RESUMO
In the new age of PI3K inhibitors, the mutational status of PI3Kca oncogene in the Cavity Squamous Cell Carcinoma (OC-SCC) needs further analysis. It is the sixth most common cancer in the world. The aim of this study was to evaluate PI3Kca oncogene mutations and to correlate them with the clinical-histological characteristics of individuals presenting these tumors. We recruited 74 individuals with OC-SCC diagnosis (period 2000-2014). Histological sections were used. DNA was purified; PIK3ca gene exons 9 and 20 were amplified and sequenced. In 49/74 cases (66 %), the complete sequence of both codons was analyzed by Sanger method. We found that 7/49 (14 %) individuals mutated. In exon 9 we found 1/49 (2 %), and in exon 20 M1043I 8/49 (16 %). We have found the coexistence of more than one mutation in a same individual (E542 K and M1043I). A positive association was observed between the mutational status of the codon 9 (E542 K) and the tongue location. In conclusion, the frequency of PI3Kca gene mutation in OC-SCC was 16 %, which is similar to that reported for other populations. We found a mutation not previously described (M1043I) in this pathology. Should its biological effect be confirmed, it must be added to the list of PIK3ca mutations. Total mutations in the PIK3ca were 32 %, with tongue being the site at the greatest risk (E542K-E545K-M1043I). These findings would facilitate the identification of patients with therapeutic targets in the near future.
Assuntos
Carcinoma de Células Escamosas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Bucais/genética , Mutação/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Análise Mutacional de DNA/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
The pseudorotational motions of highly hydroxylated pentafuranose sugars in the free state and tethered to hydroxyapatite have been compared. The conformation pentafuranose ring remains restricted at the North region of the pseudorotational wheel, which is the one typically observed for nucleosides and nucleotides in the double helix A-RNA, when the phosphate-bearing sugar is anchored to the mineral surface. Results indicate that the severe restrictions imposed by the mineral are responsible of the double helix preservation when DNA and RNA are encapsulated in crystalline nanorods.
Assuntos
Durapatita/química , Monossacarídeos/química , RNA/química , Configuração de Carboidratos , Hidroxilação , Cinética , Modelos Moleculares , Conformação de Ácido Nucleico , Rotação , TermodinâmicaRESUMO
An imaging system using a 64-element array of PbS detectors has been successfully tested at Kitt Peak. The first images of the low contrast solar granulation at 1.65 micro have been obtained with a signal-to-noise ratio better than 200 and a resolution of the order of 1 see of arc. The problem of imaging systems for low contrast objects in the infrared is discussed.
