Consumo de substâncias psicoativas por adolescentes escolares de Ribeirão Preto, SP (Brasil). I - Prevalência do consumo por sexo, idade e tipo de substância The consumption of psychoactive substances by adolescents in schools in an urban area of Southeastern region of Brazil. I - Prevalence by sex, age and kind of substance

INTRODUÇÃO: A preocupação suscitada quanto ao consumo de substâncias psicoativas pelos adolescentes tem mobilizado grandes esforços em todo o mundo na produção de conhecimento sobre este fenômeno. Decidiu-se estudar as taxas de prevalência de consumo de substâncias psicoativas de uso lícito e ilícito, sua distribuição por idade, sexo e a idade da primeira experiência com essas substâncias, entre adolescentes escolares do Município de Ribeirão Preto, SP, Brasil. MATERIAL DE MÉTODO: Um questionário devidamente adaptado e submetido a um teste de confiabilidade foi auto-aplicado a uma amostra proporcional de 1.025 adolescentes matriculados na oitava série do primeiro grau e primeiro, segundo e terceiro anos do segundo grau, das escolas públicas e privadas do município estudado. O questionário continha questões sobre o uso de dez classes de substâncias psicoativas, questões demográficas e informações de validação, além de questões de percepção e comportamento intrínseco ao consumo de drogas. RESULTADOS: Da amostra 88,9% consumiram bebidas alcoólicas alguma vez na vida; 37,7% utilizaram o tabaco; 31,1% os solventes; 10,5% os medicamentos; 6,8% a maconha; 2,7% a cocaína; 1,6% os alucinógenos e 0,3% consumiu alguma substância a base de opiácios. As taxas de consumo cresceram com a idade, para todas as substâncias; no entanto, o uso de tabaco e de substâncias ilícitas mostrou uma desaceleração nos anos que compreendem o final da adolescência. Verificou-se que os meninos consumiram mais do que as meninas, exceto para os medicamentos, com as meninas consumindo barbitúricos, anfetaminas e tranqüilizantes em proporções semelhantes ou maiores que os meninos. A idade da primeira experiência mostrou que o acesso às substâncias psicoativas ocorreu em idades bastante precoces. CONCLUSÕES: As substâncias psicoativas, sejam lícitas ou ilícitas, são freqüentemente experimentadas na adolescência, tanto pelos meninos como pelas meninas, muitas vezes em idades bem precoces.<br>INTRODUCTION: Concern over the consumption of psychoactive substances by teenagers has given rise to a great wordwide effort to produce information about this phenomenon. This study set out to investigate the prevalence of consumption of legal and illegal psychoactive substances, its distribution by age, sex and age at first experience of them, among teenage pupils in county, Ribeirão Preto, SP, Southeastern Brazil. MATERIAL AND METHOD: A self-applicable questionnaire duly adapted and submitted to a reliability test was applied to a proportional sample of 1,025 teenagers enrolled in 8th, 9th, 10th and 11th grads at public and private city schools. The questionnaire contained questions about the use of ten classes of psychoactive substances, demographic questions and validation information, as well as questions about the perception and intrinsic behavior related to drug consumption. RESULTS: The sample of 88.9% had consumed alcoholic beverages sometime in their lives, 37.7% had used tobacco, 31.1% solvents, 10.5% medicines, 6.8% marihuana, 2.7% cocaine, 1.6% hallucinogens, and 0.3% of the sample had consumed some opiate substance. The rates of consumption increased with age for all substances; however, the use of tobacco and of illegal substances was less intense during the later years of adolescence. As to sex distribution, boys consumed more than girls, except for medicines, with girls consuming barbiturates, amphetamines and tranquilizers in proportions similar to or higher than those observed among boys. Age at first experience showed that access to psychoactive substances occurred at very early ages. CONCLUSIONS: Experimenting with psychoactive substances, whether legal or illegal, is a frequent phenomenon during adolescence, both among boys and girls, often at very early ages

North American Glyptodontines (Xenarthra, Mammalia) in the Upper Pleistocene of northern South America

The Glyptodontidae is one of the most conspicuous groups in the Pleistocene megafauna of the Americas. The Glyptodontinae were involved in the Great American Biotic Interchange (GABI) and their earliest records in North America are about 3.9 Ma, suggesting an earlier formation of the Panamanian landbridge. Taxonomically it is possible to recognize two Pleistocene genera of Glyptodontinae:Glyptodon (ca. 1.8 – 0.008 Ma), restricted to South America, andGlyptotherium (ca. 2.6 – 0.009 Ma), including records in both North and Central America. Here we present the first report of the genusGlyptotherium in South America, from the Late Pleistocene of several fossil localities in Falcón State, northwestern Venezuela. A comparative analysis of the material, represented by cranial and postcranial parts, including the dorsal carapace and caudal rings, suggests a close affinity withGlyptotherium cylindricum (Late Pleistocene of Central Mexico). This occurrence in the latest Pleistocene of the northernmost region of South America Supports the bidirectional faunal migration during the GABI and the repeated re-immigration from North America of South American clades, as has been reported in other members of the Cingulata (e.g., Pampatheriidae)