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Smoking crack cocaine involves the inhalation of cocaine and its pyrolysis product, anhydroecgonine methyl ester (AEME). There is evidence that cocaine is neurotoxic, but the neurotoxicity of AEME has never been evaluated. AEME seems to have cholinergic agonist properties in the cardiovascular system; however, there are no reports on its effects in the central nervous system. The aim of this study was to investigate the neurotoxicity of AEME and its possible cholinergic effects in rat primary hippocampal cell cultures that were exposed to different concentrations of AEME, cocaine and to a cocaine-AEME combination. We also evaluated the involvement of muscarinic cholinergic receptors in the neuronal death induced by these treatments using concomitant incubation of the cells with atropine. Neuronal injury was assessed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. The results of the viability assays showed that AEME is a neurotoxic agent that has greater neurotoxic potential than cocaine after 24 and 48 hours of exposure. We also showed that incubation for 48 hours with the combination of both compounds in equipotent concentrations had an additive neurotoxic effect. Although both substances decreased cell viability in the MTT assay, only cocaine increased LDH release. Caspase 3 activity was increased after incubation with 1 mM cocaine and after 6 hours of 0.1 and 1 mM AEME exposure. Atropine prevented the AEME-induced neurotoxicity, which suggests that muscarinic cholinergic receptors are involved in AEME's effects. In addition, binding experiments confirmed that AEME has an affinity for muscarinic cholinergic receptors. Nevertheless, atropine was not able to prevent the neurotoxicity produced by cocaine and the cocaine-AEME combination, suggesting that these treatments activated other neuronal death pathways. Our results suggest a higher risk for neurotoxicity after smoking crack cocaine than after cocaine use alone. Language: en

During criminal investigations involving firearms, the detection of gunshot residues (GSRs) is one of the most important evidences. In the present study, a new method to identify trace evidences of GSRs, deposited around the bullet entrance hole, in different types of fabrics used as targets, is described. The experiments were carried out using a 0.38-inch caliber revolver, and 9-mm and 0.40-inch caliber pistols. Testimonies of 2.25 cm(2) of the fabrics were cut around the bullet entrance and digested with 10% nitric acid. Antimony, barium, and lead were analyzed in the remaining solution using a sector field inductively coupled plasma mass spectrometer. The concentrations of the elements were detected at levels up to few microgram per square centimeter. The use of ternary graphics allowed us to identify specific patterns of distribution for blank samples and the clear distinction between the revolver and pistols used. Language: en

This paper describes the development and validation of simple and selective analytical method for determination of 3.4-methylenedioxymethamphetamine (MDMA) in Ecstasy tablets, using high performance liquid chromatography with fluorescence detection. Analysis was performed in a reversed phase column (LiChrospher 100 C18, 150 x 4.6 mm, 5 µm), isocratic elution with phosphate buffer 25 mmol/L pH 3.0 and acetonitrile (95:5, v/v). The method presents adequate linearity, selectivity, precision and accuracy. MDMA concentration in analyzed tablets showed a remarkable variability (from 8.5 to 59.5 mg/tablet) although the tablet weights were uniform, indicating poor manufacturing control thus imposing additional health risks to the users.

A rapid and simple method was optimized for determination of Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabinol (CBN) contents in cannabis products by gas chromatography with flame-ionization detection (GC-FID), using diazepam as internal standard. All parameters of validation of the method such as linearity, intraassay precision, and limits of detection and quantification of the analytes were satisfactory. Using the described method, cannabinoid contents of 55 cannabis product samples seized in Sao Paulo City, Brazil, in 2006 and 2007 were measured. Δ9-THC content in marijuana and hashish samples varied between 0.08% and 5.5%, with an average of 2.5%. The phenotypic ratio showed that the products were able to be designated as “drug type.”

The consumption of synthetic drugs, generally known as designer drugs, has increased drastically in all parts of the world. Typical constituents of designer synthetic drugs are chemical substances derived from amphetamine but significant differences in effects caused and duration may result. In May, 2005, the civil state police of Sao Paulo seized thirty-one gelatinous capsules containing a very small quantity of a white powder inside (approximately 1.5 mg per capsule). This paper describes the analytical assays that were used to identify the seized material. Preliminary assays using colorimetric tests and high performance thin-layer chromatography indicated that the capsules content could be an amphetamine derivative. In the capillary zone electrophoresis assay, it was possible to observe that the analyzed material had basic characteristics. Mass spectrometry analysis revealed that the compound had the same molecular mass as 2,5-dimethoxy-4-bromoamphetamine (DOB) and its identity was confirmed through collision-induced dissociation (CID) experiments. Finally, the comparison of infrared sample spectrum with a spectra library provided further evidence of the DOB presence in the seized material. Although a reference standard material was not available, the information gathered from the different assays allowed the conclusion that the substance was, in fact, DOB, a substance with a powerful hallucinogenic action of proscribed use in the country and which was seized and identified for the first time in Brazil.

The most popular handgun in Brazil is the single round-barrel caliber 0.38 revolver. In recent years, however, owing to the modernization of police arms and their availability on the legal and illicit markets, pistols have become increasingly popular and currently represent about 20% of police seizures. In a previous paper we presented a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediamine-tetraacetic acid (EDTA) solution as a complexing agent on moistened swabs with subsequent detection using sector field-high resolution-inductively coupled plasma-mass spectrometry (SF-HR-ICP-MS). In the present paper, we discuss the capability of this methodology to identify antimony (Sb), barium (Ba) and lead (Pb) on the hands of volunteers after shot tests with 9 mm and 0.40 in. caliber pistols. Two types of munitions were tested: 9 mm Taurus and clean range. The use of a technique with high sensitivity, such as SF-HR-ICP-MS, permits the identification of low concentrations (less than 1 microg/L) of metals in firearm residue and constitutes a powerful tool in forensic science. We also discuss the importance of the sampling procedure, including collection from a different body part than the gun hand of the suspect. Comparison of the analytical data obtained allows clear discrimination between samples from the hands of shooters and non-shooters.

The main task of this work was to verify the existing differences in the elemental composition of samples seized in the main Brazilian regions of marijuana production, previously separated by their carbon and nitrogen stable isotope results, and to use these differences to classify the samples according to their geographical origins. The sector field inductively coupled plasma mass spectrometry technique (HR-ICP-MS) was the analytical technique applied and the data analysis was performed using hierarchical cluster and linear discriminant analysis. Results indicate that samples from different regions present different chemical profiles that appear in accordance to the geological characteristics of each region. The most relevant parameters were carbon and nitrogen stable isotopes, copper, cobalt, barium, lanthanum, zinc, iron, yttrium and manganese. An interesting product of this work was to demonstrate the possibility of using seized samples to create a national databank for monitoring the geographical origin of marijuana consumed in the country. Este trabalho teve como principal objetivo verificar as diferenças existentes na composição elementar de amostras de Cannabis, apreendidas em diferentes regiões produtoras do país, previamente separadas através da análise de isótopos estáveis de carbono e nitrogênio, e utilizar estas diferenças para classificar as amostras de acordo com sua origem geográfica. A técnica analítica empregada foi a de espectrometria de massas de dupla focalização com fonte de plasma acoplado indutivamente (HR-ICP-MS), e a avaliação dos dados foi realizada utilizando-se a análise de agrupamentos (hierarchical cluster analysis) e de discriminantes linear. Os resultados indicam que amostras provenientes de regiões diferentes apresentam perfis químicos diferentes e estes por sua vez parecem estar relacionadas com as características geológicas das regiões consideradas. Os parâmetros mais importantes nesta avaliação foram os isótopos estáveis de carbono e nitrogênio e os níveis de cobre, cobalto, bário, lantânio, zinco, ferro, ítrio e manganês. Este trabalho demonstrou a possibilidade de se utilizar amostras apreendidas nas ruas para a criação de um banco de dados para o monitoramento da maconha consumida no país.

Neste trabalho estudamos uma nova classe de superpotenciais em mecânica quântica supersimétrica, os quais denominamos de modulares, por serem funções do módulo da coordenada x. O superpotencial de partida proposto é da forma x |x|. Esta ideia permite tornar solúvel exatamente, a energia zero, um incontável número de potenciais gerados por estas funções no âmbito da mecânica quântica supersimétrica. Exploramos algumas aplicações para estes superpotenciais, com ênfase para uma representação da molécula de amônia supersimétrica e, em particular, mostramos que um sistema muito estudado na literatura, gerado pelo superpotencial x 1/x, pode ser resolvido mais facilmente recorrendo-se à representação modular. Procuramos estudar as soluções exatas ou aproximadas - do espectro de energias dos Hamiltonianos parceiros supersimétricos utilizando metodologias adequadas ao respectivo caso, incluindo-se o conhecido potencial x4, sendo que o método variacional de coeficientes de funções foi o que melhor se adaptou ao estudo. Este método, pouco utilizado até o momento na literatura, permitiu não apenas resolver com excelente aproximação os primeiros níveis do sistema em estudo, como também comprovou a supersimetria do sistema modular. Mostramos também que em sistemas quânticos supersimétricos, a equação de Schroedinger pode ser colocada na forma da equação de Sturm-Liouville e apresentar soluções de polinômios ortogonais, sendo que a função-peso de tais polinômios é gerada pelo superpotencial. Uma breve abordagem da simetria PT envolvendo diretamente o potencial por nós proposto também foi investigada, e mostramos que o sistema é equivalente a um Hamiltoniano não Hermitiano com potencial V(z) = (z4). In this work we study a new class of superpotentials in supersymmetric quantum mechanics, which we call modular because of their dependence on the modulus of the x coordinate. The starting superpotential is of the form x |x|. This idea helps make exactly solvable, at zero energy, several potentials generated by these functions in the context of supersymmetric quantum mechanics. We explore some applications for these superpotenciais, with emphasis on a representation of the supersymmetric ammonia molecule and, in particular, we show that a system generated by the superpotential x-1/x, widely studied in the literature, can be solved more easily making use to the modular representation. We also seek for spectral solutions exact or approximated - of the partners Hamiltonians based on the exact ground state wave function of zero energy including the conventional x4 potential. The use of the variational method of functions coefficients. These methods, rarely used to date in the literature, allowed not only solve with excellent approximation the first levels of the system under study, but also proved the supersymmetry of the modular system. The results were compared with others found in the literature. We also show that for supersymmetric quantum systems, the Schroedinger equation can be put in a form of the Sturm-Liouville equation, and so, orthogonal polynomials solutions can be find through a weight-function generated by the superpotential. A brief overview of the PTsymmetry of the system directly involving a modular model proposed was also investigated, and we show that this system is equivalent to the non-Hermitian Hamiltonian one with potential V (z) = z4.

During criminal investigations involving firearms, the detection of gunshot residues (GSRs) is one of the most important evidences. In the present study, a new method to identify trace evidences of GSRs, deposited around the bullet entrance hole, in different types of fabrics used as targets, is described. The experiments were carried out using a 0.38-inch caliber revolver, and 9-mm and 0.40-inch caliber pistols. Testimonies of 2.25 cm(2) of the fabrics were cut around the bullet entrance and digested with 10% nitric acid. Antimony, barium, and lead were analyzed in the remaining solution using a sector field inductively coupled plasma mass spectrometer. The concentrations of the elements were detected at levels up to few microgram per square centimeter. The use of ternary graphics allowed us to identify specific patterns of distribution for blank samples and the clear distinction between the revolver and pistols used.

The drug trafficking is one of the most serious problems related to the Public Safety in Brazil, especially in the most populous areas of the country, as is the case of the city of Sao Paulo. In this work, it was developed a methodology that can help tracking the traffic routes of marijuana samples seized in the city of Sao Paulo, based on stable carbon and nitrogen isotopes, which are related to the climate and plant growth conditions. A model to classify the origin of unknown samples was built using linear discriminant analysis based on about 150 samples apprehended in the main producing regions of the country. Results for 76 samples seized in the city of Sao Paulo showed that most of them were cultivated in a humid region with the same origin as those from Mato Grosso do Sul. The provenance of 13 outliers samples from Northeast region (an important producing region) also were evaluated and some of them presented same profile of those from Mato Grosso do Sul, pointing to the existence of the traffic routes between the Northeast and Midwest region, probably as a consequence of the intensive field raids by Brazilian Federal Government since 1999.

The stable carbon and nitrogen isotopic ratios were measured in marijuana samples (Cannabis sativa L.) seized by the law enforcement officers in the three Brazilian production sites: Pernambuco and Bahia (the country's Northeast known as Marijuana Polygon), Para (North or Amazon region) and Mato Grosso do Sul (Midwest). These regions are regarded as different with respect to climate and water availability, factors which impact upon the isotope fractionations of these elements within plants. It was possible to differentiate samples from the dry regions (Marijuana Polygon) from those from Mato Grosso do Sul and Para, that present heavier rainfall. The results were in agreement with the climatic conditions of the suspected regions of origin and this demonstrates that seized samples can be used to identify the isotopic signatures of marijuana from the main producing regions in Brazil.

This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries.

As agressões ao meio ambiente, num contexto de esgotamento de recursos naturais, vêm recebendo crescente importância aos olhos da sociedade e, nesse cenário, o meio ambiente passou a ser protegido pelo Direito Penal. Assim, muitas destas agressões, como a poluição, passaram a ser qualificadas como crimes ambientais tornando se necessária a produção de prova técnica para o seu devido julgamento. Este trabalho apresenta uma nova estratégia para caracterização de crimes ambientais de poluição e correlatos baseado em abordagem multiparamétrica. Para isso foram utilizadas análises de diferentes parâmetros como metais, razões de isótopos estáveis e compostos orgânicos (hidrocarbonetos aromáticos policíclicos), e análise estatística multivariada, com o intuito de obter uma assinatura química robusta dos poluentes da fonte suspeita e assim estabelecer correspondência com os mesmos parâmetros determinados no compartimento ambiental receptor. Ainda, foram incorporados alguns conceitos de metrologia, como o cálculo de incerteza de amostragem, conforme preceituam as novas tendências de desenvolvimento conceitual e metodológico das ciências forenses. Os sedimentos de um curso dágua altamente impactado por descargas diversas foram o objeto das investigações como sendo o compartimento receptor e o percolado de um aterro de resíduos industriais perigosos envolvido em um crime ambiental foi analisado como possível fonte. A abordagem multiparamétrica utilizada neste trabalho proporcionou uma melhor discriminação dos pontos de coleta com base na sua localização com relação às fontes de poluição por meio da Análise de Componentes Principais e as análises de metais realizadas nos sedimentos permitiram caracterizar um crime de poluição ambiental. As estimativas de incerteza de amostragem evidenciaram variações nos resultados principalmente decorrentes da heterogeneidade da distribuição dos contaminantes no meio o que implica que as incertezas devem, preferencialmente, ser estimadas e reportadas nas medições no âmbito forense para um efetivo apoio às tomadas de decisões nelas baseadas. The aggressions to the environment in a context of depletion of natural resources have been receiving increasing attention in the eyes of society; therefore, the environment became protected by criminal law. For this reason, many assaults, such as pollution, were classified as environmental crimes, generating the need for scientific evidence to be used in the due judgment of these crimes. This paper presents a new method for characterization of environmental pollution and related crimes based on a multiparameter approach. This approach employs the analysis of different parameters such as metals, stable isotope ratio and organic compounds such as polycyclic aromatic hydrocarbons, and statistical techniques of multivariate analysis in order to obtain a robust chemical signature of the suspected source pollutants and then establish correspondence with the same parameters determined in the affected environmental compartment. In addition, some concepts of metrology were incorporated, such as uncertainty of sampling, as demanded by the conceptual and methodological trends in the development of forensic sciences. Watercourse sediments highly impacted by various discharges were investigated as the pollution sink and the leachate from a landfill of hazardous industrial waste involved in an environmental crime was analyzed as a possible source. The multiparameter approach used in this study provided a better discrimination of sampling points based on their location with respect to sources of pollution with the principal components analysis. The metal analysis in sediments allowed the characterization of a pollution crime in the studied stream. The estimates of uncertainty of sampling showed large variations in the results mainly arising from the heterogeneity of the distribution of contaminants in the environment. Hence, the uncertainties should preferably be estimated and reported in the forensic measurements to provide an effective support to decision making.