1,033 results on '"Chromatography, High Pressure Liquid"'
Search Results
2. [Development of an ivermectin-containing syrup as an extemporaneous preparation for treatment of scabies in children]
- Author
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Johannes, Wohlrab, L, Stadie, R H H, Neubert, and K, Bosse
- Subjects
Ivermectin ,Kindesalter ,Body-weight-adapted dosage ,Administration, Oral ,Orale Applikation ,Applikationshilfen ,Körpergewichtsadaptierte Dosierung ,Delivery aids ,Originalien ,Oral administration ,Scabies ,Child, Preschool ,Humans ,Off-label use ,Child ,Off-label-Anwendung ,Children ,Chromatography, High Pressure Liquid - Abstract
Oral ivermectin can be used to treat scabies. Evidence for safe and effective use in young children in individual treatment situations has been developed and published. In order to also ensure a body weight-adapted dosage for children, an ivermectin-containing syrup was developed as an extemporaneous preparation.Since ivermectin is not available as a pure substance for the formulation, tablets containing active ingredient were used as a basic material for development. The formulation was designed according to pharmaceutical, regulatory and use-oriented criteria. An HPLC (high-pressure liquid chromatography) method was developed and validated to demonstrate chemical stability. In order to facilitate the practical implementation, information on suitable packaging material and application aids was also developed and the formulation was evaluated.It has been demonstrated that the final formulation produced in the pharmacy was stable and can be stored for 3 weeks. No concerns were raised regarding the tolerability of the syrup formulation. The physicochemical properties and the taste of the formulation allow the intended use as a well-dosed syrup for children.The developed formulation meets the requirements of the Apothekenbetriebsordnung (Pharmacy Work Rules; Section 7 ApBetrO) and enables an exact, body weight-adapted dosage of oral ivermectin in young children. Studies on human pharmacokinetics or clinical studies to demonstrate tolerability and/or efficacy are not available for the formulation.HINTERGRUND: Zur Therapie der Skabies kann orales Ivermectin eingesetzt werden. Die Evidenz für einen sicheren und wirksamen Einsatz bei Kleinkindern im Einzelheilversuch ist erarbeitet worden und publiziert. Um eine körpergewichtsadaptierte Dosierung auch für Kinder zu gewährleisten, wurde ein Ivermectin-haltiger Saft als Magistralrezeptur entwickelt.Da Ivermectin nicht als Reinsubstanz für die Rezeptur zur Verfügung steht, wurden wirkstoffhaltige Tabletten als Ausgangsmaterial für die Entwicklung benutzt. Die Formulierung wurde entsprechend pharmazeutischer, regulatorischer und gebrauchsorientierter Kriterien konzipiert. Zum Nachweis der chemischen Stabilität wurde eine HPLC(Hochleistungsflüssigkeitschromatographie)-Methode erarbeitet und validiert. Um die praktische Umsetzung zu erleichtern, wurden zudem Angaben zu geeigneten Packmitteln und zu Applikationshilfen erarbeitet, und die Rezeptur wurde taxiert.Es konnte nachgewiesen werden, dass die finale Rezeptur stabil in der Apotheke hergestellt und über 3 Wochen gelagert werden kann. Es haben sich keine Bedenken bezüglich der Verträglichkeit des Rezeptursaftes ergeben. Die physikochemischen Eigenschaften und der Geschmack der Rezeptur ermöglichen den beabsichtigten Gebrauch als gut dosierbaren Saft für Kinder.Die entwickelte Rezeptur entspricht den Anforderungen der Apothekenbetriebsordnung (§ 7 ApBetrO) und ermöglicht eine exakte, körpergewichtsadaptierte Dosierung von oralem Ivermectin bei Kleinkindern. Untersuchungen zur Pharmakokinetik am Menschen bzw. klinische Studien zum Nachweis der Verträglichkeit und/oder Wirksamkeit liegen für die Rezeptur nicht vor.
- Published
- 2021
3. [Development of an ivermectin-containing syrup as an extemporaneous preparation for treatment of scabies in children].
- Author
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Wohlrab J, Stadie L, Neubert RHH, and Bosse K
- Subjects
- Administration, Oral, Child, Child, Preschool, Chromatography, High Pressure Liquid, Humans, Ivermectin therapeutic use, Scabies drug therapy
- Abstract
Background: Oral ivermectin can be used to treat scabies. Evidence for safe and effective use in young children in individual treatment situations has been developed and published. In order to also ensure a body weight-adapted dosage for children, an ivermectin-containing syrup was developed as an extemporaneous preparation., Materials and Methods: Since ivermectin is not available as a pure substance for the formulation, tablets containing active ingredient were used as a basic material for development. The formulation was designed according to pharmaceutical, regulatory and use-oriented criteria. An HPLC (high-pressure liquid chromatography) method was developed and validated to demonstrate chemical stability. In order to facilitate the practical implementation, information on suitable packaging material and application aids was also developed and the formulation was evaluated., Results: It has been demonstrated that the final formulation produced in the pharmacy was stable and can be stored for 3 weeks. No concerns were raised regarding the tolerability of the syrup formulation. The physicochemical properties and the taste of the formulation allow the intended use as a well-dosed syrup for children., Conclusion: The developed formulation meets the requirements of the Apothekenbetriebsordnung (Pharmacy Work Rules; Section 7 ApBetrO) and enables an exact, body weight-adapted dosage of oral ivermectin in young children. Studies on human pharmacokinetics or clinical studies to demonstrate tolerability and/or efficacy are not available for the formulation., (© 2021. The Author(s).)
- Published
- 2021
- Full Text
- View/download PDF
4. IDH1 und IDH2 Mutationen bei der akuten myeloischen Leukämie des jüngeren Erwachsenen : Analysen zur Inzidenz und klinischen Bedeutung
- Author
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Madar, Angelika, Paschka, Peter, and Cario, Holger
- Subjects
2-Hydroxyglutarat ,Akute myeloische Leukämie ,Isocitrat-Dehydrogenasen ,Isocitrate dehydrogenase ,AML ,DHPLC ,Leukemia, myeloid, acute ,IDH1 ,NPM1 ,ddc:610 ,IDH2 ,L-Ketoglutarat ,HPLC ,DDC 610 / Medicine & health ,Chromatography, high pressure liquid - Abstract
IDH1 (Isocitrate dehydrogenase 1) und IDH2 (Isocitrate dehydrogenase 2) Mutationen stellen rekurrente genetische Alterationen bei der akuten myeloischen Leukämie (AML) dar: Der Anteil an IDH1 und IDH2 Mutationen bei der AML liegt bei 15%-20%. Ziel der vorliegenden Arbeit war es, an einem großen Kollektiv (n=920) jüngerer AML Patienten (
- Published
- 2018
- Full Text
- View/download PDF
5. Comprehensive analysis of nine monoamines and metabolites in small amounts of peripheral murine (C57Bl/6J) tissues
- Author
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Joachim Nagler, Paul T. Pfluger, Meri De Angelis, Karl-Werner Schramm, and Sonja C. Schriever
- Subjects
Male ,medicine.medical_specialty ,Ecd ,Electrochemical Detection ,High-performance Liquid Chromatography ,Neurotransmitters ,Peripheral Tissues ,Adipose Tissue, White ,Clinical Biochemistry ,Hypothalamus ,White adipose tissue ,Diet, High-Fat ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,Mice ,03 medical and health sciences ,Norepinephrine ,chemistry.chemical_compound ,0302 clinical medicine ,Limit of Detection ,Dopamine ,Internal medicine ,Drug Discovery ,medicine ,Animals ,Glucose homeostasis ,Biogenic Monoamines ,Muscle, Skeletal ,Molecular Biology ,Chromatography, High Pressure Liquid ,Pharmacology ,Chromatography ,Chemistry ,010401 analytical chemistry ,Homovanillic acid ,Reproducibility of Results ,Electrochemical Techniques ,General Medicine ,0104 chemical sciences ,Mice, Inbred C57BL ,Endocrinology ,Epinephrine ,Monoamine neurotransmitter ,Organ Specificity ,Linear Models ,Serotonin ,Digestive System ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Monoamines, acting as hormones and neurotransmitters, play a critical role in multiple physiological processes ranging from cognitive function and mood to sympathetic nervous system activity, fight-or-flight response and glucose homeostasis. In addition to brain and blood, monoamines are abundant in several tissues, and dysfunction in their synthesis or signaling is associated with various pathological conditions. It was our goal to develop a method to detect these compounds in peripheral murine tissues. In this study, we employed a high-performance liquid chromatography method using electrochemical detection that allows not only detection of catecholamines but also a detailed analysis of nine monoamines and metabolites in murine tissues. Simple tissue extraction procedures were optimized for muscle (gastrocnemius, extensor digitorum longus and soleus), liver, pancreas and white adipose tissue in the range of weight 10-200 mg. The system allowed a limit of detection between 0.625 and 2.5 pg μL-1 for monoamine analytes and their metabolites, including dopamine, 3,4-dihydroxyphenylacetic acid, 3-methoxytyramine, homovanillic acid, norepinephrine, epinephrine, 3-methoxy-4-hydroxyphenylglycol, serotonin and 5-hydroxyindoleacetic acid. Typical concentrations for different monoamines and their metabolization products in these tissues are presented for C57Bl/6 J mice fed a high-fat diet.
- Published
- 2018
6. Quantification of steroid hormones in plasma using a surrogate calibrant approach and UHPLC-ESI-QTOF-MS/MS with SWATH-acquisition combined with untargeted profiling
- Author
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Michael Lämmerhofer, Manfred Hallschmid, and Bernhard Drotleff
- Subjects
0301 basic medicine ,Spectrometry, Mass, Electrospray Ionization ,Esi qtof ms ,medicine.medical_treatment ,Mass spectrometry ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,Steroid ,03 medical and health sciences ,Limit of Detection ,Tandem Mass Spectrometry ,Lipidomics ,medicine ,Humans ,Environmental Chemistry ,Data-independent acquisition ,Steroidomics ,Swath ,Data-independent Acquisition ,Estradiol ,Testosterone ,Clinical Analysis ,Chromatography, High Pressure Liquid ,Spectroscopy ,Chromatography ,Chemistry ,010401 analytical chemistry ,Reproducibility of Results ,Mass spectrometric ,Hormones ,0104 chemical sciences ,Triple quadrupole mass spectrometer ,030104 developmental biology ,Calibration ,Steroids ,Blood Chemical Analysis ,Hormone - Abstract
In spite of demonstrated lack of accuracy and consistency, quantification of steroid hormones is still most commonly executed via immunoassays. Mass spectrometric methods with triple quadrupole instruments are well established and, because of their proven robustness and sensitivity, best suited for targeted analysis. However, recent studies have shown that high-resolution mass spectrometers, like quadrupole time-of-flight instruments (QTOF), show comparable performance in terms of quantification and can generate additional sample information via untargeted profiling workflows. We demonstrate that adequate accuracy and selectivity for estradiol and testosterone can be achieved with a QTOF by data-independent acquisition with sequential window acquisition of all theoretical fragment-ion mass spectra (SWATH). Besides potential combination of targeted quantification and untargeted profiling, SWATH offers advantages with respect to sensitivity because the reduced total number of MS/MS experiments could be used to increase accumulation time without increasing cycle time. By applying a surrogate calibrant method leading to successful validation, a reliable method for absolute steroid quantification and high potential for steroid profiling has been developed. Linear calibration was achieved in the range from 10 to 1,000 pg mL−1 for 13C3-estradiol and from 20 to 15,000 pg mL−1 for 13C3-testosterone. Results for inter-day precision (13C3-estradiol: 4.5–10.2%; 13C3-testosterone: 5.1–7.8%) and inter-day accuracy (13C3-estradiol: 94.6–112.8%; 13C3-testosterone: 98.2–107.7%) were found to be well acceptable. Eventually, the method has been utilized to measure clinical samples of a study in which male volunteers obtained transdermal estradiol patches and sex hormone levels were quantified in plasma.
- Published
- 2018
7. Combined GC- and UHPLC-HR-MS Based Metabolomics to Analyze Durable Anti-fungal Resistance Processes in Cereals
- Author
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Simon G. Krattinger, Laurent Biglera, Lothar Willmitzer, Daniel Veyel, Rahel Bucher, Beat Keller, University of Zurich, and Bigler, Laurent
- Subjects
0106 biological sciences ,0301 basic medicine ,Chromatography, Gas ,Plant metabolomics ,Transgene ,Glyoxylate cycle ,Secondary Metabolism ,1600 General Chemistry ,580 Plants (Botany) ,Plant disease resistance ,Biology ,01 natural sciences ,03 medical and health sciences ,Metabolomics ,10126 Department of Plant and Microbial Biology ,Tandem Mass Spectrometry ,Plant defense ,Metabolome ,Plant defense against herbivory ,Secondary metabolism ,Gene ,QD1-999 ,Chromatography, High Pressure Liquid ,Triticum ,Disease Resistance ,Plant Diseases ,Plant Proteins ,2. Zero hunger ,Mass spectrometry ,business.industry ,Basidiomycota ,food and beverages ,Hordeum ,Oryza ,General Medicine ,General Chemistry ,Lipid Metabolism ,Biotechnology ,Lr34/yr18/sr57/pm38 ,Magnaporthe ,Chemistry ,030104 developmental biology ,Biochemistry ,business ,010606 plant biology & botany - Abstract
Introduction of durable resistance genes in crops is an important strategy to prevent yield loss caused by pathogens. The durable multi-pathogen resistance gene Lr34 originating from wheat is widely used in breeding, and is functionally transferable to barley and rice. The molecular resistance mechanism of Lr34, encoding for an adenosine triphosphate-binding cassette transporter, is not known yet. To understand the molecular function and the defense response of durable disease resistance in cereals, the metabolic response of Lr34 was investigated in, except for the Lr34 gene, genetically identical lines of barley, rice and wheat. A broad range of compounds including primary, secondary and lipophilic metabolites were analyzed by a combination of gas (GC) and liquid chromatography (LC) mass spectrometry (MS) based methods. Data from metabolomics correlated well with transcriptomics data for plant defense responses such as the formation of anti-fungal hordatines or the components of the glyoxylate cycle. Induction of the glyoxylate cycle found in transgenic Lr34 rice grown in the greenhouse was confirmed in field-grown natural Lr34 wheat. Constitutively active plant defense responses were observed in the different cereals.
- Published
- 2017
8. Assessing Cannabis Consumption Frequency: Is the Quantification of Free and Glucuronidated THCCOOH in Blood the Key?
- Author
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Marianne, Hädener, Wolfgang, Weinmann, and Stefan, König
- Subjects
610 Medicine & health ,Marijuana Smoking ,Column-switching chromatography ,Mass Spectrometry ,Blood analysis ,Substance Abuse Detection ,Lc-ms/ms ,Chemistry ,Glucuronides ,Humans ,Cannabis consumption frequency ,Dronabinol ,QD1-999 ,Chromatography, High Pressure Liquid ,Cannabis - Published
- 2016
- Full Text
- View/download PDF
9. Emerging pollutants and plants - metabolic activation of diclofenac by peroxidases
- Author
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Thomas Letzel, Martina Preis, Peter Schröder, Patricia J. Harvey, S. Grosse, and Christian Huber
- Subjects
Diclofenac ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Wastewater ,010501 environmental sciences ,01 natural sciences ,Armoracia ,Water Purification ,Activation, Metabolic ,chemistry.chemical_compound ,Tandem Mass Spectrometry ,medicine ,Humans ,Environmental Chemistry ,Chromatography, High Pressure Liquid ,Horseradish Peroxidase ,0105 earth and related environmental sciences ,Pollutant ,biology ,Chemistry ,010401 analytical chemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Contamination ,Pollution ,0104 chemical sciences ,Phytoremediation ,Biodegradation, Environmental ,Environmental chemistry ,Iminoquinone ,Lc-ms ,Peroxidase ,Stopped Flow Spectroscopy ,biology.protein ,Water treatment ,Sewage treatment ,Xenobiotic ,Oxidation-Reduction ,Water Pollutants, Chemical ,medicine.drug - Abstract
Human pharmaceuticals and their residues are constantly detected in our waterbodies, due to poor elimination rates, even in the most advanced waste water treatment plants. Their impact on the environment and human health still remains unclear. When phytoremediation is applied to aid water treatment, plants may transform and degrade xenobiotic contaminants through phase I and phase II metabolism to more water soluble and less toxic intermediates. In this context, peroxidases play a major role in activating compounds during phase I via oxidation. In the present work, the ability of a plant peroxidase to oxidize the human painkiller diclofenac was confirmed using stopped flow spectroscopy in combination with LC-MS analysis. Analysis of an orange colored product revealed the structure of the highly reactive Diclofenac-2,5-Iminoquinone, which may be the precursor of several biological conjugates and breakdown products in planta.
- Published
- 2016
10. Cardioprotection and lifespan extension by the natural polyamine spermidine
- Author
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Burkert Pieske, Uwe Primessnig, Johannes Beckers, Tobias Pendl, Thomas R. Pieber, Peter Willeit, Andreas Meinitzer, Luca Scorrano, Johann Willeit, Wolfgang A. Linke, Sophie H. Narath, Birgit Rathkolb, Alexander H. Kirsch, Helmut Fuchs, Jan Rozman, Mingming Tong, Christopher Dammbrueck, Dirk Janik, Tobias Eisenberg, Marion Horsch, Gert Trausinger, Andreas Zimmermann, Slaven Stekovic, Christian Mühlfeld, Sabrina Schroeder, Stefan Kiechl, Valerie Gailus-Durner, Patrick Rockenfeller, Didac Carmona-Gutierrez, Tarek Moustafa, Viktoria Herbst, Simon Sedej, Mahmoud Abdellatif, Kristin Moreth, Guido Kroemer, Frauke Neff, Albrecht Schmidt, Emilie Schrepfer, Alexandros Rahn, Alexandra Harger, Guenter Haemmerle, Federico Pietrocola, Stephan J. Sigrist, Raimund Pechlaner, Kathrin Eller, Joern Dengjel, Christoph Magnes, Junichi Sadoshima, Corinna Simonini, Manuel Mayr, Zehan Hu, Marion von Frieling-Salewsky, Julia Schipke, Sabrina Büttner, Angelina S. Gross, Christoph Ruckenstuhl, Martin Hrabé de Angelis, Oskar Knittelfelder, and Frank Madeo
- Subjects
0301 basic medicine ,Male ,Aging ,Spermidine ,Physiology ,Gene Expression ,Blood Pressure ,Mass Spectrometry ,Mitochondria, Heart ,Autophagy-Related Protein 5 ,chemistry.chemical_compound ,Mice ,Diastole ,Surveys and Questionnaires ,Mitophagy ,Connectin ,Myocytes, Cardiac ,Prospective Studies ,Phosphorylation ,Heart metabolism ,Chromatography, High Pressure Liquid ,2. Zero hunger ,Cardioprotection ,Heart ,General Medicine ,Middle Aged ,RC667 ,3. Good health ,Cardiovascular Diseases ,Echocardiography ,Cytokines ,Female ,QP517 ,Adult ,medicine.medical_specialty ,Cardiotonic Agents ,ATG5 ,Immunoblotting ,Longevity ,Cardiomegaly ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,Internal medicine ,medicine ,Autophagy ,Animals ,Humans ,QP506 ,Aged ,Heart Failure ,Inflammation ,Rats, Inbred Dahl ,Glucose Tolerance Test ,medicine.disease ,QP ,Diet ,Rats ,030104 developmental biology ,Endocrinology ,Blood pressure ,chemistry ,Heart failure ,Polyamine ,RC - Abstract
Aging is associated with an increased risk of cardiovascular disease and death. Here we show that oral supplementation of the natural polyamine spermidine extends the lifespan of mice and exerts cardioprotective effects, reducing cardiac hypertrophy and preserving diastolic function in old mice. Spermidine feeding enhanced cardiac autophagy, mitophagy and mitochondrial respiration, and it also improved the mechano-elastical properties of cardiomyocytes in vivo, coinciding with increased titin phosphorylation and suppressed subclinical inflammation. Spermidine feeding failed to provide cardioprotection in mice that lack the autophagy-related protein Atg5 in cardiomyocytes. In Dahl salt-sensitive rats that were fed a high-salt diet, a model for hypertension-induced congestive heart failure, spermidine feeding reduced systemic blood pressure, increased titin phosphorylation and prevented cardiac hypertrophy and a decline in diastolic function, thus delaying the progression to heart failure. In humans, high levels of dietary spermidine, as assessed from food questionnaires, correlated with reduced blood pressure and a lower incidence of cardiovascular disease. Our results suggest a new and feasible strategy for protection against cardiovascular disease.
- Published
- 2016
11. Identification and characterization of single nucleotide polymorphisms in 12 chicken growth-correlated genes by denaturing high performance liquid chromatography
- Author
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Qinghua Nie, Xiquan Zhang, Mingming Lei, Hua Zeng, Jian-hua Ouyang, Guanfu Yang, and Revues Inra, Import
- Subjects
Candidate gene ,lcsh:QH426-470 ,Growth hormone secretagogue receptor ,SNP ,Single-nucleotide polymorphism ,[SDV.GEN.GA] Life Sciences [q-bio]/Genetics/Animal genetics ,Growth hormone receptor ,Biology ,Quantitative trait locus ,Polymorphism, Single Nucleotide ,Denaturing high performance liquid chromatography ,03 medical and health sciences ,DHPLC ,Genetics ,Animals ,Genetics(clinical) ,Growth Substances ,genes ,Ecology, Evolution, Behavior and Systematics ,Chromatography, High Pressure Liquid ,030304 developmental biology ,DNA Primers ,lcsh:SF1-1100 ,2. Zero hunger ,0303 health sciences ,Base Sequence ,Research ,0402 animal and dairy science ,04 agricultural and veterinary sciences ,General Medicine ,040201 dairy & animal science ,Molecular biology ,[SDV.GEN.GA]Life Sciences [q-bio]/Genetics/Animal genetics ,lcsh:Genetics ,chickens ,Ghrelin ,Animal Science and Zoology ,lcsh:Animal culture ,hormones, hormone substitutes, and hormone antagonists ,Polymorphism, Restriction Fragment Length - Abstract
The genes that are part of the somatotropic axis play a crucial role in the regulation of growth and development of chickens. The identification of genetic polymorphisms in these genes will enable the scientist to evaluate the biological relevance of such polymorphisms and to gain a better understanding of quantitative traits like growth. In the present study, 75 pairs of primers were designed and four chicken breeds, significantly differing in growth and reproduction characteristics, were used to identify single nucleotide polymorphisms (SNP) using the denaturing high performance liquid chromatography (DHPLC) technology. A total of 283 SNP were discovered in 31 897 base pairs (bp) from 12 genes of the growth hormone (GH), growth hormone receptor (GHR), ghrelin, growth hormone secretagogue receptor (GHSR), insulin-like growth factor I and II (IGF-I and -II), insulin-like growth factor binding protein 2 (IGFBP-2), insulin, leptin receptor (LEPR), pituitary-specific transcription factor-1 (PIT-1), somatostatin (SS), thyroid-stimulating hormone beta subunit (TSH-β). The observed average distances in bp between the SNP in the 5'UTR, coding regions (non- and synonymous), introns and 3'UTR were 172, 151 (473 and 222), 89 and 141 respectively. Fifteen non-synonymous SNP altered the translated precursors or mature proteins of GH, GHR, ghrelin, IGFBP-2, PIT-1 and SS. Fifteen indels of no less than 2 bps and 2 poly (A) polymorphisms were also observed in 9 genes. Fifty-nine PCR-RFLP markers were found in 11 genes. The SNP discovered in this study provided suitable markers for association studies of candidate genes for growth related traits in chickens.
- Published
- 2005
12. [What is exactly alike? High-performance analytics for development of biosimilars]
- Author
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Martin, Blüggel
- Subjects
Humans ,Legislation, Drug ,Biosimilar Pharmaceuticals ,Chromatography, High Pressure Liquid ,Mass Spectrometry - Published
- 2013
13. How to Increase the Safety and Efficacy of Compounds against Neurodegeneration? A Multifunctional Approach
- Author
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Alessandra Nurisso, Amandine Guillot, Sophie Martel, Claudia A. Simões-Pires, Pierre-Alain Carrupt, and Delphine Cressend
- Subjects
Drug ,In silico ,media_common.quotation_subject ,Computational biology ,Neuroprotection ,Antioxidants ,Human health ,Antioxidant activity ,medicine ,Humans ,Computer Simulation ,Neurodegeneration ,QD1-999 ,Chromatography, High Pressure Liquid ,media_common ,Drug candidate ,business.industry ,Neurodegenerative Diseases ,General Medicine ,General Chemistry ,medicine.disease ,Bioconcentration ,Chemistry ,Neuroprotective Agents ,Hdac ,Environmental Pollution ,business ,Algorithms ,Potential toxicity - Abstract
Successful drug design requires not only the detailed knowledge of the pharmacokinetic and pharmacodynamic profiles of the drug candidate portfolio but also a thorough documentation of the possible toxic effects on humans and the environment. Thus, experimental and computational strategies able to measure or predict specific profiles of designed compounds related to their potential toxicity are highly desired. Moreover, a strategy to avoid toxic effects thus enhancing the potential efficacy of drug candidates is of great interest. To fulfil this aim, the pharmacochemistry research unit at the EPGL has recently developed and improved methodologies that detect the potential human health and environmental hazards of compounds active against neurodegeneration at an early stage. A three-step strategy is presented herein. In particular, i) an alternative index to model the bioconcentration of chemicals in the environment was determined; ii) the antioxidant activity of chemical species against free radicals was evaluated. Moreover, since antioxidants play a key role in both toxicity prevention and neuroprotection, iii) the potential interaction of such compounds with enzymatic targets involved in the neurodegenerative cascade was investigated in silico.
- Published
- 2012
14. New Insights in Pharmaceutical Analysis
- Author
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Jean-Luc Veuthey, Serge Rudaz, Julien Boccard, Davy Guillarme, and Julie Schappler
- Subjects
Toxicological analysis ,Process (engineering) ,Computer science ,Analytical chemistry ,Liquid chromatography ,Field (computer science) ,Capillary electrophoresis ,Knowledge extraction ,Data Mining ,Metabolomics ,Sensitivity (control systems) ,Chemometrics ,QD1-999 ,Chromatography, High Pressure Liquid ,ddc:615 ,Mass spectrometry ,Design of experiments ,Electrophoresis, Capillary ,Chromatography, Supercritical Fluid ,General Medicine ,General Chemistry ,Reference Standards ,Chemistry ,Metabolism ,Pharmaceutical Preparations ,Fast analysis ,Supercritical fluid chromatography ,Biochemical engineering ,Relevant information ,Chromatography, Liquid - Abstract
The research unit of pharmaceutical analytical chemistry (PAC) has been active in the field of separation sciences for many years. Liquid chromatography (LC) and its latest improvements such as ultra-high performance chromatography (UHPLC) and supercritical fluid chromatography (SFC) are deeply and thoroughly studied, from a fundamental viewpoint to its various application capabilities. Electro-driven separations such as capillary electrophoresis (CE) are also a major field of interest, especially for macromolecules, and low cost. All these techniques are investigated with various detection modes including mass spectrometry (MS) for various applications where high sensitivity and selectivity is needed. Extracting the relevant information from the overwhelming amount of data generated by modern analytical platforms has become an important issue for knowledge discovery in various research fields. The appropriate treatment of such data is therefore of crucial importance to provide valuable information. Numerous works in our research group have demonstrated the usefulness of statistical and mathematical methodologies to improve quality of the results. Therefore, well-established chemometric approaches (e.g. design of experiments, multivariate data analysis, etc.) are implemented to optimize the analytical process from method development to data analysis.
- Published
- 2012
15. Zebrafish Bioassay-guided Microfractionation for the Rapid in vivo Identification of Pharmacologically Active Natural Products
- Author
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Soura Challal, Olivia Erin M Buenafe, Alexander D. Crawford, Peter de Witte, Nadine Bohni, Jean-Luc Wolfender, and Camila V. Esguerra
- Subjects
Isolation procedures ,Uhplc-tof-ms ,Mass Spectrometry ,In vivo ,Bioassay ,Animals ,Zebrafish ,QD1-999 ,Chromatography, High Pressure Liquid ,Biological Products ,Natural products ,Chromatography ,biology ,Drug discovery ,Chemistry ,Microflow nmr ,General Medicine ,General Chemistry ,biology.organism_classification ,Small molecule ,Rapid acquisition ,Biochemistry ,Active compound ,Biological Assay ,Microfractionation - Abstract
The rapid acquisition of structural and bioactivity information on natural products (NPs) at the sub- milligram scale is key for performing efficient bioactivity-guided isolations. Zebrafish offer the possibility of rapid in vivo bioactivity analysis of small molecules at the microgram scale – an attractive feature when combined with high-resolution fractionation technologies and analytical methods such as UHPLC-TOF-MS and microflow NMR. Numerous biomedically relevant assays are now available in zebrafish, encompassing most indication areas. Zebrafish also provide the possibility to screen bioactive compounds for potential hepato-, cardio-, and neurotoxicities at a very early stage in the drug discovery process. Here we describe two strategies using zebrafish bioassays for the high-resolution in vivo bioactivity profiling of medicinal plants, using either a one-step or a two-step procedure for active compound isolation directly into 96-well plates. The analysis of the microfractions by microflow NMR in combination with UHPLC-TOF-MS of the extract enables the rapid dereplication of compounds and an estimation of their microgram quantities for zebrafish bioassays. Both the one-step and the two-step isolation procedures enable a rapid estimation of the bioactive potential of NPs directly from crude extracts. In summary, we present an in vivo , microgram-scale NP discovery platform combining zebrafish bioassays with microscale analytics to identify, isolate and evaluate pharmacologically active NPs.
- Published
- 2012
16. A Streamlined Synthesis of Androstadiene C-17 Ester Derivatives
- Author
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Manuela Seeger-Weibel, Fabrice Gallou, and Daniel Lupp
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Ester derivatives ,Magnetic Resonance Spectroscopy ,Esterification ,Androstadiene ,Reaction mass intensity ,Oxidation reduction ,General Medicine ,General Chemistry ,Process mass intensity ,Combinatorial chemistry ,E-factor ,Androstadienes ,Solvent ,Environmental impact ,chemistry.chemical_compound ,Chemistry ,chemistry ,Cyclization ,Yield (chemistry) ,Green metrics ,Oxidation-Reduction ,Telescope ,QD1-999 ,Chromatography, High Pressure Liquid ,Derivative (chemistry) - Abstract
The development of a fully telescoped synthesis of a derivative of androstadiene C-17 esters made from epoxyparamethasone was demonstrated. This streamlining allowed for the elimination of isolation and solvent change after each synthetic step. Thus it not only drastically reduced the solvent waste, but also minimized the potential exposure to highly active intermediates thereby increasing the overall yield. The intuitively obvious advantage inherent to lowering the number of solvents was illustrated by applying standard green metrics.
- Published
- 2011
17. [Hydrogelexpander as drug delivery system for antibiotics]
- Author
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M P, Schittkowski, R F, Guthoff, B, Drewelow, and R, Wacke
- Subjects
Drug Carriers ,Ofloxacin ,Metabolic Clearance Rate ,Infant, Newborn ,Administration, Ophthalmic ,Hydrogels ,Anti-Bacterial Agents ,Drug Delivery Systems ,Fluorescence Polarization Immunoassay ,Tobramycin ,Humans ,Surgical Wound Infection ,Algorithms ,Chromatography, High Pressure Liquid - Abstract
The suitability of a high-hydrophilic osmotic self-inflating hydrogel expander consisting of a co-polymer of N-vinylpyrolidone and methyl methacrylate as a drug delivery system for antibiotics to prevent a postoperative infection was investigated in a laboratory setting.The dry expanders were incubated in a 0.3 % solution of Ofloxacin or Tobramycin for 24 hours. The completely swollen expander had increased in volume from 0.3 mL to almost 3 mL (adsorbing 2.7 mL of the 0.3 % solution, i. e.,8.1 mg of Ofloxacin or Tobramycin, respectively). Addressing the elimination of both antibiotics, the concentrations in 15 mL elution medium (simulating the volume of the orbit in a newborn baby) were measured after 0.25, 1, 2, 6, 24, 48 and 72 hours of elution. 0.9 % sodium chloride (B. Braun Melsungen, Germany) was used as elution medium. To imitate fluid exchange due to blood perfusion in the surrounding tissue the medium was renewed after every sampling. For each substance 10 expanders were tested. Concentrations of antibiotic were determined by HPLC/UV for Ofloxacin and by using a specific fluorescence-polarisation immunoassay (Abbott TDx) for Tobramycin.Mean concentrations of Ofloxacin at 0.25, 1, 2, 6, 24, 48 and 72 hours after beginning of the elution were 50.2, 46.8, 41.2, 75.4, 88.2, 46.2 and 19.1 µg/mL, respectively. The cumulative amount of Ofloxacin eluted after 72 hours reached 68 % of the loading dose. The corresponding mean concentrations of Tobramycin were 38.8, 48.5, 40.5, 69.8, 88.7, 119.3 and 71.6 µg/mL. The cumulative eluted amount was 88 %.The investigated hydrogel expanders soaked in 0.3 % antibiotic solution can store and later on release sufficient amounts of Ofloxacin or Tobramycin to produce antimicrobial effective concentrations in vitro in the surrounding environment. This principle, when used in a clinical setting, might help to eliminate post-implantation infection which is one of the major complications in clinical use.
- Published
- 2011
18. [Determination of blood/serum ratios of different forensically relevant analytes in authentic samples]
- Author
-
Ricarda, Jantos, Markus, Schuhmacher, Janet L, Veldstra, Wendy M, Bosker, Ineke, Klöpping-Ketelaars, Katerina, Touliou, Gian Marco, Sardi, Karel A, Brookhuis, Johannes G, Ramaekers, Rainer, Mattern, and Gisela, Skopp
- Subjects
Serum ,Psychotropic Drugs ,Tandem Mass Spectrometry ,Humans ,Sensitivity and Specificity ,Blood Chemical Analysis ,Chromatography, High Pressure Liquid ,Xenobiotics - Abstract
For forensic toxicological investigations only whole blood, but no serum is often available. Pharmacokinetic data are helpful for interpreting the results, but most of these studies indicate serum or plasma concentrations. In order to obtain reliable conversion factors which also take intersubject variability into account, the blood/serum ratios (B/S) of oxycodone, morphine, fentanyl, hydromorphone, zopiclone, MDMA, dexamphetamine, alprazolam, risperidone and 9-hydroxyrisperidone were determined by LC-MS/MS using authentic samples. Blood and corresponding serum samples were obtained from driving studies performed with controlled or known dosages of the above drugs. The analytes were analysed in blood and serum and the following mean B/S ratios (relative standard deviations) were determined: oxycodone 1.48 (8.19 %); morphine 1.03 (3.59 %); fentanyl 0.87 (13.9 %); hydromorphone 1.04 (8.11 %); zopiclone 0.89 (16.1 %); MDMA 1.19 (8.04 %); dexamphetamine 0.89 (10.9 %); alprazolam 0.81 (5.84 %); risperidone 0.65 (7.52 %); 9-hydroxyrisperidone 0.73 (12.3 %). These mean values are largely in line with those reported in the literature. The B/S ratios did not appear to depend on partition coefficients, whereas there was strong evidence that B/S ratios decreased with increasing plasma protein binding.
- Published
- 2011
19. [Induction of occupational leucoderma and vitiligo. Can butylated hydroxytoluene induce vitiligo similarly to p-tert-butylphenol?]
- Author
-
H C, Broding, C, Monsé, T, Brüning, and M, Fartasch
- Subjects
Adult ,Hypopigmentation ,Male ,Dermatitis, Occupational ,Phenols ,Universities ,Medical Laboratory Personnel ,Vitiligo ,Humans ,Butylated Hydroxytoluene ,Antioxidants ,Chromatography, High Pressure Liquid - Abstract
While vitiligo is usually idiopathic, some cases are caused by chemicals. If occupational exposure to p-tert-butylphenol (ptBP) leads to vitiligo, the legal requirements for occupational disease Nr. 1314 can be fulfilled in Germany. Chemicals of similar structure can induce local and more widespread symmetrical depigmentation with genital involvement, making the differential diagnosis more complicated. Occupationally caused depigmentation from other chemicals can also be treated according to § 9 sec. 2 of the occupational disease regulations.Some substances can cause leukoderma only in animals; others in animals and humans; in some cases systemic vitiligo-like changes develop. The effects on human skin cannot always be predicted from the structural analogies of the involved chemicals.Based on a case of occupational exposure to butyl hydroxytoluene with possible induction of vitiligo, a careful updated literature analysis of substances inducing depigmentation is presented.The literature contains discrepancies in the evidence for the ability of some substances-especially BHT-to cause vitiligo. A more exact analysis indicates that BHT does not cause vitiligo or leukoderma.
- Published
- 2011
20. Membranes for Specific Adsorption: Immobilizing Molecularly Imprinted Polymer Microspheres using Electrospun Nanofibers
- Author
-
Christian Adlhart, Roman Büttiker, Christian Hinderling, and Jürgen Ebert
- Subjects
Vinyl Compounds ,Polymers ,Cinchona Alkaloids ,Nanofibers ,Precipitation polymerization ,Biocompatible Materials ,Spectrum Analysis, Raman ,620: Ingenieurwesen ,Molecular Imprinting ,ICBC ,chemistry.chemical_compound ,Raman microscopy ,Materials Testing ,Spectroscopy, Fourier Transform Infrared ,Electrochemistry ,QD1-999 ,Chromatography, High Pressure Liquid ,chemistry.chemical_classification ,Molecularly imprinted polymer ,Electrospinning ,Chemistry ,Polyacrylonitrile ,Membranes, Artificial ,General Medicine ,General Chemistry ,Polymer ,Divinylbenzene ,Microspheres ,Membrane ,Chemical engineering ,Nanofiber ,Microscopy, Electron, Scanning ,Filtration - Abstract
Molecularly imprinted polymer microspheres were immobilized within a polymer nanofiber membrane by electrospinning. Such membranes simplify the handling of functional microspheres and provide specific recognition capabilities for solid-phase extraction and filtration applications. In this study, microspheres were prepared by precipitation polymerization of methacrylic acid and divinylbenzene as a cross-linker with the target molecule (?)-cinchonidine and then, they were electrospun into a non-woven polyacrylonitrile nanofiber membrane. The composite membrane showed specific affinity for (?)-cinchonidine which was attributed to the functional microspheres as confirmed by Raman microscopy. The target molecule capturing capacity of the composite membrane was 5 mg/g or 25 mg/g immobilized functional microsphere. No difference in target affinity was observed between the immobilized microspheres and the free microspheres. These results reveal that electrospun composite membranes are a feasible approach to immobilizing functional microspheres.
- Published
- 2011
21. Diabetes mellitus: The long way of standardization of HbA1c to the level of highest metrological order
- Author
-
Kaiser, Patricia and Reinauer, Hans
- Subjects
Blood Glucose ,Glycated Hemoglobin ,standardization ,lcsh:R ,HbA1c-Referenzmessverfahren ,lcsh:Medicine ,610 Medical sciences ,Medicine ,Reference Standards ,Article ,LC-ID-MS ,Standardisierung ,HbA1c reference measurement procedure ,LC-IDMS ,ddc: 610 ,Germany ,Practice Guidelines as Topic ,Diabetes Mellitus ,Chromatography, High Pressure Liquid - Abstract
Glycated haemoglobin (HbA1c) measurements are used in clinical studies and for the management of diabetic patients. Various efforts were made to standardize the HbA1c measurements with consensus standards and standards based on a reference measurement procedure with external calibration. According to ISO 17511 a standard should meet highest accuracy possible, have a defined uncertainty of measurement and the calibration should be traceable to SI units. For HbA1c this has been realized using a LC-ID-MS procedure based on the existing reference measurement procedure., GMS German Medical Science; 9:Doc28; ISSN 1612-3174
- Published
- 2011
22. [Measurement of thiamine concentration in the cat using high pressure liquid chromatography]
- Author
-
Carola, Leithäuser, H C, Schenk, M, Höltershinken, and A, Tipold
- Subjects
Male ,Cats ,Animals ,Thiamine Deficiency ,Female ,Thiamine ,Thiamine Pyrophosphate ,Cat Diseases ,Chromatography, High Pressure Liquid ,Retrospective Studies - Abstract
Thiamine deficiency in cats frequently leads to a dysfunction of the central nervous system including vestibular signs with fatal outcome in untreated cases. The aim of the present study was to directly measure thiamine concentrations using high pressure liquid chromatography (HPLC) in feline blood samples and to evaluate values in healthy and diseased cats.Blood samples (1 ml EDTA-whole blood) from 193 cats were analysed for total thiamine and thiamine diphosphate using HPLC. For the interpretation of the results cats were retrospectively assigned to six groups: A) healthy cats, B) cats with diseases of the gastrointestinal tract, C) cats with different traumas not affecting the gastrointestinal tract, D) cats with inappetence, cats with central vestibular signs and normal (E) or low values of thiamine (F), respectively.In animals of group F no obvious cause for the vestibular signs was found and spontaneous recovery after thiamine application occurred in three cats. Therefore thiamine deficiency was a highly likely clinical diagnosis. Total thiamine concentration (mean 48.2 µg/l, standard deviation ± 22.6) of group F significantly differered from the other groups (group A-D: p0.01, group E: p0.001). Comparable results were obtained for thiamine diphosphate. However, low total thiamine values were also found in cats with inappetence without any neurological signs.In the present study a method for direct measurement of thiamine formerly established for ruminants was evaluated for cats. A more accurate and objective clinical diagnosis of thiamine deficiency is feasible in cats with values less than 50 µg/l and typical clinical signs. In animals with values of total thiamine levels between 50-70 µg/l a prophylactic substitution of thiamine can be discussed.
- Published
- 2010
23. [Average blood glucose instead of HbA1c?]
- Author
-
E, Schleicher
- Subjects
Blood Glucose ,Glycated Hemoglobin ,Diabetes Mellitus, Type 1 ,Diabetes Mellitus, Type 2 ,Patient Education as Topic ,Communication ,Consensus Development Conferences as Topic ,Humans ,Reference Standards ,Peptide Mapping ,Chromatography, High Pressure Liquid - Published
- 2009
24. [Thiamine and its derivates in cattle blood measured by HPLC in healthy animals, in patients suffering from CCN and in their cohorts]
- Author
-
M, Höltershinken, A, Höhling, B, Witte, and H, Scholz
- Subjects
Cerebral Cortex ,Brain Diseases ,Necrosis ,Animals ,Cattle Diseases ,Reproducibility of Results ,Thiamine Deficiency ,Cattle ,Thiamine ,Thiamine Pyrophosphate ,Sensitivity and Specificity ,Thiamine Monophosphate ,Chromatography, High Pressure Liquid - Abstract
The aim of this project was to develop a routine method to measure thiamine and its derivates in blood, to detect the need of vitamin B1-supply in cattle faster and more precise than until now using the transketolase test. For that, thiamine and its derivates (thiaminediphosphate = TDP,-monophosphate = TMP) were analysed in cattle blood by HPLC technique with post-column derivatization. Moreover, the levels in healthy cattle were compared with those in herds with single CCN cases. EDTA-blood-stored up to 10 days by 6 or 20 degrees C- was the most appropriate substrate. Sensitivitiy and specifity were significantly better than (TT, sum of all fractions): 1.95% and 2.10%; thiamine and TMP: 7.02% and 9.17%. The lowest concentration, which could be measured, was 0.5 ng/ml. 72 samples could be analysed daily. In the blood of 280 healthy calves and cows (group A), 201 clinically unsuspicious animals out of stocks with single cases of CCN (group B) and 12 patients with clinical obvious CCN (group C), thiamine and its phosphates were measured and the means calculated (ng/ml). After this, the thiamine status is characterized by (ng/ml): (A) thiamine 13.5 (4.61-28.8),TDP 51.0 (33.1-82.2), TMP 8.79 (2.23-18.1),TT 73.3 (44.6-114); (B) thiamine 8.73 (0.00-20.0), TDP 43.5 (15.5-75.7),TMP 6.15 (0.00-16.6), TT 59.4 (18.7-96.5); (C) thiamine 3.85 (0.00-1 1.5), TDP 14.5 (0.00-28.3), TMP 1.27 (0.00-4.87), TTP 19.6 (4.92-35.9). So, HPLC with post-column derivatization offers a precise, automatically working method for a fast diagnose of thiamine deficiency. The lowest critical value of TT is 40 ng/ml for healthy animals in the blood. The sample (EDTA-blood) can be posted simply at temperatures up to 20 degrees C. In comparison to other measuring methods, this HPLC-technique enables an early recognition of the risk to come down with CCN in endangered cattle herds.
- Published
- 2007
25. [New trends in HPLC in 2006]
- Author
-
Sami, El Deeb, Lutz, Preu, and Hermann, Wätzig
- Subjects
Chemistry, Pharmaceutical ,Solvents ,Stereoisomerism ,Chromatography, High Pressure Liquid ,Mass Spectrometry - Published
- 2006
26. [Stability of busulfan injection solution (Busilvex, Busulfex) in B/Braun Injekt syringes]
- Author
-
A, Karstens and I, Krämer
- Subjects
Pharmaceutical Solutions ,Light ,Drug Storage ,Syringes ,Calibration ,Temperature ,Indicators and Reagents ,Spectrophotometry, Ultraviolet ,Antineoplastic Agents, Alkylating ,Busulfan ,Chromatography, High Pressure Liquid - Abstract
Stability of busulfan injection solution (Busilvex, Busulfex) in B/Braun Injekt syringes Stability of busulfan injection was determined by a modified stability-indicating HPLC method with UV detection. Diethyldithiocarbamate was used as derivatization agent. The stability tests revealed that busulfan injection (Busilvex, Busulfex) stored in B/Braun Injekt syringes at 18-20 degrees C without light protection or refrigerated are stable for up to 28 days. Unused busulfan injection (Busilvex, Busulfex) is not necessarily to be discarded, but can be stored for a prolonged period of time in a rubber free syringe, preferably under refrigeration.
- Published
- 2006
27. [Studies on the recovery of pharmaceutical drug substances from surfaces made of defined stainless-steel alloys]
- Author
-
S, Kloss, U, Müller, and H, Oelschläger
- Subjects
Chromium ,Titanium ,Drug Industry ,Surface Properties ,Drug Compounding ,Stainless Steel ,Solutions ,Pharmaceutical Preparations ,Nickel ,Alloys ,Indicators and Reagents ,Algorithms ,Chromatography, High Pressure Liquid ,Copper - Abstract
Facilities for the manufacturing of pharmaceutical drug substances on the pilot-plant and the industrial scale as well as chemical reactors and vessels used for chemical work-up mainly consist of alloyed stainless steel. The influence of the alloy composition and the surface condition, i.e. of the roughness of the stainless-steel materials, on the adsorption of structurally diverse steroidal substances and, hence, on the quality of the products was studied. In general, stainless-steel alloys with smooth, not so rough surfaces are to be favored as reactor material. However, it was demonstrated in this study that, on account of the weak interaction between active substances and steel materials, mechanically polished materials of a medium roughness up to approx. 0.4 microm can be employed instead of the considerably more cost-intensive electrochemically polished stainless-steel surfaces. The type of surface finishing up to a defined roughness, then, has no influence on the quality of these pharmaceutical products. Substances that, because of their molecular structure, can function as "anions" in the presence of polar solvents, are adsorbed on very smooth surfaces prepared by electrochemical methods, forming an amorphous surface film. For substances with this structural characteristics, the lower-cost mechanically polished reactor materials of a medium roughness up to approx. 0.5 microm should be used exclusively.
- Published
- 2005
28. [Radioimmunotherapy with yttrium-90 ibritumomab tiuxetan. Clinical considerations, radiopharmacy, radiation protection, perspectives]
- Author
-
K, Schomäcker, M, Dietlein, R, Schnell, J, Pinkert, W, Eschner, B, Zimmermanns, T, Fischer, A, Engert, and H, Schicha
- Subjects
Quality Control ,Neutropenia ,Radiation Protection ,Lymphoma ,Antibodies, Monoclonal ,Humans ,Anemia ,Yttrium Radioisotopes ,Radioimmunotherapy ,Radionuclide Imaging ,Thrombocytopenia ,Chromatography, High Pressure Liquid - Abstract
90Y-ibritumomab tiuxetan (Zevalin) is currently approved for radioimmunotherapy of patients with relapsed or refractory follicular non-Hodgkin's lymphoma pretreated with rituximab. Future directions are the combined use of 90Y-ibritumomab tiuxetan as part of the initial treatment and as first-line multi-agent therapy of relapsed disease. Current studies investigate patients with other than follicular indolent histologies, e. g. diffuse large cell lymphoma. Labelling of 90Y ibritumomab tiuxetan is a safe procedure, the radiochemical purity is not disturbed by a higher room temperature or by metallic impurity. Quality control is recommended by thin layer chromatography (TLC), strips15 cm are favourable. TLC cannot distinguish between the correctly radiolabelled antibodies and radiocolloid impurity. If necessary, additional HPLC should be performed. Radiocolloid impurities are absorbed to the solid phase and do not reach the eluate. If the radiochemical purity test is insufficient (95%), the additional cleaning using EconoPac 10 DG columns (Biorad, Hercules, CA, USA) is a reliable procedure to reduce the percentage of free radionuclide. However, this procedure is not part of the approval.
- Published
- 2005
29. [Magnetic Drug Targeting--a new approach in locoregional tumor therapy with chemotherapeutic agents. Experimental animal studies]
- Author
-
C, Alexiou, R, Jurgons, R, Schmid, W, Erhardt, F, Parak, C, Bergemann, and H, Iro
- Subjects
Drug Carriers ,Otorhinolaryngologic Neoplasms ,Drug Delivery Systems ,Carcinoma, Squamous Cell ,Animals ,Infusions, Intra-Arterial ,Antineoplastic Agents ,Ferrous Compounds ,Rabbits ,Mitoxantrone ,Chromatography, High Pressure Liquid ,Nanostructures - Abstract
Advanced squamous cell carcinomas of the head and neck region were often treated with combined radio-chemotherapy. Radiotherapy allows a focused treatment of the tumor, and healthy tissue can be protected from radiation. Chemotherapy, however, is mostly given systemically and the unwanted negative side effects also develop in many other organs.Locoregional application of chemotherapeutic agents with Magnetic Drug Targeting on an animal experimental study.Magnetic Drug Targeting is a new approach to the locoregional treatment of tumors. Ferrofluids (colloidal dispersion of magnetic nanoparticles) were reversibly bound to chemotherapeutic agents and injected intra-arterially, while focused with an external magnetic field to a certain body compartment (i.e. the tumor). With only 20% or 50% percent of the regular systemic chemotherapeutic dose, we achieved an up to 26 times higher concentration in the tumor region with this application compared to the usual systemic administration.Magnetic Drug Targeting offers an unique opportunity to treat tumors locoregionally with chemotherapeutic agents.
- Published
- 2004
30. [Liberation of hydrocortisone acetate from different commercial formulations]
- Author
-
R H H, Neubert and A, Pötzsch
- Subjects
Excipients ,Ointments ,Hydrocortisone ,Area Under Curve ,Chemistry, Pharmaceutical ,Anti-Inflammatory Agents ,Solvents ,Biological Availability ,Membranes, Artificial ,Chromatography, High Pressure Liquid ,Permeability - Abstract
Liberation of hydrocortisone acetate from different commercial formulations In this article the release of hydrocortisone acetate (HC-acetate) from three commercial semisolid formulations (Ebeno-ointment, Soventol HC cream and Fenistil hydrocortisone ointment) was measured by means of a multilayer membrane system (MLMS) described in the literature. The formulations are different regarding rate and extent of the release of HC-acetate. The release of HC-acetate form the Soventol HC cream is very fast and results in high topical availability. In contrast, HC-acetate shows a sustained release from the Fenistil hydrocortisone ointment. The release of HC-acetate from the Ebenol-ointment is between that of the Soventol HC cream and that of the Fenistil-ointment. In summary, HC-acetate shows a shorter mean liberation time (MDT) and a higher topical availability from Soventol HC cream in comparison to the other formulations studied.
- Published
- 2004
31. [Epitheliotrophic capacity of serum and plasma eyedrops. Influence of centrifugation]
- Author
-
P, Herminghaus, G, Geerling, D, Hartwig, T, Wedel, and L, Dibbelt
- Subjects
Platelet-Derived Growth Factor ,Serum ,Dose-Response Relationship, Drug ,Epidermal Growth Factor ,Cell Survival ,Platelet Count ,Epithelium, Corneal ,Centrifugation ,Enzyme-Linked Immunosorbent Assay ,Blood Proteins ,Fibronectins ,Adenosine Triphosphate ,Transforming Growth Factor beta ,Microscopy, Electron, Scanning ,Humans ,Ophthalmic Solutions ,Vitamin A ,Chromatography, High Pressure Liquid ,Cell Line, Transformed - Abstract
Serum eyedrops are a new modality for the treatment of ocular surface disorders. We examined the influence of the preparation of blood products in a cell culture model and compared it with plasma.Serum and plasma were obtained from full blood of ten healthy volunteers and centrifuged at 500 and 3000 G. EGF, PDGF, TGF-beta1, fibronectin, and vitamin A were quantified by means of ELISA and HPLC. Cultures of human corneal epithelial cells were incubated with the four blood products in dose-response experiments and the intracellular ATP quantified.EGF, PDGF, and vitamin A were present in serum in significantly higher concentrations than in plasma. The concentration of fibronectin was not influenced by the preparation. Support of proliferation was best by 25% platelet-poor serum. Serum supported the differentiation and migration of epithelial cells better than plasma.The biochemical character of serum eyedrops is determined by the parameters chosen to produce the blood product. Plasma does not seem to offer an epitheliotrophic capacity equivalent to serum eyedrops. Their production should be optimized before any meaningful randomized controlled clinical trial can be attempted.
- Published
- 2004
32. [Methylated 2-aryl-1,4-naphtoquinone derivatives with diminished antioxidative activity]
- Author
-
G, Wurm and S, Schwandt
- Subjects
Magnetic Resonance Spectroscopy ,Chemical Phenomena ,Chemistry, Physical ,Photochemistry ,In Vitro Techniques ,Leukotriene B4 ,Lipids ,Antioxidants ,Structure-Activity Relationship ,Humans ,Indicators and Reagents ,Lipoxygenase Inhibitors ,Chromatography, High Pressure Liquid ,Granulocytes ,Naphthoquinones - Abstract
Methylated 2-aryl-1,4-naphtoquinone derivatives with diminished antioxidative activity 2-(3,5-Di-tert-butyl-4-hydroxyphenyl)-3-hydroxy-1,4-naphthoquinone (1) is a selective 5-lipoxygenase (5-LOX) inhibitor possessing high antioxidative activity (AOA). In order to study the question if this activity corresponds to the mechanism of the 5-LOX inhibition (redox type 5-LOX inhibitor) the analogues 57-66 and their 3-methoxy derivatives 47-56 of the reference compound 1 were synthezised. These compounds are mono- and dimethylated within the benzoid molecular moiety which were tested for their 5-LOX inhibiting activity using human granulocytes and for their AOA by a chemiluminometric method. The synthesis of the test compounds runs in the following manner: Diels-Alder reaction of 1,4-benzoquinone (2) with the buta-1,3-dienes 3-8, bromination of the 1,4-naphthoquinones 9-14, arylation with 2,6-di-tert-butylphenol and substitution of bromine of the aryl-bromonaphthoquinones 33-46 by methoxy and hydroxy functions. A key step is the cc separation of the regioisomeric mixtures 25/26-31/32. The most potent 5-LOX inhibitors (IC50 = 1-3 microM) possess methylfunctions in 5-/8-position and show markedly diminished AOA compared with 1. 5-LOX inhibition and AOA in this class of compounds hence are not positively correlated.
- Published
- 2003
33. [Pyrano[3,4-c]quinolines from 1-desaza--oxa-nifedipine]
- Author
-
K, Görlitzer, J, Trittmacher, P G, Jones, P, Frohberg, and G, Drutkowski
- Subjects
Models, Molecular ,Nifedipine ,Molecular Conformation ,Humans ,Indicators and Reagents ,Spectrophotometry, Ultraviolet ,Lipoxygenase Inhibitors ,In Vitro Techniques ,Crystallography, X-Ray ,Leukotriene B4 ,Chromatography, High Pressure Liquid - Abstract
Pyrano[3,4-c]quinolines from 1-desaza-1-oxa-nifedipine The reaction of the 1,5-diketone 1 with acetic anhydride/acetic acid in the presence of zinc chloride yields the 1-desaza-1-oxa-nifedipine 2 and the annulated lactone 3 as a by-product. The structures of 2 and 3 are confirmed by X-ray structure analysis. The pH-dependent reduction of the nitro group from 2 leads to the pyrano[3,4-c]quinolines 4Aa, b by ring closure. The cyclic hydroxamic acid 4Aa represents a weak, non-selective inhibitor of 5-, 12- and 15-lipoxygenase of human full-blood.
- Published
- 2003
34. [The hydroxam reaction of indometacin and acemetacin]
- Author
-
G, Zinner, J, Grünefeld, R, Gevensleben, and A, Grube
- Subjects
Anti-Inflammatory Agents, Non-Steroidal ,Indomethacin ,Indicators and Reagents ,Spectrophotometry, Ultraviolet ,Hydroxamic Acids ,Chromatography, High Pressure Liquid ,Edetic Acid ,Chelating Agents - Published
- 2003
35. [HbH disease--a rare differential diagnosis in a patient with anemia and abdominal pain]
- Author
-
Ursula, Fabry, Elisabeth, Kohne, Oliver, Galm, and Rainhardt, Osieka
- Subjects
Electrophoresis ,Male ,Anemia, Hemolytic ,Anemia, Hypochromic ,Genotype ,Middle Aged ,Prognosis ,Abdominal Pain ,Diagnosis, Differential ,Hemoglobins ,alpha-Thalassemia ,Mutation ,Humans ,Chromatography, High Pressure Liquid - Abstract
A 45-year-old Vietnamese male was admitted to hospital with severe hypochromic anemia and acute abdominal pain. The peripheral blood smear showed extreme anisocytosis and poikilocytosis as well as teardrops and target cells. Hemoglobin electrophoresis and brilliant cresyl blue staining revealed hemoglobin H (HbH) disease with an infection-associated hemolytic crisis.In the diagnostic workup of hemolytic and hypochromic anemia, HbH disease as a special type of alpha-thalassemia should be considered early. In patients from Eastern Asia with a mean corpuscular hemoglobin (MCH)25 pg, hemoglobin analysis should be performed in order to avoid unnecessary diagnostic procedures. The prognosis of HbH disease is generally favorable, and symptomatic treatment is only recommended during hemolytic crises in association with, e.g., infections or pregnancy.
- Published
- 2003
36. [Conjugation reactions of ciprofibrate with human and laboratory animals]
- Author
-
Herbert, Oelschläger, Dieter, Müller, Karl-Heinz, Hellwich, Sieglinde, Ueberall, Andreas, Seeling, Heike, Machts, Brit, Hofmann, and Reinhild, Glöckner
- Subjects
Hydrolysis ,Fibric Acids ,Mass Spectrometry ,Rats ,Clofibric Acid ,Feces ,Glucuronides ,Drug Stability ,Glucuronic Acid ,Animals ,Humans ,Amino Acids ,Biotransformation ,Chromatography, High Pressure Liquid ,Hypolipidemic Agents - Abstract
An open problem of the lipid lowering agent ciprofibrate (rac-2-[4-(2,2-dichlorocyclopropyl)-phenoxy]-2-methylpropanoic acid, CAS 52214-84-3) is its metabolism concerning the conjugation with amino acids and glucuronic acid. It could be solved by syntheses of the needed reference compounds--unknown up to now--and administration of ciprofibrate to volunteers and rats. Unexpectedly the conjugation compounds with amino acids are stable in vitro and in metabolism. There was no evidence for any conjugation reaction with amino acids by investigating samples of urine and faeces. On the contrary the urine of humans contains 90-97% of beta-O-acylglucuronide, whereas rat urine shows only 10% of the calculated amount.
- Published
- 2003
37. [Spectroscopic and chromatographic studies on photochemical isomerism of alpha, beta-diunsaturated ketones]
- Author
-
M, Schleuder, F, Am Ali, and H H, Otto
- Subjects
Chromatography, Gas ,Magnetic Resonance Spectroscopy ,Isomerism ,Light ,Spectrophotometry, Infrared ,Photochemistry ,Spectrophotometry, Ultraviolet ,Ketones ,Chromatography, High Pressure Liquid ,Mass Spectrometry - Abstract
Spectroscopic (UV, IR, NMR, MS) and chromatographic (HPLC, GC) investigations show for alpha,beta-diunsaturated ketones with one double bond fixed in a cyclohexene-, furan- or thiophene ring in most examples a photochemical Z/E-isomerization in solution by the influence of light. Investigations of conformers by IR and NMR however are not influenced during usual operations and light protection is not nessessary.
- Published
- 2003
38. [The example: St. John's wort. Manufacturing and quality aspects of plant extracts]
- Author
-
Frauke, Gaedcke
- Subjects
Chromatography, Gas ,Drug Industry ,Plant Extracts ,Chromatography, High Pressure Liquid ,Hypericum ,Phytotherapy - Published
- 2003
39. [Absorption of L-lysine diatrizoate from the gastrointestinal tract: the influence of surgery, inflammation and neoplasia]
- Author
-
W, Golder, G, Dietz, K, Rittinghaus, P, Weinberg, and M, Jarosch
- Subjects
Adult ,Aged, 80 and over ,Inflammation ,Male ,Lysine ,Age Factors ,Administration, Oral ,Contrast Media ,Middle Aged ,Diatrizoate ,Radiography ,Sex Factors ,Intestinal Absorption ,Administration, Rectal ,Data Interpretation, Statistical ,Abdomen ,Intestinal Neoplasms ,Humans ,Female ,Prospective Studies ,Digestive System ,Chromatography, High Pressure Liquid ,Aged - Abstract
To ascertain whether the absorption of L-lysine diatrizoate, a sodium-free salt of the contrast-giving diatrizoic acid, from the gastrointestinal tract is increased by surgery, inflammation or neoplasia.Using contrast medium containing L-lysine diatrizoate for intestinal opacification, this prospective study compared 32 radiographic examinations of the upper gastrointestinal tract with 52 radiographic examination of the lower gastrointestinal tract. In blood samples taken from the patients immediately after the radiographic examinations, the concentration of diatrizoic acid was determined by high pressure liquid chromatography. The results were correlated with sex, age, surgical history and any evidence of inflammatory or neoplastic diseases.The serum diatrizoic acid concentration in patients after oral administration was 3.62 (95% CI, 2.86 - 10.17) microg/ml. The titer was lower in patients who had undergone abdominal surgery than in patients without surgery. Serum diatrizoic acid concentration in patients after rectal administration was 0.30 (95% CI, 0.13 - 0.60) microg/ml. The titer was significantly higher (p0.05) in patients suffering from inflammatory conditions or neoplasms than in the other patients.The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper than from the lower gastrointestinal tract. Absorption is not increased after abdominal surgery. However, inflammatory conditions and neoplasms of the large bowel increase the uptake of contrast medium from the intestine.
- Published
- 2003
40. [Pulmonary plasma catecholamine levels and pulmonary hypertension in congenital heart disease]
- Author
-
W, Knirsch, M, Eiselt, J, Nürnberg, N A, Haas, F, Berger, I, Dähnert, F, Uhlemann, and P E, Lange
- Subjects
Adult ,Heart Defects, Congenital ,Heart Septal Defects, Ventricular ,Male ,Pulmonary Circulation ,Adolescent ,Epinephrine ,Hypertension, Pulmonary ,Infant ,Middle Aged ,Heart Septal Defects, Atrial ,Norepinephrine ,Catecholamines ,Child, Preschool ,Humans ,Female ,Vascular Resistance ,Child ,Chromatography, High Pressure Liquid ,Aged - Abstract
Plasma catecholamines may play a role in the pathogenesis of pulmonary hypertension in congenital heart disease with increased pulmonary blood flow. At cardiac catheterization, blood samples were obtained before and after passage of the lung in patients with congenital heart disease with normal pulmonary blood flow (n=39), elevated pulmonary blood flow with normal pulmonary pressure and normal pulmonary vascular resistance (PVR) in patients with atrial septal defect (ASD) (n=57) or ventricular septal defect (VSD) (n=12), and increased pulmonary blood flow, pressure and vascular resistance in patients with ASD, VSD or both (n=22), or in patients with primary pulmonary hypertension (n=4). Plasma catecholamines were determined by reversed phase high performance liquid chromatography and electrochemical detection (HPLC-ECD). In patients with elevated PVR elevated norepinephrine levels (NE) were observed. In contrast, epinephrine levels (E) were not associated with the development of pulmonary hypertension. Patients with primary pulmonary hypertension had the highest levels of NE while patients with associated Down's syndrome had significantly lower epinephrine levels. Pulmonary plasma norepinephrine levels are increased in patients with elevated pulmonary vascular resistance. Whether this phenomena is the cause or sequalae of pulmonary hypertension needs further examination. In the future, plasma catecholamines may serve as a diagnostic feature or may result in further therapeutic options.
- Published
- 2002
41. [Postmortem distribution of sertraline and desmethylsertraline in a fatality]
- Author
-
Frank, Musshoff, Sibylle, Banaschak, and Burkhard, Madea
- Subjects
Adult ,Dose-Response Relationship, Drug ,Cause of Death ,Poisoning ,Postmortem Changes ,Sertraline ,Humans ,Female ,Tissue Distribution ,Chromatography, High Pressure Liquid ,Gas Chromatography-Mass Spectrometry - Abstract
Sertraline (CAS 79617-96-2) is a relatively safe medication for patients suffering from depression. Data reporting the postmortal distribution of sertraline and desmethylsertraline remain rare as well as reports of risks of side effects following ingestion of the drug. In a case of a young woman found dead in her flat sertraline and desmethylsertraline were identified and quantified in body fluids and tissues by gas chromatography/mass spectrometry and high performance liquid chromatography with diode array detection after alkaline extraction. Sertraline and its desmethyl metabolite were found in the peripheral blood in levels of 0.15 mg/l and 0.20 mg/l, concentrations in liver and bile were markedly higher. By exclusion of other reasons for death a lethal sertraline intoxication was decided. Sertraline is suggested to possess a low inherent toxicity, however, a risk of side-effects which may occur in single cases even under moderate dosages should be considered.
- Published
- 2002
42. [Serum elimination of HES in moderately reduced renal function]
- Author
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Colombo T, Gassmayr Se, Sirtl C, Kröll W, Wolfgang Schimetta, List Wf, and W. Pölz
- Subjects
Male ,medicine.medical_specialty ,Plasma Substitutes ,Renal function ,Hydroxyethyl starch ,Critical Care and Intensive Care Medicine ,Kidney Function Tests ,Hydroxyethyl Starch Derivatives ,chemistry.chemical_compound ,Pharmacokinetics ,Internal medicine ,medicine ,Humans ,Chromatography, High Pressure Liquid ,Aged ,Creatinine ,business.industry ,Significant difference ,General Medicine ,medicine.disease ,Molecular Weight ,Anesthesiology and Pain Medicine ,Elevated serum creatinine ,Endocrinology ,chemistry ,Emergency Medicine ,Female ,Kidney Diseases ,business ,Perfusion ,medicine.drug ,Kidney disease ,Half-Life - Abstract
Objective: If or at which conditions hydroxyethyl starch (HES) is administerable in presence of reduced renal function, is a question still to be answered. The aim of this study was to give hints, whether a moderately reduced renal function (creatinine concentrations around 2,0mg/dl) induces clinically relevant changes in pharmacokinetics of HES 200/0.5. Methods: Each of 8 test persons with elevated serum creatinine concentration (1.6-2.9 mg/dl - group H) and 6 test persons with normal serum creatinine concentration (0.7-1.1 mg/dl - group N) were infused with 500 ml of 10% HES 200/0.5 within 30 minutes. Concentrations of creatinine and HES were measured before starting the infusion, immediately after the end of the infusion as well as 30 minutes, 60 minutes, 3 hours, 6 hours and 24 hours later. Additionally in group H also the mean values of the intravital molecular mass of HES (weight average molecular weight Mw and number average molecular weight Mn) were assessed. HES concentrations were quantified by the hexokinase method. HES molecular mass spectrum was analyzed by an HPLC method. The mean dwelling time served as an indicator for HES pharmacokinetics. Results: The serum creatinine concentrations remained stable within the observation period. The HES serum concentrations were comparable between the two groups at any examination. Immediately after the end of the infusion, the HES serum concentration reached a maximum of 17.5 mg/ml (group H) and 17.4 mg/ml (group N), 24 hours later HES serum concentration ranged between 1.4 and 2.0 mg/ml (group H) respectively between 1.1 and 2.8 mg/ml (group N). The calculation for the mean dwelling time resulted in 5.0 hours for group H and 4.5 hours for group N (median values) without significant difference between the groups (p = 0.147). At the end of the observation period, the mean values of the molecular weight Mw and Mn-measured in group H-reached the closest convergence (Mw: 71,000 Dalton; Mn: 58,000 Dalton; Mw/Mn: 1.32 - median values). Conclusion: Compensated renal failure with serum creatine concentrations up to 2.9 mg/dl does not significantly delay the serum elimination of HES 200/0.5. All findings support the opinion that a peri-operative volume substitution with HES 200/0.5 can be applied in patients suffering from moderately reduced renal function in the same way as in patients without any renal impairment.
- Published
- 2002
43. [Development of an HPLC method for the diagnosis of heparin-induced thrombocytopenia]
- Author
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U. Budde, S. Walch, J. Harenberg, M. Ödel, S. Koch, and H. Schmidt-Gayk
- Subjects
Chemistry ,Heparin ,Anticoagulants ,General Medicine ,Pharmacology ,Critical Care and Intensive Care Medicine ,medicine.disease ,Thrombocytopenia ,Anesthesiology and Pain Medicine ,Heparin-induced thrombocytopenia ,Emergency Medicine ,medicine ,Humans ,Hplc method ,Chromatography, High Pressure Liquid - Published
- 2002
44. [Pharmacokinetics of cephalexin from two oral formulations in dogs]
- Author
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A M, Ehinger and M, Kietzmann
- Subjects
Male ,Cephalexin ,Dogs ,Metabolic Clearance Rate ,Administration, Oral ,Animals ,Biological Availability ,Female ,Chromatography, High Pressure Liquid ,Cephalosporins - Abstract
Six beagle dogs were treated with cephalexin-monohydrate from 2 oral formulations (Rilexine tablets and Cefaseptin dragees, respectively) in a dosage of 25 mg/kg and plasma concentrations of cephalexin were measured over 8 hours. After solid phase extraction of the samples, cephalexin was determined by high pressure liquid chromatography with UV detection. After administration, Cephalexin was absorbed rapidly and mean maximum plasma concentrations of 30.9 and 27.9 micrograms/ml, respectively, were acquired after approximately 1.6 hours. Minimal inhibitory concentrations ofor = 6.25 micrograms/ml for in vitro sensitive bacteria were maintained for about 5 hours. Cephalexin from the tested preparations reached a mean area under the plasma concentration-time curve of 115.3 and 102.4 micrograms.h/ml, respectively. The plasma concentration decreased rapidly with a mean half life period of 1.4 hours in average. The other calculated pharmacokinetic parameters were also in the area of the data for dogs stated in the literature. There was no clear difference in the pharmacokinetics of both products, especially the bioavailability. Furthermore, both formulations were well tolerated clinically.
- Published
- 2002
45. [Relative bioavailability of diclofenac after a single administration of a new multiple-unit formulation of enteric-coated pellets]
- Author
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K, Walter and A, von Nieciecki
- Subjects
Adult ,Male ,Cross-Over Studies ,Diclofenac ,Double-Blind Method ,Anti-Inflammatory Agents ,Biological Availability ,Humans ,Steroids ,Tablets, Enteric-Coated ,Chromatography, High Pressure Liquid - Abstract
The relative bioavailability of diclofenac (CAS 15307-86-5) was investigated after a single administration of a multiple-unit formulation containing 75 mg diclofenac sodium in enteric-coated pellets (A) in comparison to an enteric-coated tablet with 50 mg diclofenac sodium (B), a capsule containing 140 mg diclofenac resinate (C) and a dispersible tablet containing 46.5 mg diclofenac acid (D). The study was carried out in a four-way crossover design in 16 healthy male volunteers. Serum concentrations of diclofenac were determined with a validated and specific HPLC-method. After dose normalisation, a mean relative bioavailability of 99% (B), 142% (C) and 116% (D) was determined for the pellet formulation. According to the corresponding 90%-confidence interval, bioequivalence for the extent of bioavailability of the test formulation can be concluded compared to the enteric-coated tablet. In comparison to the formulations C and D, the test formulation showed an increased extent of bioavailability. Further differences in pharmacokinetics were observed for the rate-dependent parameters. For the test formulation, the highest mean maximum serum concentration (1595 ng/ml) was measured with a corresponding tmax of 0.8 h. For the reference formulations, mean peak serum concentrations of 1285 ng/ml after 2.0 h (B), 370 ng/ml after 1.8 h (C) and 735 ng/ml after 1.9 h (D) were observed. Despite the enteric-coating of the pellets, a short lagtime of 0.4 h was determined for the test formulation. For the other rapid-release formulation (D), the lagtime was of a similar magnitude (0.3 h), while drug release and absorption from the enteric-coated tablet and the diclofenac resinate capsule were delayed (1.8 and 0.7 h, respectively). Due to the rapid and high bioavailability of diclofenac, the multiple-unit formulation fulfills the prerequisites for the oral treatment of acute painful conditions when prompt analgesic and anti-inflammatory efficacy is desired.
- Published
- 2001
46. [Synthesis and pharmacologic action of chiral fomocaine ((4-[2-methyl-3-(morpholin-4-yl)propyl)benzyl)-phenyl-ether and (4-(1-methyl-3-(morpholin-4-yl)propyl]benzyl)-phenyl-ether). 13. Synthesis of new compounds with local anesthetic action]
- Author
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H, Oelschläger, P, Glassl, A, Seeling, J, Wange, M, Listing, and B, Jung
- Subjects
Spectrophotometry, Infrared ,Swine ,Morpholines ,Phenyl Ethers ,Stereoisomerism ,In Vitro Techniques ,Mass Spectrometry ,Biopharmaceutics ,Lethal Dose 50 ,Microsomes, Liver ,Animals ,Indicators and Reagents ,Chromatography, Thin Layer ,Anesthetics, Local ,Chromatography, High Pressure Liquid ,Ethers - Abstract
The syntheses of two chiral fomocaines namely rac ((4-[2-methyl-3-(morpholin-4-yl)propyl]-benzyl)-phenyl-ether (O/G 3) and rac (4-[1-methyl-3-(morpholin-4-yl)propyl]benzyl)-phenyl-ether) (O/G 5) are reported. These compounds are part of a new research program concerning the relation between chirality and local anaesthetic activity in the group of fomocaines. The yield over five steps is in the range of 9% (O/G 3) up to 19.2% (O/G 5). The racemates were resoluted via the diastereomeric salts formed with (+)- or (-)-camphersulfonic acid. The chromatographic resolution in analytical scale is successful using a Daicel OD-column. The enantiomers are stable. The surface anaesthesia of the racemates as well as of the enantiomeres is weaker in comparison with fomocaine. The rate of tissue irritation is higher. The LD50 (mouse i.v.) is in the range between 290-390 mg/kg, while fomocaine shows a LD50 value of 175 mg/kg.
- Published
- 2001
47. [The content of biogenic amines in canned fish from the Turkish market]
- Author
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N, Erkan, N, Helle, and O, Ozden
- Subjects
Quality Control ,Biogenic Amines ,Turkey ,Food Preservation ,Fish Products ,Fishes ,Animals ,Chromatography, High Pressure Liquid - Abstract
This paper describes the determination of biogenic amines in a number of canned fish of the Turkish market by means of HPLC. Over all 39 cans of sardine, tuna, sardel, mackerel, pelamide and trout were tested. The determination of agmatine, cadaverine, histamine, putrescine and tyramine was performed by HPLC with post column derivatization with ortho-phthaldialdehyde. Four samples contained higher amounts of biogenic amines (three sardine samples contained more than 1000 mg/kg histamine) while all other samples were acceptable. These results demonstrate the need of instrumental analyses in the quality control system of Turkish producers of canned fish. The quality of the products at least of some producers has to be improved, e.g. by cooperation between the official food control and the quality assurance system of the producers.
- Published
- 2001
48. [Detection of levamisole and ivermectin in organ samples from a dead collie]
- Author
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H, Meiser, H W, Hagedorn, M, Majzoub, and R, Schulz
- Subjects
Ivermectin ,Antinematodal Agents ,Muscles ,Drug Synergism ,Sensitivity and Specificity ,Gas Chromatography-Mass Spectrometry ,Drug Hypersensitivity ,Dogs ,Fatal Outcome ,Adipose Tissue ,Levamisole ,Liver ,Animals ,Female ,Dog Diseases ,Chromatography, High Pressure Liquid - Abstract
A collie, known for its breed-dependent adverse reaction to ivermectin, was without any clinical signs. The dog was prophylactically treated with 3 mg/kg KG (s.c.) of levamisole. Within 15 minutes, the dog showed convulsions, vomitus, and dyspnea, and perished 2.5 hours after injection of the drugs. The pathological findings were not informative as to the cause of death, and with regard to the adverse reactions, additional application of ivermectin was not excluded. Therefore, organ samples were submitted for toxicological analysis of both levamisole and ivermectin. For detection of levamisole and ivermectin, modified GC/MS and HPLC procedures were developed. Concentrations up to 535 micrograms levamisole and up to 26 ng ivermectin were found per g tissue. Both analytical methods are sensitive enough to detect these drugs after application of low doses. This study elucidates that combination of low-dosed ivermectin and levamisole is no recommendable means against adverse effects of ivermectin, with respect to collies. Moreover, the synergistic effects of ivermectin and levamisole suggests the same drug incompatibility in other dog breeds and animal species.
- Published
- 2001
49. [The iodine supply of newborns. Comparison of iodine absorption and iodine excretion of mother and child]
- Author
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C, Roth, J, Meller, S, Bobrzik, H, Thal, W, Becker, D, Kulenkampff, M, Lakomek, and H, Zappel
- Subjects
Breast Feeding ,Milk, Human ,Pregnancy ,Germany ,Dietary Supplements ,Infant, Newborn ,Humans ,Female ,Infant Food ,Chromatography, High Pressure Liquid ,Bottle Feeding ,Iodine - Abstract
Since 1989 the use of iodized salt has been allowed in Germany, additional supplementation with iodide tablets has been recommended during pregnancy and lactation. This study was undertaken to clarify whether the iodine intake of neonates and young infants improved since then.In the first part of the study the urinary iodine excretion of 52 newborns and their mothers in 1998 was compared to data of similar studies 1983 in the area of Göttingen and 1982 in the areas of Heidelberg and Rothenburg, Germany. All these are geographically low-iodine areas. In the second part the iodine supply of infants in 1998-1999 under feeding with mother's milk or formulas in 1998 and 1999 was obtained by measuring iodide concentrations in urine and milk using a high pressure liquid chromatography (HPLC) method.45% of pregnant women were without iodide supplementation in 1998. In 1998 the median urinary iodide concentration during the first week of life was 4.3 micrograms/dl, which was more than twice that found in 1983 (1.75 micrograms/dl). Infants feeding by mother's milk without maternal iodine supplementation or by semi-elementary diet had the lowest urinary iodine excretion, whereas significantly higher values were measured when feeding formulas for term or preterm infants.The iodine intake of newborns has markedly improved during 15 years. The WHO criterias for adequate iodine supply (TSH5 microU/ml and urinary iodine/ = 10 micrograms/dl) were only partly fulfilled in Göttingen indicating that a mild iodine deficiency still exists with the risk of iodine deficiency disorders.
- Published
- 2001
50. [Pharmacokinetics of kanamycin after subcutaneous and intravenous administration in dogs]
- Author
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A, Calvo Wieland, A M, Ehinger, M, Kietzmann, and I, Nolte
- Subjects
Dogs ,Kanamycin ,Metabolic Clearance Rate ,Injections, Subcutaneous ,Ovariectomy ,Injections, Intravenous ,Animals ,Biological Availability ,Female ,Chromatography, High Pressure Liquid - Abstract
Six beagle dogs were treated with kanamycin subcutaneously or intravenously in a dosage of 5 mg/kg. The plasma kanamycin concentration was measured over 24 hours by high pressure liquid chromatography with UV detection after derivatization and solid phase extraction. After subcutaneous application, kanamycin was absorbed quickly, and maximum plasma levels of 18.9 micrograms/ml in average after ca. 1 hour were measured. With complete systemic availability, the minimal inhibitory concentration of 4 micrograms/ml was maintained for 4 hours. After subcutaneous administration, kanamycin was terminally eliminated with a mean half life period of 2 hours.
- Published
- 2001
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