Evolution of gallium applications in medicine and microbiology: a timeline.

Characterized as a semi-metal, gallium is a chemical element not found freely in the environment, but extracted as a by-product from other minerals. Despite of this, there are several gallium compounds with various applications, such as in the production of semiconductors, light emitting diodes; commercially as a potential cost reducer; pharmacology as cancer-related hypercalcemia, non-Hodgkin' lymphoma, breast and bladder cancer mainly and antimicrobial treatments. The latter will be emphasized in this work due to the contemporary emergence of the development of compounds with antimicrobial potential as a result of the spread of multidrug-resistant bacteria. So, this article discusses the main works, from the discovery of gallium to those that culminated in the current research in microbiology of the last two decades. The antimicrobial activity of gallium can be confirmed through the experimental data and be a promising mean to other investigations, especially due to its iron mimicry ability and the capacity to disrupt microorganisms' metabolism.

A highly specific and sensitive nanoimmunosensor for the diagnosis of neuromyelitis optica spectrum disorders.

A precise diagnosis for neuromyelitis optica spectrum disorders (NMOSD) is crucial to improve patients' prognostic, which requires highly specific and sensitive tests. The cell-based assay with a sensitivity of 76% and specificity of 100% is the most recommended test to detect anti-aquaporin-4 antibodies (AQP4-Ab). Here, we tested four AQP4 external loop peptides (AQP461-70, AQP4131-140, AQP4141-150, and AQP4201-210) with an atomic force microscopy nanoimmunosensor to develop a diagnostic assay. We obtained the highest reactivity with AQP461-70-nanoimunosensor. This assay was effective in detecting AQP4-Ab in sera of NMOSD patients with 100% specificity (95% CI 63.06-100), determined by the cut-off adhesion force value of 241.3 pN. NMOSD patients were successfully discriminated from a set of healthy volunteers, patients with multiple sclerosis, and AQP4-Ab-negative patients. AQP461-70 sensitivity was 81.25% (95% CI 56.50-99.43), slightly higher than with the CBA method. The results with the AQP461-70-nanoimmunosensor indicate that the differences between NMOSD seropositive and seronegative phenotypes are related to disease-specific epitopes. The absence of AQP4-Ab in sera of NMOSD AQP4-Ab-negative patients may be interpreted by assuming the existence of another potential AQP4 peptide sequence or non-AQP4 antigens as the antibody target.