J Med Virol
December 2024
Dengue is the most prevalent arboviral disease globally, with Brazil currently experiencing a significant rise in cases. Dengue virus (DENV) typically co-circulates with other clinically and antigenically similar flaviviruses, such as Zika virus (ZIKV). The clinical diagnosis is difficult and accurate serological analysis represents an unmet challenge.
View Article and Find Full Text PDFSci Total Environ
December 2024
BMC Geriatr
October 2024
Background: Although important information concerning COVID-19 vaccination is available, the effects of the CoronaVac and ChadOx-1 vaccines on immunity and the redox balance in the upper airway mucosa of the aged population are not fully understood. Therefore, the aim of this study was to investigate the impacts of two doses of the CoronaVac or ChadOx-1 vaccine on immune/inflammatory responses and oxidative stress in the airway mucosa of older adults.
Methods: Seventy-six older adults of both sexes, with a mean age of 75.
Rev Inst Med Trop Sao Paulo
July 2024
Hepatic injuries in COVID-19 are not yet fully understood and indirect pathways (without viral replication in the liver) have been associated with the activation of vascular mechanisms of liver injury in humans infected with SARS-CoV-2. Golden Syrian hamsters are an effective model for experimental reproduction of moderate and self-limiting lung disease during SARS-CoV-2 infection. As observed in humans, this experimental model reproduces lesions of bronchointerstitial pneumonia and pulmonary vascular lesions, including endotheliitis (attachment of lymphoid cells to the luminal surface of endothelium).
View Article and Find Full Text PDFSeaweed polysaccharides, particularly sulfated ones, exhibited potent antiviral activity against a wide variety of enveloped viruses, such as herpes simplex virus and respiratory viruses. Different mechanisms of action were suggested, which may range from preventing infection to intracellular antiviral activity, at different stages of the viral cycle. Herein, we generated two chemically engineered sulfated fucans (C303 and C304) from Cystoseira indica by an amalgamated extraction-sulfation procedure using chlorosulfonic acid-pyridine/N,N-dimethylformamide and sulfur trioxide-pyridine/N,N-dimethylformamide reagents, respectively.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Basis Dis
June 2024
Zika virus (ZIKV) infection was first associated with Central Nervous System (CNS) infections in Brazil in 2015, correlated with an increased number of newborns with microcephaly, which ended up characterizing the Congenital Zika Syndrome (CZS). Here, we investigated the impact of ZIKV infection on the functionality of iPSC-derived astrocytes. Besides, we extrapolated our findings to a Brazilian cohort of 136 CZS children and validated our results using a mouse model.
View Article and Find Full Text PDFVaccines (Basel)
January 2024
The recently emerged SARS-CoV-2 Omicron sublineages, including the BA.2-derived XBB.1.
View Article and Find Full Text PDFThe raising of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants led to the use of COVID-19 bivalent vaccines, which include antigens of the wild-type (WT) virus, and of the Omicron strain. In this study, we aimed to evaluate the impact of bivalent vaccination on the neutralizing antibody (NAb) response. We enrolled 93 volunteers who had received three or four doses of monovalent vaccines based on the original virus (n = 61), or a booster shot with the bivalent vaccine (n = 32).
View Article and Find Full Text PDFMicroorganisms
November 2023
Microorganisms
September 2023
SARS-CoV-2 diagnostic tests have become an important tool for pandemic control. Among the alternatives for COVID-19 diagnosis, antigen rapid diagnostic tests (Ag-RDT) are very convenient and widely used. However, as SARS-CoV-2 variants may continuously emerge, the replacement of tests and reagents may be required to maintain the sensitivity of Ag-RDTs.
View Article and Find Full Text PDFIntroduction: Infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces rapid production of IgM, IgA, and IgG antibodies directed to multiple viral antigens that may have impact diverse clinical outcomes.
Methods: We evaluated IgM, IgA, and IgG antibodies directed to the nucleocapsid (NP), IgA and IgG to the Spike protein and to the receptor-binding domain (RBD), and the presence of neutralizing antibodies (nAb), in a cohort of unvaccinated SARS-CoV-2 infected individuals, in the first 30 days of post-symptom onset (PSO) (T1).
Results: This study included 193 coronavirus disease 2019 (COVID-19) participants classified as mild, moderate, severe, critical, and fatal and 27 uninfected controls.
Sci Rep
October 2023
Amongst the potential contribution of protein or peptide-display systems to study epitopes with relevant immunological features, the RAD display system stands out as a highly stable scaffold protein that allows the presentation of constrained target peptides. Here, we employed the RAD display system to present peptides derived from the SARS-CoV-2 Spike (S) protein as a tool to detect specific serum antibodies and to generate polyclonal antibodies capable of inhibiting SARS-CoV-2 infectivity in vitro. 44 linear S-derived peptides were genetically fused with the RAD scaffold (RAD-SCoV-epitopes) and screened for antigenicity with sera collected from COVID-19-infected patients.
View Article and Find Full Text PDFJ Immunol Methods
November 2023
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is an enveloped, plus-stranded RNA virus responsible for the Coronavirus Disease 2019 (COVID-19). Patients infected with COVID-19 may be asymptomatic or have symptoms ranging from mild manifestations to severe cases of the disease that could lead to death. The SARS-CoV-2 genome encodes 4 structural proteins, including the Spike protein (S), the Nucleocapsid protein (N), Membrane protein (M) and, the Envelope protein (E).
View Article and Find Full Text PDFSince December 2019, the world has been experiencing the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and we now face the emergence of several variants. We aimed to assess the differences between the wild-type (Wt) (Wuhan) strain and the P.1 (Gamma) and Delta variants using infected K18-hACE2 mice.
View Article and Find Full Text PDFSci Total Environ
July 2023
The COVID-19 pandemic has caused unprecedented negative impacts in the modern era, including economic, social, and public health losses. On the other hand, the potential effects that the input of SARS-CoV-2 in the aquatic environment from sewage may represent on non-target organisms are not well known. In addition, it is not yet known whether the association of SARS-CoV-2 with other pollutants, such as microplastics (MPs), may further impact the aquatic biota.
View Article and Find Full Text PDFSci Total Environ
July 2023
While the multifaceted social, economic, and public health impacts associated with the COVID-19 pandemic are known, little is known about its effects on non-target aquatic ecosystems and organisms. Thus, we aimed to evaluate the potential ecotoxicity of SARS-CoV-2 lysate protein (SARS.CoV2/SP02.
View Article and Find Full Text PDFZika virus (ZIKV), a mosquito-borne pathogen, is an emerging arbovirus associated with sporadic symptomatic cases of great medical concern, particularly among pregnant women and newborns affected with neurological disorders. Serological diagnosis of ZIKV infection is still an unmet challenge due to the co-circulation of the dengue virus, which shares extensive sequence conservation of structural proteins leading to the generation of cross-reactive antibodies. In this study, we aimed to obtain tools for the development of improved serological tests for the detection of ZIKV infection.
View Article and Find Full Text PDFThe present case study describes the dermatological manifestations of COVID-19 in a patient with genetic thrombophilia (MTHFR-C677T mutation) and the identification of a SARS-CoV-2 variant of interest (VOI). A female patient, 47 years old, unvaccinated, with thrombophilia, was diagnosed with COVID-19. She presented with urticarial and maculopapular eruptions from the seventh day of symptoms, which progressed to multiple lesions with dark centers (D-dimer value > 1450 ng/mL).
View Article and Find Full Text PDFBackground: In 2019, the world witnessed the onset of an unprecedented pandemic. By February 2022, the infection by SARS-CoV-2 has already been responsible for the death of more than 5 million people worldwide. Recently, we and other groups discovered that SARS-CoV-2 infection induces ER stress and activation of the unfolded protein response (UPR) pathway.
View Article and Find Full Text PDFVaccines (Basel)
February 2023
Background: Here, we investigated the impact of IFN-lambda-3 polymorphism on specific IgG responses for COVID-19 in older adults seropositive for CMV.
Methods: Blood samples of 25 older adults of both sexes were obtained at three different times: during a micro-outbreak (MO) of SARS-CoV-2 in 2020; eight months after (CURE); and 30 days after the administration of the second dose of ChadOx-1 vaccine (VAC). The specific IgG for both SARS-CoV-2 and CMV antigens, neutralizing antibodies against SARS-CoV-2, and also the polymorphism profile for IFN-lambda-3 (rs12979860 C > T) were assessed.
Int J Environ Res Public Health
January 2023
Background: In this study, we aimed to investigate the specific-antibody response to the COVID-19 vaccination and the immunophenotyping of T cells in older adults who were engaged or not in an exercise training program before the pandemic.
Methods: Ninety-three aged individuals (aged between 60 and 85 years) were separated into 3 groups: practitioners of physical exercise vaccinated with CoronaVac (PE-Co, = 46), or vaccinated with ChadOx-1 (PE-Ch, = 23), and non-practitioners vaccinated with ChadOx-1 (NPE-Ch, = 24). Blood samples were collected before (pre) and 30 days after vaccination with the second vaccine dose.