Hydrophilic Interaction Liquid Chromatography-Electrospray Ionization Mass Spectrometry for Therapeutic Drug Monitoring of Metformin and Rosuvastatin in Human Plasma.

In this work a hydrophilic interaction liquid chromatography/positive ion electrospray mass spectrometric assay (HILIC/ESI-MS) has been developed and fully validated for the quantitation of metformin and rosuvastatin in human plasma. Sample preparation involved the use of 100 µL of human plasma, following protein precipitation and filtration. Metformin, rosuvastatin and 4-[2-(propylamino) ethyl] indoline 2 one hydrochloride (internal standard) were separated by using an X-Bridge-HILIC BEH analytical column (150.0 × 2.1 mm i.d., particle size 3.5 µm) with isocratic elution. A mobile phase consisting of 12% (v/v) 15 mM ammonium formate water solution in acetonitrile was used for the separation and pumped at a flow rate of 0.25 mL min−1. The linear range of the assay was 100 to 5000 ng mL−1 and 2 to 100 ng mL−1 for metformin and rosuvastatin, respectively. The current HILIC-ESI/MS method allows for the accurate and precise quantitation of metformin and rosuvastatin in human plasma with a simple sample preparation and a short a chromatographic run time (less than 15 min). Plasma samples from eight patients were further analysed proving the capability of the proposed method to support a wide range of clinical studies.

Hydrophilic interaction liquid chromatography-electrospray ionization mass spectrometry combined with fabric phase sorptive extraction for therapeutic drug monitoring of pioglitazone, repaglinide, and nateglinide in human plasma.

Polypharmacy in type 2 diabetes is an issue of major concern as the prescription of multiple medi-cations for the management of diabetes-associated comorbidities can lead to drug-to-drug interactions, which can pose serious risks to patients' health. Within this context, the development of bioanalytical methods for monitoring the therapeutic levels of antidiabetic drugs is notably useful to ensure patients' safety. In the present work, a liquid chromatography-mass spectrometry method for the quantitation of pioglitazone, repaglinide, and nateglinide in human plasma is described. Sample preparation was performed by fabric phase sorptive extraction (FPSE), and hydrophilic interaction liquid chromatography (HILIC) was implemented for the chromatographic separation of the analytes, using a ZIC®-cHILIC analytical column (150 × 2.1 mm, 3 µm) under isocratic elution. The mobile phase consisted of 10 mM ammonium formate aqueous solution (pH = 6.5)/ acetonitrile, 10/90 v/v, and was pumped at a flow rate of 0.2 mL min-1. Design of Experiments was used during the development of the sample preparation method to gain deeper insight into the effect of various experimental parameters on extraction efficiency, their potential interactions and to optimize the recovery rates of the analytes. The linearity of the assay was assessed over the ranges of 25 to 2000, 6.25 to 500, and 125 to 10000 ng mL-1 for pioglitazone, repaglinide, and nateglinide, respectively. The presented method was fully validated and can be used for the therapeutic monitoring of the targeted analytes in human plasma samples.

Implementation of the e-Bug Project in Greece.

The e-Bug pack and web site educational material has been translated and adapted to the Greek language and educational background, and implemented throughout Greece as a supplementary educational resource in elementary and junior high schools. Elementary and junior high school teachers in Greece have actively participated in the development of the e-Bug educational resource and supported the implementation of all e-Bug activities. Dissemination to all key national stakeholders has been undertaken, and endorsement has been obtained from educational and medical associations, societies and institutions. Independent evaluation has been carried out, as part of dissertation thesis projects, for postgraduate studies. The e-Bug educational resource provides all the essentials for the dissemination of good health behaviours in hygiene, monitoring the spread of infection and the prudent use of antibiotics, to the youth of this country. Its contribution is expected to be evident in the next adult generation.

International promotion of e-Bug, an infection prevention and control educational intervention: survey of partners across 14 countries.

BACKGROUND: Antimicrobial resistance (AMR) is a global threat to public health. e-Bug is an educational resource developed and promoted by a network of international partners. e-Bug seeks to reduce the spread of infection and use of antimicrobials in young people and the community, so helping to control AMR. This study aimed to explore how e-Bug is promoted by international partners and observe barriers to promotion, including the extent of education about antibiotics in schools. METHODS: A total of 29 e-Bug partners were invited to complete online questionnaires on (i) methods they use to promote e-Bug; and (ii) antibiotic topics covered in the national curriculum in their countries. RESULTS: Fourteen and 15 of 29 e-Bug partners across Europe and Palestine completed the promotional activities and curriculum questionnaires respectively. The most frequently reported methods of promotion included endorsement and collaboration with government and non-government sectors and involvement in national and global health awareness campaigns. Barriers to promotion included a lack of time and funding. The curriculum survey data showed variation in antibiotic education across Europe and Palestine, lack of antibiotic education for children under 11 years of age and little change in antibiotic topics included in the curriculum since 2006. CONCLUSIONS: Future and existing e-Bug partners should be encouraged to follow promotional activities reported in this paper, including ministry endorsement, educator training, international campaigns and youth programmes. We encourage all countries to increase antibiotic topics in the school curriculum across all ages.

A porous graphitized carbon LC-ESI/MS method for the quantitation of metronidazole and fluconazole in breast milk and human plasma.

Information on drug transfer into the breast milk is essential to protect the infant from undesirable adverse effects of maternal consumption of drugs and to allow effective pharmacological treatment of breastfeeding mothers. Metronidazole and fluconazole are two drugs frequently used in nursing women to treat various infections, thus questioning infant's safety due to drug exposure through breast milk. In this article a porous graphitized carbon LC/ESI-MS assay was developed for the quantitation of metronidazole and fluconazole in breast milk and human plasma. The assay was based on the use of 150 µL of biological samples, following acetonitrile precipitation of proteins and filtration that enabled injection into the LC/ESI-MS system. All analytes and the internal standard, ropinirole, were separated by using a porous graphitized carbon analytical column (150 × 2.1 mm i.d., particle size 5 µm) with isocratic elution. The mobile phase consists of 55% acetonitrile in water acidified with 0.1% concentrated formic acid and pumped at a flow rate of 0.25 mL min-1. The assay was linear over a concentration range of 0.1 to 15 µg mL-1 for all analytes in both biological samples. Intermediate precision was found to be <8.4% over the tested concentration ranges. A run time of <5 min for each sample made it possible to analyze a large number of biological samples per day. The method is the first reported application for the analysis of metronidazole and fluconazole in both breast milk and human plasma and it can be used to support a wide range of clinical studies.

A case study of polypharmacy management in nine European countries: Implications for change management and implementation.

BACKGROUND: Multimorbidity and its associated polypharmacy contribute to an increase in adverse drug events, hospitalizations, and healthcare spending. This study aimed to address: what exists regarding polypharmacy management in the European Union (EU); why programs were, or were not, developed; and, how identified initiatives were developed, implemented, and sustained. METHODS: Change management principles (Kotter) and normalization process theory (NPT) informed data collection and analysis. Nine case studies were conducted in eight EU countries: Germany (Lower Saxony), Greece, Italy (Campania), Poland, Portugal, Spain (Catalonia), Sweden (Uppsala), and the United Kingdom (Northern Ireland and Scotland). The workflow included a review of country/region specific polypharmacy policies, key informant interviews with stakeholders involved in policy development and implementation and, focus groups of clinicians and managers. Data were analyzed using thematic analysis of individual cases and framework analysis across cases. RESULTS: Polypharmacy initiatives were identified in five regions (Catalonia, Lower Saxony, Northern Ireland, Scotland, and Uppsala) and included all care settings. There was agreement, even in cases without initiatives, that polypharmacy is a significant issue to address. Common themes regarding the development and implementation of polypharmacy management initiatives were: locally adapted solutions, organizational culture supporting innovation and teamwork, adequate workforce training, multidisciplinary teams, changes in workflow, redefinition of roles and responsibilities of professionals, policies and legislation supporting the initiative, and data management and information and communication systems to assist development and implementation. Depending on the setting, these were considered either facilitators or barriers to implementation. CONCLUSION: Within the studied EU countries, polypharmacy management was not widely addressed. These results highlight the importance of change management and theory-based implementation strategies, and provide examples of polypharmacy management initiatives that can assist managers and policymakers in developing new programs or scaling up existing ones, particularly in places currently lacking such initiatives.

Quantification of three beta-lactam antibiotics in breast milk and human plasma by hydrophilic interaction liquid chromatography/positive-ion electrospray ionization mass spectrometry.

The use of cephalosporins during breast feeding raises several issues, including the risk of drug exposure through breast milk for the infant. In this paper, a hydrophilic interaction liquid chromatography/positive ion electrospray mass spectrometric assay (HILIC/ESI-MS) was developed for the quantitation of cefuroxime, cefoxitin, and cefazolin in breast milk and human plasma. The assay was based on the use of small sample size, 25 µL of biological samples, following acetonitrile precipitation of proteins and filtration that enabled injection into the HILIC/ESI-MS system. All analytes and the internal standard, alfuzosin, were separated by using a ZIC®-HILIC analytical column (150.0 × 2.1 mm i.d., particle size 3.5 µm, 200 Å) with isocratic elution. The mobile phase was composed of a 6% 12.5 mM ammonium acetate water solution in acetonitrile and pumped at a flow rate of 0.25 mL min-1 . The assay was linear over a concentration range of 0.2 to 5 µg mL-1 and 0.4 to 20 µg mL-1 for all the analytes in breast milk and in human plasma, respectively. Intermediate precision was found to be less than 4.2% over the tested concentration ranges. A run time of less than 12 min for each sample made it possible to analyze a large number of biological samples per day. The method is the first reported application of HILIC in the analysis of antibiotics in breast milk and human plasma and it can be used to support a wide range of clinical studies. Copyright © 2016 John Wiley & Sons, Ltd.

A modified Delphi study to determine the level of consensus across the European Union on the structures, processes and desired outcomes of the management of polypharmacy in older people.

BACKGROUND: Inappropriate use of multiple medicines (inappropriate polypharmacy) is a major challenge in older people with consequences of increased prevalence and severity of adverse drug reactions and interactions, and reduced medicines adherence. The aim of this study was to determine the levels of consensus amongst key stakeholders in the European Union (EU) in relation to aspects of the management of polypharmacy in older people. METHODS: Forty-six statements were developed on aspects of healthcare structures, processes and desired outcomes, with consensus defined at ≥ 80% agreement. Panel members were strategists (e.g. directors, leading clinicians and commissioners) from each of the 28 EU member states, with a target recruitment of five per member state. Three Delphi rounds were conducted via email, with panel members being provided with summative results and collated, anonymised comments at the commencement of Rounds 2 and 3. RESULTS: Ninety panel members were recruited (64.3% of target), with high participation levels throughout the three Delphi rounds (91.1%, 83.3%, 72.2%). During Round 1, consensus was obtained for 27/46 statements (58.7%), with an additional two statements in Round 2 and none in Round 3. Consensus was obtained for statements relating to: potential gain arising from polypharmacy management (3/4 statements); strategic development (7/7); change management (5/7) indicator measures (4/6); legislation (0/3); awareness raising (5/5); polypharmacy reviews (5/7); and EU vision (0/7). Analysis of free text comments indicated that the vision statements were too ambitious and not achievable by the specified timeframe of 2025. CONCLUSION: Consensus was obtained amongst key EU strategists around many aspects of polypharmacy management in older people. Notably, no consensus was achieved in relation to statements relating to the need to alter legislation in areas of healthcare delivery, remuneration and practitioner scope of practice. While the vision for the EU by 2025 was considered rather ambitious, there is great potential and clear opportunity to advance polypharmacy management throughout the EU and beyond.

Direct injection human plasma analysis for the quantification of antihypertensive drugs for therapeutic drug monitoring using hydrophilic interaction liquid chromatography/electrospray ionization mass spectrometry.

The concept of personalized medicine is related to the development of new sensitive, precise and accurate analytical methods for therapeutic drug monitoring. In this article a rapid, sensitive and specific method was developed for the quantification of aliskiren, losartan, valsartan and hydrochlorothiazide in human plasma. Sample preparation was performed by protein precipitation with acetonitrile followed by filtration. All analytes and the internal standard (tiamulin) were separated by hydrophilic interaction liquid chromatography using an X-Bridge-HILIC analytical column (150.0×2.1mm i.d., particle size 3.5µm) under isocratic elution. The mobile phase was composed of a 10% 5mM ammonium formate water solution pH 4.5, adjusted with formic acid, in acetonitrile and pumped at a flow rate of 0.25mLmin(-1). The assay was linear over the concentration range of 5-500ngmL(-1) for all the analytes. Intermediate precision was less than 5.2% over the tested concentration ranges. The method is the first reported application of HILIC in the analysis antihypertensives in human plasma. With a small sample size (50µL human plasma) and a run time less than 6.0min for each sample the method can be used to support a wide range of clinical studies and therapeutic drug monitoring.

Determination of nateglinide in human plasma by high-performance liquid chromatography with pre-column derivatization using a coumarin-type fluorescent reagent.

A sensitive and selective high-performance liquid chromatographic method has been developed and validated for the determination of nateglinide in human plasma. Nateglinide and the internal standard, undecylenic acid, were extracted from plasma by liquid-liquid extraction using a mixture of ethyl acetate-diethyl ether, 50:50 (v/v). Pre-column derivatization reaction was performed using a coumarin-type fluorescent reagent, N-(7-methoxy-4-methyl-2-oxo-2H-6-chromenyl)-2-bromoacetamide. The derivatization proceeded in acetone in the presence of potassium carbonate and catalyzed by 18-crown-6 ether. The fluorescent derivatives were separated under isocratic conditions on a Hypersil BDS-C8 analytical column (250.0 mm x 2.1 mm i.d., particle size 5 microm) with a mobile phase that consisted of 65% acetonitrile in water and pumped at a flow rate of 0.50 mL min(-1). The excitation and emission wavelengths were set at 345 and 435 nm, respectively. The assay was linear over a concentration range of 0.05-16.00 microg mL(-1) for nateglinide with a limit of quantitation of 0.05 microg mL(-1). Quality control samples (0.05, 4.50 and 16.00 microg mL(-1)) in five replicates from five different runs of analysis demonstrated intra-assay precision (%coefficient of variation <6.8%), inter-assay precision (%coefficient of variation <1.6%) and an overall accuracy (%relative error) less than -3.4%. The method can be used to quantify nateglinide in human plasma covering a variety of pharmacokinetic or bioequivalence studies.

Molecular analysis of ampicillin-resistant sporadic Salmonella typhi and Salmonella paratyphi B clinical isolates.

OBJECTIVE: To study the mechanisms of antibiotic resistance in Salmonella typhi and Salmonella paratyphi B clinical isolates, and the clonality of resistant strains. METHODS: Antibiotic susceptibility was tested by disk-agar diffusion. Conjugation experiments and plasmid analysis by agarose gel electrophoresis after EcoRI digestion were followed by hybridization to a digoxigenin-labeled TEM-type beta-lactamase probe. DNA fingerprints were obtained by pulsed-field gel electrophoresis of Xbal-digested chromosomal DNA. RESULTS: Three S. typhi isolates (7% of the isolates studied), of which one was ampicillin resistant and the other two multiresistant (ampicillin, chloramphenicol, tetracycline, sulfamethoxazole/trimethoprim and streptomycin), and two ampicillin-resistant S. paratyphi B isolates (25% of the isolates studied) were further evaluated. A 34-MDa conjugative plasmid, previously isolated from Salmonella enteritidis, conferred ampicillin resistance. A 100-MDa conjugative plasmid encoded resistance to chloramphenicol, tetracycline and sulfamethoxazole/trimethoprim, as well as ampicillin. Chromosomal fingerprinting revealed two distinct resistant strains for each serovar which were different from a matched set of sensitive S. typhi strains. CONCLUSIONS: Two conjugative, TEM-type beta-lactamase-encoding plasmids conferred ampicillin resistance to S. typhi and S. paratyphi B. The 34-MDa plasmid was identical to that previously characterized from S. enteritidis, while the 100-MDa plasmid also encoded resistance to chloramphenicol, tetracycline and sulfamethoxazole/trimethoprim. Resistant isolates did not belong to a single clone but rather represented distinct strains.