Consequences of COVid-19 in Latin American dentists in the first year of the pandemic, the period prior to vaccination campaigns.

Objectives: The aim of this investigation was to assess the impact of the COVID-19 pandemic on dentists in Latin America during the initial year of the outbreak, specifically within the timeframe preceding vaccination campaigns. This study determined the various facets in which dentists were affected and exactly what proportion of them was harmed. Methods: A comprehensive 33 question survey was distributed across 19 Latin American countries after the first year of the COVID-19 pandemic's presence in the region. Results: There was an absence of statistically significant differences in responses among the surveyed countries in Latin America, with the exception of four questions out of the total 33. Some relevant findings of Latin American were: one in three dental professionals experienced discrimination based on their occupation. Concurrently, three out of four dentists reported initiating new activities to lessen discomfort. Notably, 8.63 % of respondents sought assistance from a psychologist or psychiatrist, while 17.71 % resorted to the consumption of psychoactive substances within the first year of the pandemic.Furthermore, 7.28 % of the professionals indicated that they still had not obtained all the necessary personal protective equipment for their work and 92.05 % disclosing that they personally financed these essential resources. A certain percentage of dentists stated that the quality of care decreased due to the implementation of the new safety measures (40.03 %) or due to their own feelings during patient interactions (23.11 %). Lastly, 38.85 % of dentists contemplated leaving the profession. Conclusions: The impact of the COVID-19 pandemic on dentists was decidedly adverse, manifesting both in personal and professional fields, despite the diverse measures undertaken by these professionals to mitigate its effects.

Antigens to detect the acute phase of toxoplasmosis in pregnant women: standardized comparison.

A key element in any diagnostic technique is the antigen (Ag), a biomarker, but this is usually a protein that has a function to the parasite. Some biological aspects of the Ags and of the Toxoplasma gondii can influence the effectiveness of the diagnosis, as well as the antibody isotype and the characteristics of the assay. A large number of papers have assessed different proteins to distinguish the phases of infection, but the 'indices of effectiveness' differ among reports. This work presents for the first time a summary of all the Ags that have been evaluated, with standardized measurements of sensitivity and specificity. These values were calculated with information presented in the papers on Ag evaluations to differentiate the infection phases.

Semiquantitative Dot Blot with the GRA8 antigen to differentiate the stages of toxoplasmosis infection.

In this work we present a novel methodology to differentiate the phases of toxoplasmosis infection: the "semiquantitative Dot Blot". It is a simple technique that does not require expensive equipment, does not involve a long technique development, and can be used in a low-complexity laboratory. In this study, two recombinant sequences of Toxoplasma gondii GRA8 antigen were used, and specific IgG antibodies were detected in selected patient samples. This method makes it possible to obtain a score for each serum and define whether the patient is in the acute or chronic phase of the infection. The sensitivity and specificity results varied depending on the antigenic sequence used. With GRA8A, 62.1% and 72.7% were obtained, while with GRA8B, 82.8% and 72.1% were obtained, respectively. Although the sensitivity and specificity values were not close to 100%, they were similar to those reported with the same antigens in ELISA. Therefore, this quantitative technique would be a good alternative to ELISA.

Bacillus subtilis biofilm extends Caenorhabditis elegans longevity through downregulation of the insulin-like signalling pathway.

Beneficial bacteria have been shown to affect host longevity, but the molecular mechanisms mediating such effects remain largely unclear. Here we show that formation of Bacillus subtilis biofilms increases Caenorhabditis elegans lifespan. Biofilm-proficient B. subtilis colonizes the C. elegans gut and extends worm lifespan more than biofilm-deficient isogenic strains. Two molecules produced by B. subtilis - the quorum-sensing pentapeptide CSF and nitric oxide (NO) - are sufficient to extend C. elegans longevity. When B. subtilis is cultured under biofilm-supporting conditions, the synthesis of NO and CSF is increased in comparison with their production under planktonic growth conditions. We further show that the prolongevity effect of B. subtilis biofilms depends on the DAF-2/DAF-16/HSF-1 signalling axis and the downregulation of the insulin-like signalling (ILS) pathway.

Immunochemical evaluation of two Toxoplasma gondii GRA8 sequences to detect acute toxoplasmosis infection.

In this work, two Toxoplasma gondii GRA8 protein sequences were tested by indirect ELISA and measurement of avidity to differentiate between acute and chronic toxoplasmosis infection. Using the antigen called GRA8B, 79.7% sensitivity and 84.1% specificity was achieved detecting IgG concentrations and a 71.2% sensitivity and a 68.3% specificity detecting IgA concentrations. This study is the first to report IgA detection with GRA8 by ELISA to differentiate stages of infection. Unfortunately the indirect ELISA to detect IgM was not effective in distinguishing stages. Also, this work is the first to report that the GRA8 protein can aid the differentiation between acute and chronic phase infection by measuring IgG antibody avidity, a technique in which we obtained 85.71% and 100% of sensitivity and specificity, respectively. Finally, in silico tools were used to explain the differences in our immunochemistry results.