RESUMEN
A strictly defined subset of gonococci (n = 65) isolated in Italy from 2011 to 2014 was characterized by antimicrobial susceptibility for cefixime (CFM) and ceftriaxone (CRO) and by sequencing of resistance determinant genes (penA, mtrR, porB1b, ponA) for extended-spectrum cephalosporins and Neisseria gonorrhoeae multiantigen sequence typing (NG-MAST). The penA mosaic alleles XXXIV and XXXV were found in all resistant (R) and decreased susceptibility (DS) gonococci to CFM, except for one. They were associated with an adenine deletion in the mtrR promoter plus amino acid substitutions, H105Y or G45D, in the coding region and ponA L421P. The penA mosaic allele XXXIV, and one variant, was found exclusively among genogroup (G) 1407 and its closely related sequence types (STs), as in CFM-DS as well as in CFM-R isolates. Single or combined mutation patterns in penA, mtrR, porB1b, and ponA genes were associated with different CFM susceptibility patterns and NG-MAST STs. Genotyping and antimicrobial resistance (AMR) determinant analyses can be valuable to enhance the gonococcal AMR surveillance.
Asunto(s)
Antibacterianos/uso terapéutico , Cefixima/uso terapéutico , Farmacorresistencia Bacteriana/genética , Gonorrea/tratamiento farmacológico , Gonorrea/microbiología , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/genética , Alelos , Sustitución de Aminoácidos/genética , Proteínas Bacterianas/genética , Ceftriaxona/uso terapéutico , Cefalosporinas/uso terapéutico , Genotipo , Humanos , Italia , Pruebas de Sensibilidad Microbiana/métodos , Mutación/genética , Neisseria gonorrhoeae/aislamiento & purificación , Regiones Promotoras Genéticas/genéticaRESUMEN
One challenge in biology is signal transduction monitoring in a physiological context. Intravital imaging techniques are revolutionizing our understanding of tumor and host cell behaviors in the tumor environment. However, these deep tissue imaging techniques have not yet been adopted to investigate the second messenger calcium (Ca²âº). In the present study, we established conditions that allow the in vivo detection of Ca²âº signaling in three-dimensional tumor masses in mouse models. By combining intravital imaging and a skinfold chamber technique, we determined the ability of photodynamic cancer therapy to induce an increase in intracellular Ca²âº concentrations and, consequently, an increase in cell death in a p53-dependent pathway.