Front Cell Infect Microbiol
April 2024
Res Sq
February 2024
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.
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.
Front Immunol
June 2022
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.
medRxiv
March 2022
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.
View Article and Find Full Text PDFBackground: 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.
In this study, we accessed culturable fungal assemblages present in the sediments of three lakes potentially impacted anthropogenically in the Fildes Peninsula, King George Island, Antarctica and identified 63 taxa. Cladosporium sp. 2, Pseudeurotium hygrophilum, and Pseudogymnoascus verrucosus were recovered from the sampled sediments of all lakes.
View Article and Find Full Text PDFWe recovered 195 fungal isolates from the sediments of different lakes in the Antarctic Peninsula, which were screened to detect bioactive compounds. Forty-two taxa belonging to the phyla Ascomycota, Basidiomycota, and Mortierellomycota were identified. Thelebolus globosus, Antarctomyces psychrotrophicus, Pseudogymnoascus verrucosus, Vishniacozyma victoriae, and Phenoliferia sp.
View Article and Find Full Text PDFParasitology
June 2020
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.
View Article and Find Full Text PDFVaccine
February 2020
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.
View Article and Find Full Text PDFVaccines (Basel)
December 2019
The yellow fever (YF) vaccine consists of an attenuated virus, and despite its relative safety, some adverse events following YF vaccination have been described. At the end of 2016, Brazil experienced the most massive sylvatic yellow fever outbreak over the last 70 years and an intense campaign of YF vaccination occurred in Minas Gerais state in Southeast Brazil from 2016 to 2018. The present study aimed to develop a genotyping tool and investigate 21 cases of suspected adverse events following YF vaccination.
View Article and Find Full Text PDFWe accessed the culturable mycobiota present in marine sediments at different depths in Antarctica Ocean. Acremonium fusidioides, Penicillium allii-sativi, Penicillium chrysogenum, Penicillium palitans, Penicillium solitum, and Pseudogymnoascus verrucosus were identified. Penicillium allii-sativi was the dominant species.
View Article and Find Full Text PDFEquine 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.
View Article and Find Full Text PDFInt Immunopharmacol
July 2018
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.
View Article and Find Full Text PDFMolecular biology techniques were used to identify 218 fungi from soil samples collected from four islands of Antarctica. These consisted of 22 taxa of 15 different genera belonging to the Zygomycota, Ascomycota, and Basidiomycota. Mortierella, Antarctomyces, Pseudogymnoascus, and Penicillium were the most frequently isolated genera and Penicillium tardochrysogenum, Penicillium verrucosus, Goffeauzyma gilvescens, and Mortierella sp.
View Article and Find Full Text PDFDengue is currently regarded as a major public health problem worldwide. In a hyperendemic region during an outbreak, we detected the co-circulation of all Dengue virus (DENV) serotypes including two different genotypes of DENV-3 and DENV-4, and concurrent infections with up to three serotypes were identified in symptomatic patients. A total of 49 acute phase plasma samples from patients clinically suspected of dengue were collected during the 4 weeks of May 2013.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFMem Inst Oswaldo Cruz
August 2015
Drug resistance is a global threat and one of the main contributing factors to tuberculosis (TB) outbreaks. The goal of this study was to analyse the molecular profile of multidrug-resistant TB (MDR-TB) in the state of Santa Catarina in southern Brazil. Fifty-three MDR Mycobacterium tuberculosis clinical isolates were analysed by spoligotyping and a partial region of the rpoB gene, which is associated with rifampicin resistance (RMP-R), was sequenced.
View Article and Find Full Text PDFRAP1 (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).
View Article and Find Full Text PDFWe surveyed the diversity and capability of producing bioactive compounds from a cultivable fungal community isolated from oligotrophic soil of continental Antarctica. A total of 115 fungal isolates were obtained and identified in 11 taxa of Aspergillus, Debaryomyces, Cladosporium, Pseudogymnoascus, Penicillium and Hypocreales. The fungal community showed low diversity and richness, and high dominance indices.
View Article and Find Full Text PDFPLoS One
February 2016
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.
View Article and Find Full Text PDFMem Inst Oswaldo Cruz
June 2014
The identification of mycobacteria is essential because tuberculosis (TB) and mycobacteriosis are clinically indistinguishable and require different therapeutic regimens. The traditional phenotypic method is time consuming and may last up to 60 days. Indeed, rapid, affordable, specific and easy-to-perform identification methods are needed.
View Article and Find Full Text PDFVirol J
August 2013
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.
View Article and Find Full Text PDFJ Virol Methods
January 2013
Dengue virus (DENV) is the most prevalent arbovirus in the world, found mainly in tropical regions. As clinical manifestations present frequently as nonspecific febrile illness, laboratory diagnosis is essential to confirm DENV infections and for epidemiological studies. Recombinant envelope (E) antigens of four serotypes of DENV were used to develop an immunoglobulin G enzyme-linked immunosorbent assay (IgG-ELISA).
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