Calcinose Cutis, Insuficiência Renal e Heparinas de Baixo Peso Molecular Contendo Cálcio

Foi solicitada observação por Dermatologia de uma doente de 35 anos de idade, de raça negra, por 2 nódulos subcutâneos localizados na região paraumbilical direita e flanco direito com 2 semanas de evolução. Da história prévia, destaque para doença renal crónica em programa de hemodiálise e infeção pelo vírus da imunodeficiência humana (VIH-1). Ao exame objetivo observaram-se 2 nódulos bem delimitados, subcutâneos, sem alteração da coloração; à palpação, estes eram dolorosos, de consistência pétrea e não aderentes aos planos profundos. Foi realizada biópsia incisional para exame histopatológico, que confirmou a hipótese diagnóstica de calcinose cutis. Uma revisão cuidadosa de toda a medicação realizada permitiu estabelecer a relação entre este achado e a administração subcutânea de nadroparina cálcica nessa localização, umas semanas antes. A dermatose regrediu espontaneamente em 2 meses após a suspensão das injeções subcutâneas de nadroparina cálcica. A calcinose cutis devida à administração de heparinas de baixo peso molecular contendo cálcio é rara, admitindo-se que elevação do produto fósforo-cálcio possa ser determinante na sua fisiopatologia. É geralmente autolimitada, resolvendo espontaneamente.

Preparation of gas-filled porous microparticles (GPPs) and microbubbles (MBs) by PGSS method

Dissertation to obtain the Master Degree in Biotechnology

Transthyretin Amyloidosis: Chaperone Concentration Changes and Increased Proteolysis in the Pathway to Disease

Transthyretin amyloidosis is a conformational pathology characterized by the extracellular formation of amyloid deposits and the progressive impairment of the peripheral nervous system. Point mutations in this tetrameric plasma protein decrease its stability and are linked to disease onset and progression. Since non-mutated transthyretin also forms amyloid in systemic senile amyloidosis and some mutation bearers are asymptomatic throughout their lives, non-genetic factors must also be involved in transthyretin amyloidosis. We discovered, using a differential proteomics approach, that extracellular chaperones such as fibrinogen, clusterin, haptoglobin, alpha-1-anti-trypsin and 2-macroglobulin are overrepresented in transthyretin amyloidosis. Our data shows that a complex network of extracellular chaperones are over represented in human plasma and we speculate that they act synergistically to cope with amyloid prone proteins. Proteostasis may thus be as important as point mutations in transthyretin amyloidosis.

Molecular mechanisms of sexual development in basidiomycetes: exploring connections with lifestyles

Dissertação para obtenção do Grau de Doutor em Biologia

Leber Congenital Amaurosis: Comprehensive Survey of the Genetic Heterogeneity, Refinement of the Clinical Definition, and Genotype-Phenotype Correlations as a Strategy for Molecular Diagnosis

Leber congenital amaurosis (LCA) is the earliest and most severe form of all inherited retinal dystrophies, responsible for congenital blindness. Disease-associated mutations have been hitherto reported in seven genes. These genes are all expressed preferentially in the photoreceptor cells or the retinal pigment epithelium but they are involved in strikingly different physiologic pathways resulting in an unforeseeable physiopathologic variety. This wide genetic and physiologic heterogeneity that could largely increase in the coming years, hinders the molecular diagnosis in LCA patients. The genotyping is, however, required to establish genetically defined subgroups of patients ready for therapy. Here, we report a comprehensive mutational analysis of the all known genes in 179 unrelated LCA patients, including 52 familial and 127 sporadic (27/127 consanguineous) cases. Mutations were identified in 47.5% patients. GUCY2D appeared to account for most LCA cases of our series (21.2%), followed by CRB1 (10%), RPE65 (6.1%), RPGRIP1 (4.5%), AIPL1 (3.4%), TULP1 (1.7%), and CRX (0.6%). The clinical history of all patients with mutations was carefully revisited to search for phenotype variations. Sound genotype-phenotype correlations were found that allowed us to divide patients into two main groups. The first one includes patients whose symptoms fit the traditional definition of LCA, i.e., congenital or very early cone-rod dystrophy, while the second group gathers patients affected with severe yet progressive rod-cone dystrophy. Besides, objective ophthalmologic data allowed us to subdivide each group into two subtypes. Based on these findings, we have drawn decisional flowcharts directing the molecular analysis of LCA genes in a given case. These flowcharts will hopefully lighten the heavy task of genotyping new patients but only if one has access to the most precise clinical history since birth.

Clinical and Molecular Characterization of Diastrophic Dysplasia in the Portuguese Population

SLC26A2-related dysplasias encompass a spectrum of diseases: from lethal achondrogenesis type 1B (ACG1B; MIM #600972) and atelosteogenesis type 2 (AO2; MIM #256050) to classical diastrophic dysplasia (cDTD; MIM #222600) and recessive multiple epiphyseal dysplasia (rMED; MIM #226900). This study aimed at characterizing clinically, radiologically and molecularly 14 patients affected by non-lethal SLC26A2-related dysplasias and at evaluating genotype-phenotype correlation. Phenotypically, eight patients were classified as cDTD, four patients as rMED and two patients had an intermediate phenotype (mild DTD - mDTD, previously 'DTD variant'). The Arg279Trp mutation was present in all patients, either in homozygosity (resulting in rMED) or in compound heterozygosity with the known severe alleles Arg178Ter or Asn425Asp (resulting in DTD) or with the mutation c.727-1G>C (causing mDTD). The 'Finnish mutation', c.-26+2T>C, and the p.Cys653Ser, both frequent mutations in non-Portuguese populations, were not identified in any of the patients of our cohort and are probably very rare in the Portuguese population. A targeted mutation analysis for p.Arg279Trp and p.Arg178Ter in the Portuguese population allows the identification of approximately 90% of the pathogenic alleles.

Ocorrência, diagnóstico molecular e resistência a antifúngicos de Candida sp. de infecções vaginais em Portugal e Cabo-Verde

Dissertação para a obtenção do Grau de Mestre em Genética Molecular e Biomedicina

Weekly tracking of stability of the flow of conversations into the subprocesses of the Last Planner System

21st Annual Conference of the International Group for Lean Construction – IGLC 21 – Fortaleza, Brazil

Moluscos hospedeiros intermediários de tremátodes: Estudo molecular de helisoma sp. (Gastropoda: planorbidae) de diferentes áreas geográficas

Ao longo dos tempos a caracterização das diferentes espécies da classe Gastropoda baseava-se apenas em características fenotípicas (morfologia da concha e partes moles), as quais eram insuficientes para distinguir espécies e subespécies. Assim, a caracterização genética desenvolvida nos últimos anos, tem-se mostrado uma boa ferramenta aplicada á diferenciação molecular de espécies, permitindo uma melhor compreensão sobre moluscos com um importante papel como hospedeiros intermediários de tremátodes e qual a sua posição dentro da família Planorbidae. Os objectivos deste trabalho foram, por um lado fazer um estudo comparativo de populações de Helisoma sp., de Portugal e Cabo Verde, baseado num estudo molecular utilizando marcadores moleculares, nomeadamente o gene COI do DNA mitocondrial (mtDNA) e o gene 16S do RNA ribossomal (rRNA) e a região interna transcrita (ITS) do DNA ribossomal, e recorrendo à técnica PCR-RFLP, direccionada para a região ITS para a identificação de possíveis polimorfismos e, por outro lado estabelecer uma relação filogenética entre as populações portuguesas e cabo verdianas de Helisoma e outros planorbideos, hospedeiros intermediários de tremátodes. Os resultados obtidos, para os genes em análise permitiram a identificação de três regiões distintas: Cabo Verde, Madeira e Portugal Continental, esta última formada pelas amostras de Algarve e Coimbra, apesar da distante geográfica que separa cada umas destas duas áreas. Os resultados obtidos para os genes COI e 16S e para a região ITS, mostraram uma elevada homologia com as espécies Helisoma trivolvis e H. duryi.

Medicago truncatula as a platform for Molecular Farming: a study of the subcellular localization of a human recombinant protein!

Dissertation presented at Faculdade de Ciências e Tecnologia of Universidade Nova de Lisboa to obtain the Degree of Master in Biotecnology