Argilas modificadas como catalisadores ácidos sólidos

Important bentonitic deposits are present in Porto Santo Island, part of the Madeira Archipelago. Several locations were selected and samples were collected and characterised. The bentonite obtained at Serra de Dentro (SD) was selected for further laboratorial work. The fine fraction of SD bentonite was purified using several methods and the sodium homoionic form was prepared. This was the starting material used in the three generic types of modifications: metal exchange, acid activation and pillaring. These modifications produce materials with markedly different acidic (e.g. Brönsted and/or Lewis acidity), textural (e.g. increase of the surface area and active site accessibility) or structural (e.g. creation of permanent porous structures) properties. The wide range of materials obtained (including reference clays counterparts) was characterised in terms of chemical, structural, textural and catalytic properties. Limonene is an important raw material produced in Portugal, and its aromatisation reaction was chosen for the catalytic characterisation of the clay catalysts prepared.Orientadores: Paula Castilho e Christopher Bree

Clinicopathological study of patients with head and neck sarcomas Avaliação clínico-patológica de pacientes com sarcomas em cabeça e pescoço

Sarcomas are rare tumors, mainly stemming from the embryonic mesoderm, with a high grade of morbidity and mortality. OBJECTIVE: To carry out a retrospective study of head and neck sarcoma cases between 1999 and 2008 in three specialized centers in the city of Fortaleza. MATERIALS AND METHODS: Data collection was based on the charts of the patients in the study. For statistical analysis purposes we used the chi-square associations and the z test for proportions. RESULTS: We found records of 36 patients, and the most affected ones were adult brown males, in the age range between 20 and 59 years - mean age of 39.7. The man/woman ratio was 1.76:1. The most prevalent histological type was the rhabdomyosarcoma and their most common locations were the face and the neck. Most of the sample was made up of live patients without evidence of the disease in the last visit - 41.6% of the cases. The most common treatment modes were the combination of surgery + radiotherapy + chemotherapy and surgery + radiotherapy, with 27.8% of the cases each. CONCLUSION: Sarcomas have a great histological variability and may have numerous locations. Since these are rare and not well-known lesions, new epidemiological studies must be carried out in order to enhance our understanding of the disease.<br>Sarcomas são tumores raros originados predominantemente do mesoderma embrionário e que apresentam elevado grau de morbidade e mortalidade. OBJETIVO: Realizar estudo retrospectivo dos casos de sarcomas em cabeça e pescoço no período de 1999 a 2008 em três centros especializados. MATERIAL E MÉTODO: A coleta de dados teve base nos prontuários dos pacientes estudados. Para análise estatística, foram utilizados os testes de associações qui-quadrado e o teste z para proporções. RESULTADO: Foram encontrados registros de 36 pacientes, sendo os indivíduos mais acometidos homens adultos, da raça parda, na faixa etária de 20 a 59 anos, com idade média de 39,7. A relação homem/mulher foi de 1,76:1. O tipo histológico mais prevalente foi rabdomiossarcoma e as localizações mais comuns foram face e região cervical. A maior parte da amostra foi de pacientes vivos sem evidência de doença na última consulta, com 41,6% dos casos. As formas mais comuns de tratamento foram a combinação de cirurgia+radioterapia+quimioterapia e cirurgia + radioterapia, com 27,8% dos casos cada. CONCLUSÃO: Os sarcomas apresentam grande variedade histológica e podem acometer diversas localizações. Por se tratar de lesões raras e pouco conhecidas, novos estudos epidemiológicos devem ser realizados para que se aumente o conhecimento sobre a doença