97 results on '"Zühlke S"'
Search Results
2. Long-Term Comparison of Trace Organics Removal Performances between Conventional and Membrane Activated Sludge Processes
- Author
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Zuehlke, S., Duennbier, U., Lesjean, B., Gnirss, R., and Buisson, H.
- Published
- 2006
3. Strike While the Iron is Hot: Land Trusts, Temperature Anomalies, and Agenda Setting for Local Open Space Referenda
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Zuhlke Samantha, Katz Juniper, and Brinkman Emani
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climate change ,nonprofit sector ,land trusts ,policy agenda ,land conservation ,Social pathology. Social and public welfare. Criminology ,HV1-9960 - Abstract
Despite substantial progress on understanding the influence of nonprofits in the policy process, the role of nonprofits in local agenda setting remains under-examined. Policy for land conservation is a key plank in climate change mitigation strategies making the role of land trusts in agenda setting for land conservation votes an important topic. Prior studies demonstrate that temperature anomalies increase the likelihood that climate change policy appears on state political agendas. We propose that land trusts play a critical role in facilitating this connection at the local level. Temperature anomalies create a policy window which contributes to the likelihood that conservation measures make it onto the political agenda. Combining temperature, land trust presence, and local conservation vote data from U.S. counties from 2009 to 2019, we find that both temperature anomalies and the presence of land trusts increase the probability that a land conservation measure will appear on the local political agenda. Further, we find that the effect of temperature anomalies on the probability of a vote taking place is conditional on land trust presence within the county. The findings advance existing nonprofit theory on ways in which nonprofits engage in the policy process and hint towards promising avenues of future research. The findings also provide practical evidence for practitioners and hold implications for how local policymakers can leverage existing organizations to implement climate change policy.
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- 2024
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4. Endophytic fungal strains of Fusarium solani, from Apodytes dimidiata E. Mey. ex Arn (Icacinaceae) produce camptothecin, 10-hydroxycamptothecin and 9-methoxycamptothecin
- Author
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Shweta, S., Zuehlke, S., Ramesha, B.T., Priti, V., Mohana Kumar, P., Ravikanth, G., Spiteller, M., Vasudeva, R., and Uma Shaanker, R.
- Published
- 2010
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5. Die intestinale Mikrobiota schützt vor cholestatischem Leberschaden durch FXR Aktivierung
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Schneider, KM, additional, Candels, LS, additional, Hov, JR, additional, Myllys, M, additional, Hassan, R, additional, Schneider, CV, additional, Wahlström, A, additional, Mohs, A, additional, Zühlke, S, additional, Liao, L, additional, Elfers, C, additional, Kilic, K, additional, Henricsson, M, additional, Molinaro, A, additional, Hatting, M, additional, Zaza, A, additional, Drasdo, D, additional, Frissen, M, additional, Gálvez, EJC, additional, Strowig, T, additional, Karlsen, TH, additional, Hengstler, JG, additional, Marschall, HU, additional, Ghallab, A, additional, and Trautwein, C, additional
- Published
- 2021
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6. Rhizosphere microbial communities associated to rose replant disease:links to plant growth and root metabolites
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Yim, B., Baumann, A., Grunewaldt-Stöcker, G., Liu, B., Beerhues, L., Zühlke, S., Sapp, M., Nesme, J., Sørensen, S. J., Smalla, K., Winkelmann, T., Yim, B., Baumann, A., Grunewaldt-Stöcker, G., Liu, B., Beerhues, L., Zühlke, S., Sapp, M., Nesme, J., Sørensen, S. J., Smalla, K., and Winkelmann, T.
- Abstract
Growth depression of Rosa plants at sites previously used to cultivate the same or closely related species is a typical symptom of rose replant disease (RRD). Currently, limited information is available on the causes and the etiology of RRD compared to apple replant disease (ARD). Thus, this study aimed at analyzing growth characteristics, root morphology, and root metabolites, as well as microbial communities in the rhizosphere of the susceptible rootstock Rosacorymbifera 'Laxa' grown in RRD-affected soil from two sites (Heidgraben and Sangerhausen), either untreated or disinfected by gamma -irradiation. In a greenhouse bioassay, plants developed significantly more biomass in the gamma -irradiated than in the untreated soils of both sites. Several plant metabolites detected in R. corymbifera 'Laxa' roots were site- and treatment-dependent. Although aloesin was recorded in significantly higher concentrations in untreated than in gamma -irradiated soils from Heidgraben, the concentrations of phenylalanine were significantly lower in roots from untreated soil of both sites. Rhizosphere microbial communities of 8-week-old plants were studied by sequencing of 16S rRNA, ITS, and cox gene fragments amplified from total community DNA. Supported by microscopic observations, sequences affiliated to the bacterial genus Streptomyces and the fungal genus Nectria were identified as potential causal agents of RRD in the soils investigated. The relative abundance of oomycetes belonging to the genus Pythiogeton showed a negative correlation to the growth of the plants. Overall, the RRD symptoms, the effects of soil treatments on the composition of the rhizosphere microbial community revealed striking similarities to findings related to ARD.
- Published
- 2020
7. Gibt es Risikofaktoren für eine Enukleation bei Patienten mit Endophthalmitis? Ergebnisse einer Übersicht von 13 Jahren Dauer
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Janknecht, P., Zühlke, S., and Hansen, L. L.
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- 2005
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8. The impact of variable temperatures on the redox conditions and the behaviour of pharmaceutical residues during artificial recharge
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Massmann, G., Greskowiak, J., Dünnbier, U., Zuehlke, S., Knappe, A., and Pekdeger, A.
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- 2006
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9. Quantitative detection of Fusarium pathogens and their mycotoxins in South African maize
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Boutigny, A.-L., Beukes, I., Small, I., Zühlke, S., Spiteller, M., Van Rensburg, B. J., Flett, B., and Viljoen, A.
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- 2012
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10. Did the spectrum of endophthalmitis change? A study comprising 13 years experience with operative therapy of endophthalmitis
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JANKNECHT, P., ZÜHLKE, S., and HANSEN, L. L.
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- 2006
11. Preparation, Extrusion and Characterization of Perovskite Catalysts
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Lintz, H.-G., primary and Zühlke, S., additional
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- 1998
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12. Apple replant disease: causes and mitigation strategies
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Winkelmann, T., Smalla, K., Amelung, W., Baab, G., Grunewaldt-Stöcker, G., Kanfra, X., Meyhöfer, R., Reim, S., Schmitz, M., Vetterlein, Doris, Wrede, A., Zühlke, S., Grunewaldt, J., Weiß, S., Schloter, M., Winkelmann, T., Smalla, K., Amelung, W., Baab, G., Grunewaldt-Stöcker, G., Kanfra, X., Meyhöfer, R., Reim, S., Schmitz, M., Vetterlein, Doris, Wrede, A., Zühlke, S., Grunewaldt, J., Weiß, S., and Schloter, M.
- Abstract
After replanting apple (Malus domestica Borkh.) on the same site severe growth suppressions, and a decline in yield and fruit quality are observed in all apple producing areas worldwide. The causes of this complex phenomenon, called apple replant disease (ARD), are only poorly understood up to now which is in part due to inconsistencies in terms and methodologies. Therefore we suggest the following definition for ARD: ARD describes a harmfully disturbed physiological and morphological reaction of apple plants to soils that faced alterations in their (micro-) biome due to the previous apple cultures. The underlying interactions likely have multiple causes that extend beyond common analytical tools in microbial ecology. They are influenced by soil properties, faunal vectors, and trophic cascades, with genotype-specific effects on plant secondary metabolism, particularly phytoalexin biosynthesis. Yet, emerging tools allow to unravel the soil and rhizosphere (micro-) biome, to characterize alterations of habitat quality, and to decipher the plant reactions. Thereby, deep insights into the reactions taking place at the root rhizosphere interface will be gained. Counteractions are suggested, taking into account that culture management should emphasize on improving soil microbial and faunal diversity as well as habitat quality rather than focus on soil disinfection.
- Published
- 2018
13. Novel insights into plant-endophyte communication: maytansine as an example
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Kusari, S, additional, Kusari, P, additional, Eckelmann, D, additional, Zühlke, S, additional, Kayser, O, additional, and Spiteller, M, additional
- Published
- 2016
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14. Antibiotics in groundwater under locations with high livestock density in Germany
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Balzer, F., primary, Zühlke, S., primary, and Hannappel, S., primary
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- 2016
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15. Uptake of Neonicotinoid Insecticides by Water-Foraging Honey Bees (Hymenoptera: Apidae) Through Guttation Fluid of Winter Oilseed Rape
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Reetz, J. E., primary, Schulz, W., additional, Seitz, W., additional, Spiteller, M., additional, Zühlke, S., additional, Armbruster, W., additional, and Wallner, K., additional
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- 2015
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16. Fate of a 14C-labeled nonylphenol isomer in a laboratory-scale membrane bioreactor
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Cirja, M., Zühlke, S., Ivashechkin, P., Schäffer, A., Corvini, P.F.X., and Publica
- Published
- 2006
17. Arbeitsmarktinstitutionen, Arbeitsmarktsegmentation und Erwerbsverläufe in der DDR
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Zühlke, S. and Goedicke, A.
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- 1999
18. Uptake of Neonicotinoid Insecticides by Water-Foraging Honey Bees (Hymenoptera: Apidae) Through Guttation Fluid of Winter Oilseed Rape.
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Reetz, J. E., Schulz, W., Seitz, W., Spiteller, M., Zühlke, S., Armbruster, W., and Wallner, K.
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NEONICOTINOIDS ,HONEYBEES ,FORAGING behavior ,RAPESEED ,INSECTICIDES - Abstract
The water-foraging activity of honey bees (Apis mellifera L.) on guttation fluid of seed-coated crops, such as winter oilseed rape (WOR; Brassica napus L.), has not yet been evaluated. We analyzed the uptake of active substances (a.s.) in guttation fluid by evaluating residues of honey-sac contents. In autumn, insecticide residues of up to 130 μg a.s. per liter were released in WOR guttation fluid; this concentration is noticeably lower than levels reported in guttation fluid of seed-coated maize. Until winter dormancy, the concentrations declined to <30 μg a.s. per liter. In spring, residues were linked to prewintered plants and declined steadily until flowering. The maximum release of residues in guttation fluid of seed-coated WOR occurs on the first leaves in autumn when the colonieś water demand decreases. For the first time, proof for the uptake of guttation fluid from seed-coated WOR by honey bees was provided by measuring residues in individual honey-sac contents. In total, 38 out of 204 samples (19%) showed residues of thiamethoxam at concentrations ranging from 0.3 to 0.95 μg per liter while the corresponding concentrations in guttation fluid of WOR varied between 3.6 to 12.9 μg thiamethoxam per liter. The amounts of thiamethoxam we found in the honey sacs of water-foraging honey bees were therefore below the thresholds in nectar and pollen that are considered to have negative effects on honey bees after chronic exposure. [ABSTRACT FROM AUTHOR]
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- 2016
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19. Quantitative detection of Fusarium pathogens and their mycotoxins in South African maize
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Boutigny, A.-L., primary, Beukes, I., additional, Small, I., additional, Zühlke, S., additional, Spiteller, M., additional, Van Rensburg, B. J., additional, Flett, B., additional, and Viljoen, A., additional
- Published
- 2011
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20. Sequestration of Manure-Applied Sulfadiazine Residues in Soils
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Förster, M., primary, Laabs, V., additional, Lamshöft, M., additional, Groeneweg, J., additional, Zühlke, S., additional, Spiteller, M., additional, Krauss, M., additional, Kaupenjohann, M., additional, and Amelung, W., additional
- Published
- 2009
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21. Degradation Pathway of Bisphenol A: Does ipso Substitution Apply to Phenols Containing a Quaternary α-Carbon Structure in the para Position?
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Kolvenbach, B., primary, Schlaich, N., additional, Raoui, Z., additional, Prell, J., additional, Zühlke, S., additional, Schäffer, A., additional, Guengerich, F. P., additional, and Corvini, P. F. X., additional
- Published
- 2007
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22. Draft Genome Sequence of the Bacterial Endophyte Priestia megaterium B1, Isolated from Roots of Apple ( Malus domestica ).
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Mahmoud FM, Kusari S, Kublik S, Benning S, Siani R, Zühlke S, Radl V, Mahnkopp-Dirks F, and Schloter M
- Abstract
Over the past years, a number of important traits supporting plant growth have been shown for different strains of Priestia megaterium (formerly known as Bacillus megaterium). Here, we report the draft genome sequence of the endophytic bacterial strain Priestia megaterium B1, which was isolated from surface-sterilized roots of apple plants., Competing Interests: The authors declare no conflict of interest.
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- 2023
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23. In vitro to in vivo acetaminophen hepatotoxicity extrapolation using classical schemes, pharmacodynamic models and a multiscale spatial-temporal liver twin.
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Dichamp J, Cellière G, Ghallab A, Hassan R, Boissier N, Hofmann U, Reinders J, Sezgin S, Zühlke S, Hengstler JG, and Drasdo D
- Abstract
In vitro to in vivo extrapolation represents a critical challenge in toxicology. In this paper we explore extrapolation strategies for acetaminophen (APAP) based on mechanistic models, comparing classical (CL) homogeneous compartment pharmacodynamic (PD) models and a spatial-temporal (ST), multiscale digital twin model resolving liver microarchitecture at cellular resolution. The models integrate consensus detoxification reactions in each individual hepatocyte. We study the consequences of the two model types on the extrapolation and show in which cases these models perform better than the classical extrapolation strategy that is based either on the maximal drug concentration (Cmax) or the area under the pharmacokinetic curve (AUC) of the drug blood concentration. We find that an CL-model based on a well-mixed blood compartment is sufficient to correctly predict the in vivo toxicity from in vitro data. However, the ST-model that integrates more experimental information requires a change of at least one parameter to obtain the same prediction, indicating that spatial compartmentalization may indeed be an important factor., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Dichamp, Cellière, Ghallab, Hassan, Boissier, Hofmann, Reinders, Sezgin, Zühlke, Hengstler and Drasdo.)
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- 2023
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24. A Silicon-Stereogenic Silanol - 18 O-Isotope Labeling and Stereogenic Probe Reveals Hidden Stereospecific Water Exchange Reaction.
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Langenohl F, Rösler J, Zühlke S, Kirchhoff JL, and Strohmann C
- Abstract
A silicon-stereogenic aminosilanol was isolated in excellent diastereomeric ratio and the absolute configuration was determined. The silanol is configurative and condensation stable in solution and shows stereoselective transformations with a clean stereospecific pathway in follow-up reactions, which leads to the isolation of a silicon-stereogenic zinc complex and siloxane compounds. Investigations with
18 O-labelled water and mass spectrometry analysis revealed an otherwise hidden exchange of oxygen atoms of silanol and water in solution that proceeds with retention of the configuration at the silicon center. This novel combination of a stereochemical probe and isotopic labeling in a silicon-stereogenic compound opens new analytic possibilities to study stereochemical courses of reactions with the aid of chiral silanols mechanistically., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)- Published
- 2023
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25. Pathogenic T Cells in Celiac Disease Change Phenotype on Gluten Challenge: Implications for T-Cell-Directed Therapies.
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Christophersen A, Zühlke S, Lund EG, Snir O, Dahal-Koirala S, Risnes LF, Jahnsen J, Lundin KEA, and Sollid LM
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- 2022
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26. A Low FODMAP Diet Reduces Symptoms in Treated Celiac Patients With Ongoing Symptoms-A Randomized Controlled Trial.
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van Megen F, Skodje GI, Lergenmuller S, Zühlke S, Aabakken L, Veierød MB, Henriksen C, and Lundin KEA
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- Adult, Diet, Diet, Gluten-Free, Disaccharides adverse effects, Fermentation, Humans, Monosaccharides adverse effects, Celiac Disease, Irritable Bowel Syndrome diagnosis
- Abstract
Background & Aims: A gluten-free diet usually leads to mucosal remission in celiac disease, but persistent symptoms are common. A low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet is an established treatment for irritable bowel syndrome (IBS). We have assessed the efficacy of a moderately low FODMAP diet on persistent symptoms in treated celiac patients., Methods: A randomized controlled trial was performed from 2018 to 2019 in 70 adults with biopsy-proven celiac disease. Inclusion criteria were as follows: persistent gastrointestinal symptoms defined by a Gastrointestinal Symptom Rating Scale (GSRS)-IBS version score of 30 or higher, gluten-free diet adherence for 12 months or longer, and serologic and mucosal remission. Participants were randomized to a low FODMAP-gluten-free diet (intervention) or usual gluten-free diet (control). The GSRS-IBS score was recorded at baseline and at weeks 1 to 4, and the Celiac Symptom Index at baseline and at week 4. Statistics included marginal models for repeated data and analyses of covariance., Results: We included 34 participants in the intervention group and 36 in the control group. Time development of GSRS-IBS total scores differed significantly between the groups (P
interaction < .001), evident after 1 week (mean difference in intervention vs control, -8.2; 95% CI, -11.5 to -5.0) and persisting through week 4 (mean difference in intervention vs control, -10.8; 95% CI, -14.8 to -6.8). Moreover, significantly lower scores were found for the dimensions of pain, bloating, diarrhea, and satiety (Pinteraction ≤ .04), but not constipation (Pinteraction = .43). FODMAP intake during the intervention was moderately low (mean, 8.1 g/d; 95% CI, 6.7-9.3 g/d). The Celiac Symptom Index was significantly lower in the intervention group at week 4 (mean difference, -5.8; 95% CI, -9.6 to -2.0)., Conclusions: A short-term moderately low FODMAP diet significantly reduced gastrointestinal symptoms and increased celiac disease-specific health, and should be considered for the management of persistent symptoms in celiac disease., Clinicaltrials: gov: NCT03678935., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2022
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27. Interruption of bile acid uptake by hepatocytes after acetaminophen overdose ameliorates hepatotoxicity.
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Ghallab A, Hassan R, Hofmann U, Friebel A, Hobloss Z, Brackhagen L, Begher-Tibbe B, Myllys M, Reinders J, Overbeck N, Sezgin S, Zühlke S, Seddek AL, Murad W, Brecklinghaus T, Kappenberg F, Rahnenführer J, González D, Goldring C, Copple IM, Marchan R, Longerich T, Vucur M, Luedde T, Urban S, Canbay A, Schreiter T, Trauner M, Akakpo JY, Olyaee M, Curry SC, Sowa JP, Jaeschke H, Hoehme S, and Hengstler JG
- Subjects
- Acetaminophen metabolism, Acetylcysteine pharmacology, Animals, Bile Acids and Salts metabolism, Hepatocytes metabolism, Humans, Liver metabolism, Mice, Mice, Inbred C57BL, Chemical and Drug Induced Liver Injury drug therapy, Chemical and Drug Induced Liver Injury metabolism, Chemical and Drug Induced Liver Injury prevention & control, Drug Overdose
- Abstract
Background & Aims: Acetaminophen (APAP) overdose remains a frequent cause of acute liver failure, which is generally accompanied by increased levels of serum bile acids (BAs). However, the pathophysiological role of BAs remains elusive. Herein, we investigated the role of BAs in APAP-induced hepatotoxicity., Methods: We performed intravital imaging to investigate BA transport in mice, quantified endogenous BA concentrations in the serum of mice and patients with APAP overdose, analyzed liver tissue and bile by mass spectrometry and MALDI-mass spectrometry imaging, assessed the integrity of the blood-bile barrier and the role of oxidative stress by immunostaining of tight junction proteins and intravital imaging of fluorescent markers, identified the intracellular cytotoxic concentrations of BAs, and performed interventions to block BA uptake from blood into hepatocytes., Results: Prior to the onset of cell death, APAP overdose causes massive oxidative stress in the pericentral lobular zone, which coincided with a breach of the blood-bile barrier. Consequently, BAs leak from the bile canaliculi into the sinusoidal blood, which is then followed by their uptake into hepatocytes via the basolateral membrane, their secretion into canaliculi and repeated cycling. This, what we termed 'futile cycling' of BAs, led to increased intracellular BA concentrations that were high enough to cause hepatocyte death. Importantly, however, the interruption of BA re-uptake by pharmacological NTCP blockage using Myrcludex B and Oatp knockout strongly reduced APAP-induced hepatotoxicity., Conclusions: APAP overdose induces a breach of the blood-bile barrier which leads to futile BA cycling that causes hepatocyte death. Prevention of BA cycling may represent a therapeutic option after APAP intoxication., Lay Summary: Only one drug, N-acetylcysteine, is approved for the treatment of acetaminophen overdose and it is only effective when given within ∼8 hours after ingestion. We identified a mechanism by which acetaminophen overdose causes an increase in bile acid concentrations (to above toxic thresholds) in hepatocytes. Blocking this mechanism prevented acetaminophen-induced hepatotoxicity in mice and evidence from patients suggests that this therapy may be effective for longer periods after ingestion compared to N-acetylcysteine., Competing Interests: Conflict of interest S.U. is holder and inventor on patents protecting Myrcludex B (Hepcludex/bulevirtide). All other authors declare that they have no conflict of interest. Please refer to the accompanying ICMJE disclosure forms for further details., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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28. Cytotoxic and genotoxic properties of artathomsonine, a new oxoberberine alkaloid from Artabotrys thomsonii (annonaceae).
- Author
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Nguemdjo Chimeze VW, Bankoglu EE, Zühlke S, Fannang VS, Eckelmann D, Chi Shirri J, Djuidje EN, Djama CM, Stopper H, and Wandji J
- Subjects
- DNA Damage, Molecular Structure, Alkaloids pharmacology, Annonaceae chemistry, Antineoplastic Agents
- Abstract
A phytochemical investigation of the liana of Artabotrys thomsonii led to the isolation of a new oxoberberine alkaloid, 2,10-dihydroxy-3,9-dimethoxy-8-oxo-protoberberine ( 7 ), along with six known compounds. Their chemical structures were elucidated by 1 D and 2 D NMR spectroscopic methods and HRESI-MS
n data analysis. Compounds 4 and 7 were selected for further in vitro investigations. In accordance with expectations from their chemical structures, compounds 7 and 4 showed a clear antioxidant activity in a cell-free assay, with compound 7 being 7-fold more active than 4 . Cytotoxicity, cytostatic and genotoxic effects only occurred at high micromolar concentrations of 50 µM or more. Compound 7 was slightly less effective than compound 4 . A low micromolar concentration of 10 µM did not cause any damaging cellular effects but showed potential for a protection against the micronucleus-inducing effect of reactive oxygen species hydrogen peroxide, although not to a significant extent.- Published
- 2022
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29. Pathogenic T Cells in Celiac Disease Change Phenotype on Gluten Challenge: Implications for T-Cell-Directed Therapies.
- Author
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Christophersen A, Zühlke S, Lund EG, Snir O, Dahal-Koirala S, Risnes LF, Jahnsen J, Lundin KEA, and Sollid LM
- Subjects
- ADP-ribosyl Cyclase 1 metabolism, Antigens, CD metabolism, CD4-Positive T-Lymphocytes cytology, CD4-Positive T-Lymphocytes metabolism, CD8-Positive T-Lymphocytes cytology, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes metabolism, Celiac Disease immunology, Glutens chemistry, HLA-DQ Antigens chemistry, HLA-DQ Antigens immunology, Humans, Immunotherapy, Integrin alpha Chains metabolism, Intraepithelial Lymphocytes cytology, Intraepithelial Lymphocytes immunology, Intraepithelial Lymphocytes metabolism, Phenotype, Protein Multimerization, CD4-Positive T-Lymphocytes immunology, Celiac Disease therapy, Glutens immunology
- Abstract
Gluten-specific CD4
+ T cells being drivers of celiac disease (CeD) are obvious targets for immunotherapy. Little is known about how cell markers harnessed for T-cell-directed therapy can change with time and upon activation in CeD and other autoimmune conditions. In-depth characterization of gluten-specific CD4+ T cells and CeD-associated (CD38+ and CD103+ ) CD8+ and γδ+ T cells in blood of treated CeD patients undergoing a 3 day gluten challenge is reported. The phenotypic profile of gluten-specific cells changes profoundly with gluten exposure and the cells adopt the profile of gluten-specific cells in untreated disease (CD147+ , CD70+ , programmed cell death protein 1 (PD-1)+ , inducible T-cell costimulator (ICOS)+ , CD28+ , CD95+ , CD38+ , and CD161+ ), yet with some markers being unique for day 6 cells (C-X-C chemokine receptor type 6 (CXCR6), CD132, and CD147) and with integrin α4β7, C-C motif chemokine receptor 9 (CCR9), and CXCR3 being expressed stably at baseline and day 6. Among gluten-specific CD4+ T cells, 52% are CXCR5+ at baseline, perhaps indicative of germinal-center reactions, while on day 6 all are CXCR5- . Strikingly, the phenotypic profile of gluten-specific CD4+ T cells on day 6 largely overlaps with that of CeD-associated (CD38+ and CD103+ ) CD8+ and γδ+ T cells. The antigen-induced shift in phenotype of CD4+ T cells being shared with other disease-associated T cells is relevant for development of T-cell-directed therapies., (© 2021 The Authors. Advanced Science published by Wiley-VCH GmbH.)- Published
- 2021
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30. Synergistic anti-inflammatory activities of a new flavone and other flavonoids from Tephrosia hildebrandtii vatke.
- Author
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Owor RO, Bedane KG, Openda YI, Zühlke S, Derese S, Ong'amo G, Ndakala A, and Spiteller M
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- Anti-Inflammatory Agents pharmacology, Cytokines, Flavonoids pharmacology, Humans, Leukocytes, Mononuclear, Tumor Necrosis Factor-alpha, Flavones pharmacology, Tephrosia
- Abstract
A new flavone, named hildeflavone ( 1 ) along with 7 other known flavonoids were isolated from the aerial parts of Tephrosia hildebrandtii Vatke. Their characterisation was based on NMR and MS data analysis. The anti-inflammatory properties of the crude extract, isolated compounds and combination of the compounds were investigated in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Treatment of the LPS-stimulated PBMCs with the isolated flavonoids at a concentration of 100 µM significantly reduced the production of interleukins (IL-1β, IL-2 and IL-6), interferon-gamma (IFN-γ), granulocyte macrophage-colony stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-α). It was also found that the combination of a flavone and flavanones exhibited remarkable synergistic anti-inflammatory effects on the production of the cytokines.[Figure: see text].
- Published
- 2021
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31. Gut microbiota depletion exacerbates cholestatic liver injury via loss of FXR signalling.
- Author
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Schneider KM, Candels LS, Hov JR, Myllys M, Hassan R, Schneider CV, Wahlström A, Mohs A, Zühlke S, Liao L, Elfers C, Kilic K, Henricsson M, Molinaro A, Hatting M, Zaza A, Drasdo D, Frissen M, Devlin AS, Gálvez EJC, Strowig T, Karlsen TH, Hengstler JG, Marschall HU, Ghallab A, and Trautwein C
- Subjects
- ATP Binding Cassette Transporter, Subfamily B genetics, Animals, Anti-Bacterial Agents administration & dosage, Cholangitis, Sclerosing metabolism, Cholangitis, Sclerosing pathology, Humans, Liver metabolism, Mice, Prognosis, ATP-Binding Cassette Sub-Family B Member 4, Bile Acids and Salts metabolism, Cholestasis metabolism, Gastrointestinal Microbiome, Receptors, Cytoplasmic and Nuclear metabolism, Signal Transduction
- Abstract
Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology for which there are no approved therapeutic options. Patients with PSC display changes in gut microbiota and in bile acid (BA) composition; however, the contribution of these alterations to disease pathogenesis remains controversial. Here we identify a role for microbiota-dependent changes in BA synthesis that modulates PSC pathophysiology. In a genetic mouse model of PSC, we show that loss of microbiota-mediated negative feedback control of BA synthesis results in increased hepatic BA concentrations, disruption of bile duct barrier function and, consequently, fatal liver injury. We further show that these changes are dependent on decreased BA signalling to the farnesoid X receptor, which modulates the activity of the rate-limiting enzyme in BA synthesis, CYP7A1. Moreover, patients with advanced stages of PSC show suppressed BA synthesis as measured by serum C4 levels, which is associated with poor disease prognosis. Our preclinical data highlight the microbiota-dependent dynamics of BA metabolism in cholestatic liver disease, which could be important for future therapies targeting BA and gut microbiome interactions, and identify C4 as a potential biomarker to functionally stratify patients with PSC and predict disease outcomes., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)
- Published
- 2021
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32. Impact of Nonylphenols and Polyhalogenated Compounds in Follicular Fluid on the Outcome of Intracytoplasmic Sperm Injection.
- Author
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Bullach A, Trapphoff T, Zühlke S, Spiteller M, and Dieterle S
- Subjects
- Adult, Female, Gas Chromatography-Mass Spectrometry, Humans, Pregnancy, Sperm Injections, Intracytoplasmic, Endocrine Disruptors analysis, Follicular Fluid chemistry, Phenols analysis
- Abstract
Endocrine-disrupting chemicals (EDCs) interfere with the mammalian hormone system and alter its endo- and paracrine regulation. The goal of the present study was to examine the presence of 14 EDCs, including the technical mixture of nonylphenols and Mirex, in human follicular fluid (FF) and to find a potential correlation between endocrine active substances and a possible impact on female fertility. Furthermore, potential sources of EDC exposition regarding patients' lifestyle and socioeconomic factors were investigated. Human FF was collected from a total of 210 women undergoing intracytoplasmic sperm injection-treatment cycles because of male subfertility. The presence of EDCs was analyzed using gas chromatography coupled with mass spectrometry. Thirteen of the 14 investigated EDCs were present in every FF sample; compounds with the highest concentrations in FF were nonylphenol and Mirex. Nearly all kinds of EDCs led to significantly reduced maturation and fertilization rate. No significant influence of EDC concentration on the clinical pregnancy rate was observed for neither of the analyzed EDCs. Patients who obtained their clothes and textiles at fashion discounters displayed a higher amount of EDCs in their FF. In contrast, patients' residential area, source of food products, and nicotine or caffeine consumed were not associated with EDC accumulation. Clinicaltrials.gov NCT01385605 (11 July 2011)., (© 2021. Society for Reproductive Investigation.)
- Published
- 2021
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33. Circulating CD103 + γδ and CD8 + T cells are clonally shared with tissue-resident intraepithelial lymphocytes in celiac disease.
- Author
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Risnes LF, Eggesbø LM, Zühlke S, Dahal-Koirala S, Neumann RS, Lundin KEA, Christophersen A, and Sollid LM
- Subjects
- Celiac Disease metabolism, Celiac Disease pathology, Clonal Evolution genetics, Glutens immunology, Humans, Immunohistochemistry, Immunophenotyping, Lymphocyte Count, Receptors, Antigen, T-Cell, alpha-beta immunology, T-Lymphocyte Subsets immunology, T-Lymphocyte Subsets metabolism, Antigens, CD metabolism, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes metabolism, Celiac Disease etiology, Clonal Evolution immunology, Integrin alpha Chains metabolism, Intraepithelial Lymphocytes immunology, Intraepithelial Lymphocytes metabolism, Receptors, Antigen, T-Cell, gamma-delta metabolism
- Abstract
Gut intraepithelial γδ and CD8
+ αβ T lymphocytes have been connected to celiac disease (CeD) pathogenesis. Based on the previous observation that activated (CD38+ ), gut-homing (CD103+ ) γδ and CD8+ αβ T cells increase in blood upon oral gluten challenge, we wanted to shed light on the pathogenic involvement of these T cells by examining the clonal relationship between cells of blood and gut during gluten exposure. Of 20 gluten-challenged CeD patients, 8 and 10 had increase in (CD38+ CD103+ ) γδ and CD8+ αβ T cells, respectively, while 16 had increase in gluten-specific CD4+ T cells. We obtained γδ and αβ TCR sequences of >2500 single cells from blood and gut of 5 patients, before and during challenge. We observed extensive sharing between blood and gut γδ and CD8+ αβ T-cell clonotypes even prior to gluten challenge. In subjects with challenge-induced surge of γδ and/or CD8+ αβ T cells, as larger populations of cells analyzed, we observed more expanded clonotypes and clonal sharing, yet no discernible TCR similarities between expanded and/or shared clonotypes. Thus, CD4+ T cells appear to drive expansion of clonally diverse γδ or CD8+ αβ T-cell clonotypes that may not be specific for the gluten antigen.- Published
- 2021
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34. Production of Siderophores by an Apple Root-Associated Streptomyces ciscaucasicus Strain GS2 Using Chemical and Biological OSMAC Approaches.
- Author
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Armin R, Zühlke S, Grunewaldt-Stöcker G, Mahnkopp-Dirks F, and Kusari S
- Subjects
- Chromatography, High Pressure Liquid methods, Malus metabolism, Plant Roots metabolism, Rhizosphere, Tandem Mass Spectrometry methods, Malus microbiology, Plant Roots microbiology, Siderophores metabolism, Streptomyces chemistry
- Abstract
Apple Replant Disease (ARD) is a significant problem in apple orchards that causes root tissue damage, stunted plant growth, and decline in fruit quality, size, and overall yield. Dysbiosis of apple root-associated microbiome and selective richness of Streptomyces species in the rhizosphere typically concurs root impairment associated with ARD. However, possible roles of Streptomyces secondary metabolites within these observations remain unstudied. Therefore, we employed the One Strain Many Compounds (OSMAC) approach coupled to high-performance liquid chromatography-high-resolution tandem mass spectrometry (HPLC-HRMS
n ) to evaluate the chemical ecology of an apple root-associated Streptomyces ciscaucasicus strain GS2, temporally over 14 days. The chemical OSMAC approach comprised cultivation media alterations using six different media compositions, which led to the biosynthesis of the iron-chelated siderophores, ferrioxamines. The biological OSMAC approach was concomitantly applied by dual-culture cultivation for microorganismal interactions with an endophytic Streptomyces pulveraceus strain ES16 and the pathogen Cylindrocarpon olidum and by comparison with the literature. We evaluated the dynamics of siderophore production under the combined influence of chemical and biological OSMAC triggers, temporally over 3, 7, and 14 days, to discern the strain's siderophore-mediated chemical ecology. We discuss our results based on the plausible chemical implications ofn and by comparison with the literature. We evaluated the dynamics of siderophore production under the combined influence of chemical and biological OSMAC triggers, temporally over 3, 7, and 14 days, to discern the strain's siderophore-mediated chemical ecology. We discuss our results based on the plausible chemical implications of S. ciscaucasicus strain GS2 in the rhizosphere.- Published
- 2021
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35. Isoflavones from the seedpods of Tephrosia vogelii and pyrazoisopongaflavone with anti-inflammatory effects.
- Author
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Owor RO, Derese S, Bedane KG, Zühlke S, Ndakala A, and Spiteller M
- Subjects
- Anti-Inflammatory Agents isolation & purification, Cells, Cultured, Granulocyte-Macrophage Colony-Stimulating Factor, Humans, Interferon-gamma, Interleukin-1beta, Isoflavones isolation & purification, Kenya, Molecular Structure, Phytochemicals isolation & purification, Phytochemicals pharmacology, Tumor Necrosis Factor-alpha, Anti-Inflammatory Agents pharmacology, Isoflavones pharmacology, Leukocytes, Mononuclear drug effects, Tephrosia chemistry
- Abstract
Phytochemical investigation of Tephrosia vogelii seedpods led to the isolation of twelve compounds: vogelisoflavone A (1), vogelisoflavone B (2), isopongaflavone (3), onogenin, luteolin, 4',7-dihydroxy-3'-methoxyflavanone, trans-p-hydroxycinnamic acid, tephrosin, 2-methoxygliricidol, dehydrorotenone, 6a,12a-dehydro-α-toxicarol and pinoresinol. Compounds 1 and 2 are reported as new natural products. Isopongaflavone (3) was structurally modified using hydrazine to pyrazoisopongaflavone (4). These compounds were characterized based on their NMR and HRESIMS data. Further, four compounds (1-4) were evaluated for their anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Treatment of the LPS-stimulated PBMCs with the compounds at a concentration of 100 μM suppressed the secretion of interleukin IL-1β interferon-gamma (IFN-γ), granulocyte macrophage-colony stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-α)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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36. Anti-inflammatory Flavanones and Flavones from Tephrosia linearis .
- Author
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Owor RO, Bedane KG, Zühlke S, Derese S, Ong'amo GO, Ndakala A, and Spiteller M
- Subjects
- Adult, Anti-Inflammatory Agents, Non-Steroidal chemistry, Cytokines drug effects, Cytokines metabolism, Female, Flavanones chemistry, Flavones chemistry, Humans, Ibuprofen pharmacology, Lipopolysaccharides pharmacology, Magnetic Resonance Spectroscopy, Male, Molecular Structure, Monocytes drug effects, Monocytes metabolism, Plant Components, Aerial chemistry, Plant Extracts pharmacology, Spectrometry, Mass, Electrospray Ionization, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Fabaceae chemistry, Flavanones pharmacology, Flavones pharmacology
- Abstract
Phytochemical analysis of a methanol-dichloromethane (1:1) extract of the aerial parts of Tephrosialinearis led to the isolation of 18 compounds. Seven of these, namely, lineaflavones A-D ( 1 - 4 ), 6-methoxygeraldone ( 5 ), 8″-acetylobovatin ( 6 ), and 5-hydroxy-7-methoxysaniculamin A ( 7 ) are new compounds. The compounds were characterized based on their NMR and HRMS
n data. The anti-inflammatory effects of the crude extract and isolated compounds were evaluated by measuring the levels of interleukins (IL-1β, IL-2, and IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). The crude extract inhibited the release of all cytokines except IL-1β, which slightly increased in comparison to the LPS control. All the tested compounds suppressed the production of IL-2, GM-CSF, and TNF-α. Whereas compounds 1 , 2 , 4 - 8 , 10 - 15 , 17 , and 18 decreased production of IL-6, compounds 1 , 2 , 4 , 7 , 10 , 13 - 15 , and 17 inhibited the release of IL-1β. It is worth noting that most of the compounds tested showed a superior reduction in cytokines release compared to the reference drug ibuprofen.- Published
- 2020
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37. CD38 expression on gluten-specific T cells is a robust marker of gluten re-exposure in coeliac disease.
- Author
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Zühlke S, Risnes LF, Dahal-Koirala S, Christophersen A, Sollid LM, and Lundin KE
- Subjects
- ADP-ribosyl Cyclase 1 genetics, Adult, Aged, Antibodies immunology, Biomarkers, Celiac Disease diagnosis, Cytokines metabolism, Female, Gene Expression, Glutens adverse effects, HLA Antigens genetics, HLA Antigens immunology, Humans, Immunoglobulin A immunology, Immunoglobulin G immunology, Male, Membrane Glycoproteins genetics, Middle Aged, Protein Binding, Young Adult, ADP-ribosyl Cyclase 1 metabolism, Celiac Disease etiology, Celiac Disease metabolism, Glutens immunology, Membrane Glycoproteins metabolism, T-Lymphocytes immunology, T-Lymphocytes metabolism
- Abstract
Background: Increasing efforts are being put into new treatment options for coeliac disease (CeD), a chronic disorder of the small intestine induced by gluten. Interleukin-2 (IL-2) and gluten-specific CD4 + T cells increase in the blood after four hours and six days, respectively, following a gluten challenge in CeD patients. These responses are unique to CeD and are not seen in controls. We aimed to evaluate different markers reflecting a recall response to gluten exposure that may be used to monitor therapy., Methods: CeD patients on a gluten-free diet underwent a one- ( n = 6) or three-day ( n = 7) oral gluten challenges. We collected blood samples at several time points between baseline and day 8, and monitored gluten-specific CD4 + T cells for their frequency and CD38 expression using HLA-DQ:gluten tetramers. We assessed the IL-2 concentration in plasma four hours after the first gluten intake., Results: The frequency of gut-homing, tetramer-binding, CD4 + effector memory T (tetramer + β7 + T
EM ) cells and the IL-2 concentration measured shortly after the first dose of gluten increased significantly after the one- and three-day gluten challenges, but large interindividual differences were exhibited. The frequency of tetramer + β7 + TEM plateaued between days 6 and 8 and was lower after the one-day challenge. We observed a consistent increase in CD38 expression on tetramer + β7 + TEM cells and did not find a significant difference between the one- and three-day challenges., Conclusions: The optimal time points for monitoring therapy response in CeD after a three-day oral gluten challenge is four hours for plasma IL-2 or six to eight days for the frequency of tetramer + β7 + TEM cells, but both these parameters involved large interindividual differences. In contrast, CD38 expression on tetramer + β7 + TEM cells increased uniformly and irrespectively of the length of gluten challenge, suggesting that this parameter is more suited for monitoring drug efficacy in clinical trials for CeD., (© Author(s) 2019.)- Published
- 2019
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38. Distinct phenotype of CD4 + T cells driving celiac disease identified in multiple autoimmune conditions.
- Author
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Christophersen A, Lund EG, Snir O, Solà E, Kanduri C, Dahal-Koirala S, Zühlke S, Molberg Ø, Utz PJ, Rohani-Pichavant M, Simard JF, Dekker CL, Lundin KEA, Sollid LM, and Davis MM
- Subjects
- Celiac Disease classification, Glutens immunology, HLA-DQ Antigens immunology, Humans, Immunophenotyping, Intestines immunology, Lupus Erythematosus, Systemic immunology, Scleroderma, Systemic immunology, T-Lymphocyte Subsets classification, T-Lymphocyte Subsets immunology, Autoimmune Diseases immunology, CD4-Positive T-Lymphocytes immunology, Celiac Disease immunology
- Abstract
Combining HLA-DQ-gluten tetramers with mass cytometry and RNA sequencing analysis, we find that gluten-specific CD4
+ T cells in the blood and intestines of patients with celiac disease display a surprisingly rare phenotype. Cells with this phenotype are also elevated in patients with systemic sclerosis and systemic lupus erythematosus, suggesting a way to characterize CD4+ T cells specific for disease-driving antigens in multiple autoimmune conditions.- Published
- 2019
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39. Apple Replant Disease: Causes and Mitigation Strategies.
- Author
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Winkelmann T, Smalla K, Amelung W, Baab G, Grunewaldt-Stöcker G, Kanfra X, Meyhöfer R, Reim S, Schmitz M, Vetterlein D, Wrede A, Zühlke S, Grunewaldt J, Weiß S, and Schloter M
- Subjects
- Bacteria, Fungi, Host-Pathogen Interactions, Microbial Interactions, Microbiota, Plant Roots microbiology, Plant Roots physiology, Soil Microbiology, Disease Susceptibility, Malus physiology, Plant Diseases microbiology
- Abstract
After replanting apple (Malus domestica Borkh.) on the same site severe growth suppressions, and a decline in yield and fruit quality are observed in all apple producing areas worldwide. The causes of this complex phenomenon, called apple replant disease (ARD), are only poorly understood up to now which is in part due to inconsistencies in terms and methodologies. Therefore we suggest the following definition for ARD: ARD describes a harmfully disturbed physiological and morphological reaction of apple plants to soils that faced alterations in their (micro-) biome due to the previous apple cultures. The underlying interactions likely have multiple causes that extend beyond common analytical tools in microbial ecology. They are influenced by soil properties, faunal vectors, and trophic cascades, with genotype-specific effects on plant secondary metabolism, particularly phytoalexin biosynthesis. Yet, emerging tools allow to unravel the soil and rhizosphere (micro-) biome, to characterize alterations of habitat quality, and to decipher the plant reactions. Thereby, deep insights into the reactions taking place at the root rhizosphere interface will be gained. Counteractions are suggested, taking into account that culture management should emphasize on improving soil microbial and faunal diversity as well as habitat quality rather than focus on soil disinfection.
- Published
- 2019
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40. Spatio-temporal visualization of the distribution of acetaminophen as well as its metabolites and adducts in mouse livers by MALDI MSI.
- Author
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Sezgin S, Hassan R, Zühlke S, Kuepfer L, Hengstler JG, Spiteller M, and Ghallab A
- Subjects
- Acetaminophen administration & dosage, Acetaminophen analogs & derivatives, Acetaminophen analysis, Animals, Benzoquinones metabolism, Cytochrome P-450 CYP2E1 metabolism, Dose-Response Relationship, Drug, Glutathione metabolism, Imines metabolism, Liver metabolism, Male, Mice, Inbred C57BL, Spatio-Temporal Analysis, Acetaminophen adverse effects, Acetaminophen pharmacokinetics, Liver drug effects, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
- Abstract
Acetaminophen (APAP) is one of the most intensively studied compounds that causes hepatotoxicity in the pericentral region of the liver lobules. However, spatio-temporal information on the distribution of APAP, its metabolites and GSH adducts in the liver tissue is not yet available. Here, we addressed the question, whether APAP-GSH adducts and GSH depletion show a zonated pattern and whether the distribution of APAP and its glucuronide as well as sulfate conjugates in liver lobules are zonated. For this purpose, a matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) technique was established, where the MSI images were superimposed onto CYP2E1 immunostained tissue. A time-dependent analysis (5, 15, 30, 60, 120, 240, 480 min) after intraperitoneal administration of 300 mg/kg APAP and a dose-dependent analysis (56 up to 500 mg APAP/kg) at 30 min were performed. The results demonstrate that the MALDI MSI technique allows the assignment of compounds and their metabolites to specific lobular zones. APAP-GSH adducts and GSH depletion occurred predominantly in the CYP2E1-positive zone of the liver, although GSH also decreased in the periportal region. In contrast, the parent compound, APAP sulfate and APAP glucuronide did not show a zonated pattern and tissue concentrations showed a similar time course as the corresponding analyses were performed with blood from the portal and liver veins. In conclusion, the present study is in agreement with the concept that pericentral CYPs form NAPQI that in the same cell binds to and depletes GSH but a lower level of GSH adducts is also observed in the periportal region. The results also provide further evidence of the recently published concept of 'aggravated loss of clearance capacity' according to which also liver tissue that survives intoxication may transiently show decreased metabolic capacity.
- Published
- 2018
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41. seco-Tiaminic acids B and C: Identification of two novel 3,4-seco-tirucallane triterpenoids isolated from the root of Entandrophragma congoënse (Meliaceae).
- Author
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Happi GM, Talontsi FM, Laatsch H, Zühlke S, Ngadjui BT, Spiteller M, and Kouam SF
- Subjects
- Animals, Antimalarials isolation & purification, Cell Line, Molecular Structure, Plant Roots chemistry, Plasmodium falciparum drug effects, Rats, Triterpenes isolation & purification, Antimalarials chemistry, Meliaceae chemistry, Triterpenes chemistry
- Abstract
Chemical investigation of the roots of Entandrophragma congoënse (Meliaceae) led to the isolation of two new 3,4-seco-tirucallane triterpenes, namely seco-tiaminic acids B and C (1 and 2) together with nine known compounds: 3,4-secotirucalla-21-formyl-23-oxo-4(28),7,24-trien-3-oic acid (3), methyl angolensate (4), molucensin N (5), molucensin O (6), piscidinol A (7), 7α,20(S)-dihydroxy-4,24(28)-ergostadien-3-one (8), 24-methylene-cholest-5-en-3β,7α-diol (9), entilin A (10), and entilin B (11). Their structures were determined using extensive spectroscopic methods including 1D and 2D NMR, HRMS, and CD analyses; new results were compared to existing data in the literature. The two newly identified seco-tiaminic acids showed moderate antiplasmodial and cytotoxic activities against a chloroquine-sensitive strain of the malaria parasite (Plasmodium falciparum NF54) and were cytotoxic toward an L6 rat skeletal myoblast cell line, respectively., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2018
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42. Synthetic Origin of Tramadol in the Environment.
- Author
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Kusari S, Tatsimo SJ, Zühlke S, and Spiteller M
- Subjects
- Environmental Pollutants chemistry, Ghana, Plant Roots chemistry, Rubiaceae chemistry, Soil chemistry, Tramadol chemistry, Environmental Pollutants analysis, Environmental Pollutants chemical synthesis, Tramadol analysis, Tramadol chemical synthesis
- Abstract
The presence of tramadol in roots of Sarcocephalus latifolius trees in Northern Cameroon was recently attributed to point contamination with the synthetic compound. The synthetic origin of tramadol in the environment has now been unambiguously confirmed. Tramadol samples isolated from tramadol pills bought at a street market in downtown Maroua and highly contaminated soil at Houdouvou were analyzed by high-precision (14)C measurements by accelerator mass spectrometry ((14)C AMS): Tramadol from the pills did not contain any radiocarbon, thus indicating that it had been synthesized from (14)C-free petroleum-derived precursors. Crucially, tramadol isolated from the soil was also radiocarbon-free. As all biosynthetic plant compounds must contain radiocarbon levels close to that of the contemporary environment, these results thus confirm that tramadol isolated from the soil cannot be plant-derived. Analyses of S. latifolius seeds, in vitro grown plants, plants from different origins, and stable-isotope labeling experiments further confirmed that synthetic tramadol contaminates the environment., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2016
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43. Prenylated 2-arylbenzofuran derivatives with potent antioxidant properties from Chlorophora regia (Moraceae).
- Author
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Kyekyeku JO, Kusari S, Adosraku RK, Zühlke S, and Spiteller M
- Subjects
- Ghana, Medicine, African Traditional, Molecular Structure, Prenylation, Benzofurans chemistry, Free Radical Scavengers chemistry, Moraceae chemistry, Plant Bark chemistry, Plant Extracts chemistry
- Abstract
Extracts of Chlorophora regia are frequently used in Ghana in traditional medicine. There is, however, no reported data on the chemical composition of the plant. Comprehensive phytochemical investigation of the stem bark of C. regia resulted in the isolation of three new prenylated 2-arylbenzofuran derivatives, regiafuran A-C (1-3), and one new prenylated flavonol (4), together with fifteen known compounds (5-19). Their structures were elucidated by combined spectroscopic analysis of their NMR and HRESI-MS(n) data. Compounds 1, 2, 5, 9 and 15 exhibited remarkable free radical scavenging properties with IC50 values of 1.9 μg/ml, 2.4 μg/ml, 2.2 μg/ml, 2.1 μg/ml and 1.8 μg/ml, respectively, compared to the standard trolox (IC50 1.1 μg/ml). The isolated compounds did not, however, show any anti-inflammatory potential when tested using a PGE2 (prostaglandin E2) competitive enzyme immunoassay., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
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44. Antiplasmodial and Cytotoxic Triterpenoids from the Bark of the Cameroonian Medicinal Plant Entandrophragma congoënse.
- Author
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Happi GM, Kouam SF, Talontsi FM, Lamshöft M, Zühlke S, Bauer JO, Strohmann C, and Spiteller M
- Subjects
- Animals, Antimalarials chemistry, Cameroon, Chloroquine pharmacology, Disease Resistance drug effects, Erythrocytes drug effects, Molecular Structure, Muscle, Skeletal drug effects, Nuclear Magnetic Resonance, Biomolecular, Parasitic Sensitivity Tests, Plant Bark chemistry, Plant Stems chemistry, Plasmodium falciparum drug effects, Rats, Triterpenes chemistry, Antimalarials isolation & purification, Antimalarials pharmacology, Meliaceae chemistry, Plants, Medicinal chemistry, Triterpenes isolation & purification, Triterpenes pharmacology
- Abstract
Eight new triterpenoids, prototiamins A-G (1-6, 9) and seco-tiaminic acid A (10), were isolated along with four known compounds from the bark of Entandrophragma congoënse. Their structures were elucidated by means of HRMS and different NMR techniques and chemical transformations. Assignments of relative and absolute configurations for the new compounds were achieved using NOESY experiments and by chemical modification including the advanced Mosher's method. Additionally, the structure and relative configuration of compound 3 were confirmed by single-crystal X-ray diffraction analysis. Compounds 1, 3, and 5 displayed significant in vitro antiplasmodial activity against the erythrocytic stages of chloroquine-sensitive Plasmodium falciparum strain NF54. Prototiamin C (3) was the most potent of the compounds isolated, with an IC50 value of 0.44 μM. All compounds tested showed low cytotoxicity for the L6 rat skeletal myoblast cell line.
- Published
- 2015
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45. Minor secondary metabolites from the bark of Entandrophragma congoënse (Meliaceae).
- Author
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Happi GM, Kouam SF, Talontsi FM, Zühlke S, Lamshöft M, and Spiteller M
- Subjects
- Animals, Antimalarials chemistry, Antimalarials isolation & purification, Cell Line, Molecular Structure, Plasmodium falciparum drug effects, Rats, Triterpenes isolation & purification, Meliaceae chemistry, Plant Bark chemistry, Triterpenes chemistry
- Abstract
Two new tirucallane-type triterpenoids were isolated from the bark of Entandrophragma congoënse (Meliaceae) along with five known compounds gladoral A, bipendensin, 4-hydroxymethyl-3,5-dimethyldihydrofuran-2(3H)-one, scopoletin and 5,7-dimethoxy-6-hydroxycoumarin. Their structures were elucidated by means of spectroscopic analyses including 1D and 2D-NMR spectroscopy, high resolution mass spectrometric data as well as the comparison of data with those reported in the literature. The tested compounds (1-4) displayed moderated antiplasmodial activity against erythrocytic stages of chloroquine-resistant Plasmodium falciparum strain NF54 and low cytotoxicity on L6 cell lines. All the isolated compounds are reported for the first time from the genus Entandrophragma., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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46. Endophytes are hidden producers of maytansine in Putterlickia roots.
- Author
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Kusari S, Lamshöft M, Kusari P, Gottfried S, Zühlke S, Louven K, Hentschel U, Kayser O, and Spiteller M
- Subjects
- Aminobenzoates metabolism, Celastraceae metabolism, Celastraceae microbiology, Chromatography, High Pressure Liquid, Endophytes metabolism, Hydroxybenzoates metabolism, Maytansine chemistry, Maytansine pharmacology, Molecular Structure, Plant Roots metabolism, Plant Roots microbiology, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Endophytes chemistry, Hydro-Lyases metabolism, Maytansine isolation & purification
- Abstract
Several recent studies have lent evidence to the fact that certain so-called plant metabolites are actually biosynthesized by associated microorganisms. In this work, we show that the original source organism(s) responsible for the biosynthesis of the important anticancer and cytotoxic compound maytansine is the endophytic bacterial community harbored specifically within the roots of Putterlickia verrucosa and P. retrospinosa plants. Evaluation of the root endophytic community by chemical characterization of their fermentation products using HPLC-HRMS(n), along with a selective microbiological assay using the maytansine-sensitive type strain Hamigera avellanea revealed the endophytic production of maytansine. This was further confirmed by the presence of AHBA synthase genes in the root endophytic communities. Finally, MALDI-imaging-HRMS was used to demonstrate that maytansine produced by the endophytes is typically accumulated mainly in the root cortex of both plants. Our study, thus, reveals that maytansine is actually a biosynthetic product of root-associated endophytic microorganisms. The knowledge gained from this study provides fundamental insights on the biosynthesis of so-called plant metabolites by endophytes residing in distinct ecological niches.
- Published
- 2014
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47. Tramadol--a true natural product?
- Author
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Kusari S, Tatsimo SJ, Zühlke S, Talontsi FM, Kouam SF, and Spiteller M
- Subjects
- Biological Products chemistry, Cameroon, Reference Standards, Tandem Mass Spectrometry, Tramadol chemistry, Biological Products isolation & purification, Plant Roots chemistry, Rubiaceae chemistry, Tramadol isolation & purification
- Abstract
We have independently investigated the source of tramadol, a synthetic analgesic largely used for treating moderate to severe pain in humans, recently found in the roots of the Cameroonian medicinal plant, Nauclea latifolia. We found tramadol and its three major mammalian metabolites (O-desmethyltramadol, N-desmethyltramadol, and 4-hydroxycyclohexyltramadol) in the roots of N. latifolia and five other plant species, and also in soil and local water bodies only in the Far North region of Cameroon. The off-label administration of tramadol to cattle in this region leads to cross-contamination of the soil and water through feces and urine containing parent tramadol as well as tramadol metabolites produced in the animals. These compounds can then be absorbed by the plant roots and also leached into the local water supplies. The presence of tramadol in roots is, thus, due to an anthropogenic contamination with the synthetic compound., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2014
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48. Soil mineral composition matters: response of microbial communities to phenanthrene and plant litter addition in long-term matured artificial soils.
- Author
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Babin D, Vogel C, Zühlke S, Schloter M, Pronk GJ, Heister K, Spiteller M, Kögel-Knabner I, and Smalla K
- Subjects
- Biodegradation, Environmental, Biodiversity, DNA, Bacterial isolation & purification, DNA, Fungal isolation & purification, Environmental Pollutants chemistry, Manure, Phenanthrenes chemistry, Phylogeny, RNA, Ribosomal, 16S genetics, Environmental Pollutants pharmacology, Phenanthrenes pharmacology, Soil chemistry, Soil Microbiology
- Abstract
The fate of polycyclic aromatic hydrocarbons (PAHs) in soil is determined by a suite of biotic and abiotic factors, and disentangling their role in the complex soil interaction network remains challenging. Here, we investigate the influence of soil composition on the microbial community structure and its response to the spiked model PAH compound phenanthrene and plant litter. We used long-term matured artificial soils differing in type of clay mineral (illite, montmorillonite) and presence of charcoal or ferrihydrite. The soils received an identical soil microbial fraction and were incubated for more than two years with two sterile manure additions. The matured artificial soils and a natural soil were subjected to the following spiking treatments: (I) phenanthrene, (II) litter, (III) litter + phenanthrene, (IV) unspiked control. Total community DNA was extracted from soil sampled on the day of spiking, 7, 21, and 63 days after spiking. Bacterial 16S rRNA gene and fungal internal transcribed spacer amplicons were quantified by qPCR and subjected to denaturing gradient gel electrophoresis (DGGE). DGGE analysis revealed that the bacterial community composition, which was strongly shaped by clay minerals after more than two years of incubation, changed in response to spiked phenanthrene and added litter. DGGE and qPCR showed that soil composition significantly influenced the microbial response to spiking. While fungal communities responded only in presence of litter to phenanthrene spiking, the response of the bacterial communities to phenanthrene was less pronounced when litter was present. Interestingly, microbial communities in all artificial soils were more strongly affected by spiking than in the natural soil, which might indicate the importance of higher microbial diversity to compensate perturbations. This study showed the influence of soil composition on the microbiota and their response to phenanthrene and litter, which may increase our understanding of complex interactions in soils for bioremediation applications.
- Published
- 2014
- Full Text
- View/download PDF
49. Shifts in abundance and diversity of mobile genetic elements after the introduction of diverse pesticides into an on-farm biopurification system over the course of a year.
- Author
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Dealtry S, Holmsgaard PN, Dunon V, Jechalke S, Ding GC, Krögerrecklenfort E, Heuer H, Hansen LH, Springael D, Zühlke S, Sørensen SJ, and Smalla K
- Subjects
- Biotransformation, DNA, Bacterial chemistry, DNA, Bacterial genetics, Molecular Sequence Data, Plasmids, Polymerase Chain Reaction, Sequence Analysis, DNA, Bacteria genetics, Bacteria metabolism, Interspersed Repetitive Sequences, Metabolic Networks and Pathways genetics, Pesticides metabolism, Water Pollutants metabolism
- Abstract
Biopurification systems (BPS) are used on farms to control pollution by treating pesticide-contaminated water. It is assumed that mobile genetic elements (MGEs) carrying genes coding for enzymes involved in degradation might contribute to the degradation of pesticides. Therefore, the composition and shifts of MGEs, in particular, of IncP-1 plasmids carried by BPS bacterial communities exposed to various pesticides, were monitored over the course of an agricultural season. PCR amplification of total community DNA using primers targeting genes specific to different plasmid groups combined with Southern blot hybridization indicated a high abundance of plasmids belonging to IncP-1, IncP-7, IncP-9, IncQ, and IncW, while IncU and IncN plasmids were less abundant or not detected. Furthermore, the integrase genes of class 1 and 2 integrons (intI1, intI2) and genes encoding resistance to sulfonamides (sul1, sul2) and streptomycin (aadA) were detected and seasonality was revealed. Amplicon pyrosequencing of the IncP-1 trfA gene coding for the replication initiation protein revealed high IncP-1 plasmid diversity and an increase in the abundance of IncP-1β and a decrease in the abundance of IncP-1ε over time. The data of the chemical analysis showed increasing concentrations of various pesticides over the course of the agricultural season. As an increase in the relative abundances of bacteria carrying IncP-1β plasmids also occurred, this might point to a role of these plasmids in the degradation of many different pesticides., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)
- Published
- 2014
- Full Text
- View/download PDF
50. Analyses and decreasing patterns of veterinary antianxiety medications in soils.
- Author
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Choi JH, Lamshöft M, Zühlke S, Abd El-Aty AM, Rahman MM, Kim SW, Shim JH, and Spiteller M
- Subjects
- Adsorption, Anti-Anxiety Agents chemistry, Chromatography, High Pressure Liquid, Environmental Monitoring, Soil Pollutants chemistry, Tandem Mass Spectrometry, Veterinary Drugs chemistry, Anti-Anxiety Agents analysis, Soil Pollutants analysis, Veterinary Drugs analysis
- Abstract
An ultrasonic-assisted extraction method was developed to detect 16 antianxiety medications in soil samples using liquid chromatography-high resolution mass spectrometry (LC-HRMS), Orbitrap mass spectrometer. The determination method resulted in satisfactory sensitivity, linearity, recovery, repeatability, and within-laboratory reproducibility. Acepromazine, azaperone, and xylazine were incubated in control, amended, and sterilized soils. The amendment with powdered blood meal affected the relatively fast dissipations of acepromazine, azaperone, and xylazine in the soils. Dissipation kinetics of acepromazine were consistent with bi-phasic kinetics (first-order multi compartment) and the other couples were fit to single first-order kinetics. A hydroxylated acepromazine was identified from soil samples using Orbitrap mass spectrometry. According to sorption batch experiments, the adsorption of acepromazine and azaperone was greatly high, whereas that of xylazine was relatively low. Xylazine was persistent in the incubated soils, and acepromazine demonstrated fast initial dissipation; hence, xylazine could have a potential harmful effect on the environment. To the best of our knowledge, this is the first report on the dissipation and adsorption-desorption patters of animal pharmaceutical tranquilizers and α, β-blockers., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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