Immunogenicity and safety of inactivated SARS-CoV-2 vaccine (CoronaVac) using two-dose primary protocol in children and adolescents (Immunita-002, Brazil): A phase IV six-month follow up.

Introduction: Vaccines are essential for the prevention and control of several diseases, indeed, monitoring the immune response generated by vaccines is crucial. The immune response generated by vaccination against SARS-CoV-2 in children and adolescents is not well defined regarding to the intensity and medium to long-term duration of a protective immune response, which may point out the need of booster doses and might support the decisions in public health.

Objective: The study aims to evaluate the immunogenicity and safety of inactivated SARS-CoV-2 vaccine (CoronaVac) in a two-dose primary protocol in children and adolescent aging from 3 to 17 years old in Brazil.

Booster dose of BNT162b2 after two doses of CoronaVac improves neutralization of SARS-CoV-2 Omicron variant.

Background: The emergence of the new SARS-CoV-2 Omicron variant, which is known to have a large number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination.

Methods: Based on viral microneutralization assays, we evaluated in 90 individuals the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme.

Results: Here we show that the percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 16.

Immunogenicity, Effectiveness, and Safety of Inactivated Virus (CoronaVac) Vaccine in a Two-Dose Primary Protocol and BNT162b2 Heterologous Booster in Brazil (Immunita-001): A One Year Period Follow Up Phase 4 Study.

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.

Booster dose of BNT162b2 in a CoronaVac primary vaccination protocol improves neutralization of SARS-CoV-2 Omicron variant.

The emergence of the new SARS-CoV-2 Omicron variant, which is known to accumulate a huge number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination. In this scenario, we evaluated the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme. The percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 17% and 10%, respectively.

Searching for plant-derived antivirals against dengue virus and Zika virus.

Background: The worldwide epidemics of diseases as dengue and Zika have triggered an intense effort to repurpose drugs and search for novel antivirals to treat patients as no approved drugs for these diseases are currently available. Our aim was to screen plant-derived extracts to identify and isolate compounds with antiviral properties against dengue virus (DENV) and Zika virus (ZIKV).

Methods: Seven thousand plant extracts were screened in vitro for their antiviral properties against DENV-2 and ZIKV by their viral cytopathic effect reduction followed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, previously validated for this purpose.

Free-living amoebae and their relationship to air quality in hospital environments: characterization of spp. obtained from air-conditioning systems.

Free-living amoebae (FLA) are widely dispersed in the environment, can cause opportunistic and non-opportunistic infections in humans and other animals. The aim of the present study was characterize FLA obtained from air-conditioners of a public hospital in the city of Florianópolis, SC, Brazil. Fifty-four dust samples were collected of air conditioners, and were inoculated on 1.

Design and production of dengue virus chimeric proteins useful for developing tetravalent vaccines.

Dengue virus (DENV) is a Flavivirus estimated to cause 390 million infections/year. Currently, there is no anti-viral specific treatment for dengue, and efficient DENV vector control is still unfeasible. Here, we designed and produced chimeric proteins containing potential immunogenic epitopes from the four DENV serotypes in an attempt to further compose safer, balanced tetravalent dengue vaccines.

Equine infectious anemia virus in naturally infected horses from the Brazilian Pantanal.

Equine infectious anemia (EIA) has a worldwide distribution, and is widespread in Brazil. The Brazilian Pantanal presents with high prevalence comprising equine performance and indirectly the livestock industry, since the horses are used for cattle management. Although EIA is routinely diagnosed by the agar gel immunodiffusion test (AGID), this serological assay has some limitations, so PCR-based detection methods have the potential to overcome these limitations and act as complementary tests to those currently used.

HIV aspartyl protease inhibitors modify the percentage of activated leukocytes, as well as serum levels of IL-17A and NO during experimental leishmaniasis.

HIV aspartyl protease inhibitors are able to modulate multiple defense mechanisms. However, their influence on the immune response against Leishmania has rarely been investigated. The aim of our study was to investigate whether in vivo treatment with HIV aspartyl protease inhibitors is able to modulate the immune response during Leishmania infection.

Booster dose after 10 years is recommended following 17DD-YF primary vaccination.

A single vaccination of Yellow Fever vaccines is believed to confer life-long protection. In this study, results of vaccinees who received a single dose of 17DD-YF immunization followed over 10 y challenge this premise. YF-neutralizing antibodies, subsets of memory T and B cells as well as cytokine-producing lymphocytes were evaluated in groups of adults before (NVday0) and after (PVday30-45, PVyear1-4, PVyear5-9, PVyear10-11, PVyear12-13) 17DD-YF primary vaccination.

RAP1 GTPase overexpression is associated with cervical intraepithelial neoplasia.

RAP1 (RAS proximate 1), a small GTP-binding protein of the RAS superfamily, is a putative oncogene that is highly expressed in several malignant cell lines and types of cancers, including some types of squamous cell carcinoma. However, the participation of RAP1 in cervical carcinogenesis is unknown. We conducted a cross-sectional study of paraffin-embedded cervical biopsies to determine the association of RAP1 with cervical intraepithelial neoplasia (CIN).

Dengue virus 2 American-Asian genotype identified during the 2006/2007 outbreak in Piauí, Brazil reveals a Caribbean route of introduction and dissemination of dengue virus in Brazil.

Dengue virus (DENV) is the most widespread arthropod-borne virus, and the number and severity of outbreaks has increased worldwide in recent decades. Dengue is caused by DENV-1, DENV- 2, DENV-3 and DENV-4 which are genetically distant. The species has been subdivided into genotypes based on phylogenetic studies.

Nitric oxide synthase expression correlates with death in an experimental mouse model of dengue with CNS involvement.

Background: The clinical presentation of dengue is classified by the World Health Organization into dengue without warning signs, dengue with warning signs and severe dengue. Reports of neurological disease caused by Dengue virus (DENV) are becoming frequent, with symptoms that include reduced consciousness, severe headache, neck stiffness, focal neurological signs, tense fontanelle and convulsions. However, the immune mechanisms involved in neurovirulence remain poorly understood.

Interferons and scleroderma-a new clue to understanding the pathogenesis of scleroderma?

Scleroderma or systemic sclerosis (SSc) is a complex disease characterized by vasculopathy and deregulated immune and fibroblast activation. The resulting excessive production of collagens and other extracellular matrix proteins by fibroblasts as well as the inflammatory response leads to the development of scleroderma. Recently, some emerging data have been showing a possible link between the type I and II interferons (IFNs) and SSc pathogenesis.

Increased expression of 2'5'oligoadenylate synthetase and double-stranded RNA dependent protein kinase messenger RNAs on affected skin of systemic sclerosis patients.

Scleroderma or systemic sclerosis (SSc) is an autoimmune disorder of unknown aetiology characterized by excessive collagen synthesis and subsequent deposition on the skin and various internal organs. Interferons (IFNs) are well-known immunomodulators and inhibitors of collagen production. However, IFN therapy has been implicated in the development or exacerbation of several autoimmune diseases, including SSc.

Integrin alpha 11 is a novel type I interferon stimulated gene.

Interferons (IFNs) are a family of cytokines that have many biological functions in the cell, including regulation of cellular growth, differentiation, immunomodulation, and viral replication by inducing a set of interferon stimulated genes (ISGs). Based on their structure and biological activities IFNs are subdivided into two groups: type I IFNs, which includes IFN-alpha and IFN-beta and type II IFNs, represented by IFN-gamma. The aim of this work was to investigate whether integrin alpha 11 (ITGA-11), a novel collagen-binding integrin, is responsive to type I IFN treatment.

Protease nexin-1 messenger RNA levels are not affected by serum or interferon beta in cultured systemic sclerosis fibroblasts.

The aim of the present study was to analyze the effect of serum and human recombinant beta interferon (rIFNbeta) treatment on PN-1 mRNA levels in cultured dermal fibroblasts obtained from the skin of healthy donors and from lesional skin of systemic sclerosis (SSc) patients with the limited (CREST syndrome) or the diffuse form of SSc. Total RNA was isolated from fibroblasts derived from the skin of healthy individuals and from lesional skin of patients with CREST syndrome and the diffuse form of SSc cultured under different conditions (1% or 10% serum-supplemented medium) and treated with 500 IU/ml of rIFNbeta. PN-1 gene expression was assessed by Northern blot analysis.