Laboratory diagnosis for Covid-19: A mini-review

Abstract Coronavirus disease (COVID-19) is a pandemic caused by a new coronavirus, called SARS-CoV-2. This disease was first identified in December 2019 and rapidly developed into a challenge to the public health systems around the world. In the absence of a vaccine and specific therapies, disease control and promotion of patient health are strongly dependent on a rapid and accurate diagnosis. This review describes the main laboratory approaches to making a diagnosis of COVID-19 and identifying those previously infected with SARS-CoV-2.

Detection of Drug Resistant Mycobacterium Tuberculosis Strains Using Kit SIRE Nitratase®: a Multicenter Study

Abstract (1) Background: The Commercial Kit SIRE Nitratase® PlastLabor, is a drug susceptibility test kit used to detect Mycobacterium tuberculosis resistance to first-line TB treatment drugs. The present study aimed at evaluating its performance in a multicenter study. (2) Methods: To determine its accuracy, the proportion methods in Lowenstein Jensen medium or the BACTECTMMGITTM960 system was used as a gold standard. (3) Results: The study revealed that the respective accuracies of the kit with 190 M. tuberculosis clinical isolates, using the proportion methods in Lowenstein Jensen medium or BACTECTMMGITTM960 system as a gold standard, were 93.9% and 94.6%, 96.9% and 94.6%, 98.0% and 97.8%, and 98.0% and 98.9%, for streptomycin, isoniazid, rifampicin, and ethambutol, respectively. (4) Conclusion: Thus, the kit can rapidly screen resistance to streptomycin, isoniazid, rifampicin, and ethambutol. Additionally, it does not require sophisticated equipment; hence, it can be easily used in the laboratories of low and middle income countries.

Initial antimicrobial activity studies of plants of the riverside forests of the southern Uruguay River / Estudos antimicrobianos preliminares de plantas da floresta ribeirinha do sul do rio Uruguai

Development of new antimicrobial compounds against different microorganisms is becoming critically important, as infectious diseases are still one of the leading causes of death in the world. Plants can be a useful source of these lead compounds. In this study, 66 extracts of 25 plants of the riverside forest of southern Uruguay River were studied for antimicrobial activity against Staphylococcus aureus, Listeria inocua, Escherichia coli, Pseudomonas aeruginosa, Mycobacterium tuberculosis, Aspergillus niger and Candida albicans. Fifty-three of these extracts showed some kind of antimicrobial activity. Six of these (Eugenia mansoni, Eugenia repanda, Myrcianthes cisplatensis, Paullinia ellegans, Petunia sp and Ruprechtia laxiflora) presented activity against Mycobacterium tuberculosis with MIC values as low as 50 μg/mL.

As doenças infecciosas ainda são uma das principais causas de morte no mundo, sendo de significativa importância o desenvolvimento de novos compostos antimicrobianos contra diferentes microrganismos. As plantas podem ser uma boa fonte para direcionar a busca destes compostos. Neste estudo, 66 extratos de 25 plantas da floresta ribeirinha do sul do Rio Uruguai foram estudados para a atividade antimicrobiana contra o Staphylococcus aureus, Listeria inocua, Escherichia coli, Pseudomonas aeruginosa, Mycobacterium tuberculosis, Aspergillus niger e Candida albicans. Cinqüenta e três destes extratos apresentaram algum tipo de atividade antimicrobiana. Seis (Eugenia mansoni, Eugenia repanda, Myrcianthes cisplatensis, Paullinia ellegans, Petunia sp e Ruprechtia laxiflora) apresentaram atividade contra o Mycobacterium tuberculosis com CIM de 50 μg/mL.