24 research outputs found

    Pharmacokinetic and pharmacogenetic determinants of the activity and toxicity of irinotecan in metastatic colorectal cancer patients

    Get PDF
    This study aims at establishing relationships between genetic and non-genetic factors of variation of the pharmacokinetics of irinotecan and its metabolites; and also at establishing relationships between the pharmacokinetic or metabolic parameters and the efficacy and toxicity of irinotecan. We included 49 patients treated for metastatic colorectal cancer with a combination of 5-fluorouracil and irinotecan; a polymorphism in the UGT1A1 gene (TA repeat in the TATA box) and one in the CES2 gene promoter (830C>G) were studied as potential markers for SN-38 glucuronidation and irinotecan activation, respectively; and the potential activity of CYP3A4 was estimated from cortisol biotransformation into 6β-hydroxycortisol. No pharmacokinetic parameter was directly predictive of clinical outcome or toxicity. The AUCs of three important metabolites of irinotecan, SN-38, SN-38 glucuronide and APC, were tentatively correlated with patients' pretreatment biological parameters related to drug metabolism (plasma creatinine, bilirubin and liver enzymes, and blood leukocytes). SN-38 AUC was significantly correlated with blood leukocytes number and SN-38G AUC was significantly correlated with plasma creatinine, whereas APC AUC was significantly correlated with plasma liver enzymes. The relative extent of irinotecan activation was inversely correlated with SN-38 glucuronidation. The TATA box polymorphism of UGT1A1 was significantly associated with plasma bilirubin levels and behaved as a significant predictor for neutropoenia. The level of cortisol 6β-hydroxylation predicted for the occurrence of diarrhoea. All these observations may improve the routine use of irinotecan in colorectal cancer patients. UGT1A1 genotyping plus cortisol 6β-hydroxylation determination could help to determine the optimal dose of irinotecan

    DNA methylation, the early-life social environment and behavioral disorders

    Get PDF
    One of the outstanding questions in behavioral disorders is untangling the complex relationship between nurture and nature. Although epidemiological data provide evidence that there is an interaction between genetics (nature) and the social and physical environments (nurture) in a spectrum of behavioral disorders, the main open question remains the mechanism. Emerging data support the hypothesis that DNA methylation, a covalent modification of the DNA molecule that is a component of its chemical structure, serves as an interface between the dynamic environment and the fixed genome. We propose that modulation of DNA methylation in response to environmental cues early in life serves as a mechanism of life-long genome adaptation. Under certain contexts, this adaptation can turn maladaptive resulting in behavioral disorders. This hypothesis has important implications on understanding, predicting, preventing, and treating behavioral disorders including autism that will be discussed

    The genetics of addiction—a translational perspective

    Get PDF
    Addictions are serious and common psychiatric disorders, and are among the leading contributors to preventable death. This selective review outlines and highlights the need for a multi-method translational approach to genetic studies of these important conditions, including both licit (alcohol, nicotine) and illicit (cannabis, cocaine, opiates) drug addictions and the behavioral addiction of disordered gambling. First, we review existing knowledge from twin studies that indicates both the substantial heritability of substance-specific addictions and the genetic overlap across addiction to different substances. Next, we discuss the limited number of candidate genes which have shown consistent replication, and the implications of emerging genomewide association findings for the genetic architecture of addictions. Finally, we review the utility of extensions to existing methods such as novel phenotyping, including the use of endophenotypes, biomarkers and neuroimaging outcomes; emerging methods for identifying alternative sources of genetic variation and accompanying statistical methodologies to interpret them; the role of gene-environment interplay; and importantly, the potential role of genetic variation in suggesting new alternatives for treatment of addictions

    Nonepileptic Seizure Outcome Varies by Type of Spell and Duration of Illness

    Full text link
    Purpose: To determine whether differences in clinical manifestations of psychogenic nonepileptic events are associated with differences in outcome and whether the length of illness before diagnosis correlates with outcome. Methods: We reviewed ictal videotapes and EEGs in 85 patients diagnosed with exclusively nonepileptic psychogenic seizures during inpatient CCTV-EEG monitoring at the University of Michigan between June 1994 and December 1996. They were classified into groups of similar ictal behaviors. Fifty-seven of these patients were available to respond to a follow-up telephone survey about their condition 2–4 years after discharge. We examined demographics, baseline EEG abnormalities, and outcome of treatment interventions. We also evaluated whether interventions were more likely to succeed if patients were diagnosed early in the course of the illness. Results: We found that the largest groups consisted of patients with motionless unresponsiveness (“catatonic,” n = 19) and asynchronous motor movements with impaired responsiveness (“thrashing,” n = 19). Infrequent signs included tremor, automatisms, subjective events with amnesia, and intermittent behaviors. There was a higher incidence of baseline EEG abnormalities in the thrashing group (31%) than in the catatonic group (0%). There was a higher incidence of complete remission of spells in the catatonic group (53%) than in the thrashing group (21%). Patients who had a more recent onset of seizures (most often within 1 year) were much more likely to have remission of spells after diagnosis. Conclusions: Classification of nonepileptic seizures is useful in predicting outcome and may be valuable in further investigation of this complex set of disorders.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65460/1/j.1528-1157.2000.tb04613.x.pd
    corecore