN increased free radical activity in vivo.

Phthalates, used in medical devices (MDs), have been identified as reproductive and developmental toxicants. Their toxicity varies somewhat depending on the specific phthalate and is in part linked to the activation of Peroxisome Proliferating-Activated Receptors (PPARs). So, the use of MDs containing targeted phthalates such as di(2-ethylhexyl) phthalate (DEHP) has been challenged by European directive 2007/47/EC. Therefore, MDs manufacturers were forced to quickly find replacement plasticizers. However, very little toxicological and epidemiological studies are available on human health. So, we proceeded to dock these chemicals in order to identify compounds that are likely to interact with PPARs binding sites. The results obtained are generally very mixed on the harmlessness of these alternatives. Moreover, no data exist on the biological effects of their possible metabolites. As DEHP toxicity resulted mainly from its major metabolites, generalizing the use of these plasticizers without conducting extensive studies on the possible effects on human health of their metabolites seems inconceivable.

The disposition of naltrexone (NLT) (REVIA), an opioid antagonist intended for patients with impaired renal function and with severe intractable itching refractory to regular antipruritic therapy, was characterized. Hemodialysis effects on both efficacy and elimination of NLT also were assessed. We developed a simple, sensitive and selective reverse-phase high-performance liquid chromatographic (HPLC) method for measuring NLT plasma concentration in hemodialysis patients treated to relieve pruritus. NLT and the internal standard, naloxone (NLX) were extracted from plasma using a solid-phase extraction method with sep-pack C18 cartridge. The method was employed to determine both naltrexone pharmacokinetics and dialysability parameters during 4-h in dialyzed patients with chronic renal impairment. Thus, seven patients (2 men, 5 women) with end-stage renal disease and pruritus on regular hemodialysis were included. They received one tablet of NLT (Revia, 50 mg) orally prior dialysis session. The Cmax at the inlet and at the outlet the dialyzer were higher (255+/-117 ng/mL and 206+/-137 ng/ml respectively) in comparison with healthy subjects (9 - 44 ng/mL). The decrease hepatic first-pass metabolism of NLT consecutive to end-stage renal disease and the renal impairment could explain the increased levels of the drug in plasma. Tmax before and after dialysis plates remain unchanged as healthy subjects (approximately 1h). With regard to dialysability, a high dialyzer extraction ratio averating 30 % was found with a low dialysis clearance of 58.70+/-17 mL/min. The amount removed by dialysis is only 1.27 mg. We concluded that hemodialysis has little effect on NLT blood levels, and consequently on drug pharmacokinetics, when the drug is delivered to dialyzed patients following oral route. Thus, dosage adjustement is not required in the presence of advanced dialysis-dependant renal failure. In patients with end-stage renal disease, hemodialysis does not result in clinically significant alterations in the disposition of NLT. Post-dialysis supplementation is not required. These data suggest that there is no pharmacokinetic basis for modification of the initial dosage, but in view of NLT plasma concentration levels in the patients, a clinician could determine whether dosage adjustment are necessary and, if so, make the required calculations accurately.

The beta-adrenoreceptor blocker labetalol has demonstrated important antioxidant properties in vitro that inhibit superoxide anion production during normal leukocyte oxidative metabolism. This study investigated the in vitro and ex vivo effects of labetalol on respiratory burst in rabbit neutrophils. The production of superoxide anions was examined in activated purified rabbit neutrophils after intravenous administration of labetalol (4.0 mg/kg of body weight). At a concentration up to 200 mg/L, labetalol did not demonstrate any cytotoxic effects on neutrophils, as determined by enzyme lactate dehydrogenase activity. In the cell-free system, labetalol demonstrated no significant activity, but in formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated rabbit neutrophils, labetalol demonstrated concentration-dependent antioxidant activity. The in vitro 50% inhibitory concentration (IC50) with the fMLP stimulus was 16.5+/-0.21 mg/L in the rabbit neutrophils and 13.2+/-0.16 mg/L in the human neutrophils. In the fMLP-stimulated rabbit polymorphonuclear leukocytes, labetalol demonstrated its peak inhibitory activity (47%) 3 hours after administration. The mechanism by which labetalol acts in the treatment of hypertension may occur from an interaction in the signaling pathway of protein kinase C activation. The antioxidant properties demonstrated in this mechanism contribute to the drug's antihypertensive action and thus, may reduce the risk of injuries inflicted by reactive oxygen species involved in the pathogenesis of hypertension.

On the basis of molecular modelling studies, five new compounds were synthesised and studied in an attempt to design new lead structures as selective COX-2 inhibitors.

Activated neutrophils which produce certain proteases, such as elastase and reactive oxygen species (ROS) are involved in oxidative stress and inflammation. In the present study, we have shown that nicardipine, a calcium channel blocker, affects the release of elastase and superoxide anion radicals (O2−) in vitro during human and rabbit neutrophil respiratory bursts. The drug inhibited the release of elastase and O2− by fMLP (N-formyl-methionylleucin-phenylalaninin), calcium ionophore (A23187) and PMA (phorbol-myristate-acetate)-stimulated human and rabbit neutrophils. Besides the release of elastase, strongly inhibited in the fMLP and A23187 stimulated systems, nicardipine affected elastase and O2− in a dose-dependent manner. The corresponding 50% inhibitory concentration (IC50) of nicardipine for elastase, released in PMA-stimulated human and rabbit neutrophils, was 15.95 ± 0.17 μM and 18.06 ± 0.08 μM, respectively, whereas for O2−, the IC50 of nicardipine in PMA, fMLP and A23187-stimulated human and rabbit neutrophils was 55.41 ± 0.09 μM and 58.43 ± 0.03 μM, 45.21 ± 0.13 μM and 37.19 ± 0.53 μM, 33.54 ± 0.09 μM and 30.54 ± 0.29, respectively. The mechanisms underlying the inhibition of elastase and superoxide anion radicals by nicardipine appear related to an inhibiting effect on the mobilisation of cytosolic calcium and on activation of protein kinase C (PKC). These antioxidant and anti-elastasic activities contribute to the properties of nicardipine, as positive side effects of its antihypertensive activity and may be useful to prevent inflammatory disorders (tissue damage, oxidative injury) involved in the pathogenesis of hypertension.

Background/Aims: The in vivo metabolic profile of a benzopyridooxathiazepine (BPT) derivative, a potent tubulin polymerization inhibitor with a promising in vitro activity, was investigated. Methods: The quantification of the BPT derivative and the identification of metabolites in the plasma of Wistar rats after i.p. and oral administration of 10 mg/kg were performed by the HPLC-mass spectrometry method. Results: Following a single i.p. dose of the BPT derivative, the plasma concentrations showed a biexponential decay (with a rapid decline) followed by a slow decay with a terminal half-life of 77.90 min. The area under the concentration-time curve from time 0 to infinity (AUC0-∞) was 18.90 µg/ml·min. After oral administration, the plasmatic concentrations reached a peak of 0.06 μg/ml at 35 min and then decayed with a half-life of 108 min. The AUC0-∞ was 10.25 µg/ml·min, representing 54.2% of the relative bioavailability. The compound was well distributed in the body, and its elimination seemed to be fast, regardless of the administration route. The major metabolic pathways were demethylation and hydroxylation reactions, both followed by conjugation with glucuronic acid. Conclusion: In rats, the BPT derivative is well distributed and undergoes extensive metabolism, leading to several metabolites. With promising in vitro activity and very good oral bioavailability, this compound seems to be an attractive candidate for further development as an anticancer agent.

In children undergoing total parenteral nutrition (PN), lipids provide a key source of calories preventing or correcting energy deficits and improving outcomes. However, some of these lipids may undergo oxidation leading to the formation of malondialdehyde (MDA), a cytotoxic byproduct found in these patients. This paper aims to describe a sensitive method for detecting MDA and discuss its role in certain diseases commonly found in children on regular PN. To quantify MDA levels in children benefitting from long-term cyclic PN, a reliable and sensitive high-performance liquid chromatographic method based on a 1-step derivatization/extraction procedure analysis with ultraviolet determination at 305 nm wavelength was achieved. In control children without PN, MDA levels were on average 3.30 ± 0.08 μM. However, in children nourished intravenously by fat emulsion for a long time, in which liver problems have been identified, the circulating concentrations of MDA ranged widely at both the start and the end of a session, 3- to 10-fold, respectively, in comparison with the levels measured in controls. This finding indicates that PN administrated long term raises plasma MDA levels, indicating chronic exposure and therefore a possible health risk, particularly liver damage. This preliminary study using a limited number of patients and controls showed that children undergoing long-term PN are strongly exposed to MDA, which must be considered as a potent toxic compound rather than a simple marker of lipid peroxidation.

The protein kinase C (PKC) is a serine/threonine kinase, consisting of different isoforms, implicated in numerous processes of signal transduction. To understand this enzyme well, different pharmacological tools were developed. To activate PKC specifically, phorbol esters were previously used but recent research has shown that these compounds are able to stimulate other proteins. Our model is the respiratory burst in the polymorphonuclear neutrophils. A decrease in the inflammatory process was measured using chelerythrine chloride. Action on PKC was proved by a binding study and by showing the absence of translocation of this enzyme from the cytoplasm to the plasmic membrane during stimulation.

The interest of polyphenolics as therapeutic agents against diseases involving radical damage is growing. The phenolic contents of the hulls and flour from the seeds of Fagopyrum esculentum (French variety 'La Harpe') (total phenols, flavonoids, total flavanols, oligomeric proanthocyanidins) are compared with the antioxidative effects of the extracts against reactive oxygen species: hydrogen peroxide, hypochlorous acid, superoxide anion. The higher efficiency of the flour extract can be related to its higher flavanolic content rather than to flavonoids which are predominant in the hull extract.

The present study aims at investigating the effect of bovine serum albumin (BSA) on the trial of oxidative-stress. The antioxidant effects of BSA were determined by human neutrophil granulocytes oxygen free radicals and their by-products (O − 2 , H 2 O 2 , HOCl) productions. BSA interacts with those reactive oxygen species (ROS) in a dose-dependent manner. The 50% inhibitory concentration (IC 50 ) of BSA estimated, after phorbol-12-myristate-13-acetate (PMA) stimulation were: 33.5 mg/ml for O − 2 , 6.5 mg/ml for H 2 O 2 , and 6.85 mg/ml for HOCl. When neutrophils were washed after pre-incubation with BSA, there was no significant decrease of ROS after stimulation of PMA (maximal: 15±1.2%). In the free cell experiments, IC 50 for H 2 O 2 and HOCl were 7.86 mg/ml and 0.67 mg/ml, respectively. The mechanism at which BSA acts may result from a simple chemical interaction with ROS rather than an intracellular mechanism by intervention in PMA oxidative metabolism. These antioxidant activities confer to BSA properties, which might be used to prevent damage inflicted by these ROS during inflammatory disorders.

Summary Background: Omeprazole has been marketed in France since 1989, for the healing of peptic ulcers, erosive reflux oesophagitis, and the Zollinger–Ellison syndrome. However, the drug has been associated with serious adverse reactions, including haemolytic anaemia and acute interstitial nephritis. More recently, an autoimmune syndrome induced by omeprazole has been described. Objective: We present here a clinical history and an in vitro test of cytotoxicity linking leukopenia to omeprazole. Results: A 37-year-old woman was hospitalized in the intensive care unit of our hospital with acute pulmonary insufficiency secondary to pneumonia. 72 h after starting omeprazole treatment, a decrease in leucocyte count was observed. The leukopenia was maximal on day 22: total white cell count was 2·1×109/l, and neutrophil count was less than 0·75×109/l. In order to find the cause of this leukopenia, an in vitro cytotoxicity test was performed. The test was positive only when patient neutrophils and patient serum were in the presence of omeprazole. This cytotoxicity seems to be complement-dependent, as in the presence of heated serum, the omeprazole toxic effect was substantially reduced. Conclusion: This case report suggests that the leukopenia was associated with omeprazole.

The clozapine-induced agranulocytosis could be due to the formation of a reactive intermediate formed in polymorphonuclear neutrophils and granulocyte precursors with the myeloperoxidase-hydrogen peroxide system. On the contrary, no case of agranulocytosis has been described for loxapine, an other neuroleptic drug with a very close structural analogy. We have compared the clozapine and loxapine interaction with the oxidative burst and particularly with this enzymatic complex. On the one hand, the assay of the oxidative species demonstrated a different impact for the two neuroleptics. The 50% inhibitory concentration was 92 microM for hydrogen peroxide and 40 microM for hypochlorous acid for loxapine. The loxapine target is located before the myeloperoxidase-hydrogen peroxide system in the oxidative stream, whereas clozapine diverts the chlorination pathway of the enzyme. On the other hand, the in vitro metabolism of drugs by the myeloperoxidase-hydrogen peroxide system has been investigated by mass spectrometry. Loxapine remains inert but clozapine undergoes the oxidation. The glutathione or ascorbate addition in the medium leads to a removal of the oxidation. Glutathione is able to trap the toxic intermediate and could avoid its formation.

Hospitals have at their disposal large databases that may be considered for reuse. The objective of this work is to evaluate the impact of a drug on a specific laboratory result by analyzing these data. This analysis first involves building a record of temporal patterns, including medical context, of drug prescriptions. Changes in outcome due to these patterns of drug prescription are assessed using short phases of the inpatient stay compared to monotonous changes in the laboratory result. To illustrate this technique, we investigated potassium chloride supplementation and its impact on kalemia. This method enables us to assess the impact of a drug (in its frequent context of prescription) on a laboratory result. This kind of analysis could play a role in post-marketing studies.

Management of vitamin K antagonists (VKA) is difficult, and overdoses can have dramatic hemorrhagic consequences. These works form part of a European computerized medical data processing project, which aims to develop IT tools for describing adverse drug events (ADEs). Materials and methods A tool enabling retrospective research of potential ADE cases was developed, using complex ADE detection rules taking into account chronological parameters: the ADE scorecards. The rules were applied on 14,748 medical records from a community hospital. We evaluated the predictive positive value of the rules related to INR elevation by an expert review of the detected cases. The severity of the clinical consequences was evaluated. Results 49 cases were detected, among which 11 cases were ADEs. The predictive positive value of the rules is 22.44%, mostly related to antibiotics and amiodarone introduction. The four cases of clinical damage related to a drug were properly designated by the rules. Discussion - Conclusion Our study shows the great potential of developing complex rules for the identification of adverse drug events in large medical databases.

The availability and compatibility of drugs from solutions infused via PVC infusion bags through PVC administration sets have been examined. No significant drug loss was observed during simulated infusions using PVC infusion bags and administration sets over time periods used in hospitals (cisplatin, 2 h; carboplatin, 1 h). The stability of carboplatin was studied in 5% dextrose. In 0.9% NaCl, we observed that carboplatin could be converted to cisplatin in the presence of chloride ions. With cisplatin, no significant difference was found between infusion solutions (5% dextrose or 0.9% NaCl). The stability of cisplatin (5% dextrose or 0.9% NaCl) and carboplatin (5% dextrose) was also studied in PVC bags after storage in the dark at room temperature. The results show that the drugs were stable over the 9-day storage period studied.

Adverse drug events (ADEs) are a public health is sue. Their detection usually relies on voluntary reporting or medical chart reviews. The objective of this paper is to automatically detect cases of ADEs by data mining. 115 447 complete past hospital stays are extracted from six French, Danish, and Bulgarian hospitals using a common data model including diagnoses, drug administrations, laboratory results, and free-text records. Different kinds of outcomes are traced, and supervised rule induction methods (decision trees and association rules) are used to discover ADE detection rules, with respect to time constraints. The rules are then filtered, validated, and reorganized by a committee of experts. The rules are described in a rule repository, and several statistics are automatically computed in every medical department, such as the confidence, relative risk, and median delay of outcome appearance. 236 validated ADE-detection rules are discovered; they enable to detect 27 different kinds of outcomes. The rules use a various number of conditions related to laboratory results, diseases, drug administration, and demographics. Some rules involve innovative conditions, such as drug discontinuations.

Medication related Computerized Decision Support System (CDSS) are known to have a positive impact on Adverse Drug Events (ADE) prevention but they face acceptance problems due to over alerting and usability issues. We present here a Human factors approach to the design of these Clinical Decision Support (CDS) functions and to their integration into different Electronic Health Record (EHR) / Computerized Physicians Order Entry (CPOE) systems, so that the resulting CDSS corresponds to the users needs and fits clinical workflows and cognitive processes. We used ethnographic observations completed with semi-structured interviews to analyse existing work situations and work processes. These were then described in detail using the SHEL (Software, Hardware, Environmentamp; Liveware) formalism, which enables a structured description of the work system and provides an appropriate classification of human errors potentially leading to ADEs. We then propose a Unified Modelling Language (UML) model supporting the characterization by the CDSS of the drug monitoring and clinical context of patients at risk of ADE. This model combines the status of the lab test orders on the one hand with the validity and normality of the lab results on the other hand. This makes the system able to catch the context of the monitoring of the drugs through their corresponding lab tests and lab results (e.g. kalemia for potassium) and also part of the context of the clinical status of the patient (actual lab values, but also diseases and other pathologies that are identified as potential causes of the ADE e.g. renal insufficiency and potassium). We show that making the system able to catch the monitoring and clinical contexts opens interesting opportunities for the design of the CDS information content and display mode. Implementing this model would allow the CDSS to take into account the actions already engaged by the healthcare team and to adapt the information delivered to the monitoring and clinical context, thus making the CDSS a partner to the clinicians, nurses and pharmacists.

In the field of the detection and prevention of preventable ADEs, several methods have been explored to decrease the rate of ADEs due to monitoring errors. This paper describes an innovative method that aims at improving patient safety by increasing ADEs' awareness of healthcare professionals. To this end, ADE-scorecards that provide healthcare professionals with retrospective data about ADEs' causes and rates have been developed. In order to evaluate the impact of this method on the ADE rate, in-field clinical tests have been set up. Data were collected by both qualitative (semi-structured interviews) and quantitative methods (log analysis and ADE rate calculation). Preliminary results reveal that ADE-scorecards are well-accepted by most of the healthcare professionals who intend to use them as discussion supports and/or learning tools. Thus, ADE-scorecards seem to be a relevant method to improve patient safety by increasing ADE-awareness of healthcare professionals.

Baclofen (β-p-chlorophenyl-GABA) is the reference selective agonist for the bicuculline-insensitive GABAB receptor. The search for new compounds having a high affinity for the GABAB receptor is very important to clarify structural requirements. In that sense, we report the synthesis, binding studies and X-ray determinations of various 3-heteroaromatic γ-aminobutyric acids. Biochemical investigations concerning their abilities to displace [3H] muscimol (GABAA) and [3H] baclofen (GABAB) in binding studies showed that the 4-amino-3-(5-methoxybenzo[b]furan-2-yl)butanoic acid 6a (IC50 = 22.16 μM/R (−) [3H] baclofen; IC50 = 5.6 μM/RS [3H] baclofen) has a specific affinity for the GABAB receptor. The crystal structure of compounds 6a and 6b associated with computer graphics molecular superimpositions allows some structural requirements for GABAB receptor ligands to be proposed.

On the basis of molecular modelling studies, five new compounds were synthesised and studied in an attempt to design new lead structures as selective COX-2 inhibitors.

The European project PSIP (Patient Safety through Intelligent Procedures in Medication) aims at semi-automatically identifying and preventing ADE. Automatically detected Adverse Drug Events have to be reviewed and validated by human experts. Existing methods usually have the experts review the cases and document their rating in a structured form. One of the limitations of these methods is their poor ability to analyze and clear the disagreements between the experts and the system. This paper presents an innovative Human Factors based method to support the review by clinicians and pharmacologists of these automatically detected ADE. We use think aloud methods and portable labs to track and record the experts reasoning and their reviewing cognitive procedures. We present preliminary results obtained with this method, which allows identifying the key data and information used to characterize the ADE. This method provides useful feedbacks allowing a continuous refinement and improvement of the automated detection system.

Objectives: The aim was to compare the in vitro effects of amoxicillin and ampicillin on the oxidative metabolism of polymorphonuclear neutrophils (PMNs). Methods: Superoxide radical anion production by PMNs, stimulated or not by various exogenous stimulants and in contact with increasing antibiotic concentrations, was measured using spectrophotometric methods. Results: Whereas a pro-oxidative action of amoxicillin on PMNs was obtained without exogenous stimulation or with opsonized zymosan (OZ), the O - 2 production by PMNs incubated with ampicillin did not increase significantly. Conclusions: This amoxicillin pro-oxidative effect could be due to the activation of the PMN NADPH oxidase, to its induction by a membrane effect or via the OZ pathway. It probably reinforces amoxicillin intrinsic bactericidal action and might partly explain the severe rashes sometimes occurring with amoxicillin treatment.

Summary Background: The use of extemporaneously prepared admixtures of drugs must be supported by documentation of their chemical stability. Objective: To assess the physical compatibility and the chemical stability of nefopam hydrochloride, a centrally acting non-opioid analgesic, when admixed with selected proton pump inhibitors (omeprazole, esomeprazole or pantoprazole), in bionolyte G5 injection for intravenous infusion. Method: Admixtures were assessed for periods of up to 72 h after storage at ambient temperature without protection from light and at +4 °C protected from light. A preparation was considered stable if the compounds of the mixture retained at least 90% of their original potency during the storage. Triplicate samples of nefopam and the selected proton pump inhibitors as well as the following mixtures (nefopam/omeprazole, nefopam/esomeprazole and nefopam/pantoprazole) were prepared in the concentrations required, in polypropylene bottles of bionolyte G5 injection. The physical compatibility was assessed by visual observation at each sampling interval. The chemical stability of the drugs was evaluated by high-performance liquid chromatography and by measurement of pH values. Results: During refrigerated storage, nefopam as well as the selected proton pump inhibitors, when prepared separately in bionolyte G5 injection maintained chemical stability for up to 7 days. At ambient storage conditions, the protons pump inhibitors maintained chemical stability for 24 h, but thereafter their concentrations decreased significantly at day 1. Nefopam maintained chemical stability for up to 72 h at +25 °C. Nefopam/omeprazole and nefopam/esomeprazole mixtures in bionolyte were physically incompatible with the mixtures exhibiting a black colour. They underwent rapid and extensive loss, making the combination unacceptable within minutes of mixing. However, the nefopam/pantoprazole mixture was compatible over the study period, but with a reduced duration of the stability. Conclusion: Within the limits defined above, nefopam and the selected proton pump inhibitors may be prepared separately in advance in bionolyte G5 injection. The nefopam/pantoprazole mixture was stable for a short period, while the nefopam/omeprazole and the nefopam/esomeprazole mixtures were incompatible and unusable, immediately upon admixture.

Baclofen (beta-(p-chlorophenyl)-GABA) is a selective agonist for the bicuculline-insensitive GABAB receptor. The search for new compounds that bind to the GABAB receptor is very important to clarify structural requirements. We report herein the synthesis and the binding studies of variously substituted 3-thienyl- and 3-furylaminobutyric acids. 4-Amino-3-(5-methyl-2-thienyl)butyric acid (5d) and 4-amino-3-(5-chloro-2-thienyl)butyric acid (5h) are potent and specific ligands for GABAB receptor. The IC50 values for the displacement of (R)-(-)-[3H]baclofen are 1.34 and 0.61 microM for 5d and 5h, respectively, as compared to 0.33 microM for baclofen.

Baclofen (β-p-chlorophenyl-GABA) is the reference selective agonist for the bicuculline-insensitive GABAB receptor. The search for new compounds having a high affinity for the GABAB receptor is very important to clarify structural requirements. In that sense, we report the synthesis, binding studies and X-ray determinations of various 3-heteroaromatic γ-aminobutyric acids. Biochemical investigations concerning their abilities to displace [3H] muscimol (GABAA) and [3H] baclofen (GABAB) in binding studies showed that the 4-amino-3-(5-methoxybenzo[b]furan-2-yl)butanoic acid 6a (IC50 = 22.16 μM/R (−) [3H] baclofen; IC50 = 5.6 μM/RS [3H] baclofen) has a specific affinity for the GABAB receptor. The crystal structure of compounds 6a and 6b associated with computer graphics molecular superimpositions allows some structural requirements for GABAB receptor ligands to be proposed.

A routine high-performance liquid chromatographic method for measuring midazolam in human serum has been developed. The sample preparation procedure consisted of simple liquid–liquid extraction with dichloromethane, followed by evaporation under nitrogen. The mobile phase used was a mixture of acetonitrile at 0.02 M and sodium acetate at pH 3.0 (80:20, v/v) and a flow-rate of 1.2 mL/min. The separation was performed on two cyanopropyl columns (150×4.6 mm). The detection was by UV absorption at 240 nm. A linear range from 10 to 1000 ng/mL and a quantification limit of 7.4 ng/mL of serum was reached. The mean intra-assay and inter-assay reproducibility from serum sample spiked with 100 ng/mL were 4.1 and 4.7%, respectively. The recoveries from serum sample spiked with 50, 100, 500 ng/mL were 85.46, 85.38 and 85.57%, respectively. This method was developed to allow pharmacokinetic study of midazolam in young patients in short surgical interventions. © 1997 by John Wiley & Sons, Ltd.

In an infection, polymorphonuclear neutrophils (PMN) become activated and they produce oxidizing compounds and elastase in the extracellular medium. Alpha-1-proteinase inhibitor (α1PI), a protease inhibitor which is inactivated by oxidants, is the main endogenous inhibitor of elastase helping to limit excessive elastase activity. This study evaluates the ability of a plant extract, Cola nitida nuts, to protect α1PI from inactivation by oxidizing compounds as reactive oxygen species. On the one hand, we have evaluated the direct effect of cola nut extract on neutrophil elastase, and on the H 2 O 2 and myeloperoxidase (MPO)–H 2 O 2 system via cell-free systems. Results showed that cola nut extract scavenges H 2 O 2 and therefore protects α1PI from HOCl which is produced from the MPO–H 2 O 2 system. Experiments also showed that cola extract has the capacity to limit elastase activity. On the other hand, we have worked on cellular systems including isolated PMN with the aim to study the effect of cola extract on PMN metabolism. PMN were stimulated with PMA, calcium ionophore or fMLP. Each stimulant possesses its own stimulation pathway. According to the inhibitory concentration obtained at 50%, the results on cellular systems led to the conclusion that cola extract can reduce elastase liberation from PMN. It can then be concluded that cola nut extract can protect α1PI from inactivation, and has an effect both on elastase liberation and elastase activity. The cola nut extract effect is rather biased towards a reduction in elastase release, thus limiting the injurious effects caused by this enzyme.

With a view to specifying structure-activity relationships we have synthesised a new series of analogues of the Rho-kinase inhibitor 1-(5-isoquinolinesulfonyl)-homopiperazine (Fasudil). The structural modifications concerned the isoquinolinyl heterocycle and the sulfonyl group which are the two main features of this lead compound. These analogues were evaluated on the actin cytoskeleton and on the enzymatic activity of Rho-kinase. Most of the chemical modifications result in a loss of activity showing that interactions of Fasudil with the catalytic domain of Rho-kinase seem to be particularly definite and sensitive to structural variations. The presence of an isoquinolinyl nitrogen and a basic amino group separated by a spacer bearing a sulfonamide function are of utmost importance. Only the tetra-hydroisoquinoline analogue 3 shows the same activity as Fasudil. Moreover, this compound is unable to inhibit PKC biological activity contrary to Fasudil. The loss of the aromatic property could increase the selectivity level in favour of compound 3.

We report the successful application to human venous blood of a novel method developed to purify rabbit polymorphonuclear neutrophils (PMNs) from whole blood. Human PMNs were separated from whole blood after sedimentation with dextran and histopaque density gradient centrifugation. 3.92 +/- 0.26 x 10(6) PMNs per ml of blood was harvested. The purity of the preparation was 92.00 +/- 1.10%. The PMNs isolated were capable of generating a high amount of reactive oxygen species (ROS) and elastase after stimulation with phorbol 12-myristate 13-acetate (PMA): 13.43 +/- 0.3 microM of O2-, 9.62 +/- 0.15 microM of H2O2 and 5.48 +/- 0.01 microM of elastase. This method gives equivalent yield and viability when applied to isolating human or rabbit PMNs, in comparison with standard methods used to isolate human PMNs. Our method could be usefully exploited for comparative studies of rabbit and human PMNs with a cellular model of inflammatory oxidative stress in which the monitoring parameters are ROS and elastase. Thus, the results of animal (rabbit) studies can be extended to human diseases.

Clozapine is an antipsychotic drug with few extra-pyramidal motor side-effects, used to treat schizophrenia which is resistant to classical neuroleptic therapy. This report shows that norclozapine but not clozapine-N-oxide has the same D2 receptor affinity as clozapine. Assay results suggest a bimodal distribution which may be explained by CYP1A2 polymorphism. Extensive metabolizers could produce other active metabolites, probably other hydroxy-clozapine derivatives.

A sensitive and specific high performance liquid chromatographic method (HPLC) was developed for measuring dopamine (DA) in human plasma samples. Dihydroxybenzylamine (DHBA) was employed as an internal standard. Following solvent extraction and separation on a C18 ion-pairing reversed phase column, the drug was detected by a fluorescence detector with excitation and emission wavelengths of 233 nm and 345 nm, respectively. This method was employed to evaluate dopamine dialysability in seven haemodialysed patients under continuous infusion of a positive inotropic agent. Results showed a high dialyser extraction ratio averaging 38.3%, but a low dialysis clearance of 67 ml/min. The fraction removed by dialysis is 2.5%. We concluded that haemodialysis has little effect on dopamine blood levels, and consequently on drug pharmacokinetics, when the drug is delivered to haemodialysed patients under intravenous infusion.

Trypanothione reductase (TR) is the primary enzyme responsible for the reduction of trypanothione, the analog of glutathione found in trypanosomatidae. We have discovered a series of diphenylsulfides which are potent inhibitors of TR and have no activity on mammalian glutathione reductase. These compounds are also active in vitro on various stages of the parasite. Although structurally related to phenothiazines, which are known to be TR inhibitors, these compounds are devoided of any neuroleptic activity, making them attractive leads to develop specific and non toxic anti-chagasic drugs.

The stability of miconazole in various diluents and polyvinyl chloride (PVC) containers was determined and the release of diethylhexyl phthalate (DEHP) from PVC bags into intravenous infusions of miconazole was measured. An injection formulation (80 ml) containing a 1% solution of miconazole with 11.5% of Cremophor EL was added to 250-ml PVC infusion bags containing 5% glucose injection or 0.9% sodium chloride injection, to give an initial nominal miconazole concentration of 2.42 mg ml-1, the mean concentration commonly used in clinical practice. Samples were assayed by stability-indicating high-performance liquid chromatography (HPLC) and the clarity was determined visually. Experiments were conducted to determine whether the stability and compatibility of miconazole would be compromised, and whether DEHP would be leached from PVC bags and PVC administration sets during storage and simulated infusion. There was no substantial loss of miconazole over 2 h simulated infusion irrespective of the diluent, and over 24 h storage irrespective of temperature (2-6 degrees C and 22-26 degrees C). All the solutions initially appeared slightly hazy. Leaching of DEHP was also detected during simulated delivery using PVC bags and PVC administration sets. There was a substantial difference between the amounts of DEHP released from PVC bags and from administration sets, and also between the amounts released in solutions stored in PVC bags at 2-6 degrees C and 22-26 degrees C over 24 h. At the dilution studied, miconazole was visually and chemically stable for up to 24 h. The storage of miconazole solutions in PVC bags seems to be limited by the leaching of DEHP rather than by degradation. To minimize patient exposure to DEHP, miconazole solutions should be infused immediately after their preparation in PVC bags.