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Highlights • RT-PCR followed by CT shows high sensitivity for detecting COVID-19 • Immunological tests should use a combination of IgG and IgM • The genes E and RdRp present high analytical sensitivity to detect the virus • Assays for molecular diagnosis should employ two-target systems • Studies of diagnostic tests for COVID-19 are of moderate methodological quality, Objective . To collate the evidence on the accuracy parameters of all available diagnostic methods for detecting SARS-CoV-2. Methods . A systematic review with meta-analysis was performed. Searches were conducted in Pubmed and Scopus (April 2020). Studies reporting data on sensitivity or specificity of diagnostic tests for COVID-19 using any human biological sample were included. Results . Sixteen studies were evaluated. Meta-analysis showed that computed tomography has high sensitivity (91.9% [89.8–93.7%]), but low specificity (25.1% [21.0–29.5%]). The combination of IgM and IgG antibodies demonstrated promising results for both parameters (84.5% [82.2%-86.6%]; 91.6% [86.0%-95.4%], respectively). For RT-PCR tests, rectal stools/swab, urine, and plasma were less sensitive while sputum (97.2% [90.3–99.7%]) presented higher sensitivity for detecting the virus. Conclusions . RT-PCR remains the gold standard for the diagnosis of COVID-19 in sputum samples. However, the combination of different diagnostic tests is highly recommended to achieve adequate sensitivity and specificity.

This paper presents the degradation of the most widely used antibiotics for the treatment of tuberculosis, isoniazid (INH), by Fenton, photo-Fenton on bench-scale, and solar photo–Fenton on a pilot scale. The INH dosage in tuberculosis treatment varies according to disease stage, between 300–400 mg d-1patient-1, and its excretion range via urine is 50–70% within 24 h. The photodegradation processes were performed with 25 mg L-1 of INH, 10 mg of Fe2+, and 125 mg L–1 of H2O2 for 120 min. The degradation of INH was monitored by HPLC–DAD and dissolved organic carbon (DOC). The degradation by-products were analyzed by UPLC QToF-MS and the toxicity was evaluated by Daphnia magna (acute toxicity) and Lactuca sativa (phytotoxicity). INH removal was higher than 99% at 60 min for Fenton, 10 min for photo-Fenton, and 15 min for solar photo–Fenton. The DOC results indicated that under light irradiation (photo–Fenton and solar photo–Fenton), the mineralization rate was > 70%. The nitrite ion analysis indicated the complete oxidation of nitrogen. Besides the main INH degradation by-products, isonicotinic acid, isonicotinamide, and N'-(pyridyl-4-carbonyl)-hydrazide, we detected four unknown by-products by mass spectrometry. The Fenton treatment decreased the toxicity of D. magna by 75% in 15 minutes, achieving 87% in 60 minutes of treatment, while the photo–Fenton process conducted with artificial radiation reduced 87% of the toxicity of D. magna and resulted in no significant effect in L. sativa seeds in 15 minutes (QUV-A 1.29 kJ L-1). However, solar photo-Fenton (QUV-A 3.38 kJ L–1) did not reduce toxicity.

This systematic review (number register: CRD42018112736) was performed to compare the sensitivity and specificity of leprosy diagnostic methods. The search was conducted in 3 electronic databases in January 2021. Studies evaluating leprosy diagnostic tests were included according the eligibility criteria. Meta-analysis was performed to calculate the sensibility and specificity of the groups. We included 36 studies. The test sensitivity for paucibacillary patients was 0.31 (95%CI: 0.29-0.33) and the specificity was 0.92 (95%CI: 0.92-0.93). In multibacillary patients, the sensitivity was 0.78 (95%CI: 0.77-0.80) and specificity was 0.92 (95%CI: 0.92-0.93). Comparing the sensitivity and specificity of the different techniques included, it should be noted that polymerase chain reaction (PCR) test presented the highest sensitivity for paucibacillary patients, while the western blot technique showed the highest sensitivity for multibacillary patients. However, further studies are needed to optimise the diagnosis of leprosy, requiring research with a larger number of samples and more uniform protocols.

The bioaccessibility of bioactive compounds were increased in white and green teas that are normally degraded due to the adverse conditions of the human gastrointestinal system. The hypothesis was that the association of tea extracts with Saccharomyces cerevisiae during the biosorption process would protect bioactive compounds, making them more bioaccessible. Different treatments with yeast and extracts with pH changes were tested to assess whether there was an improvement in biosorptive capacity, which, occurred with alkaline treatments. Colorimetric analysis showed that >50% of the phenolic compounds from both extracts were biosorbed on yeast. This was consistent with the results using mass spectrometry and mid-infrared spectroscopy analyses. The in vitro gastrointestinal digestion test showed that bioaccessibility was higher in biosorbed yeasts than in pure extract (38% for white tea and 61% for green tea), which confirms the viability and potential of this application.

Great efforts have been made to increase the bioaccessibility of bioactive compounds from plant sources. This can be achieved by the innovative and effective method of biosorption of these compounds in Saccharomyces cerevisiae obtained from the industrial fermentative process (waste yeast). In this context, this research evaluated if chemical modifications of depleted yeast can improve the capacity to biosorb the phenolic compounds and if through in vitro digestion tests, this approach can increase bioaccessibility of the secondary metabolites from yerba mate. The results showed that the chemical modification of the yeast promoted an increase in the biosorption efficiency of the bioactive compounds. Mass spectrometry peaks for the phenolic compounds reduced after biosorption as observed for the caffeic and dicaffeoylquinic acids and for kaempferol and rutin. In addition, a 10% reduction of caffeine was verified after biosorption, quantified by mass spectrometry chromatography. This showing that the compounds were retained in the cells, which was also observed by an increase of cell turgidity with scanning electron microscopy (SEM). Mid-infrared spectroscopy showed that the major bands related to the components of the compounds increased proportionally after biosorption. Furthermore, an increase of bioaccessibility of the yerba mate bioactive compounds adsorbed in S. cerevisiae was verified when compared with the crude extract.