In a previous study, the Schistosoma mansoni Rho1 protein was able to complement Rho1 null mutant Saccharomyces cerevisiae cells at restrictive temperatures and under osmotic stress (low calcium ...concentration) better than the human homologue (RhoA). It is known that under osmotic stress, the S. cerevisiae Rho1 triggers two distinct pathways: activation of the membrane 1,3-beta-glucan synthase enzymatic complex and activation of the protein kinase C1 signal transduction pathway, promoting the transcription of response genes. In the present work the SmRho1 protein and its mutants smrho1E97P, smrho1L101T, and smrho1E97P, L101T were used to try to clarify the basis for the differential complementation of Rho1 knockout yeast strain by the human and S. mansoni genes. Experiments of functional complementation in the presence of caffeine and in the presence of the osmotic regulator sorbitol were conducted. SmRho1 and its mutants showed a differential complementation of the yeast cells in the presence of caffeine, since smrho1E97P and smrho1E97P, L101T mutants showed a delay in the growth when compared to the yeast complemented with the wild type SmRho1. However, in the presence of sorbitol and caffeine the wild type SmRho1 and mutants showed a similar complementation phenotype, as they allowed yeast growth in all caffeine concentrations tested.
The SARS-CoV-2 pandemic has had a social and economic impact worldwide, and vaccination is an efficient strategy for diminishing those damages. New adjuvant formulations are required for the high ...vaccine demands, especially adjuvant formulations that induce a Th1 phenotype. Herein we assess a vaccination strategy using a combination of Alum and polyinosinic:polycytidylic acid Poly(I:C) adjuvants plus the SARS-CoV-2 spike protein in a prefusion trimeric conformation by an intradermal (ID) route. We found high levels of IgG anti-spike antibodies in the serum by enzyme linked immunosorbent assay (ELISA) and high neutralizing titers against SARS-CoV-2
in vitro
by neutralization assay, after two or three immunizations. By evaluating the production of IgG subtypes, as expected, we found that formulations containing Poly(I:C) induced IgG2a whereas Alum did not. The combination of these two adjuvants induced high levels of both IgG1 and IgG2a. In addition, cellular immune responses of CD4
+
and CD8
+
T cells producing interferon-gamma were equivalent, demonstrating that the Alum + Poly(I:C) combination supported a Th1 profile. Based on the high neutralizing titers, we evaluated B cells in the germinal centers, which are specific for receptor-binding domain (RBD) and spike, and observed that more positive B cells were induced upon the Alum + Poly(I:C) combination. Moreover, these B cells produced antibodies against both RBD and non-RBD sites. We also studied the impact of this vaccination preparation spike protein with Alum + Poly(I:C) in the lungs of mice challenged with inactivated SARS-CoV-2 virus. We found a production of IgG, but not IgA, and a reduction in neutrophil recruitment in the bronchoalveolar lavage fluid (BALF) of mice, suggesting that our immunization scheme reduced lung inflammation. Altogether, our data suggest that Alum and Poly(I:C) together is a possible adjuvant combination for vaccines against SARS-CoV-2 by the intradermal route.
Highlights • Gastroenteritis is one of the most important causes of morbidity and mortality in children. • Noroviruses are a leading cause of sporadic cases and outbreaks of acute gastroenteritis. • ...Norovirus annual detection rates increased over the study period. • The detection of norovirus was higher among young children.
Despite the intramuscular route being the most used vaccination strategy against SARS-CoV-2, the intradermal route has been studied around the globe as a strong candidate for immunization against ...SARS-CoV-2. Adjuvants have shown to be essential vaccine components that are capable of driving robust immune responses and increasing the vaccination efficacy. In this work, our group aimed to develop a vaccination strategy for SARS-CoV-2 using a trimeric spike protein, by testing the best route with formulations containing the adjuvants AddaS03, CpG, MPL, Alum, or a combination of two of them. Our results showed that formulations that were made with AddaS03 or CpG alone or AddaS03 combined with CpG were able to induce high levels of IgG, IgG1, and IgG2a; high titers of neutralizing antibodies against SARS-CoV-2 original strain; and also induced high hypersensitivity during the challenge with Spike protein and a high level of IFN-γ producing CD4+ T-cells in mice. Altogether, those data indicate that AddaS03, CpG, or both combined may be used as adjuvants in vaccines for COVID-19.
Investigation of major viruses responsible for acute viral gastroenteritis, such as norovirus (NoV), rotavirus species A (RVA) and human adenovirus (HAdV), was conducted in the mountainous region of ...the state of Rio de Janeiro in a lettuce-producing area. Irrigation water and lettuce samples were collected at different production stages. Viruses were concentrated using an adsorption-elution method and detected by quantitative polymerase chain reaction (qPCR). We detected HAdV in all collection points, although no virus infectivity was shown. The RVA was the most prevalent virus from both water (16.7% 10/60) and lettuce samples (11.1% 4/36), with loads ranging from 2.97 × 102 to 6.88 × 103 genomic copies per litre (gc L-1) and 6.24 × 102 to 1.30 × 104 gc per 25 g, respectively. NoV was detected in 8.33% 8/96 in water and lettuce samples, with concentrations ranging from 7.29 × 101 to 1.92 × 103 gc L-1 and from 4.29 × 101 to 2.98 × 103 gc 25 g-1, respectively. Escherichia coli values also demonstrated poor quality of the irrigation and washing water. The presence of at least two different virus strains in all sites reveals the need to improve basic sanitation measures in order to increase food safety.
ABSTRACT
Background and Objective:
Norovirus (NoV) infections are known to have high‐morbidity and mortality rates and are a major health problem globally. The impact of NoV on child development is, ...however, poorly understood. We evaluated the distribution of NoV genotypes in children from a low‐income Brazilian semiarid region, in relation with their clinical symptoms, nutritional status, and co‐pathogens.
Methods:
The test population included children aged 2 to 36 months from 6 cities of the Brazilian semiarid region. Fecal samples were collected from each child, along with the information regarding their socioeconomic/clinical conditions using a standardized questionnaire. Detection and quantification of NoV were performed by reverse‐transcription quantitative polymerase chain reaction, followed by molecular and phylogenetic analyses.
Results:
The NoV detection rate was 45.2%. Presence of NoV was associated with lower z scores for weight‐for‐age (P = 0.03), weight‐for‐height (P = 0.03), and body mass index‐for‐age (P = 0.03). NoV infection was associated with more frequent respiratory illnesses (P < 0.01). GII.P7 (polymerase) and GII.3 (capsid) were the most frequent NoV genotypes. Analysis of the open reading frame (ORF)1‐2 junction identified recombinant NoV strains in 80% of the sequenced samples. Enteroaggregative Escherichia coli coinfection was the major predictor for diarrhea in NoV‐positive samples (P < 0.02). Moreover, Shigella spp was also associated with NoV‐positive diagnosis (P = 0.02).
Conclusions:
This study highlights the genetic variability of NoV and, associated co‐infections and undernutrition in infants from low‐income Brazilian semiarid region.
ABSTRACT
Background:
Rotavirus A (RVA) is one of the leading causes of acute gastroenteritis worldwide; however, few studies assessed RVA genetics with community surveillance.
Objectives:
This study ...aimed to investigate clinical data, genetic diversity, and coinfection patterns of RVA infections in children from 2 to 36 months old with or without community childhood diarrhea in the Brazilian semiarid region during postvaccination era.
Methods:
We enrolled and collected socioeconomic/clinical information using a standardized questionnaire and fecal samples from 291 children. Viral RNA samples were extracted and analyzed using quantitative reverse transcription polymerase chain reaction to establish the diagnosis of RVA. Sequencing of VP7 and VP4 (VP8*) regions and phylogenetic analysis were performed.
Results:
RVA‐negative diagnosis was associated with children 24 to 36 months old with complete vaccination schedule. Genotype G1P8 was the most prevalent (57%), whereas unusual genotypes including G1P4, G2P8, and G3P9 were also detected. G1‐ and P8‐positive samples showed high degrees of similarity with the vaccine strain. RVA coinfections were frequently observed, and enteroaggregative Escherichia coli was the most prevalent copathogen.
Conclusions:
These results demonstrate that genotype G1P8 is the most prevalent strain. VP7 and/or VP8* gene segments arising from RV1 vaccine strain were documented in these children, suggesting shedding or herd vaccination. Moreover, our study indicates full vaccination is important for protection against RVA infections.
Background
Effective and safe vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical to controlling the COVID-19 pandemic and will remain the most important tool ...in limiting the spread of the virus long after the pandemic is over.
Methods
We bring pioneering contributions on the maintenance of the immune response over a year on a real-life basis study in 1,587 individuals (18-90 yrs, median 39 yrs; 1,208 female/379 male) who underwent vaccination with two doses of CoronaVac and BNT162b2 booster after 6-months of primary protocol.
Findings
Elevated levels of anti-spike IgG antibodies were detected after CoronaVac vaccination, which significantly decreased after 80 days and remained stable until the introduction of the booster dose. Heterologous booster restored antibody titers up to-1·7-fold, changing overall seropositivity to 96%. Titers of neutralising antibodies to the Omicron variant were lower in all timepoints than those against Delta variant. Individuals presenting neutralising antibodies against Omicron also presented the highest titers against Delta and anti-Spike IgG. Cellular immune response measurement pointed out a mixed immune profile with a robust release of chemokines, cytokines, and growth factors on the first month after CoronaVac vaccination followed by a gradual reduction over time and no increase after the booster dose. A stronger interaction between those mediators was noted over time. Prior exposure to the virus leaded to a more robust cellular immune response and a rise in antibody levels 60 days post CoronaVac than in individuals with no previous COVID-19. Both vaccines were safe and well tolerated among individuals.
Interpretation
Our data approach the effectiveness of CoronaVac association with BNT162b2 from the clinical and biological perspectives, aspects that have important implications for informing decisions about vaccine boosters.
Funding
Fiocruz, Brazil.
This work addresses the unrelated parallel machine scheduling problem with sequence‐dependent setup times, in which a set of jobs must be scheduled for execution by one of the several available ...machines. Each job has a machine‐dependent processing time. Furthermore, given multiple jobs, there are additional setup times, which vary based on the sequence and machine employed. The objective is to minimize the schedule's completion time (makespan). The problem is NP‐hard and of significant practical relevance. The present paper investigates the performance of four different stochastic local search (SLS) methods designed for solving the particular scheduling problem: simulated annealing, iterated local search, late acceptance hill‐climbing, and step counting hill‐climbing. The analysis focuses on design questions, tuning effort, and optimization performance. Simple neighborhood structures are considered. All proposed SLS methods performed significantly better than two state‐of‐the‐art hybrid heuristics, especially for larger instances. Updated best‐known solutions were generated for 901 of the 1000 large benchmark instances considered, demonstrating that particular SLS methods are simple yet powerful alternatives to current approaches for addressing the problem. Implementations of the contributed algorithms have been made available to the research community.
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