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Hair Analysis (hair + analysis)
Selected AbstractsHair Analysis Versus Conventional Methods of Drug Testing in Substance Abusers Seeking Organ TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010D. L. Haller As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt. [source] Ketamine use, cognition and psychological wellbeing: a comparison of frequent, infrequent and ex-users with polydrug and non-using controlsADDICTION, Issue 1 2009Celia J. A. Morgan ABSTRACT Introduction Preliminary research has indicated that recreational ketamine use may be associated with marked cognitive impairments and elevated psychopathological symptoms, although no study to date has determined how these are affected by differing frequencies of use or whether they are reversible on cessation of use. In this study we aimed to determine how variations in ketamine use and abstention from prior use affect neurocognitive function and psychological wellbeing. Method We assessed a total of 150 individuals: 30 frequent ketamine users, 30 infrequent ketamine users, 30 ex-ketamine users, 30 polydrug users and 30 controls who did not use illicit drugs. Cognitive tasks included spatial working memory, pattern recognition memory, the Stockings of Cambridge (a variant of the Tower of London task), simple vigilance and verbal and category fluency. Standardized questionnaires were used to assess psychological wellbeing. Hair analysis was used to verify group membership. Results Frequent ketamine users were impaired on spatial working memory, pattern recognition memory, Stockings of Cambridge and category fluency but exhibited preserved verbal fluency and prose recall. There were no differences in the performance of the infrequent ketamine users or ex-users compared to the other groups. Frequent users showed increased delusional, dissociative and schizotypal symptoms which were also evident to a lesser extent in infrequent and ex-users. Delusional symptoms correlated positively with the amount of ketamine used currently by the frequent users. Conclusions Frequent ketamine use is associated with impairments in working memory, episodic memory and aspects of executive function as well as reduced psychological wellbeing. ,Recreational' ketamine use does not appear to be associated with distinct cognitive impairments although increased levels of delusional and dissociative symptoms were observed. As no performance decrements were observed in the ex-ketamine users, it is possible that the cognitive impairments observed in the frequent ketamine group are reversible upon cessation of ketamine use, although delusional symptoms persist. [source] Hair Analysis Versus Conventional Methods of Drug Testing in Substance Abusers Seeking Organ TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010D. L. Haller As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt. [source] Ethyl glucuronide in hair.ADDICTION, Issue 6 2009A sensitive, specific marker of chronic heavy drinking ABSTRACT Aims This study aims to define a cut-off concentration for ethyl glucuronide in hair to determine if there was a history of heavy drinking. Settings Pavia, Italy. Participants We analysed hair samples from 98 volunteers among teetotallers, social drinkers and heavy drinkers, whose ethanol daily intake (EDI) was estimated by means of a written questionnaire. Measurements Ethyl glucuronide hair concentration (HEtG) was measured by liquid chromatography-tandem mass spectrometry (lower limit of quantification: 3 pg/mg) using a fully validated method. Findings The HEtG level providing the best compromise between sensitivity (0.92) and specificity (0.96) at detecting an EDI of 60 g or higher during the last 3 months was 27 pg/mg. None of the factors examined among those known to affect ethanol metabolism and/or the diagnostic power of other markers of ethanol use or hair analyses, including age, gender, body mass index, tobacco smoke, prevalent beverage, hair colour, cosmetic treatments and hygienic habits was found to influence marker performance significantly. However, the slight differences in HEtG performance observed for some factors (e.g. body mass index, smoke and hair treatments) require further studies on larger groups of individuals in order to assess their influence more precisely. Conclusions Our results confirm further that HEtG is a sensitive and specific marker of chronic heavy drinking. [source] Randomized controlled trial of dexamphetamine maintenance for the treatment of methamphetamine dependenceADDICTION, Issue 1 2010Marie Longo ABSTRACT Aim To investigate the safety and efficacy of once-daily supervised oral administration of sustained-release dexamphetamine in people dependent on methamphetamine. Design Randomized, double-blind, placebo-controlled trial. Participants Forty-nine methamphetamine-dependent drug users from Drug and Alcohol Services South Australia (DASSA) clinics. Intervention Participants were assigned randomly to receive up to 110 mg/day sustained-release dexamphetamine (n = 23) or placebo (n = 26) for a maximum of 12 weeks, with gradual reduction of the study medication over an additional 4 weeks. Medication was taken daily under pharmacist supervision. Measurements Primary outcome measures included treatment retention, measures of methamphetamine consumption (self-report and hair analysis), degree of methamphetamine dependence and severity of methamphetamine withdrawal. Hair samples were analysed for methamphetamine using liquid chromatography-mass spectrometry. Findings Treatment retention was significantly different between groups, with those who received dexamphetamine remaining in treatment for an average of 86.3 days compared with 48.6 days for those receiving placebo (P = 0.014). There were significant reductions in self-reported methamphetamine use between baseline and follow-up within each group (P < 0.0001), with a trend to a greater reduction among the dexamphetamine group (P = 0.086). Based on hair analysis, there was a significant decrease in methamphetamine concentration for both groups (P < 0.0001). At follow-up, degree of methamphetamine dependence was significantly lower in the dexamphetamine group (P = 0.042). Dexamphetamine maintenance was not associated with serious adverse events. Conclusions The results of this preliminary study have demonstrated that a maintenance pharmacotherapy programme of daily sustained-release amphetamine dispensing under pharmacist supervision is both feasible and safe. The increased retention in the dexamphetamine group, together with the general decreases in methamphetamine use, degree of dependence and withdrawal symptom severity, provide preliminary evidence that this may be an efficacious treatment option for methamphetamine dependence. [source] Time-of-flight secondary ion mass spectrometry analysis of the application of a cationic conditioner to ,clean' hairINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2004A. Harvey In this study the applicability of the surface-sensitive Time-of-flight secondary ion mass spectrometry (ToF-SIMS) technique to hair analysis and associated aqueous processing is evaluated. ToF-SIMS analysis of ,as received' human hair indicates the presence of silicones, anionic surfactants, and cationic conditioners, from previous treatments, on the fiber surface. Cleaning of the hair with SLS or SLES results in adsorption of the surfactants onto the fiber surface. In particular, the more non-polar surfactant components have greater substantivity for the fiber surface, as indicated by the relative increase in their ToF-SIMS intensity. Application of the Incroquat Behenyl 18-MEA conditioner to both ,virgin' and bleached hair results in the adsorption of the cationic C18, C20, C22, and C21 surfactant components onto the hair surface. The ToF-SIMS data indicate higher levels of conditioner on the bleached hair relative to the undamaged hair. [source] Validity of methyl mercury hair analysis: mercury monitoring in human scalp/nude mouse modelJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2008Grazyna Zareba Abstract Objective. The grafting of human scalp hair was used as a new application of this method to explore methyl mercury incorporation into human hair and to validate this model for mercury monitoring in hair. Methods. Human scalp grafts were transplanted to athymic BALB/c nude mice. The animals were exposed to methyl mercury either as a single dose i.p. or continuously for 4 months, using ALZET osmotic pumps. The mercury concentration in hair was determined using x-ray fluorescence (XRF) spectrometry by segmental (2 mm) analysis of a single strand, and tissue concentrations were measured by cold vapor atomic absorption analysis. Results. Human scalp hair grown in nude mice showed long-term persistence of human features including the expression of histocompatibility antigens (KAB 3, W 6/32, SF 1-1.1.1) and normal hair morphometry. The disposition of methyl mercury in nude mice followed a one-compartment model with a whole body elimination half-life of 6.7 days (elimination constant, k = 0.1/day). Autoradiographic studies revealed that methyl mercury was rapidly incorporated into areas of the hair follicle undergoing active keratinization. Methyl mercury concentrations in human hair transplanted onto nude mice were two orders of magnitude higher than in blood and attained a mean hair: blood ratio of 217 : 1, similar to ratios reported only in human studies. Conclusions. This study demonstrated that human hair grown on nude mice can record the level of exposure to methyl mercury and can serve as a valuable research tool to study mercury incorporation into human hair. Copyright © 2007 John Wiley & Sons, Ltd. [source] Application of tandem mass spectrometry combined with gas chromatography and headspace solid-phase dynamic extraction for the determination of drugs of abuse in hair samplesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 5 2003Dirk W. Lachenmeier A new method combination, headspace solid-phase dynamic extraction coupled with gas chromatography/tandem mass spectrometry (HS-SPDE/GC/MS/MS), is introduced to determine drugs of abuse in hair samples. This highly automated procedure utilizes SPDE for pre-concentration and on-coating derivatization as well as GC and triple quadrupole MS/MS for selective and sensitive detection. All these steps, apart from washing and cutting of the hair samples, are performed without manual intervention on a robot-like autosampler. SPDE is a solventless extraction technique related to solid-phase microextraction (SPME). The analytes are absorbed from the sample headspace directly into a hollow needle with an internal coating of polydimethylsiloxane by repeated aspirate/dispense cycles. The HS-SPDE/GC/MS/MS procedure was applied to the analysis of methadone, the trimethylsilyl derivatives of cannabinoids and the trifluoroacetyl derivatives of amphetamines and designer drugs. The method was shown to be sensitive with detection limits between 6 and 52 pg/mg hair matrix and precision between 0.4 and 7.8% by the use of an internal standard technique. Linearity was obtained from 0.1,20,ng/mg with coefficients of correlation between 0.995 and 0.999. Compared with conventional methods of hair analysis, HS-SPDE/GC/MS/MS is easier to use, substantially faster, with the degree of sensitivity and reproducibility demanded in clinical and forensic toxicology. The main advantage of the SPDE technique in relation to SPME is the robustness of the capillary. Copyright © 2003 John Wiley & Sons, Ltd. [source] Hair Analysis Versus Conventional Methods of Drug Testing in Substance Abusers Seeking Organ TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010D. L. Haller As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt. [source] Postnatal methadone withdrawal syndrome: hair analysis for detecting chronic exposureACTA PAEDIATRICA, Issue 2 2010Esther Papaseit No abstract is available for this article. [source] | |||||||||||||