35 research outputs found
A noninterventional study evaluating the effectiveness of rotigotine and levodopa combination therapy in younger versus older patients with Parkinson\u27s disease
Background: PD0013 was a 6-month non-interventional study in clinical-practice comparing effectiveness and tolerability of rotigotine+levodopa in younger (<70years) vs. older (≥70years) Parkinson’s disease (PD) patients.Methods: Patients previously received levodopa for ≥6-months as monotherapy or in combination with another dopamine-agonist (DA). Primary variable: Unified PD Rating Scale (UPDRS) Part-II change from baseline to end-of-observation-period (EOP).Results: 91 younger/99 older patients started rotigotine; 68 younger/62 older patients completed the study. Most switched from levodopa+another DA. Addition of rotigotine as first DA was more common in older patients (20.2% vs.15.4%). Mean\ub1SD rotigotine-exposure: 6.1\ub13.4mg/24h younger vs. 4.9\ub12.4mg/24h older. Eleven patients changed levodopa dose during the study.At EOP, improvement in mean UPDRS-II was greater in younger patients (p=0.0289). UPDRS-II responder-rate (≥20% decrease in UPDRS-II score) was higher in younger patients (42.3% vs. 25.9%). Improvement across age-groups was similar on PD Sleep Scale-2 and Clinical Global Impressions-Improvement Scale. Adverse-drug-reactions (ADRs), and discontinuations because of ADRs, were more common among older patients. There were no new safety-signals.Conclusions: Despite low rotigotine doses, when added to levodopa or switched from levodopa+another DA, rotigotine led to greater improvement in UPDRS-II in younger patients (<70years). Assessment of individual patient data revealed clinically-meaningful improvements in UPDRS-II in both age-groups
Influence of the rate of hepatic portal vein infusion on hexobarbital pharmacokinetics in the rat
Pharmacokinetic parameters of hexobarbital were estimated in rats after hepatic portal infusion of a 10-mg dose. Infusion during 10 min resulted in an area under the blood concentration-time curve (AUC) of 556 +/- 83 micrograms.min/ml and a clearance of 83 +/- 13 ml/min.kg, whereas infusion of the same dose during 40 min resulted in values of 272 +/- 36 micrograms.min/ml and 169 +/- 30 ml/min.kg, respectively (mean values +/- SD, n = 3). Infusion during 15 and 20 min provided intermediate values. The decrease of the AUC and the increase of the blood clearance of hexobarbital following decreasing infusion rates clearly indicate nonlinear pharmacokinetics related to the hepatic inflow concentration of hexobarbital
Correlation between the in vivo metabolism of hexobarbital and antipyrine in rats with a portacaval shunt
Influence of 9-hydroxyellipticine and 3-methylcholanthrene treatment on antipyrine metabolite formation in rats in vivo
The influence of pretreatment of rats with 9-hydroxyellipticine and 3-methylcholanthrene on different enzymes of the hepatic mixed-function oxidase system were studied using antipyrine as model compound. Antipyrine half-lives and clearances were estimated in blood, and the metabolite profile was determined in urine. 3-Methylcholanthrene treatment resulted in an increase in antipyrine clearance from 17 to 75 ml/min per kg. Partial clearance of formation of 4-hydroxyantipyrine was selectively increased from 3.9 to 28.2 ml/min kg, whereas clearance of 3-hydroxymethylantipyrine was decreased from 3.2 to 1.2 ml/min per kg. Norantipyrine formation was increased from 2.7 to 7.2 ml/min per kg, while 4,4'-dihydroxyantipyrine formation was unchanged. 9-Hydroxyellipticine treatment resulted in no change in the total clearance, and only the clearance of 4,4'-dihydroxyantipyrine was decreased, from 2.5 to 1.5 ml/min per kg. After pretreatment with 3-methylcholanthrene, 9-hydroxyellipticine treatment resulted in a selective decrease in the clearances of 4-hydroxyantipyrine, from 28.2 to 15.8 ml/min per kg, and of 4,4'-hydroxyantipyrine, from 3.8 to 1.6 ml/min per kg. From these results it is concluded, that 9-hydroxyellipticine is a selective inhibitor of the activity of some of the cytochrome P-450s involved in antipyrine metabolism, though this inhibition does not effect all of these enzymes, nor is it restricted to polycyclic hydrocarbon-induced activity. These results further substantiate the value of antipyrine as a model substrate, for they indicate that the formation of all four metabolites of antipyrine in rats is mediated by different (iso-)enzymes
Disposition of hexobarbital enantiomers in the rat
The enantiomers of hexobarbital (HB), designated as (+)-HB and (-)-HB, were administered orally to separate groups of rats. Blood concentration-time curves of the parent compounds and the metabolites 3'-hydroxyhexobarbital (OH-HB) and 3'-ketohexobarbital (K-HB) were determined, as well as the cumulative urinary excretion of unconjugated OH-HB, K-HB, and 1,5-dimethylbarbituric acid (DMBA). The t1/2,(+)-HB was 13.4 +/- 0.8 min, and the t1/2,(-)-HB was slightly longer, 16.7 +/- 0.6 min (mean +/- SEM, N = 6). The intrinsic clearance values, CLint,(+)-HB and CLint,(-)-HB, were 2947 +/- 358 and 411 +/- 65 ml min-1 kg-1, respectively. The extraction ratios (E) were 0.94 for (+)-HB and 0.68 for (-)-HB. The t1/2,OH-(+)-HB and t1/2,OH-(-)-HB as calculated from blood data, were nearly the same: 20.0 +/- 2.6 and 22.2 +/- 1.5 min, respectively. Such data could not be established for the K-HB metabolites, since the curves exhibited no clear elimination phase. DMBA was undetectable in blood. The cumulative excretion of the measured metabolites in 24-hr urine was 44.0 +/- 1.8% for (+)-HB and 78.9 +/- 2.9% for (-)-HB, which was predominantly due to a substantial difference in the percentage of K-HB excreted. It is concluded that, to apply HB as a model substrate to assess oxidative enzyme activity, the use of only (-)-HB should be preferred to (+)-HB or (+/-)-HB because of a lower intrinsic clearance and a more complete recovery of oxidized metabolites in urine
Correlation between the in vivo metabolism of hexobarbital and antipyrine in rats
Two model substrates for oxidative hepatic enzyme activity, viz. hexobarbital (HB) and antipyrine (AP), were given simultaneously to rats by the oral route of administration. Blood concentrations of HB and AP were measured simultaneously by a gas chromatographic method and the urinary excretion of six metabolites arising from AP and HB also was determined; norantipyrine, 4-hydroxyantipyrine and 3-hydroxymethylantipyrine (HMA) by high-performance liquid chromatography; 3'-hydroxyhexobarbital, 3'-ketohexobarbital and 1,5-dimethylbarbituric acid by gas-liquid chromatography. The apparent intrinsic clearances of HB (CL*int,HB) and AP (CL*int,AP) and the clearance for production of the various metabolites were correlated in an attempt to establish whether HB and AP have metabolic pathways mediated by the same or very similar forms of cytochrome P-450. In order to create broadly ranging and evenly distributed clearance values, 3-methylcholanthrene (3-MC)- and phenobarbital (PB) pretreated rats were employed in conjunction with a control group of untreated animals. CL*int,HB and CL*int,AP were both increased by PB pretreatment, but 3-MC-pretreatment increased CL*int,AP, whereas CL*int,HB was decreased. CL*int,HB and CL*int,AP were found to correlate poorly, when all groups were taken into consideration (r = -0.08). The formation of AP-metabolites was inducible by both PB and 3-MC, and good correlations between rates of formation of AP-metabolites and CL*int,HB and CL3'-hydroxy-HB + 3'-keto-HB were obtained.(ABSTRACT TRUNCATED AT 250 WORDS
Genotyping of European Toxoplasma gondii strains by a new high-resolution next-generation sequencing-based method.
PURPOSE
A new high-resolution next-generation sequencing (NGS)-based method was established to type closely related European type II Toxoplasma gondii strains.
METHODS
T. gondii field isolates were collected from different parts of Europe and assessed by whole genome sequencing (WGS). In comparison to ME49 (a type II reference strain), highly polymorphic regions (HPRs) were identified, showing a considerable number of single nucleotide polymorphisms (SNPs). After confirmation by Sanger sequencing, 18 HPRs were used to design a primer panel for multiplex PCR to establish a multilocus Ion AmpliSeq typing method. Toxoplasma gondii isolates and T. gondii present in clinical samples were typed with the new method. The sensitivity of the method was tested with serially diluted reference DNA samples.
RESULTS
Among type II specimens, the method could differentiate the same number of haplotypes as the reference standard, microsatellite (MS) typing. Passages of the same isolates and specimens originating from abortion outbreaks were identified as identical. In addition, seven different genotypes, two atypical and two recombinant specimens were clearly distinguished from each other by the method. Furthermore, almost all SNPs detected by the Ion AmpliSeq method corresponded to those expected based on WGS. By testing serially diluted DNA samples, the method exhibited a similar analytical sensitivity as MS typing.
CONCLUSION
The new method can distinguish different T. gondii genotypes and detect intra-genotype variability among European type II T. gondii strains. Furthermore, with WGS data additional target regions can be added to the method to potentially increase typing resolution
Genotyping of European Toxoplasma gondii strains by a new high-resolution next-generation sequencing-based method
Author contributions: MJ, PM, DH, RCB, MFE, PV, SCAC, LMO, PJ and GS contributed to the study conception and design. MJ, RCB, MFE, BK, RB, MGV, KS, NB, SSO, JS, WP, PK, WB, AM, LG, MLD, AB, FS, CS, MP, NS, AL, RKD, RT, HW, EDB, PV, SMC, LMO, PJ and GS provided key biological materials or data. Data collection and analysis were performed by MJ, PM, PV, SMC and GS with the support of DH and SCAL. The frst draft of the manuscript was written by MJ, GS and PM and all authors commented on previous versions of the manuscript. All authors read and approved the fnal manuscript.Purpose: A new high-resolution next-generation sequencing (NGS)-based method was established to type closely related European type II Toxoplasma gondii strains.
Methods: T. gondii field isolates were collected from different parts of Europe and assessed by whole genome sequencing (WGS). In comparison to ME49 (a type II reference strain), highly polymorphic regions (HPRs) were identified, showing a considerable number of single nucleotide polymorphisms (SNPs). After confirmation by Sanger sequencing, 18 HPRs were used to design a primer panel for multiplex PCR to establish a multilocus Ion AmpliSeq typing method. Toxoplasma gondii isolates and T. gondii present in clinical samples were typed with the new method. The sensitivity of the method was tested with serially diluted reference DNA samples.
Results: Among type II specimens, the method could differentiate the same number of haplotypes as the reference standard, microsatellite (MS) typing. Passages of the same isolates and specimens originating from abortion outbreaks were identified as identical. In addition, seven different genotypes, two atypical and two recombinant specimens were clearly distinguished from each other by the method. Furthermore, almost all SNPs detected by the Ion AmpliSeq method corresponded to those expected based on WGS. By testing serially diluted DNA samples, the method exhibited a similar analytical sensitivity as MS typing.
Conclusion: The new method can distinguish different T. gondii genotypes and detect intra-genotype variability among European type II T. gondii strains. Furthermore, with WGS data additional target regions can be added to the method to potentially increase typing resolution.European CommissionDepto. de Sanidad AnimalFac. de VeterinariaTRUEpu