Bioconversion of polyphenols and organic acids by gut microbiota of predigested Hibiscus sabdariffa L. calyces and Agave (A. tequilana Weber) fructans assessed in a dynamic in vitro model (TIM-2) of the human colon.

The present work aimed at understanding gut microbiota bioconversion of phenolic compounds (PC) and organic acids in predigested Hibiscus sabdariffa (Hb) calyces and the mixture of Hb and Agave (Agave tequilana Weber) fructans (AF). With this purpose, dried Hb and Hb/AF were predigested with enzymatic treatment, and then fermented in a dynamic in vitro model of the human colon (TIM-2). After HPLC-ESI-QToF-MS analysis of samples taken at 0, 24, 48 and 72 h of fermentation, it was observed that hydroxycinnamic acids, flavanols, flavonols, and anthocyanins were mainly transformed into derivatives of hydroxyphenylpropionic, hydroxyphenylacetic and hydroxybenzoic acids. Moreover, organic acids, such as hydroxycitric and hibiscus acids, were formed along with unidentified lactones and reduced compounds. Interestingly, no differences were observed between microbial-derived metabolites formed after the fermentation of Hb and Hb/AF. In conclusion, colonic fermentation of polyphenol-rich Hb yields a wide range of microbial phenolic metabolites with potential effects on health.

[Social cognition in Parkinson's disease dementia and behavioral variant of frontotemporal dementia]. / Cognicion social en demencia asociada a la enfermedad de Parkinson y en demencia frontotemporal variante conductual.

AIM: To study the presence of alterations in social cognition in Parkinson's disease dementia (PDD) and behavioral variant frontotemporal dementia (bvFTD), to compare the levels of involvement, and to analyze their relevance as a tool to distinguish between both demential profile. SUBJECTS AND METHODS: For this purpose, 34 patients diagnosed with PDD, 21 men and 13 women, with an average age of 70 years and 8 years of education, and 26 patients diagnosed with bvFTD, 9 men and 17 women, with an average age of 68 years and 6 years of education, were assessed. The control group consisted of 30 healthy subjects, with a mean of 66 years of age and 8 of schooling. Reading the Mind in the Eyes was use as an emotional Theory of Mind (ToM) test; First-Order False Belief as a cognitive ToM test; Faux Pas as mixed test, considering their emotional (FPec) and cognitive (FPcc) components; and Iowa Gambling Task for social decision-making. RESULTS: Both groups of patients showed alterations in all tests compared to the control group. A significant difference between PDD and bvFTD was also observed for Reading the Mind in the Eyes test, Faux Pas total score, FPec and FPcc, with lower means and medians for PDD patients on all scores except for FPcc. CONCLUSIONS: This findings suggests that emotional ToM would be most affected PDD patients, while the use of cognitive ToM and social decision-making tests would be restrain tools to differentiate between a type of dementia or another.

TITLE: Cognicion social en demencia asociada a la enfermedad de Parkinson y en demencia frontotemporal variante conductual.Objetivo. Estudiar la presencia de alteraciones en la cognicion social en la demencia asociada a enfermedad de Parkinson (DEP) y en la demencia frontotemporal variante conductual (DFTvc), comparar los niveles de afectacion y analizar su relevancia como herramienta para distinguir entre ambos perfiles demenciales. Sujetos y metodos. Para ello se evaluaron 34 pacientes con diagnostico de DEP, 21 hombres y 13 mujeres, con una media de 70 anos de edad y ocho de escolaridad; y 26 pacientes con diagnostico de DFTvc, nueve hombres y 17 mujeres, con una media de 68 anos de edad y seis de escolaridad. El grupo control quedo conformado por 30 sujetos sanos, con una media de 66 anos de edad y 8 de escolaridad. Se administro lectura de la mente en los ojos como test de teoria de la mente (TdM) emocional, falsa creencia de primer orden como test de TdM cognitiva, faux pas como prueba mixta, considerando sus componentes emocional (FPce) y cognitivo (FPcc), y Iowa Gambling Task para la toma de decisiones sociales. Resultados. Ambos grupos de pacientes mostraron alteraciones en todos los tests en relacion con el grupo control. Se observo, ademas, una diferencia significativa entre los pacientes con DEP y los pacientes con DFTvc para la lectura de la mente en los ojos, el FPce y el FPcc, a favor de los pacientes con DFTvc. Conclusiones. Estos hallazgos sugieren que la TdM emocional estaria mas afectada en la DEP, lo que limitaria el empleo de test de TdM cognitiva y toma de decisiones sociales como herramientas que permitan diferenciar entre un tipo de demencia u otra.

Cognición social en demencia asociada a la enfermedad de Parkinson y en demencia frontotemporal variante conductual / Social cognition in Parkinson’s disease dementia and behavioral variant of frontotemporal dementia

Objetivo. Estudiar la presencia de alteraciones en la cognición social en la demencia asociada a enfermedad de Parkinson (DEP) y en la demencia frontotemporal variante conductual (DFTvc), comparar los niveles de afectación y analizar su relevancia como herramienta para distinguir entre ambos perfiles demenciales. Sujetos y métodos. Para ello se evaluaron 34 pacientes con diagnóstico de DEP, 21 hombres y 13 mujeres, con una media de 70 años de edad y ocho de escolaridad; y 26 pacientes con diagnóstico de DFTvc, nueve hombres y 17 mujeres, con una media de 68 años de edad y seis de escolaridad. El grupo control quedó conformado por 30 sujetos sanos, con una media de 66 años de edad y 8 de escolaridad. Se administró lectura de la mente en los ojos como test de teoría de la mente (TdM) emocional, falsa creencia de primer orden como test de TdM cognitiva, faux pas como prueba mixta, considerando sus componentes emocional (FPce) y cognitivo (FPcc), y Iowa Gambling Task para la toma de decisiones sociales. Resultados. Ambos grupos de pacientes mostraron alteraciones en todos los tests en relación con el grupo control. Se observó, además, una diferencia significativa entre los pacientes con DEP y los pacientes con DFTvc para la lectura de la mente en los ojos, el FPce y el FPcc, a favor de los pacientes con DFTvc. Conclusiones. Estos hallazgos sugieren que la TdM emocional estaría más afectada en la DEP, lo que limitaría el empleo de test de TdM cognitiva y toma de decisiones sociales como herramientas que permitan diferenciar entre un tipo de demencia u otra (AU)

Aim. To study the presence of alterations in social cognition in Parkinson’s disease dementia (PDD) and behavioral variant frontotemporal dementia (bvFTD), to compare the levels of involvement, and to analyze their relevance as a tool to distinguish between both demential profile. Subjects and methods. For this purpose, 34 patients diagnosed with PDD, 21 men and 13 women, with an average age of 70 years and 8 years of education, and 26 patients diagnosed with bvFTD, 9 men and 17 women, with an average age of 68 years and 6 years of education, were assessed. The control group consisted of 30 healthy subjects, with a mean of 66 years of age and 8 of schooling. Reading the Mind in the Eyes was use as an emotional Theory of Mind (ToM) test; First-Order False Belief as a cognitive ToM test; Faux Pas as mixed test, considering their emotional (FPec) and cognitive (FPcc) components; and Iowa Gambling Task for social decision-making. Results. Both groups of patients showed alterations in all tests compared to the control group. A significant difference between PDD and bvFTD was also observed for Reading the Mind in the Eyes test, Faux Pas total score, FPec and FPcc, with lower means and medians for PDD patients on all scores except for FPcc. Conclusions. This findings suggests that emotional ToM would be most affected PDD patients, while the use of cognitive ToM and social decision-making tests would be restrain tools to differentiate between a type of dementia or another (AU)

Disociaciones en teoría de la mente en la variante conductual de la demencia frontotemporal / Dissociations in theory of mind in the behavioral variant of frontotemporal dementia

Corroborar la presencia de disociaciones entre Teoría de la Mente (TdM) cognitiva y emocional en la variante conductual de la Demencia Frontotemporal (DFTvc). Muestra: 20 pacientes, media de edad 67 años, y 6 de escolaridad. Para diagnóstico de DFTvc se administró: Lectura de la Mente en los Ojos (LMO) como prueba de TdM emocional, Falsa creencia de primer orden (FC1O) como prueba de TdM cognitiva, y Faux Pas como prueba mixta. Resultados: El 80% de los pacientes mostró alteraciones en LMO y el 45% en FC1O. Se encontraron diferencias significativas entre LMO y FC1O, y entre Faux Pas y FC1O, y dobles disociaciones. Conclusión: La TdM emocional sería la más afectada en DFTvc. El hallazgo de disociaciones entre tareas podría deberse a que la TdM afectiva es procesada a través de la “teoría de la simulación”, mientras que la TdM cognitiva lo es a través de la “teoría teoría”...

Prenatal alcohol exposure and its repercussion on newborns.

BACKGROUND: Alcohol consumption during pregnancy, even when moderate, implies a risk of impaired neurodevelopment, physical impairments and malformations. Its early identification is essential for establishing preventive measures to diminish disabilities among newborns. METHODS: To determine the frequency of consumption of substance use in pregnant women, we have used the techniques of gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry to detect drugs and markers of chronic consumption of alcohol in meconium. We performed a prospective study during a period of 10 months among 110 infants in our hospital, assessing anthropometry, neuromuscular development and determination of toxic substances in urine and meconium. Furthermore, meconium analysis identified fatty acid ethyl esters (FAEEs) and ethyl glucuronide (Etg). We also conducted a survey regarding the obstetric history, toxic habits, and employment status of the mothers. RESULTS: According to early detection markers analyzed in meconium (FAEE >1000 ng/g and/or Etg >50 ng/g meconium), 34.65% of pregnant women consumed alcohol during pregnancy, and 17% were positive for both markers. Within the positive cases, 50% of those exceeding a FAEE's value of 5000 ng/g in meconium had low birth-weight children. Only 5/110 mothers (4.5%) admitted to occasional alcohol consumption during pregnancy. Nobody admitted to frequent intake. The cocaine test was positive in three cases; two of them were positive for alcohol as well. CONCLUSION: As expected, many screening devices do not accurately capture use during pregnancy and supplemental methods such as meconium analysis of biomarkers of chronic alcohol consumption may be warranted.

Application of hygrine and cuscohygrine as possible markers to distinguish coca chewing from cocaine abuse on WDT and forensic cases.

The objectives of present work are twofold. First, we want to verify that hygrine and cuscohygrine are good markers to distinguish between chewing coca leaves and cocaine abuse. Secondly, we try to develop a quick and easy qualitative method to determine the two mentioned markers. We analyzed two kinds of urine samples: the first group consisted of twenty-four (24) subjects: urine samples were obtained from various types of workers (e.g. doctors, chemists, nurses, technicians, painters, contractors, employees and some retired persons) who admitted chewing coca leaves. Frequency of the habit of chewing coca leaves was variable. They practiced "coqueo" between two (2) and forty-four (44) years. Sixteen (16) of them used alkaline substances to enhance the extraction of cocaine from the leaves The second group of urine samples consisted on thirty-eight (38) cocaine abusers, from forensic cases from Spain and Argentina. A GC/MS qualitative method, performed after liquid-liquid extraction, was developed and validated (the parameters studied were selectivity/specificity, LOD and stability), and then applied to the urine samples. Hygrine and cuscohygrine are good markers to distinguish between chewing coca leaves and cocaine abuse, and the qualitative method presented can be used successfully in workplace drug testing and forensic cases.

Lumbociática como forma de presentación de una malformación vascular: síndrome de Foix-Alajouanine / Sciatica as a presentation form of a vascular malformation: Foix-Alajouanine syndrome

La lumbociática y la lumbalgia son el motivo más frecuente de consulta de origen musculoesquelético en atención primaria y especializada. Las malformaciones vasculares medulares y entre ellas las fístulas arteriovenosas son una rara entidad, pero una causa tratable de tetraplejía progresiva. Los síntomas de aparición pueden ser dolor radicular y lumbar, debilidad y alteración de esfínteres entre otros. La fisiopatología de estas malformaciones explica mediante las variaciones de presión venosa la forma de aparición relacionada con los esfuerzos y la clínica tan variable. Es imprescindible un diagnóstico diferencial con otras afecciones con sintomatología neurológica. El diagnóstico y tratamiento precoz puede evitar la progresión. Presentamos el caso de un varón de 40 años diagnosticado inicialmente de lumbociática, que evolucionó de manera aguda a una paraparesia y cuyo diagnóstico resultó ser una fístula arteriovenosa medular. Describimos los tipos de malformaciones arteriovenosas y su fisiopatología (AU)

Sciatica and low back pain are the most frequent reasons for skeletal muscle consultation in primary and specialized care. Spinal cord vascular malformations, among them arteriovenous fistulae, are a rare but a treatable condition of progressive paraplegia and tetraplegia. The initial symptoms may be radicular and lumbar pain, weakness and sphincters disorders, among others. The pathophysiology of these malformations explains the presentation form related to efforts and such variable clinical symptoms according to the variation of venous pressure. A differential diagnosis must be made in regards to other diseases that have neurological symptoms. Early diagnosis and treatment can prevent the disease-progression. We report the case of a 40-year old man initially diagnosed of sciatica that evolved to acute paraparesia. Finally, he was diagnosed of spinal arteriovenous fistula. We describe the different types of arteriovenous malformations and their pathophysiology (AU)

Hygrine and cuscohygrine as possible markers to distinguish coca chewing from cocaine abuse in workplace drug testing.

Cocaine abuse is widespread all over the world, and is performed generally by sniffing, injecting or smoking cocaine or crack. The distinction between the recreational use of cocaine from the practice of the so called "coqueo" is still an issue in those countries where this habit is diffused and where it is not considered an addiction, by this reason is necessary to develop a method for to distinguish the coca chewers and cocaine abusers. The use of an unique marker to distinguish between cocaine abuse and chewing of coca leaves is of fundamental importance in those countries where this habit is diffused. Certain alkaloids of the leaves of Erythroxylum coca are lost during the process of extraction/purification of cocaine and it is not possible to find them neither in seizures of chlorhidrate of cocaine nor urine samples of cocaine abusers. These markers are the hygrine and cuscohygrine that are present in the leaves of E. coca. A fast GC/MS method involving a liquid:liquid extraction procedure with tertbutylmethylether (TBME) is proposed for the determination of some alkaloids in cocaine leaves, cocaine seizures and biological samples. All specimens were alkalinized to pH 9 with a carbonate/bicarbonate buffer and then extracted with TBME. The analysis was carry out by GC/MS with electron impact at 70 eV and in full scan mode. The results demonstrate that hygrine and cuscohygrine are not found neither in the urine of cocaine abusers nor in cocaine seizures. For this reason this compounds could be considered as markers of coca chewing. This developed method permits to distinguish coca chewing from cocaine abuse in workplace drug testing through the analysis of urine samples.

Hair testing for cocaine and metabolites by GC/MS: criteria to quantitatively assess cocaine use.

A simple, rapid and sensitive method has been developed and validated for the determination of cocaine and its main metabolites (benzoylecgonine and cocaethylene) in human hair. The method involved solid-phase extraction with an Oasis HLB extraction cartridge and subsequent analysis by GC/MS. The limit of detection was 0.01 ng mg(-1) for cocaine, 0.04 for benzoylecgonine and 0.03 for cocaethylene. The method validation included linearity (with a correlation coefficient >0.99 over the range 0.2-50 ng mg(-1) ), intra- and inter-day precision (always lower than 12%) and accuracy (mean relative error always below 17%) to meet the bioanalytical acceptance criteria. The procedure was further applied to 40 hair samples from self-reported cocaine users arrested by the police who provided a positive urine-analysis for cocaine, and was demonstrated to be suitable for its application in forensic toxicology. New approaches were raised to detect false-negative results that allow a better interpretation of hair testing results.

Analysis of six benzodiazepines in vitreous humor by high-performance liquid chromatography-photodiode-array detection.

The purpose of this study was to validate a high-performance liquid chromatography-photodiode-array detetion method for the determination of six benzodiazepines in vitreous humor. The sample preparation was carried out using solid-phase extraction with Oasis HLB cartridges and 10% acetic acid/MeOH as elution solvent. The vitreous humor is less affected by postmortem changes and is a very useful sample when blood or urine specimens are not available. Linear curves for bromazepam, alprazolam, lorazepam, lormetazepam, diazepam, and tetrazepam were obtained within the range 0.03-3 µg/mL, with coefficients of correlation lower than 0.999. The limit of detection was 3 ng/mL, and the lower limit of quantification was 30 ng/mL for each benzodiazepine. Intra- and interassay for precision and accuracy provided results less than 16.81% and 16.78%, respectively. Recoveries were higher than 68.51% in all cases. Finally, the method was applied to determine benzodiazepines in vitreous humor from intoxicated patients.

Positive response to imatinib mesylate therapy for childhood chronic myeloid leukemia

Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3 percent of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

Positive response to imatinib mesylate therapy for childhood chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3% of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

Validation of ELISA screening and LC-MS/MS confirmation methods for cocaine in hair after simple extraction.

This article describes an easy and innovative extraction procedure for cocaine and its primary metabolite, benzoylecgonine (BE), from hair consisting of sonication with H(2)O/0.1% formic acid for 4 h. The same extract was used for screening with an enzyme-linked immunoassay (ELISA) and confirmation by liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the ELISA screening test a cutoff of 0.5 ng/mg was used according to the Society of Hair Testing recommendations. LC-MS/MS limits of detection (LODs) were established to be 10 pg/mg and 1 pg/mg for cocaine and BE, respectively. Linearity was obtained over a range of 0.2-5 ng/mg for BE (target analyte) in the ELISA screening test, while in the LC-MS/MS method the range was 0.10-10 ng/mg for cocaine and 0.01-10 ng/mg for BE. Intra- and interbatch coefficients of variation and mean relative errors were less than 20% for all analytes and concentrations studied. The validated ELISA and LC-MS/MS methods were applied to 48 hair samples and the results of both methods were compared; ELISA demonstrated a sensitivity and specificity of 89.2% and 10.8%.

Cocaine and opiates use in pregnancy: detection of drugs in neonatal meconium and urine.

In this study, the case of a newborn with symptoms of hyperexcitability was analyzed. After it was confirmed in the hospital that the mother had consumed drugs during pregnancy using an enzyme multiplied immunoassay technique, samples of the newborn's urine and meconium were sent to our laboratory to observe the evolution in the distribution of cocaine and opiates during the days following birth. For urine analysis, screening was done with an immunoassay technique, and the confirmation was done by gas chromatography-mass spectrometry (GC-MS) according to a published method. A GC-MS method for simultaneous analysis of cocaine, benzoylecgonine, codeine, morphine, and 6-acetylmorphine in meconium is described. GC-MS confirmation of urine and meconium results showed consumption of cocaine and codeine during pregnancy and also showed the levels of drugs gradually declined, totally disappearing by the third day.

Optimization of a rapid microwave-assisted extraction method for the simultaneous determination of opiates, cocaine and their metabolites in human hair.

A rapid and cleanup-free microwave-assisted extraction (MAE) method is proposed for the simultaneous extraction of six illegal drugs of abuse - cocaine, benzoylecgonine (BZE), cocaethylene (CCE), morphine, 6-monoacethylmorphine (6AM) and codeine - from human hair samples. The analytes were determined using high performance liquid chromatography (HPLC) with photodiode array UV detection. The influence of several variables on the efficiency of the MAE procedure was investigated in detail by a multi-objective optimization approach based on a hybrid experimental design (17 experiments) and desirability functions. Six drugs were successfully extracted from human hair with recoveries close to 100% and good reproducibility (<3.6% RSD) under the optimal MAE conditions: 11 mL dichloromethane (DCM) extraction solvent, 60 degrees C extraction temperature, 9 min extraction time and 0.5 mL of methanol (MeOH) added to 50mg of the hair sample in the extraction vessels. Limits of quantification of 0.2 ng mg(-1) were found for the studied compounds. A comparison of sample preparation procedures, including MAE, enzymatic digestion and digestion by aqueous acids, was also conducted. The results indicated that the global behaviour of sample procedures provided similar satisfactory recoveries ranging from 86 to 100%. Indeed, the MAE procedure resulted in a reduction of extraction time by 100-fold and the elimination of cleanup steps. Slightly higher recoveries of morphine, 6AM, BZE and CCE, at 1 ng mg(-1) concentration level and cocaine at 40 ng mg(-1) concentration level, were achieved using MAE. Lastly, the proposed MAE method was applied to several human hair samples from multidrug abusers.

Determination of cocaine and heroin with their respective metabolites in meconium by gas chromatography-mass spectrometry.

The analysis of meconium specimens is a relatively accurate method for the detection of fetal exposure to drugs. The purpose of this study was to develop and validate a method for meconium sample preparation for a gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cocaine, benzoylecgonine, codeine, morphine and 6-monoacetylmorphine. The analytes were initially extracted from the matrix by methanol. Subsequently a solid-phase extraction with Waters Oasis HLB cartridges was applied. Analytes were determined in GC-MS single monitoring mode. The method was validated in the range 40-2000 ng g(-1) using 0.5 g of meconium per assay. The detector response was linear over the studied range, and limits of quantitation and detection were found to be acceptable. Intra- and inter-batch coefficients of variation oscillated between 2.54% and 20.5%, and mean relative errors were in the range 0.79%-19.9%. The recoveries were higher than 42.1% in all cases. Finally the method was applied to analysis of meconium in newborns to assess fetal exposure to cocaine and opiates.

A new automated flow cytometry data analysis approach for the diagnostic screening of neoplastic B-cell disorders in peripheral blood samples with absolute lymphocytosis.

Currently, multiparameter flow cytometry immunophenotyping is the selected method for the differential diagnostic screening between reactive lymphocytosis and neoplastic B-cell chronic lymphoproliferative disorders (B-CLPD). Despite this, current multiparameter flow cytometry data analysis approaches still remain subjective due to the need of experienced personnel for both data analysis and interpretation of the results. In this study, we describe and validate a new automated method based on vector quantization algorithms to analyze multiparameter flow cytometry immunophenotyping data in a series of 307 peripheral blood (PB) samples. Our results show that the automated method of analysis proposed compares well with currently used manual approach and significantly improves semiautomated approaches and, that by using it, a highly efficient discrimination with 100% specificity and 100% sensitivity can be made between normal/reactive PB samples and cases with B-CLPD based on the total B-cell number and/or the sIgkappa+/sIglambda+ B-cell ratio. In addition, the method proved to be able to detect the presence of pathologic neoplastic B-cells even when these are present at low frequencies (<5% of all lymphocytes in the sample) and in poor-quality samples enriched in 'noise' events.

GC-FID determination of cocaine and its metabolites in human bile and vitreous humor.

Gas chromatography was used in combination with flame ionization detection (GC-FID) to develop a method for determining cocaine and its two metabolites, benzoylecgonine (BEG) and ecgonine methyl ester (EME), in bile and vitreous humor. The method used a 12 m x 0.2 mm i.d. column of 0.33 microm film thickness packed with 5% phenylmethylsiloxane, and proadifen as a reference compound. Drug-free bile and vitreous humor samples were used to prepare solutions of the target compounds at concentrations over the range 0.1-4 microg ml(-1) that were subjected to solid-phase extraction through Bond Elut Certify columns and derivatized with 99:1 (v/v) N,O-bis-trimethylsilyltrifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS). Calibration graphs were highly linear, with correlation coefficients above 0.99 in all instances. Also, the precision of the method was found to be quite acceptable, with coefficients of variation less than 5% for bile and less than 7% for vitreous humor. The average extraction yields ranged from 73.6% to 91.2% for bile and from 71.5% to 92.2% for vitreous humor. The proposed method was used to analyse 26 samples of bile and as many of vitreous humor from individuals fatally poisoned by cocaine, whether alone or in combination with other drugs. The mean drug levels found were 0.75 and 1.54 microg ml(-1) for cocaine in bile and vitreous humor, respectively, 6.35 and 0.94 microg ml(-1) for BEG, and 2.18 and 0.61 microg ml(-1) for EME.

HPLC-DAD determination of opioids, cocaine and their metabolites in plasma.

High performance liquid chromatography with diode array detection (HPLC-DAD) was used to develop a method for the simultaneous determination of morphine, codeine, 6-acetylmorphine (6AM), cocaine, benzoylecgonine (BEG), cocaethylene, methadone and its metabolite, 2-ethylidene-1,5-dimethyldiphenylpyrrolidine (EDDP), in plasma. Following solid-phase extraction with Bond Elut Certify cartridges, chromatography was performed on an X-Terra RP8 column (250 mm x 4.6 mm i.d., 5 microm particle size), using acetonitrile-phosphate buffer pH 6.53 as mobile phase and elution in the gradient mode. The detector response was linear at concentrations over the range 0.1-10 microg/mL in plasma, and the correlation coefficients for the eight drugs studied were all higher than 0.99. The average extraction recoveries from plasma ranged from 60% for BEG to 95% for methadone. The precision was acceptable, with coefficients of variation oscillating between 2.55% and 6.45%. The accuracy was found to be within satisfactory limits (+/- 8.1%). Finally, the method was applied to 21 plasma samples from fatal overdoses, obtaining positive results for two or more drugs.

A new GC-MS method for the determination of five amphetamines in human hair.

A new gas chromatography-mass spectrometry method for the simultaneous identification and quantitation of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethamphetamine (MDEA) in hair is proposed. Hair was hydrolyzed in 1 M NaOH at 40 degrees C, subjected to extraction with 4:1 (v/v) methylene chloride/isopropanol, and derivatized with pentafluoropropionic anhydride (PFPA) and ethyl acetate. Calibration curves for the five analytes were constructed over the concentration range 0.5-25.0 ng/mg, using their pentadeuterated analogues as internal standards. The limits of detection and quantitation obtained were 0.045 and 0.151 ng/mg for AP; 0.014 and 0.048 ng/mg for MA; 0.013 and 0.043 ng/mg for MDA; 0.017 and 0.057 ng/mg for MDMA; and 0.007 and 0.023 ng/mg for MDEA. The accuracy of the method was found to be in the range +/- 9%, and the coefficients of variation were less than 8%. Overall, 24 hair specimens tested positive for one or more amphetamines, with average concentrations of 0.88 ng/mg for AP, 10.14 ng/mg for MA, 1.30 ng/mg for MDA, and 8.87 ng/mg for MDMA. Only one specimen tested positive for MDEA with a concentration of 0.84 ng/mg.