Background The first case of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in Rio Grande do Norte, northeastern Brazil, was diagnosed on March 12, 2020; thereafter, multiple surges of infection occurred, similar to what was seen elsewhere. These surges were mostly due to SARS-CoV-2 mutations leading to emergence of variants of concern (VoC). The introduction of new VoCs in a population previously exposed to SARS-CoV-2 or after vaccination has been a challenge to understanding the kinetics of the protective immune response against this virus. The aim of this study was to investigate the outbreak of SARS-CoV-2 reinfections observed in mid-January 2022 in Rio Grande do Norte state, Brazil. It describes the clinical and genomic characteristics of nine cases of reinfection that occurred coincident with the introduction of the omicron variant. Methodology/Principal findings Of a total of 172,965 individuals with upper respiratory symptoms tested for SARS-CoV-2, between March 2020 through mid-February 2022, 58,097 tested positive. Of those, 444 had documented a second SARS-CoV-2 infection and nine reinfection cases were selected for sequencing. Genomic analysis revealed that virus lineages diverged between primary infections and the reinfections, with the latter caused by the Omicron (BA.1) variant among individuals fully vaccinated against SARS-CoV-2. Conclusions/Significance Our findings suggest that the Omicron variant is able to evade both natural and vaccine-induced immunity, since all nine cases had prior natural infection and, in addition, were fully vaccinated, emphasizing the need to develop effective blocking vaccines.

CvL, a lectin from the marine sponge Cliona varians agglutinated type A papainized erythrocytes and was strongly inhibited by d-galactose and sucrose. Models of leukocyte migration in vivo were used to study the inflammatory activity of CvL through of mouse paw oedema and peritonitis. Effect of CvL on peritoneal macrophage activation was analysed. Effects of corticoids and NSAIDS drugs were also evaluated on peritonitis stimulated by CvL. Results showed that mouse hind-paw oedema induced by subplantar injections of CvL was dose dependent until 50 microg/cavity. This CvL dose when administered into mouse peritoneal cavities induced maxima cell migration (9283 cells/microL) at 24 h after injection. This effect was preferentially inhibited by incubation of CvL with the carbohydrates d-galactose followed by sucrose. Pre-treatment of mice with 3% thioglycolate increases the peritoneal macrophage population 2.3 times, and enhanced the neutrophil migration after 24 h CvL injection (75.8%, p<0.001) and no significant effect was observed in the presence of fMLP. Finally, pre-treatment of mice with dexamethasone (cytokine antagonist) decreased (65.6%, p<0.001), diclofenac (non-selective NSAID) decreased (34.5%, p<0.001) and Celecoxib (selective NSAID) had no effect on leukocyte migration after submission at peritonitis stimulated by CvL, respectively. Summarizing, data suggest that CvL shows pro-inflammatory activity, inducing neutrophil migration probably by pathway on resident macrophage activation and on chemotaxis mediated by cytokines.

Linseed (Linun usitatissimum L.) is an important oilseed whose nutritional value can be impaired due to presence of antinutritional factors and low protein digestibility. Protein fractions from raw linseed meal were extracted, isolated and analyzed in vitro and in vivo. Globulins, the major protein fraction of linseed, showed low in vitro susceptibility to trypsin and chymotrypsin, but its in vivo digestibility was 93.2 %. Albumin fraction had high trypsin inhibition activity (5250 Inhibition Units g(-1)) and presented low molecular mass protein bands, similar to known trypsin inhibitors. Raw linseed consumption caused negative effects on rat growth and reduction of intestinal villi. Results indicate that raw linseed meal must not be used as an exclusive source of protein regardless of the major proteins have high digestibility; digestive enzymes inhibitors in raw linseed probably reduces the protein utilization.

Background: The first case of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Rio Grande do Norte, northeast Brazil, was diagnosed on March 12, 2020; thereafter, the pattern of COVID-19 followed the multiple waves as seen elsewhere. The waves were mostly due to the SARS-CoV-2 virus mutations leading to emergence of variants of concern (VoC). The introduction of new VoCs in a population context of prior SARS-CoV-2 infections or after vaccination has been a challenge in understanding the kinetics of the protective immune response against SARS-CoV-2 . The aim of this study was to investigate the outbreak of SARS-CoV-2 reinfections observed in mid-January 2022 in Rio Grande do Norte state, Brazil when the omicron variant was introduced. Methodology/Principal findings: From a total of 172,965 individuals with mild to severe respiratory symptoms, 58,097 tested positive for SARS-CoV-2 between March 2020 through mid-February 2022. Of those previously infected, 444 had documented a second SARS-CoV-2 infection and 9 of these reinfection cases were selected for sequencing. Genomic analysis revealed that virus lineages diverged between primary and the reinfection, with the latter caused by the Omicron (BA.1) variant among individuals fully vaccinated against SARS-CoV-2. Conclusions/Significance: Once all subjects whose samples were sequenced had prior SARS-CoV-2 infection and were also fully vaccinated, our data suggest that the Omicron variant evades natural and vaccine-induced immunities, confirming the continuous need to decrease transmission and to develop effective blocking vaccines.