Axel Meierjohann
Åbo Akademi University
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Featured researches published by Axel Meierjohann.
Science of The Total Environment | 2012
Kevin V. Thomas; Lubertus Bijlsma; Sara Castiglioni; Adrian Covaci; Erik Emke; Roman Grabic; Félix Hernández; Sara Karolak; Barbara Kasprzyk-Hordern; Richard H. Lindberg; Miren López de Alda; Axel Meierjohann; Christoph Ort; Yolanda Picó; José Benito Quintana; Malcolm J. Reid; Joerg Rieckermann; Senka Terzić; Alexander L.N. van Nuijs; Pim de Voogt
The analysis of sewage for urinary biomarkers of illicit drugs is a promising and complementary approach for estimating the use of these substances in the general population. For the first time, this approach was simultaneously applied in 19 European cities, making it possible to directly compare illicit drug loads in Europe over a 1-week period. An inter-laboratory comparison study was performed to evaluate the analytical performance of the participating laboratories. Raw 24-hour composite sewage samples were collected from 19 European cities during a single week in March 2011 and analyzed for the urinary biomarkers of cocaine, amphetamine, ecstasy, methamphetamine and cannabis using in-house optimized and validated analytical methods. The load of each substance used in each city was back-calculated from the measured concentrations. The data show distinct temporal and spatial patterns in drug use across Europe. Cocaine use was higher in Western and Central Europe and lower in Northern and Eastern Europe. The extrapolated total daily use of cocaine in Europe during the study period was equivalent to 356 kg/day. High per capita ecstasy loads were observed in Dutch cities, as well as in Antwerp and London. In general, cocaine and ecstasy loads were significantly elevated during the weekend compared to weekdays. Per-capita loads of methamphetamine were highest in Helsinki and Turku, Oslo and Budweis, while the per capita loads of cannabis were similar throughout Europe. This study shows that a standardized analysis for illicit drug urinary biomarkers in sewage can be applied to estimate and compare the use of these substances at local and international scales. This approach has the potential to deliver important information on drug markets (supply indicator).
Addiction | 2014
Christoph Ort; Alexander L.N. van Nuijs; Jean-Daniel Berset; Lubertus Bijlsma; Sara Castiglioni; Adrian Covaci; Pim de Voogt; Erik Emke; Despo Fatta-Kassinos; Paul Griffiths; Félix Hernández; Iria González-Mariño; Roman Grabic; Barbara Kasprzyk-Hordern; Nicola Mastroianni; Axel Meierjohann; Thomas Nefau; Marcus Östman; Yolanda Picó; Inés Racamonde; Malcolm J. Reid; Jaroslav Slobodnik; Senka Terzić; Nikolaos S. Thomaidis; Kevin V. Thomas
Aims To perform wastewater analyses to assess spatial differences and temporal changes of illicit drug use in a large European population. Design Analyses of raw wastewater over a 1-week period in 2012 and 2013. Setting and Participants Catchment areas of wastewater treatment plants (WWTPs) across Europe, as follows: 2012: 25 WWTPs in 11 countries (23 cities, total population 11.50 million); 2013: 47 WWTPs in 21 countries (42 cities, total population 24.74 million). Measurements Excretion products of five illicit drugs (cocaine, amphetamine, ecstasy, methamphetamine, cannabis) were quantified in wastewater samples using methods based on liquid chromatography coupled to mass spectrometry. Findings Spatial differences were assessed and confirmed to vary greatly across European metropolitan areas. In general, results were in agreement with traditional surveillance data, where available. While temporal changes were substantial in individual cities and years (P ranging from insignificant to <10−3), overall means were relatively stable. The overall mean of methamphetamine was an exception (apparent decline in 2012), as it was influenced mainly by four cities. Conclusions Wastewater analysis performed across Europe provides complementary evidence on illicit drug consumption and generally concurs with traditional surveillance data. Wastewater analysis can measure total illicit drug use more quickly and regularly than is the current norm for national surveys, and creates estimates where such data does not exist.
Journal of Pharmaceutical Sciences | 2011
Niklas Sandler; Anni Määttänen; Petri Ihalainen; Leif Kronberg; Axel Meierjohann; Tapani Viitala; Jouko Peltonen
Medicines are most often oral solid dosage forms made into tablets or capsules, and there is little room for individualized doses. The drug substance and additives are processed through multiple production phases, including complex powder handling steps. In drug manufacturing, the control of the solid-state properties of active pharmaceutical ingredient (API) is essential and it offers opportunities for enhancement of drug delivery systems. In this context, inkjet printing technologies have emerged over the last decades in pharmaceutical and biological applications and offer solutions for controlling material and product characteristics with high precision. Here we report the concept of conventional inkjet printing technology to produce printable pharmaceutical dosage forms on porous substrates. Data are shown to demonstrate inkjet printing of APIs into paper substrates, and how the model drug substances (paracetamol, theophylline, and caffeine) are penetrating the porous substrates used. The method enables controlling not only the deposition but also the crystallization of the drug substances. We anticipate that the inkjet printing approach has immense potential in making sophisticated drug delivery systems by use of porous substrates in the future. For example, it may offer new perspectives for solving problems around poorly soluble drugs and dosing low-dose medicines accurately. Furthermore, with the advent of genetic mapping of humans, controlled inkjet dosing can bring solutions to fabricate on-demand individualized medicines for patients.
Environmental Science & Technology | 2013
Jenny-Maria Brozinski; Marja Lahti; Axel Meierjohann; Aimo Oikari; Leif Kronberg
Pharmaceutical residues are ubiquitous in rivers, lakes, and at coastal waters affected by discharges from municipal wastewater treatment plants. In this study, the presence of 17 different pharmaceuticals and six different phase I metabolites was determined in the bile of two wild fish species, bream (Abramis brama) and roach (Rutilus rutilus). The fish were caught from a lake that receives treated municipal wastewater via a small river. Prior to analyses, the bile content was enzymatically hydrolyzed to convert the glucuronide metabolites into the original pharmaceuticals or phase I metabolites. The solid phase extracts of hydrolyzates were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The anti-inflammatory drug naproxen could be detected in all the six bream and roach bile samples. Diclofenac was found in five of the bream and roach samples, while ibuprofen was detected in three bream and two roach samples. The observed bile concentrations of diclofenac, naproxen, and ibuprofen in bream ranged from 6 to 95 ng mL(-1), 6 to 32 ng mL(-1), and 16 to 34 ng mL(-1), respectively. The corresponding values in roach samples ranged from 44 to 148 ng mL(-1), 11 to 103 ng mL(-1) and 15 to 26 ng mL(-1), respectively. None of the other studied compounds could be detected. The study shows that pharmaceuticals originating from wastewater treatment plant effluents can be traced to the bile of wild bream and roach living in a lake where diclofenac, naproxen, and ibuprofen are present as pollutants.
Comparative Biochemistry and Physiology C-toxicology & Pharmacology | 2013
Thomas M. Lilley; Lasse Ruokolainen; Axel Meierjohann; Mirella Kanerva; Janina Stauffer; Veronika N. Laine; Janne Atosuo; Esa-Matti Lilius; Mikko Nikinmaa
The acute toxicity of organic tin compounds (OTCs) has been studied in detail. However, due to their complex nature, very little is known about species-specific methods of accumulation and consequences for food-webs. Chironomids, on which e.g. Daubentons bats feed, may act as vectors for the transport of organic tin compounds from aquatic to terrestrial ecosystems. Bats are prone to environmental toxins because of their longevity and their ecological role as top predators. Organic tin compounds are associated with increased formation of reactive oxygen species and associated oxidative damage as well as suppression of immune function. The present paper investigates whether the OTC, tributyltin (TBT) and its metabolite, dibutyltin (DBT), accumulate in natural populations of Daubentons bats and whether TBT-associated effects are seen in general body condition, redox balance, redox enzyme activities, associated oxidative damage of red blood cells and complement function. We discovered the concentration of bat fur DBT correlated with local marine sediment TBT concentrations. However, we did not find a correlation between the explanatory factors, bat fur DBT and marine sediment TBT concentrations, and several physiological and physical response variables apart from complement activity. Higher DBT concentrations resulted in weaker complement activity and thus a weaker immune response. Although the observed physiological effects in the present study were not strongly correlated to butyltin concentrations in fur or sediment, the result is unique for natural populations so far and raises interesting questions for future ecotoxicological studies.
Marine Pollution Bulletin | 2015
Raisa Turja; Kari K. Lehtonen; Axel Meierjohann; Jenny-Maria Brozinski; Emil Vahtera; Anna Soirinsuo; Alexander Sokolov; Pauline Snoeijs; Hélène Budzinski; Marie-Hélène Dévier; Laurent Peluhet; Jari-Pekka Pääkkönen; Markku Viitasalo; Leif Kronberg
Biological effects of wastewater treatment plant (WWTP) effluents were investigated in Baltic mussels (Mytilus trossulus) caged for one month 800m and 1100m from the WWTP discharge site and at a reference site 4km away. Significant antioxidant, genotoxic and lysosomal responses were observed close to the point of the WWTP discharge. Passive samplers (POCIS) attached to the cages indicated markedly higher water concentrations of various pharmaceuticals at the two most impacted sites. Modeling the dispersal of a hypothetical passive tracer compound from the WWTP discharge site revealed differing frequencies and timing of the exposure periods at different caging sites. The study demonstrated for the first time the effectiveness of the mussel caging approach in combination with passive samplers and the application of passive tracer modeling to examine the true exposure patterns at point source sites such as WWTP pipe discharges in the Baltic Sea.
Environmental Toxicology and Chemistry | 2012
Thomas M. Lilley; Axel Meierjohann; Lasse Ruokolainen; Jani Peltonen; Eero J. Vesterinen; Leif Kronberg; Mikko Nikinmaa
Due to their adsorptive behavior, organotin compounds (OTCs), such as tributyltin (TBT), are accumulated in aquatic sediments. They resist biodegradation and, despite a ban in 2008, are a potential source for future exposure. Sediment OTCs have mostly been measured from sites of known high concentrations such as ports, shipping lanes, and marine dredging waste sites. The possible flow of OTCs from marine to terrestrial ecosystems, however, has not been studied. In the present study, the authors assessed whether sediments in common reed beds (Phragmites australis) accumulate TBT and whether chironomid (Diptera: Chironomidae) communities developing in reed-bed sediments act as vectors in the transfer of TBT from aquatic to terrestrial ecosystems in the Airisto channel, Archipelago Sea. The authors also investigated whether distance from the only known source and depth and TBT concentration of the adjacent shipping lane affect reed-bed concentrations. Thirty-six sites along the Airisto channel were sampled at 2-km intervals with triplicate samples from reed beds and the adjacent shipping lane for sediment and seven reed-bed sites for chironomids, and these were analyzed with an solid phase extraction liquid chromatography tamdem mass spectrometry method. The closer to the source the sample site was, the higher the measured TBT concentrations were; and the deeper the shipping lane, the lower the concentration of TBT in reed-bed sediments. The chironomid TBT concentrations correlated with reed-bed sediment TBT concentrations and showed evidence of accumulation. Therefore, TBT may be transferred, through the food web, from aquatic to terrestrial ecosystems relatively close to a source through ecosystem boundaries, such as common reed beds, which are areas of high insect biomass production in the Archipelago Sea.
Rapid Communications in Mass Spectrometry | 2015
S. Rendon; Denys Mavrynsky; Axel Meierjohann; Armi Tiihonen; Kati Miettunen; Imran Asghar; Janne Halme; Leif Kronberg; Reko Leino
RATIONALE For commercialization of dye-sensitized solar cells (DSSCs), improvement of their long-term stability and efficiency is important. A key component in solar cells is the dye, its high purity and high stability. Here, methods for dye extraction and purification, and for determination of dye purity and dye degradation in DSSCs, were developed. METHODS A method was developed for extraction of the dye Z907 from intact solar cells using a water/ethanol mixture containing tetrabutylammonium hydroxide. The N719 dye synthesized in our laboratory was purified by gel filtration on Sephadex LH20. These dyes, along with the dyes N3 and RuL2 (NC)2, were analyzed using nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography coupled to an electrospray ionization quadrupole-time-of-flight mass analyzer (LC/MS) operating in negative ionization mode. RESULTS Purification of the synthesized N719 removed several impurities, including its undesired isomer with the thiocyanate ligand attached to ruthenium through sulfur instead of nitrogen. The dyes N719 and Z907 were successfully extracted from solar cells and together with N3 and RuL2 (NC)2 analyzed by LC/MS, although N719 isomerized almost immediately in basic aqueous solution. The [M-H](-1) ions were observed and the measured mass was within a ±6 ppm range from the exact mass. CONCLUSIONS LC/MS in combination with NMR spectroscopy was shown to provide useful information on dye structure, purity, and on the efficiency of the purification methods. These methods allow for further studies of solar cell dyes, which may provide the detailed information needed for the improvement and eventual commercialization of the solar cell technology.
Scandinavian Journal of Gastroenterology | 2017
Per M. Hellström; Panu Hendolin; Pertti Kaihovaara; Leif Kronberg; Axel Meierjohann; Anders Millerhovf; Lea I. Paloheimo; Heidi Sundelin; Kari Syrjänen; Dominic-Luc Webb; Mikko Salaspuro
Abstract Introduction: Helicobacter-induced atrophic gastritis with a hypochlorhydric milieu is a risk factor for gastric cancer. Microbes colonising acid-free stomach oxidise ethanol to acetaldehyde, a recognised group 1 carcinogen. Objective: To assess gastric production of acetaldehyde and its inert condensation product, non-toxic 2-methyl-1,3-thiazolidine-4-carboxylic acid (MTCA), after alcohol intake under treatment with slow-release L-cysteine or placebo. Methods: Seven patients with biopsy-confirmed atrophic gastritis, low serum pepsinogen and high gastrin-17 were studied in a cross-over single-blinded design. On separate days, patients randomly received 200 mg slow-release L-cysteine or placebo with intragastric instillation of 15% (0.3 g/kg) ethanol. After intake, gastric concentrations of ethanol, acetaldehyde, L-cysteine and MTCA were analysed. Results: Administration of L-cysteine increased MTCA (p < .0004) and decreased gastric acetaldehyde concentrations by 68% (p < .0001). The peak L-cysteine level was 7552 ± 2687 μmol/L at 40 min and peak MTCA level 196 ± 98 μmol/L at 80 min after intake. Gastric L-cysteine and MTCA concentrations were maintained for 3 h. The AUC for MTCA was 11-fold higher than acetaldehyde, indicating gastric first-pass metabolism of ethanol. With placebo, acetaldehyde remained elevated also at low ethanol concentrations representing ‘non-alcoholic’ beverages and food items. Conclusions: After gastric ethanol instillation, slow-release L-cysteine eliminates acetaldehyde to form inactive MTCA, which remains in gastric juice for up to 3 h. High acetaldehyde levels indicate a marked gastric first-pass metabolism of ethanol resulting in gastric accumulation of carcinogenic acetaldehyde. Local exposure of the gastric mucosa to acetaldehyde can be mitigated by slow-release L-cysteine capsules.
Gastroenterology | 2014
Per M. Hellström; Panu Hendolin; Pertti Kaihovaara; Leif Kronberg; Axel Meierjohann; Anders Millerhovf; Lea Paloheimo; Heidi Sundelin; Kari Syrjänen; Dominic-Luc Webb; Mikko Salaspuro
INTRODUCTION: Atrophic gastritis (AG) with concomitant acid-free or hypochlorhydric stomach and Helicobacter pylori infection are the two most important risk factors for gastric cancer. Gastric mucosa, many microbes colonizing acid-free stomach and H. pylori strains possess alcohol dehydrogenase activity capable of locally producing acetaldehyde (ACH) from ethanol. ACH produced from ethanol in oral cavity contributes to gastric ACH exposure via saliva. Limited capacity of mucosal cells and microbes to eliminate ACH, results in enhanced exposure of gastric mucosa to the carcinogenic actions of ACH. ACH associated with alcoholic beverages has been classified as carcinogenic (Group 1) to humans by IARC/ WHO. Capsule that slowly releases L-cysteine in the stomach converting ACH to inactive 4-methyltiazolidine-2-carboxylic acid (MTCA) has been recently implicated in prevention of gastric carcinogenesis among patients with AG. AIMS: To assess the production of ACH and MTCA in the stomach of AG patients following an exposure to 15% ethanol, with or without administration of L-cysteine. METHODS: Seven H.pylori positive patients, selected among 42 subjects with biopsy-confirmed AG, and fasting serum levels of pepsinogen (PG) I 10 pmol/L participated in the study. In a single-blinded fashion and on two separate days, patients were intubated with a nasogastric tube and exposed to15 % ethanol (0.3g/kg) and randomly 200 mg of L-cysteine or placebo. Gastric juice samples (5mL) were drawn every 20 min over a period of 4 hours and analyzed for pH and ACH-, ethanol-, L-cysteineand MTCA-concentrations. ACH and ethanol were analyzed by headspace gas chromatography and L-cysteineand MTCA-levels by liquid chromatography coupled to a triple-quadropole mass spectrometer. RESULTS: After intake of L-cysteine, free ACH levels in gastric juice decreased by a mean of 76% for 20 to 100min (p=0.0023, <0.0001, 0.0086, 0.0102 at 20-, 40-, 60and 100min, respectively). After placebo, peak ACH levels ranged from 11.5 to 52.7μM as compared to 1.5 to 20.2μM following L-cysteine. In gastric juice, the mean peak L-cysteine level was 11928μM at 40min and mean peak MTCA level 1824μM at 80min. At 80min after intake of L-cysteine MTCA level was 654-fold as compared with free ACH level in gastric juice. CONCLUSIONS: The first-pass metabolism of ethanol mediated by gastric mucosal cells and/or microbes results in a marked exposure of gastric mucosa to ACH. Without L-cysteine, ACH is distributed to local water phase and metabolized further to acetate by gastric mucosal low Km ALDH enzymes. As shown by high MTCA levels in gastric juice after ethanol and slow releasing L-cysteine, it can be calculated that up to 90 % of locally formed ACH is inactivated by Lcysteine, thus significantly reducing the exposure to carcinogenic acetaldehyde.