G Geisslinger

Goethe-Universität Frankfurt am Main, Frankfurt am Main, Hesse, Germany

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Publications (155)483.14 Total impact

  • Article: Simultaneous and sensitive LC-MS/MS determination of tetrahydrocannabinol and metabolites in human plasma.
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    ABSTRACT: Cannabis is not only a widely used illicit drug but also a substance which can be used in pharmacological therapy because of its analgesic, antiemetic, and antispasmodic properties. A very rapid and sensitive method for determination of ∆(9)-tetrahydrocannabinol (THC), the principal active component of cannabis, and two of its phase I metabolites in plasma has been developed and validated. After solid-phase extraction of plasma (0.2 mL), the clean extracts were analyzed by tandem mass spectrometry after a 5-min liquid chromatographic separation. The linear calibration ranges were from 0.05 to 30 ng mL(-1) for THC and 11-nor-∆(9)-carboxy-tetrahydrocannabinol (THC-COOH) and from 0.2 to 30 ng mL(-1) for ∆(9)-(11-OH)-tetrahydrocannabinol (11-OH-THC). Imprecision and inaccuracy were always below 7 and 12 % (expressed as relative standard deviation and relative error), respectively. The method has been successfully applied to determination of the three analytes in plasma obtained from healthy volunteers after oral administration of 20 mg dronabinol.
    Analytical and Bioanalytical Chemistry 10/2012; · 3.78 Impact Factor
  • Article: Comparative clinical effects of hydromorphone and morphine: a meta-analysis.
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    ABSTRACT: We have conducted a meta-analysis of the clinical effects of morphine and hydromorphone to compare their benefit in analgesia. Embase and Medline were searched with an end-date of June 2009 for randomized, controlled trials or observational studies that addressed comparative analgesic and side-effects or particular side-effects. Two researchers independently identified included studies and extracted the data. Estimates of opioid effects were combined by using a random-effects model. Meta-analysis of eight studies suggested that hydromorphone (494 patients) provides slightly better (P=0.012) clinical analgesia than morphine (510 patients). The effect-size was small (Cohen's d=0.266) and disappeared when one study was removed, although the advantage of hydromorphone was more evident in studies of better quality (Jadad's rating). Side-effects were similar, for example, nausea (P=0.383, nine studies, 456 patients receiving hydromorphone and 460 morphine); vomiting (P=0.306, six studies, 246 patients receiving hydromorphone and 239 morphine); or itching (P=0.249, eight studies, 405 patients receiving hydromorphone, 410 morphine). This suggests some advantage of hydromorphone over morphine for analgesia. Additional potential clinical pharmacological advantages with regard to side-effects, such as safety in renal failure or during acute analgesia titration, are based on limited evidence and require substantiation by further studies.
    BJA British Journal of Anaesthesia 09/2011; 107(3):319-28. · 4.24 Impact Factor
  • Article: A pirinixic acid derivative (LP105) inhibits murine 5-lipoxygenase activity and attenuates vascular remodelling in a murine model of aortic aneurysm.
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    ABSTRACT: BACKGROUND AND PURPOSE Arachidonic acid derivatives play a central role in inflammation processes. Arachidonic acid is metabolized by several enzymes, particularly cyclooxygenases (COX), 5-lipoxygenase (5-LOX) and microsomal prostaglandin E-synthase-1 (mPGES-1) to pro-inflammatory mediators. EXPERIMENTAL APPROACH We determined the effect of LP105, a pirinixic acid derivative which acts as inhibitor of 5-LOX, COX and mPGES-1, on aortic aneurysm development in mice and on 5-LOX activity in murine monocytes. KEY RESULTS In a monocyte cell line (RAW264.7), LP105 inhibited 5-LOX in whole cells (IC(50) : 1-3 µM) and in supernatants (IC(50) : ∼10 µM). Oral administration of LP105 to mice resulted in therapeutic tissue and plasma levels. Aortic aneurysms were induced in ApoE(-/-) mice by angiotensin II (AngII) and LP105 (5 mg·day(-1) per animal) was co-administered to a subgroup. Compared with animals receiving AngII alone, the LP105+AngII group showed a lower heart rate, a trend towards reduced heart to body weight ratio but similar hypertensive responses. AngII alone significantly increased aortic weight and diameter but co-treatment with LP105+AngII prevented these changes. LC/MS-MS studies revealed increased 15-hydroxytetraenoic acid (15-HETE) and 14,15-epoxyeicosatrienoic acid (14,15-EET) plasma levels in LP105-treated animals. In the murine kidney, mRNAs of EET-generating or metabolizing enzymes and of 5-LOX and 15-LOX were unaffected by LP105. LP105 also did not inhibit the EET-metabolizing soluble epoxide hydrolase. CONCLUSIONS AND IMPLICATIONS LP105 was a potent inhibitor of monocyte 5-LOX and reduced AngII-induced vascular remodelling in mice. A shift of arachidonic acid metabolism to the protective EET pathway may contribute to the beneficial effects of LP105.
    British Journal of Pharmacology 03/2011; 163(8):1721-32. · 4.41 Impact Factor
  • Article: The role NADPH Oxidase 4 derived reactive oxygen species in pain signaling
    Naunyn-Schmiedebergs Archives of Pharmacology. 01/2011; 383:29-29.
  • Article: 5-Lipoxygenase inhibitors induce potent anti-proliferative and cytotoxic effects in human tumour cells independently of suppression of 5-lipoxygenase activity.
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    ABSTRACT: Certain 5-lipoxygenase (5-LO) inhibitors exhibit anti-carcinogenic activities against 5-LO overexpressing tumour types and cultured tumour cells. It has been proposed therefore that 5-LO products significantly contribute to tumour cell proliferation. To date, the relationship between the inhibitory mechanisms of 5-LO inhibitors, which vary widely, and tumour cell viability has not been evaluated. This study addresses the anti-proliferative and cytotoxic potency of a number of 5-LO inhibitors with different inhibitory mechanisms in 5-LO-positive and 5-LO-negative tumour cells. Cell viability was measured by the WST-1 assay; cell proliferation was assessed using the bromodeoxyuridine (BrdU) incorporation assay. Cell death was analysed by annexin V staining, Western blot analysis of PARP (poly ADP-ribose polymerase) cleavage and a cytotoxicity assay. 5-LO product formation was quantified by a 5-LO activity assay. The common 5-LO inhibitors AA-861, Rev-5901 and MK-886 induced cytotoxic and anti-proliferative effects in 5-LO-positive Capan-2 pancreatic cancer cells; BWA4C and CJ-13,610 only caused anti-proliferative effects, while zileuton failed to impair cell viability. Moreover, the concentrations of the 5-LO inhibitors required to induce anti-proliferation and cytotoxicity highly exceeded those for suppression of 5-LO. Supplementation with mitogenic 5-LO products failed to protect Capan-2 cells from the effects of 5-LO inhibitors. Finally, the cytotoxic and anti-proliferative 5-LO inhibitors also potently reduced the viability of 5-LO-deficient tumour cell lines (HeLa, Panc-1 and U937). Certain 5-LO inhibitors cause cytotoxic and anti-proliferative effects independently of suppression of 5-LO activity. Thus, the role of 5-LO overexpression in tumour cell viability remains unclear and requires further elucidation.
    British Journal of Pharmacology 10/2010; 161(4):936-49. · 4.41 Impact Factor
  • Article: Bedside-to-bench pharmacology: a complementary concept to translational pharmacology.
    J Lötsch, G Geisslinger
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    ABSTRACT: Translational pharmacology is contemporary; it efficiently covers the progress of research from cellular and animal experiments to the patient. Its logical reasoning is deductive by definition. Abductive reasoning in pharmacological research is often placed second. Although straightforward processes might suit some organizational models, a reasoning process preferring only one direction may sacrifice opportunities. Both directions of reasoning may lead to independent yet comparable or even identical successes, and it is only by using both together that one gains the full benefit of human intellectual resources.
    Clinical Pharmacology &#38 Therapeutics 06/2010; 87(6):647-9. · 6.04 Impact Factor
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    Article: Selective antagonism of opioid-induced ventilatory depression by an ampakine molecule in humans without loss of opioid analgesia.
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    ABSTRACT: Ventilatory depression is a significant risk associated with the use of opioids. We assessed whether opioid-induced ventilatory depression can be selectively antagonized by an ampakine without reduction of analgesia. In 16 healthy men, after a single oral dose of 1,500 mg of the ampakine CX717, a target concentration of 100 ng/ml alfentanil decreased the respiratory frequency by only 2.9 +/- 33.4% as compared with 25.6 +/- 27.9% during placebo coadministration (P < 0.01).Blood oxygenation and the ventilatory response to hypercapnic challenge also showed significantly smaller decreases with CX717 than with placebo. In contrast, CX717 did not affect alfentanil-induced analgesia in either electrical or heat-based experimental models of pain. Both ventilatory depression and analgesia were reversed with 1.6 mg of naloxone. These results support the use of ampakines as selective antidotes in humans to counter opioid-induced ventilatory depression without affecting opioid-mediated analgesia.
    Clinical Pharmacology &#38 Therapeutics 11/2009; 87(2):204-11. · 6.04 Impact Factor
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    Article: Prostaglandin D2 produced by hematopoietic prostaglandin D synthase contributes to LPS-induced fever.
    W Gao, A Schmidtko, I Wobst, R Lu, C Angioni, G Geisslinger
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    ABSTRACT: A large body of evidence has implicated prostaglandin E(2) (PGE(2)) in fever production. However, the role of PGD(2) in this context is only poorly understood. We therefore determined by LC-MS/MS analyses the content of PGD(2) and PGE(2) in cerebrospinal fluid (CSF), plasma and lungs of rats over 5 hours after fever induction by intraperitoneal injection of lipopolysaccharide (LPS, 50 microg/kg). Both PGD(2) and PGE(2) were detected in CSF, plasma and lungs of saline-treated control animals. The injection of LPS evoked fever and an increase of PGE(2) in the CSF, while the CSF content of PGD(2) was not significantly altered. However, both PGE(2) and PGD(2) levels were elevated in plasma and lungs after LPS injection. Interestingly, pretreatment with a novel selective inhibitor of hematopoietic prostaglandin D synthase (H-PGDS), EDJ300520 (10-40 mg/kg p.o.), selectively and dose-dependently prevented the LPS-induced increase of PGD(2) in plasma and lungs but did not affect the PGE(2) content. Most remarkably, EDJ300520 pretreatment led to an hypothermic response after LPS injection during the first 3 h and prevented fever induction. These data indicate that PGD(2) produced peripherally by H-PGDS essentially contributes to LPS-induced fever.
    Journal of physiology and pharmacology: an official journal of the Polish Physiological Society 07/2009; 60(2):145-50. · 2.27 Impact Factor
  • Article: The consequence of concomitantly present functional genetic variants for the identification of functional genotype-phenotype associations in pain.
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    ABSTRACT: Genetics-based personalized approaches to pain management have received a setback because of the nonreproducibility of functional genetic associations such as the pain-modulatory effect of the catechol-O-methyl transferase (COMT) gene 472G>A single-nucleotide polymorphism. Given that many of the pain-relevant genetic variants are common (allelic frequencies of 10-50%), we hypothesized that a major reason for difficulties in reproducing demonstrations of genetic influences on pain is the concomitant presence in a single individual of several functional genetic polymorphisms that act as confounders.
    Clinical Pharmacology &#38 Therapeutics 06/2008; 85(1):25-30. · 6.04 Impact Factor
  • Article: Differential opioid action on sensory and affective cerebral pain processing.
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    ABSTRACT: Low doses of morphine, the most commonly used opioid analgesic, have been shown to significantly reduce the affective but not the sensory intensive dimension of pain. This suggests differential dose-response relationships of opioid analgesia on the sensory and affective components of pain. We investigated the effects of different alfentanil plasma concentration levels (0, 19.6+/-2.7, 47.2+/-7.6, and 76.6+/-11.3 ng/ml) on pain-related brain activation achieved by short pulses of gaseous CO(2) delivered to the nasal mucosa, using functional magnetic resonance imaging (fMRI) on a 3.0 T MRI scanner in 16 non-carriers and 9 homozygous carriers of the mu-opioid receptor gene variant OPRM1 118A>G. Increasing opioid concentrations had differential effects in brain regions processing the sensory and affective dimensions of pain. In brain regions associated with the processing of the sensory intensity of pain (primary and secondary somatosensory cortices, posterior insular cortex), activation decreased linearly in relation to alfentanil concentrations, which was significantly less pronounced in OPRM1 118G carriers. In contrast, in brain regions known to process the affective dimension of pain (parahippocampal gyrus, amygdala, anterior insula), pain-related activation disappeared at the lowest alfentanil dose, without genotype differences.
    Clinical Pharmacology &#38 Therapeutics 04/2008; 83(4):577-88. · 6.04 Impact Factor
  • Article: Effects of selective COX-2 inhibition on prostanoids and platelet physiology in young healthy volunteers.
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    ABSTRACT: Selective inhibitors of cyclooxygenase-2 (COX-2) called coxibs, are effective anti-inflammatory and analgesic drugs. Recently, these drugs were associated with an increased risk for myocardial infarction and atherothrombotic events. The hypothesis of thromboxane-prostacyclin imbalance has been preferred to explain these unwanted effects. We studied the effects of 14 days intake of rofecoxib (25 mg q.d.), celecoxib (200 mg b.i.d.), naproxen (500 mg b.i.d.) and placebo in a randomized, blinded, placebo-controlled study in young healthy volunteers (median age 25-30 years, each group n = 10). We assessed prostanoid metabolite excretion (PGE-M, TXB(2), 6-keto-PGF(1alpha), 11-dehydro-TXB(2), 2,3-dinor-TXB(2), and dinor-6-keto-PGF(1alpha)), the expression of platelet activation markers (CD62P, PAC-1, fibrinogen), platelet-leukocyte formation, the endogenous thrombin potential, platelet cAMP content and plasma thrombomodulin level. Naproxen suppressed biosynthesis of PGE-M, prostacyclin metabolites and thromboxane metabolites and thrombomodulin levels. In contrast, both coxibs had an inhibitory effect only on PGE-M, 6-keto-PGF(1alpha), and on dinor-6-keto-PGF(1alpha), whereas TXB(2), 2,3-dinor-TXB(2) and 11-dehydro-TXB(2) excretion were unaffected. None of the coxibs exerted significant effects on the expression of platelet activation markers, cAMP generation, platelet-leukocyte formation, or on thrombomodulin plasma levels. Interestingly, platelet TXB(2) release during aggregation was enhanced after coxib treatment following arachidonic acid or collagen stimulation. In young healthy volunteers coxibs inhibit systemic PGE(2) and PGI(2) synthesis. Platelet function and expression of platelet aggregation markers are not affected; however, coxibs can stimulate TXB(2) release from activated platelets. Combined decrease in vasodilatory PGE(2) and PGI(2) together with increased TXA(2) in proaggregatory conditions may contribute to coxib side effects.
    Journal of Thrombosis and Haemostasis 01/2008; 5(12):2376-85. · 5.73 Impact Factor
  • Article: Inhibition of cyclooxygenases by dipyrone.
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    ABSTRACT: Dipyrone is a potent analgesic drug that has been demonstrated to inhibit cyclooxygenase (COX). In contrast to classical COX-inhibitors, such as aspirin-like drugs, dipyrone has no anti-inflammatory effect and a low gastrointestinal toxicity, indicating a different mode of action. Here, we aimed to investigate the effects of dipyrone on COX. The four major metabolites of dipyrone, including the two pharmacologically active metabolites, 4-methyl-amino-antipyrine (MAA) and amino-antipyrine (AA), were used to characterise their binding to COX and haem as well as their effects on the biochemical properties of COX. Mass spectrometry, UV and visible photometry were used to study binding and prostaglandin production. Levels of anti-oxidant enzymes were assessed by Western blotting. The pharmacologically active metabolites of dipyrone, MAA and AA, did not inhibit COX activity in vitro like classical COX inhibitors, but instead redirected the prostaglandin synthesis, ruling out inhibition of COX through binding to its active site. We found that MAA and AA formed stable complexes with haem and reacted with hydrogen peroxide in presence of haem, ferrous ions (Fe(2+)) or COX. Moreover, MAA reduced Fe(3+) to Fe(2+) and accordingly increased lipid peroxidation and the expression of anti-oxidant enzymes in cultured cells and in vivo. Our data suggest that the pharmacologically active metabolites of dipyrone inhibit COX activity by sequestering radicals which initiate the catalytic activity of this enzyme or through the reduction of the oxidative states of the COX protein.
    British Journal of Pharmacology 07/2007; 151(4):494-503. · 4.41 Impact Factor
  • Article: The partial 5-hydroxytryptamine1A receptor agonist buspirone does not antagonize morphine-induced respiratory depression in humans.
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    ABSTRACT: Based on experiments in rats, serotonin receptor 5-hydroxytryptamine (5-HT)(1A) agonists have been proposed as a potential therapeutic strategy for the selective treatment of opioid-induced respiratory depression. We investigated the clinical applicability of this principle in healthy volunteers. Twelve subjects received 0.43 mg/kg morphine (30 mg for 70 kg body weight) administered intravenously (i.v.) over approximately 2 h. At the start of the morphine infusion, they received in a randomized, double-blind cross-over design 60 mg p.o. buspirone or placebo. Respiratory depression (hypercapnic challenge) and pain (electrical stimuli: 5 Hz sinus 0-20 mA; chemical stimuli: 200 ms gaseous CO(2) pulses applied to the nasal mucosa) were assessed at baseline, at the end of the morphine infusion, and a third time after antagonizing the opioid effects by i.v. administration of 2 mg naloxone. The linear relationship between the minute ventilation and the CO(2) concentration in the inspired air of 1.07+/-0.27 l/mm Hg CO(2) at baseline conditions became shallower (0.45+/-0.23 l/mm Hg CO(2)) after morphine administration (P<0.001), indicating respiratory depression, which was significantly reversed by naloxone (0.95+/-0.43 l/mm Hg CO(2); P=0.001). Co-administration of buspirone had no effect on morphine-induced respiratory depression (slope 0.45+/-0.23 l/mm Hg CO(2) under morphine plus placebo versus 0.38+/-0.25 l/mm Hg CO(2) under morphine plus buspirone; P=0.7). Significant morphine-induced analgesia was observed in both pain models and was reversed by naloxone but unaffected by buspirone. Buspirone significantly increased the nausea induced by morphine (P=0.011). Oral co-administration of a high dose of the clinically available 5-HT(1A) agonist buspirone cannot be advised as a remedy for opioid-induced respiratory depression. This is indicated by its lack of anti-respiratory depressive effects and by the buspirone-associated increase of morphine-induced nausea.
    Clinical Pharmacology &#38 Therapeutics 01/2007; 81(1):59-68. · 6.04 Impact Factor
  • Article: Differential opioid action on sensory and affective cerebral pain processing assessed by functional magnetic resonance imaging
    Basic & Clinical Pharmacology & Toxicology. 01/2007; 101(5):367-367.
  • Article: [Are polymorphisms in the mu-opioid receptor important for opioid therapy?].
    J Lötsch, R Freynhagen, G Geisslinger
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    ABSTRACT: Polymorphisms in the mu-opioid receptor gene may potentially alter the clinical effects of opioid analgesics. A common mu-opioid receptor polymorphism occurring at an allelic frequency of 12% decreases the potency of opioid analgesics in humans. Interestingly, in carriers of this mutation, it appears to be possible to reach analgesia by increasing the opioid dose but side effects appear to occur less often despite the higher opioid dose. This suggests a broadened therapeutic range of the opioids. Other mutations of the mu-opioid receptor, for example three mutations within the third intracellular loop of the receptor, impair receptor signaling, but they are too rare to greatly affect pain therapy or have not yet been investigated in the context of pain therapy.
    Der Schmerz 11/2005; 19(5):378-82, 384-5. · 0.88 Impact Factor
  • Article: [Fundamental principles of clinical trials].
    C Skarke, G Geisslinger
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    ABSTRACT: Medical conduct relies on the efficacy and tolerability of a given pharmacotherapy. On the basis of an experimental comparison of different treatment options, a clinical trial provides the foundation for an evidence-based medicine that complies with state-of-the-art scientific practice. The quality of the data assessment determines the clinical relevance of the study results. Clinical trials are classified into Phases I-IV to ensure the development of an effective and safe pharmaceutical. The investigator is responsible for being experienced in the relevant area of expertise, for conducting the study according to the investigational plan, and for complying with ethical guidelines and drug safety.
    Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz 05/2005; 48(4):401-7. · 0.66 Impact Factor
  • Article: Grundlagen der klinischen Arzneimittelprüfung
    C. Skarke, G. Geisslinger
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    ABSTRACT: Die Pharmakotherapie sttzt sich auf die nachgewiesene Wirksamkeit und Vertrglichkeit. Die klinische Prfung schafft mit dem experimentellen Vergleich unterschiedlicher Therapieoptionen die Grundlage fr eine evidenzbasierte Medizin, die den aktuellen wissenschaftlichen Ansprchen gerecht wird. Die Qualitt der Studiendurchfhrung entscheidet ber die klinische Relevanz der Studienergebnisse. Die Entwicklung eines wirksamen und sicheren Arzneimittels verluft in mehreren Phasen (I–IV) der Arzneimittelprfung. Dem Prfer werden verbindliche Verantwortlichkeiten aufgetragen, die im Wesentlichen aus der Expertise im Indikationsgebiet, der prfplankonformen Durchfhrung und aus der Einhaltung ethischer Grundlagen bestehen.Medical conduct relies on the efficacy and tolerability of a given pharmacotherapy. On the basis of an experimental comparison of different treatment options, a clinical trial provides the foundation for an evidence-based medicine that complies with state-of-the-art scientific practice. The quality of the data assessment determines the clinical relevance of the study results. Clinical trials are classified into Phases I–IV to ensure the development of an effective and safe pharmaceutical. The investigator is responsible for being experienced in the relevant area of expertise, for conducting the study according to the investigational plan, and for complying with ethical guidelines and drug safety.
    Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz 03/2005; 48(4):401-407. · 0.66 Impact Factor
  • Article: Comparison of two screening methods for in-house genotyping in clinical pharmacology units.
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    ABSTRACT: Two genetic screening methods, the fluorescence resonance energy transfer (FRET) technique on the LightCycler and the real-time pyrophosphate detection technique on the Pyrosequencer have been compared with regard to their usefulness as screening methods for subject recruitment in clinical studies in pharmacology units. Two SNPs of possible clinical relevance were selected, namely the 118A>G SNP of the OPRM1 gene and the 3435C>T SNP of the ABCB1 gene. Genotypes diagnosed using conventional sequencing served as control. The allelic frequency of the mutated 118G allele of the OPRM1 gene was 12.7% and that of the mutated 3435T allele of the ABCB1 gene was 50.7%. All results obtained with the Pyrosequencer were in accord with those obtained using conventional sequencing. With the LightCycler, an incorrect genotype was assigned to 1 of the 130 DNA samples corresponding to an error rate of 0.8%. Although both methods were found suitable for rapid SNP detection, Pyrosequencing was the preferred method since it provides the nucleotide sequence directly thus facilitating interpretation.
    International journal of clinical pharmacology and therapeutics 02/2005; 43(1):17-22. · 1.18 Impact Factor
  • Article: Single-step identification of all length polymorphisms in the UGT1A1 gene promoter.
    C Skarke, S Grösch, G Geisslinger, J Lötsch
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    ABSTRACT: To provide a sensitive genetic screening method for rapid identification of all known length polymorphisms in the promoter region of the uridine 5'-diphosphoglucose glucuronosyltransferase (UGT) 1A1 gene comprising (TA)5, (TA)7 and (TA)8 repeats as opposed to the non-mutated (TA)6 allele. The UGT1A1 promoter genotype was assessed in 115 subjects by means of a newly developed pyrosequencing method. PCR-generated DNA templates of heterozygous (TA)5 and (TA)7 carriers were cloned into a TOPO TA vector and verified by sequencing. In addition, a (TA)8 segment was produced by cloning to demonstrate the ability of the method to detect this mutation. All length polymorphisms of the UGT1A1 promoter described in the literature were clearly identified. Fifteen subjects had Gilbert's syndrome with elevated serum bilirubin associated with a homozygous (TA)7TAA/(TA)7TAA genotype. Two subjects with the rare genotypes (TA)5TAA/(TA)6TAA and (TA)5TAA/(TA)7TAA were found, where only the latter one displayed elevated serum bilirubin levels. Allelic frequencies were 0.9%, 66.1% and 33% for the (TA)5TAA, (TA)6TAA and (TA)7TAA allele, respectively. Our method enables reliable genetic single-step screening for all known length polymorphisms in the UGT1A1 gene promoter that cause Gilbert's syndrome. This facilitates pharmacogenetic-guided dosing of drugs with known toxicity metabolized by UGT1A1.
    International journal of clinical pharmacology and therapeutics 04/2004; 42(3):133-8. · 1.18 Impact Factor
  • Article: Programming of a flexible computer simulation to visualize pharmacokinetic-pharmacodynamic models.
    J Lötsch, G Kobal, G Geisslinger
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    ABSTRACT: Teaching pharmacokinetic-pharmacodynamic (PK/PD) models can be made more effective using computer simulations. We propose the programming of educational PK or PK/PD computer simulations as an alternative to the use of pre-built simulation software. This approach has the advantage of adaptability to non-standard or complicated PK or PK/PD models. Simplicity of the programming procedure was achieved by selecting the LabVIEW programming environment. An intuitive user interface to visualize the time courses of drug concentrations or effects can be obtained with pre-built elements. The environment uses a wiring analogy that resembles electrical circuit diagrams rather than abstract programming code. The goal of high interactivity of the simulation was attained by allowing the program to run in continuously repeating loops. This makes the program behave flexibly to the user input. The programming is described with the aid of a 2-compartment PK simulation. Examples of more sophisticated simulation programs are also given where the PK/PD simulation shows drug input, concentrations in plasma, and at effect site and the effects themselves as a function of time. A multi-compartmental model of morphine, including metabolite kinetics and effects is also included. The programs are available for download from the World Wide Web at http:// www. klinik.uni-frankfurt.de/zpharm/klin/ PKPDsimulation/content.html. For pharmacokineticists who only program occasionally, there is the possibility of building the computer simulation, together with the flexible interactive simulation algorithm for clinical pharmacological teaching in the field of PK/PD models.
    International journal of clinical pharmacology and therapeutics 02/2004; 42(1):15-22. · 1.18 Impact Factor

Institutions

  • 1999–2012
    • Goethe-Universität Frankfurt am Main
      • Zentrum der Pharmakologie
      Frankfurt am Main, Hesse, Germany
  • 2000–2005
    • Institut für klinische Pharmakologie
      Stuttgart, Baden-Wuerttemberg, Germany
    • Stanford University
      • Department of Anesthesia
      Palo Alto, CA, USA
  • 1989–2001
    • Friedrich-Alexander Universität Erlangen-Nürnberg
      • • Department of Anaesthesiology
      • • Department of Experimental and Clinical Pharmacology and Toxicology
      Erlangen, Bavaria, Germany
  • 1989–2000
    • Universitätsklinikum Erlangen
      Erlangen, Bavaria, Germany
  • 1998–1999
    • Hadassah Medical Center
      • Department of Medicine
      Jerusalem, Jerusalem District, Israel
    • Hebrew University of Jerusalem
      Jerusalem, Jerusalem District, Israel
  • 1996
    • Karl-Franzens-Universität Graz
      Graz, Styria, Austria
    • University of New South Wales
      Kensington, New South Wales, Australia
  • 1992–1995
    • St. Vincent's Hospital Sydney
      • Clinical Pharmacology and Toxicology
      Sydney, New South Wales, Australia
    • Max-Planck-Institut für biophysikalische Chemie
      Göttingen, Lower Saxony, Germany
  • 1994
    • Ruhr-Universität Bochum
      Bochum, North Rhine-Westphalia, Germany