RESUMO
Hearing loss is highly prevalent with a worldwide incidence of 1-2 per 1000 newborns. Several previous studies have demonstrated that mutations of connexin 26 (Cx26 or GJB2) are responsible for most cases of the recessive non-syndromic sensorineural hearing loss (NSSHL). Certain mutations have been described frequently among various populations, which include 35delG, 167delT, and 235delC. Recently, a missense mutation, V37I, was reported as a pathogenic change in East Asian affected individuals. To identify genetic variants associated with NSSHL in Thai population, we performed mutation analysis of Cx26 in 166 unrelated probands with NSSHL and 205 controls. We identified seven novel genetic variants in Cx26. We also identified a high prevalence of the V37I mutation among both affected probands (11.1%) and control subjects (8.5%), which suggests that the pathologic role of V37I may be modified by other genes. Our data support previous studies that show heterogeneity in the frequencies and types of mutations in Cx26 within populations and among ethnicities and that before clinical significance and causality can be attributed to a genetic variant, functional characterization is necessary.
Assuntos
Povo Asiático/genética , Conexinas/genética , Perda Auditiva Neurossensorial/genética , Mutação de Sentido Incorreto/genética , Adolescente , Substituição de Aminoácidos/genética , Criança , Pré-Escolar , Conexina 26 , Feminino , Perda Auditiva Neurossensorial/etnologia , Humanos , Lactente , Isoleucina/genética , Masculino , Prevalência , Tailândia , Valina/genéticaRESUMO
The susceptibility of 424 bacterial isolates causing diarrhoea were tested by agar dilution technique on Mueller-Hinton Agar against amoxicillin, ampicillin, ceftriaxone, chloramphenicol, co-trimoxazole, ciprofloxacin, doxycycline, norfloxacin and ofloxacin. The bacterial species included were Aeromonas hydrophila, Edwardsiella tarda, Pleisomonas shigelloides, Salmonella spp., Shigella spp., Vibrio cholerae and Vibrio parahaemolyticus. The most active compounds were the fluorinated 4-quinolones studied, that is, ciprofloxacin, norfloxacin and ofloxacin, and ceftriaxone. The other antibacterial agents were considerably less active; a substantial portion of tested isolates were resistant to them.
