Microextraction by Packed Sorbent as a Clean-up Approach for the Determination of Ketamine and Norketamine in Hair by Gas Chromatography--Tandem Mass Spectrometry.

The use of new psychoactive substances has been increasing and constitutes a social and public health problem, and hence, toxicological analysis has become of utmost importance for the detection of such substances. In this article, we present the development and full validation of a simple, user and environmentally friendly, cheap and suitable method for the determination of ketamine and its main metabolite norketamine in hair samples. The procedure included using a miniaturized procedure-microextraction by packed sorbent with mixed-mode sorbent-for sample clean-up. Organic solvents use was minimal, and it was possible to obtain a linear method (0.05-10 ng/mg for both analytes). The extraction efficiency ranged from 32 to 61%, which did not impair sensitivity. The method proved to be selective, precise, accurate and suitable for routine analysis for the determination of said compounds in 50-mg hair samples.

Eustigmatophyte strains with potential interest in cancer prevention and treatment: partial chemical characterization and evaluation of cytotoxic and antioxidant activity.

The interest in bioactive compounds from microalgae is increasing since they have medicinal and nutritional areas. The present work aims to evaluate the potential pharmaceutical interest of extracts from three eustigmatophyte strains from the Coimbra Collection of Algae (ACOI): Chlorobotrys gloeothece, Chlorobotrys regularis and Characiopsis aquilonaris. Antioxidant and antiproliferative activities were determined as well as chlorophyll a, carotenoid and phenolic total contents. In addition, major pigments and sterols were identified and quantified. The three strains were grown until the stationary phase and then the biomass was extracted. Antioxidant activity was measured by TEAC, DPPH and FRAP assays and antiproliferative effect was assessed by the MTT method on MCF-7, PC-3 and NHDF cells. The pigment and phenolic total contents were determined by spectrophotometry. Of these strains, C. aquilonaris showed the highest antioxidant activity measured by TEAC and FRAP assays (23.98 ± 0.01 µmol TE eq g-1 DW and 42.57 ± 0.04 µmol TE eq g-1 DW, respectively), a selective effect in reduting MCF-7 cells proliferation and a larger amount of chlorophyll a, carotenoids and phenolic content (18.40 ± 0.00 µg chlorophyll a mg-1 DW, 2.27 ± 0.00 mg carotenoids g-1 DW and 6.23 ± 0.01 mg GAE g-1 DW, respectively). A positive correlation between chlorophyll a and TEAC assay was observed, as well as between carotenoids and TEAC and FRAP assays, suggesting these compounds as important contributors to significant antioxidant activity. Violaxanthin, cholesterol and stigmasterol were present in larger amount in C. aquilonaris while C. regularis showed a higher amount of ß-carotene. These results suggest that these three ACOI eustigmatophytes are promising for applications in the improvement of human health, particularly in cancer prevention and treatment.

Microextraction by Packed Sorbent as a Novel Strategy for Sample Clean-Up in the Determination of Methadone and EDDP in Hair.

A microextraction by packed sorbent (MEPS) procedure for rapid concentration of methadone and its primary metabolite (EDDP) in hair samples was developed. The miniaturized approach coupled to gas chromatography with tandem mass spectrometry (GC-MS-MS) was successfully validated. Hair samples (50 mg) were incubated with 1 mL of 1 M sodium hydroxide for 45 min at 50°C, time after which the extract was neutralized by adding 100 µL of 20% formic acid. Subsequently, MEPS was applied using a M1 sorbent (4 mg; 80% C8 and 20% strong cation-exchange (SCX)), first conditioned with three 250-µL cycles of methanol and three 250-µL cycles of 2% formic acid. The extract load occurred with nine 150-µL cycles followed by a washing step involving three 50-µL cycles with 3.36% formic acid. For the elution of the analytes, six 100-µL cycles of 2.36% ammonium hydroxide in methanol were applied. The method was linear from 0.01 to 5 ng/mg, for both compounds, presenting determination coefficients greater than 0.99. Precision and accuracy were in accordance with the statements of international guidelines for method validation. This new miniaturized approach allowed obtaining recoveries ranging from 73 to 109% for methadone and 84 to 110% for EDDP, proving to be an excellent alternative to classic approaches, as well as other miniaturized procedures.

Sensitive determination of THC and main metabolites in human plasma by means of microextraction in packed sorbent and gas chromatography-tandem mass spectrometry.

Cannabis is one of the most available and consumed illicit drug in the world and its identification and quantification in biological specimens can be a challenge given its low concentrations in body fluids. The present work describes a fast and fully validated procedure for the simultaneous detection and quantification of ▵9-tetrahydrocannabinol (▵9_THC) and its two main metabolites 11-hydroxy ▵9_tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-▵9- tetrahydrocannbinol (THC-COOH) in plasma samples using microextraction by packed sorbent (MEPS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). A small plasma volume (0.25mL) pre-diluted (1:20), was extracted with MEPS M1 sorbent as follows: conditioning (4 cycles of 250µL methanol and 4 cycles of 250µL 0.1% formic acid in water); sample load (26 cycles of 250µL); wash (100µL of 3% acetic acid in water followed by 100µL 5% methanol in water); and elution (6 cycles of 100µL of 10% ammonium hydroxide in methanol). The procedure allowed the quantification of all analytes in the range of 0.1-30ng/mL. Recoveries ranged from 53 to 78% (THC), 57 to 66% (11-OH-THC) and 62 to 65% (THC-COOH), allowing the limits of detection and quantification to be set at 0.1ng/mL for all compounds. Intra-day precision and accuracy revealed coefficients of variation (CVs) lower than 10% at the studied concentrations, with a mean relative error within±9%, while inter-day precision and accuracy showed CVs lower than 15% for all analytes at the tested concentrations, with an inaccuracy within±8%.

Determination of antipsychotic drugs in hospital and wastewater treatment plant samples by gas chromatography/tandem mass spectrometry.

The development and performance evaluation of a method for the simultaneous determination of six antipsychotic drugs in hospital effluents and wastewater treatment plants (WWTP) samples are herein presented. The method involves an off-line mixed mode (reversed-phase and strong cation exchange) solid phase extraction (SPE) with gas chromatography (GC) coupled to tandem mass spectrometry (MS/MS). The present methodology was validated following internationally accepted criteria, and the studied parameters included selectivity, linearity, limits of detection (LOD) and quantitation (LLOQ), instrumental limits, precision and accuracy, stability and recovery. The procedure was linear for concentrations ranging from 0.1 to 10µg/L (0.02 to 2µg/L for haloperidol), with determination coefficients higher than 0.99 for all analytes. Intra- and inter-day precision was lower than 15% for all analytes at the studied concentrations, while accuracy remained between a ±15% interval. Recoveries ranged from 31% to 83%. Low LODs were achieved, between 2 and 10ng/L, allowing a reliable identification of all analytes at trace levels, using only 50mL as sample volume. All studied parameters complied with the defined criteria and the method was successfully applied to gather preliminary results of the determination of antipsychotics on hospital effluents and on influent and effluent of WWTPs, opening perspectives for the study of their fate in the aquatic environment.

Synthesis of oxocarbon-encapsulated gold nanoparticles with blue-shifted localized surface plasmon resonance by pulsed laser ablation in water with CO2 absorbers.

Colloidal suspensions of oxocarbon-encapsulated gold nanoparticles have been synthesized in a one-step procedure by pulsed-laser ablation (PLA) at 532 nm of a solid gold target placed in aqueous solution containing CO2 absorbers, but without any stabilizing agent. Multi-wavelength surface enhanced Raman spectroscopy allows the identification of adsorbed amorphous carbon and graphite, Au-carbonyl, Au coordinated CO2-derived bicarbonates/carbonates and hydroxyl groups around the AuNPs core. Scanning electron microscopy, energy dispersive x-ray analysis and high resolution transmission electron microscopy highlight the organic shell structure around the crystalline metal core. The stability of the colloidal solution of nanocomposites (NCs) seems to be driven by solvation forces and is achieved only in neutral or basic pH using monovalent hydroxide counter-ions (NaOH, KOH). The NCs are characterized by a blue shift of the localized surface plasmon resonance (LSPR) band typical of metal-ligand stabilization by terminal π-back bonding, attributed to a core charging effect caused by Au-carbonyls. Total organic carbon measurements detect the final content of organic carbon in the colloidal solution of NCs that is about six times higher than the value of the water solution used to perform PLA. The colloidal dispersions of NCs are stable for months and are applied as analytical probes in amino glycoside antibiotic LSPR based sensing.

Microbial communities analysis assessed by pyrosequencing--a new approach applied to conservation state studies of mural paintings.

The knowledge about the microbial communities present in mural paintings is of utmost importance to develop effective conservation and mitigation strategies. The present paper describes a methodological approach for the detailed characterisation of microorganisms thriving in mural paintings by combining culture-dependent methods that allow the identification of microorganisms capable of growing in the laboratory conditions and to obtain high cell densities for further studies, and culture independent methods, such as denaturing gradient gel electrophoresis (DGGE) and pyrosequencing. The coupled use of culture-dependent methods and DGGE does not give enough information to investigate the diversity and abundance of microorganisms present in wall paintings. Pyrosequencing, a novel molecular technique, used here for the first time in this area of research, allowed the identification of a large number of microorganisms, confirming some already identified by the cultivation-dependent methods such as fungi of the genera Penicillium and Cladosporium, but also providing a great contribution in the identification of several genera and species, not previously identified in these artworks, giving also a detailed overview of contaminants which was not possible with the other approaches. The results obtained on several mural painting samples show a strong relationship between the most deteriorated areas of the paintings and higher microbial contamination.

Estudio piloto prospectivo del deterioro cognitivo en pacientes oncológicos paliativos ambulatorios / Prospective pilot study of cognitive impairment in palliative oncologic outpatiens

Diversos estudios sugieren que los trastornos cognitivos pueden ser frecuentes en pacientes con cáncer avanzado. Su prevalencia es muy variable (8-90%) y son pocos los estudios prospectivos con pacientes paliativos ambulatorios. Objetivo: estudiar la prevalencia del deterioro cognoscitivo en pacientes paliativos oncológicos ambulatorios y precisar la prueba de cribado cognitivo más sensible. Método: Muestra: dieciséis pacientes oncológicos paliativos, 7 hombres y 9mujeres, con una media de edad de 73 años (±12,9) y 3,8 años de escolarización (±3,3). El diagnóstico mayoritario fue de neoplasia digestiva. Durante la valoración cognitiva tres pacientes estaban tratados con mórficos. Material: se administró ambulatoriamente una batería cognitiva que incluía el mini-examen cognitivo de Lobo (MEC), la escala de evaluación cognitiva de Clifton (CAS), la evaluación rápida de funciones cognitivas de Gil (ERFC) y el subtest de claves del WAIS-III. Resultados: se excluyeron cuatro pacientes al presentar, tras evaluación neuropsicológica, un deterioro cognitivo cortical difuso sugestivo de posible demencia degenerativa primaria. De los 12 pacientes restantes evaluados, el CAS y el ERFC objetivaron un deterioro cognitivo leve en 4 y 9 casos respectivamente. Mediante el MEC se detectó un solo caso. Conclusiones: la mayoría de los pacientes oncológicos paliativos tienen un déficit cognoscitivo leve y, posiblemente, específico. El MEC parece tener menor sensibilidad para detectar dicho trastorno, respecto al CASy el ERFC. El enlentecimiento motor y mental parecen ser el deterioro cognoscitivo más característico de dicha población. Finalmente, el déficit cognitivo no parece ser una variable relevante para predecir la esperanza de vida (AU)

Several studies suggest that cognitive impairment can often appear in advanced cancer patients. Its prevalence is very variable (8-90%) and there is very little prospective research with palliative outpatients. Objective: studying the prevalence of the cognitive impairment in palliative oncologic outpatients and specifying the most sensitive cognitive screening test. Method: Subjects: sixteen onchological palliative patients, 7 men and 9 women, with an average age of 73 years old (±12,9) and 3,8 school years (±3,3). The main diagnosis was the digestive neoplasia. During the cognitive examination, three of the patients were being treated with morphic. Material: a battery of cognitive tests was administered in an ambulatory way. This battery included the mini-exam cognitive of Lobo (MEC), the cognitive evaluation scale of Clifton (CAS), the quick assessment of cognitive function of Gil (ERFC) and the subtest of digit symbol from WAIS-III. Results: four patients was excluded, after neuropsychological assessment, because they showed a diffuse cortical cognitive failure, which suggested the possibility of the existence of dementia. CAS and ERFC showed, in the rest of the 12 patients, a light cognitive impairment in 4 and 9 of the subjects, respectively. By the use of MEC, only one case was detected. Conclusion: the majority of the palliative onchological outpatient shave specific light cognitive deterioration. MEC seems to have less perceptibility than CAS and ERFC to detect that impairment. The slowness of mind activity and movements seem to be the most common cognitive failure in this group of outpatients. Finally, cognitive failure is not related to mortality risk (AU))

[Alport-Perkoff's syndrome (two cases report)]. / Síndrome de Alport-Perkoff (a propósito de dos observaciones

Two patients affected with Alport's syndrome belonging respectively to two families with a high incidence of urinary, auditive and ocular symtoms, are described. The most relevant features are commented pointing out that Alport's syndrome could be a structural malformation of the whole or only one part of a type of colagen probably specific of the basal membrane of the glomerulus which could be more easily affected forming toxic metabolites. Finally a reference to the histologic study is made.