Thesis (M.S.)--West Virginia University, 2004 / Title from document title page. Document formatted into pages; contains ix, 49 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 41-48).

Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains viii, 141 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

The Cytochrome P450 family of enzymes is responsible for the majority of Phase I metabolism, and has been identified as an important source of pharmacokinetic variation in therapeutic responses. CYP2C19 and CYP2D6, metabolising >35% of commonly prescribed medications, are two of the most important pharmacogenetic markers that have been studied with the aim of improving treatment response and reducing adverse drug reactions. The Food and Drug Administration (FDA) approved AmpliChip CYP450 Test (AmpliChip) was compared to a previously developed PCR-RFLP platform and a newly developed XLPCR+ Sequencing platform for the ability to identifying genotype and predicting phenotype for CYP2C19 and CYP2D6 respectively. The AmpliChip was found not to be genotypically comprehensive enough for evaluating CYP2C19 genotype, not robust enough for determining CYP2D6 genotype and inaccurate in predicting phenotype for both. The XLPCR+ Sequencing method identified three novel alleles and one sub-variant. Advances in online column-switching solid phase extraction generated a rapid and robust LCMS/ MS method for simultaneously quantifying the probe drugs omeprazole (CYP2C19 substrate), dextromethorphan (CYP2D6 substrate) and their metabolites. Antimodes were identified for phenotypic cut-offs which offered measured phenotype for comparison to predicted phenotype. Omeprazole metabolism by CYP2C19 correlated well with predicted phenotype in a demographically representative South African cohort. There are concerns regarding the use of omeprazole as a probe drug as participants predicted to be ultrarapid metabolisers for CYP2C19 had similar rates to extensive metabolisers. Regardless of this concern, decreased metabolism was assigned to the CYP2C19*15 for the first time. CYP2D6 predicted phenotype correlated very well with measured phenotype, validating the suitability of dextromethorphan use for measuring CYP2D6 metabolism. Substrate modified activity score using 0.5 to predict intermediate metabolisers fine-tuned the XLPCR+ Sequencing platform for phenotype prediction. This finding, along with observations in CYP2C19 metabolism of omeprazole, highlights the importance of substrate specific phenotype prediction strategies. Controversially, attempts to associate CYP2D6 phenotype prediction with risperidone-related adverse drug reactions has yielded conflicting results. The XL-PCR+Sequencing platform was able to discount this association by predicting a variety of metabolisers in a pilot cohort selected to be experiencing risperidone-related adverse drug reactions. The comprehensive capability of the XL-PCR+Sequencing allowed for the identification of an additional novel allele in this cohort. The data presented in thisthesis has provided insight into the relationship between predicted and measured phenotype for CYP2C19 and CYP2D6 in the South African population. The XL-PCR+Sequencing platform can be used for future research or can be applied to improve treatment outcome. The LC-MS/MS method developed could be used for future evaluations of predicted and measured phenotype with the ability to be adjusted for therapeutic drug monitoring. This thesis advances pharmacogenetics of CYP2C19 and CYP2D6 for use in the South African population. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Pharmacology / unrestricted

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A total of 146 Chinese patients with various degrees of hyperlipidaemia and high cardiovascular risk, suitable for treatment with rosuvastatin 10 mg daily and in whom it was possible to obtain baseline lipid profiles measured on no lipid lowering drug, were enrolled in to the study. The drug compliance was assessed by personal interview and 9 patients were excluded from the efficacy analysis because they stated their compliance was less than 80%. From the remaining 137 subjects, 62 had a clinical diagnosis of familial hypercholesterolaemia. Data for dietary intake were available in 121 of the 137 subjects. The average reduction in LDL-cholesterol in these subjects was 48.8 +/- 12.8% and as anticipated there was a wide range between individuals. The percentage reductions in LDL-cholesterol were significantly greater in the female than in the male subjects (-51.35 +/-10.89% vs. -46.38 +/-13.96%; p = 0.025), but this was no longer significant after adjustment for body weight. In patients with familial hypercholesterolaemia the absolute reductions in total cholesterol and LDL-cholesterol were significantly greater (p<0.001) than in those without familial hypercholesterolaemia, but the percentage reductions were not significantly different in the two groups. The increases in HDL-cholesterol and the decreases in triglycerides were significantly greater in the subjects with familial hypercholesterolaemia than in those without familial hypercholesterolaemia, both for the absolute changes and for the percentage changes. There were no significant effects on the percentage changes in lipids with rosuvastatin treatment due to age, measurements of body fatness, smoking or alcohol drinking status, or having hypertension or diabetes. / Polymorphisms in the CYP2D6 gene were analyzed and the subjects were divided into 4 groups as wild-type or extensive metabolisers, heterozygotes for CYP2D6*10 and wild-type, homozygotes for CYP2D6*10, and subjects with one allele for poor metaboliser status. The groups in this order would be expected to have decreasing activity of the CYP2D6 enzyme. There was a tendency for greater reduction in LDL-cholesterol in groups with lower CYP2D6 activity, most obvious in male subjects and this was significant in the patients with familial hypercholesterolaemia comparing the first 3 groups. The fourth group had a low number of subjects, which may have biased that result. In the subjects without familial hypercholesterolaemia, the % change in LDL-cholesterol was similar in all genotype groups, but the % reduction in triglycerides was numerically higher in the wild-type group than in groups with CYP2D6*10 alleles and the group with poor metaboliser status showed a lower % reduction. These differences were not significant and may be influenced by the baseline levels of triglycerides, which were not corrected for in this analysis. / The daily calorie intake and percentage of different macronutrient intake was obtained by using seven days food recall records. Dietary intake of most nutrients with higher in male than in female patients and was higher in the patients compared to gender-matched population data. Higher intake of most nutrients was associated with higher baseline triglyceride levels, but not LDL-cholesterol levels in all patients, and in lower HDL-cholesterol levels in the patients without familial hypercholesterolaemia. Higher intake of total calories was associated with less percentage reduction in LDL-cholesterol with rosuvastatin in the patients without familial hypercholesterolaemia and a similar non-significant tendency was seen with higher intake of total fat, saturated fat and cholesterol. / The study described in this thesis examined the role of the CYP2D6*10 polymorphism on the lipid response to rosuvastatin in addition to a number of phenotypic factors such as diet, gender, measures of obesity and other medical conditions. / These findings suggest that the CYP2D6 genotype may have some influence on the lipid response to rosuvastatin, but it appears to interact with other factors including, gender, diet and the presence of familial hypercholesterolaemia. (Abstract shortened by UMI.) / Lui, Siu Hung. / "February 2007." / Adviser: Brian Tomlinson. / Source: Dissertation Abstracts International, Volume: 69-01, Section: B, page: 0248. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 165-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

MUDr. Olga Matoušková - the dissertation theses The influence of individual genetic predisposition to the pharmacokinetics and pharmacodynamics of chosen opioids ABSTRACT Introduction: The aim of this thesis is to study the influence of polymorphism of CYP2D6 and MDR1 on the pharmacokinetics and pharmacodynamics of tramadol in healthy volunteers using measurement. A secondary objective is to evaluate these polymorphisms in relation to the analgesic efficacy and side effects of piritramide for acute postoperative pain. Materials and methods: In two prospective work studying the influence of genetic predisposition on the pharmacokinetic and pharmacodynamic parameters of tramadol, we included a total of 90 healthy volunteers. Clinical studies on opioid analgesia and influence of genetic predisposition to the pharmaco-therapeutic effects and side effects in patients with acute postoperative pain, we included a total of 161 patients with acute postoperative pain. Polymorphism genotyping CYP2D6 and MDR1 gene we performed PCR - RFLP analysis, to determine concentrations of tramadol and metabolite, we used gas and liquid chromatography and pharmacodynamic effects of opioids was evaluated by pupilometric measurement and visual analogue scale. Results and conclusion: Variability of the opioid effect is influenced by...

55 Abstract Frequency of selected genetic polymorphisms of cytochrome P450 in the Czech population and the influence of CYP2C9 genotype on the hypolipidemic effect of fluvastatin Introduction: One of the main factors of genetically determined variability in response of humans to administered drugs are differences in catalytic activity of metabolizing enzymes, which are caused mainly by genetic polymorphisms in cytochrom P450 family enzymes. This thesis consists of two parts and it is presented as a commentary to the original papers. The first aim was to investigate the frequency of functionally important variant alleles of three main isoenzymes of cytochrome P450 gene: CYP2D6, CYP2C9, CYP2C19, throughout the Czech population, predict the prevalence of poor metabolizer phenotypes, and then to compare the results to the data from other populations. Secondly, we analysed the correlation between the CYP2C9 genotype and cholesterol-lowering effect of fluvastatin in human hypercholesterolemic patients. Methods: Genotypes were determined by PCR-RFLP. The presence of alleles CYP2D6*1, *6, *5, *4, *3, and gene duplication was analysed in 233 healthy volunteers, CYP2C9*1, *2 and*3 in 254 subjects and CYP2C19*1, *2 and *2 in 218 subjects. Eighty seven patients on fluvastatin therapy, and 48 patients on monotherapy...

ABSTRACT/SUMMARY Background: The clinical efficacy of tamoxifen therapy may be modified by the drug-metabolizing enzymes and transporting molecules involved into the pharmacokinetics of tamoxifen. The aim of this study was to evaluate the association of CYP2D6, ABCB1 polymorhisms and comedication with efficacy and safety of tamoxifen treatment. Methods: Totally 258 women with hormonal positive breast carcinoma were retrospectively evaluated in relation to CYP2D6, ABCB1 polymorphisms and comedication. Results: CYP2D6 polymorphisms or co-medication affecting CYP2D6 activity demonstrated no statistically significant effect on the efficacy of tamoxifen therapy or adverse event incidence; there was only a trend towards shortening the time to event (TTE) in CYP2D6 poor metabolizers. ABCB1 polymorphism rs2032582 was not associated with clinical outcomes, while a trend towards an increase of TTE in variant allele carriers was noted. The ABCB1 polymorphism rs1045642 demonstrated statistical significance in premenopausal patients (p = 0.0012, HR 0.69 (95% CI 0.21 to 2.31), and its significant association was noted with gynaecological /vasomotor adverse events (p = 0.0221, HR = 1.0588), with no evidence of the influence on the incidence and onset of venous complications. Conclusions: Although this work did not show...

55 Abstract Frequency of selected genetic polymorphisms of cytochrome P450 in the Czech population and the influence of CYP2C9 genotype on the hypolipidemic effect of fluvastatin Introduction: One of the main factors of genetically determined variability in response of humans to administered drugs are differences in catalytic activity of metabolizing enzymes, which are caused mainly by genetic polymorphisms in cytochrom P450 family enzymes. This thesis consists of two parts and it is presented as a commentary to the original papers. The first aim was to investigate the frequency of functionally important variant alleles of three main isoenzymes of cytochrome P450 gene: CYP2D6, CYP2C9, CYP2C19, throughout the Czech population, predict the prevalence of poor metabolizer phenotypes, and then to compare the results to the data from other populations. Secondly, we analysed the correlation between the CYP2C9 genotype and cholesterol-lowering effect of fluvastatin in human hypercholesterolemic patients. Methods: Genotypes were determined by PCR-RFLP. The presence of alleles CYP2D6*1, *6, *5, *4, *3, and gene duplication was analysed in 233 healthy volunteers, CYP2C9*1, *2 and*3 in 254 subjects and CYP2C19*1, *2 and *2 in 218 subjects. Eighty seven patients on fluvastatin therapy, and 48 patients on monotherapy...

MUDr. Olga Matoušková - the dissertation theses The influence of individual genetic predisposition to the pharmacokinetics and pharmacodynamics of chosen opioids ABSTRACT Introduction: The aim of this thesis is to study the influence of polymorphism of CYP2D6 and MDR1 on the pharmacokinetics and pharmacodynamics of tramadol in healthy volunteers using measurement. A secondary objective is to evaluate these polymorphisms in relation to the analgesic efficacy and side effects of piritramide for acute postoperative pain. Materials and methods: In two prospective work studying the influence of genetic predisposition on the pharmacokinetic and pharmacodynamic parameters of tramadol, we included a total of 90 healthy volunteers. Clinical studies on opioid analgesia and influence of genetic predisposition to the pharmaco-therapeutic effects and side effects in patients with acute postoperative pain, we included a total of 161 patients with acute postoperative pain. Polymorphism genotyping CYP2D6 and MDR1 gene we performed PCR - RFLP analysis, to determine concentrations of tramadol and metabolite, we used gas and liquid chromatography and pharmacodynamic effects of opioids was evaluated by pupilometric measurement and visual analogue scale. Results and conclusion: Variability of the opioid effect is influenced by...