Search results for "stimulant"
showing 10 items of 126 documents
Validation of a semi-physiological model for caffeine in healthy subjects and cirrhotic patients.
2015
The objective of this paper was to validate a previously developed semi physiological model to simulate bioequivalence trials of drug products. The aim of the model was to ascertain whether the measurement of the metabolite concentration-time profiles would provide any additional information in bioequivalence studies (Fernandez-Teruel et al., 2009a,b; Navarro-Fontestad et al., 2010). The semi-physiological model implemented in NONMEM VI was used to simulate caffeine and its main metabolite plasma levels using caffeine parameters from bibliography. Data from 3 bioequivalence studies in healthy subjects at 3 different doses (100, 175 and 400mg of caffeine) and one study in cirrhotic patients …
Limiting immunopathology: Interaction between carotenoids and enzymatic antioxidant defences.
2015
The release of reactive oxygen and nitrogen species (ROS and RNS) during the inflammatory response generates damages to host tissues, referred to as immunopathology, and is an important factor in ecological immunology. The integrated antioxidant system, comprising endogenous antioxidant enzymes (e.g. superoxide dismutase SOD, and catalase CAT) and dietary antioxidants (e.g. carotenoids), helps to cope with immune-mediated oxidative stress. Crustaceans store large amounts of dietary carotenoids for yet unclear reasons. While being immunostimulants and antioxidants, the interaction of these pigments with antioxidant enzymes remains unclear. Here, we tested the interaction between dietary supp…
Substance-use disorder in high-functioning autism: clinical and neurocognitive insights from two case reports.
2014
Background Low prevalence of substance-use disorder has been reported in adults with autism. However, on a superficial level, adults with high-functioning autism (HFA) display a ‘normal’ façade when they drink alcohol, which may explain why their alcohol dependency is not better diagnosed. Case presentation Here, we report two cases of HFA adults who use alcohol and psychostimulants to cope with their anxiety and improve their cognitive abilities and social skills. We analyze how neurocognitive traits associated with HFA may be potential triggers for substance-use disorder. Conclusion Better identification of autism and its cognitive impairments, which may be vulnerability traits for develo…
Self-Regulation Therapy to Reproduce Drug Effects:A Suggestion Technique to Change Personality and theDRD3Gene Expression
2013
This study proposes a strategy, based on self-regulation therapy, to change personality and its biological substrate, the DRD3 gene expression. It has been demonstrated that acute doses of stimulating drugs, like methylphenidate, are able to change personality and the expression of certain genes in the short term. On the other hand, self-regulation therapy has been proven to reproduce the effects of drugs. Thus, it is feasible to hope that self-regulation therapy is equally effective as methylphenidate in changing personality and the gene expression. This is a preliminary study with a single-case experimental design with replication in which 2 subjects participated. The results and potentia…
Effects of bupropion, alone or coadministered with nicotine, on social behavior in mice
2008
Bupropion, administered alone or combined with nicotine, is presently used to treat nicotine dependence. Despite experimental evidence of the complex behavioral actions of this drug, there have been little data reported about its effects on social behavior. Our main aim was to investigate the effects of acute administration of bupropion, alone or plus nicotine, on social interaction in mice. OF1 group-housed male mice were confronted in a neutral cage with an anosmic opponent during a 10 minutes encounter. Time allocated to body care and digging was reduced by administration of bupropion (40 mg/kg) both when administered alone and with nicotine (1 and 0.5 mg/kg). The lowest dose of bupropio…
Dose-Related Concentrations of Neuroactive/Psychoactive Drugs Expected in Blood of Children and Adolescents
2020
PURPOSE Therapeutic drug monitoring is highly recommended for children and adolescents treated with neurotropic/psychotropic drugs. For interpretation of therapeutic drug monitoring results, drug concentrations (C/D) expected in a "normal" population are helpful to identify pharmacokinetic abnormalities or nonadherence. Using dose-related concentration (DRC) factors obtained from pharmacokinetic data, C/D ranges expected under steady state can be easily calculated by multiplication of DRC by the daily dose. DRC factors, however, are defined only for adults so far. Therefore, it was the aim of this study to estimate DRC factors for children and adolescents and compare them with those of adul…
Impaired oral absorption of methylphenidate after Roux-en-Y gastric bypass
2017
The anatomic and physiologic changes in the gastrointestinal (GI) tract after bariatric surgery may significantly affect the pharmacokinetics of medications taken by the patients for various reasons. Unfortunately, there is little information regarding changes in drug absorption after bariatric surgeries, limiting the ability of medical professionals to produce clear recommendations on what changes should be made to the formulations and dosing regimens of drugs after bariatric surgery. In this article, we report and analyze a case of 52-year-old male patient with morbid obesity and attention-deficit/hyperactivity disorder (ADHD) who experienced lack of methylphenidate efficacy after Roux en…
Changing the General Factor of Personality and the c-fos Gene Expression with Methylphenidate and Self-Regulation Therapy
2012
[EN] A deepening in the biological nature of the general factor of personality (GFP) is suggested: the activation level of the stress system is here represented by the gene expression of c-fos. The results of a single case experimental design are reported. A model of four coupled differential equations that explains the human personality dynamics as a consequence of a single stimulant drug intake has been fitted to psychological and biological experimental data. The stimulant-drug conditioning and its adaptation to the considered mathematical model is also studied for both kinds of measures. The dynamics of the cfos expression presents a similar pattern to the dynamics of the psychological …
Role of acute social stress in the rewarding effects of MDMA in adolescent mice
2021
Drug use among adolescents is a serious problem in our society, as some individuals develop dependence and addiction. MDMA/Esctasy is one of the most typically used substances by this age group. It is well known that environmental factors can alter the rewarding properties of drugs and the propensity to drug-related disorders. In this sense, exposure to social stress induces long-term effects in mice, enhancing the rewarding effects of MDMA in the conditioned place preference (CPP) paradigm. On the other hand, previous research has not provided conclusive results regarding the short-term effects of social defeat on MDMA reward in adolescent animals, probably due to the use of very low or ve…
Effect of adolescent exposure to MDMA and cocaine on acquisition and reinstatement of morphine-induce CPP
2007
It is well known that an elevated percentage of ecstasy users also consume cocaine. Recently, it has been reported that a high frequency of heroin smokers first consumed heroin under the effects of ecstasy with the hope of reducing the stimulant effects of the latter drug. The aim of the present study was to evaluate the effect of exposure to MDMA and cocaine during adolescence on morphine-induced conditioned place preference (CPP) and reinstatement in adulthood. In the first experiment, adolescent mice were exposed to six injections of MDMA and three weeks later their response to the reinforcing properties of 40 mg/kg of morphine was evaluated using the CPP paradigm. All the treatment grou…