Evaluation of the GeneXpert MTB/RIF to diagnose tuberculosis in a public health laboratory.

Objectives: To evaluate the performance of geneXpert MTB/Rif versus conventional methods (bacilloscopy and culture) in the diagnosis of tuberculosis in a Central Public Health Laboratory (LACEN, Tocantins), Northern Brazil.

Methods: Retrospective study, with information from 1,973 suspected cases of tuberculosis from patients treated from January 2015 to December 2020.

Results: From the culture (reference standard), the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the geneXpert MTB/Rif were 100%, 97%, 74%, 100%, and 97%, respectively, against 85%, 98%, 80%, 98%, and 97% of bacilloscopy.

Neuropeptide Y expression in cutaneous melanoma.

Background: Neuropeptide Y (NPY) is widely found in the nervous system and has a role in numerous physiologic processes. In addition, NPY receptors are expressed in neuroendocrine tumors, breast cancer, prostate cancer, kidney cancer, and some types of sarcomas. Different neuropeptides, particularly α-melanocyte-stimulating hormone (MSH), seem to play a role in the pathogenesis of melanoma.