Antiviral Potential and Chemical Composition of Wild Spreng. Populations (Asteraceae) from Córdoba, Argentina: Perspective on Population Variability.

Medicinal plants have been explored worldwide as potential alternatives for the prevention and treatment of different diseases, including viral infections. Spreng. (Asteraceae) is a native medicinal species widely used in South America.

High-dimensional analysis of 16 SARS-CoV-2 vaccine combinations reveals lymphocyte signatures correlating with immunogenicity.

The range of vaccines developed against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) provides a unique opportunity to study immunization across different platforms. In a single-center cohort, we analyzed the humoral and cellular immune compartments following five coronavirus disease 2019 (COVID-19) vaccines spanning three technologies (adenoviral, mRNA and inactivated virus) administered in 16 combinations. For adenoviral and inactivated-virus vaccines, heterologous combinations were generally more immunogenic compared to homologous regimens.

Cuprous oxide nanoparticles incorporated into a polymeric matrix embedded in fabrics to prevent spread of SARS-CoV-2.

This paper describes the development of a coating for cotton and polypropylene (PP) fabrics based on a polymeric matrix embedded with cuprous oxide nanoparticles (CuO@SDS NPs) in order to inactivate SARS-CoV-2 and manufactured by a simple process using a dip-assisted layer-by-layer technology, at low curing temperature and without the need for expensive equipment, capable of achieving disinfection rates of up to 99%. The polymeric bilayer coating makes the surface of the fabrics hydrophilic, enabling the transportation of the virus-infected droplets to achieve the rapid inactivation of SARS-CoV-2 by contact with the CuO@SDS NPs incorporated in the coated fabrics.

Receptor-binding domain-based SARS-CoV-2 vaccine adjuvanted with cyclic di-adenosine monophosphate enhances humoral and cellular immunity in mice.

Novel adjuvants are highly desired to improve immune responses of SARS-CoV-2 vaccines. This work reports the potential of the stimulator of interferon genes (STING) agonist adjuvant, the cyclic di-adenosine monophosphate (c-di-AMP), in a SARS-CoV-2 vaccine based on the receptor binding domain (RBD). Here, mice immunized with two doses of monomeric RBD adjuvanted with c-di-AMP intramuscularly were found to exhibit stronger immune responses compared to mice vaccinated with RBD adjuvanted with aluminum hydroxide (Al(OH) ) or without adjuvant.

Safety and effectiveness of RBD-specific polyclonal equine F(ab´)2 fragments for the treatment of hospitalized patients with severe Covid-19 disease: A retrospective cohort study.

Background: Passive immunotherapy has been evaluated as a therapeutic alternative for patients with COVID-19 disease. Equine polyclonal immunotherapy for COVID-19 (EPIC) showed adequate safety and potential efficacy in a clinical trial setting and obtained emergency use authorization in Argentina. We studied its utility in a real world setting with a larger population.

New insights into the antiviral activity of nordihydroguaiaretic acid: Inhibition of dengue virus serotype 1 replication.

Background: Dengue virus (DENV) is considered one of the most important pathogens in the world causing 390 million infections each year. Currently, the development of vaccines against DENV presents some shortcomings and there is no antiviral therapy available for its infection. An important challenge is that both treatments and vaccines must be effective against all four DENV serotypes.

The extent of infectious SARS-CoV-2 shedding in an Argentinean cohort.

Background: To analyze the infectious extent of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in different settings where prevention strategies are critical to limit infection spread, we evaluated SARS-COV-2 viability to guide public health policies regarding isolation criteria and infection control.

Methods: We attempted viral isolation in 82 nasopharyngeal swabs from 72 patients with confirmed SARS-COV-2 infection. Study population was divided into four groups: (i) Patients during the first week of symptoms; (ii) Patients with prolonged positive PCR; (iii) Healthcare workers from a hospital participating of an outbreak investigation, with SARS-COV-2 infection confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) and (iv) Recipients of convalescent immune plasma (CIP).

Inactivation of Herpes Simplex Virus by Photosensitizing Anthraquinones Isolated from Heterophyllaea pustulata.

is a phototoxic plant from Argentina. Aerial parts extracts, high in photosensitizing anthraquinones, have shown antiviral activity. The purpose of this study was to study the antiherpetic activity of the main purified anthraquinones, even evaluating their competence as photodynamic sensitizers to photo-stimulate the antiviral effect.

First report of antiviral activity of nordihydroguaiaretic acid against Fort Sherman virus (Orthobunyavirus).

The genus Orthobunyavirus are a group of viruses within arbovirus, with a zoonotic cycle, some of which could lead to human infection. A characteristic of these viruses is their lack of antiviral treatment or vaccine for its prevention. The objective of this work was to study the in vitro antiviral activity of nordihydroguaiaretic acid (NDGA), the most important active compound of Larrea divaricata Cav.

Autochthonous circulation of Saint Louis encephalitis and West Nile viruses in the Province of La Rioja, Argentina.

St. Louis encephalitis (SLEV) and West Nile (WNV) arboviruses, which circulate in Argentina, are maintained in enzootic transmission cycles involving Culex mosquitoes (vectors) and birds belonging to orders Passeriformes and Columbiformes (amplifier hosts). The objective of this work was to determine the circulation of both viruses among wild birds in a semiarid ecosystem in the Province of La Rioja through a serologic survey.

Genomic characterization of orthobunyavirus of veterinary importance in America.

During 2013, in Argentina, three new isolates of serogroup Bunyamwera virus (genus Orthobunyavirus, family Peribunyaviridae) were recovered from two horses with encephalitis, and from an aborted equine fetus. In the present study, we report the complete genome sequence, genetic characterization, and phylogenetic analysis of three new strains isolated in Argentina to clarifying their relationship within the Bunyamwera serogroup virus and to investigate the evolutionary history of viruses with segmented genomes.

Neuronal Degeneration in Mice Induced by an Epidemic Strain of Saint Louis Encephalitis Virus Isolated in Argentina.

Saint Louis encephalitis virus (SLEV) is a neglected flavivirus that causes severe neurological disorders. The epidemic strain of SLEV, CbaAr-4005, isolated during an outbreak in Córdoba city (Argentina), causes meningitis and encephalitis associated with neurological symptoms in a murine experimental model. Here, we identified the affected brain areas and the damage triggered by this neurotropic arbovirus.

Alphaviruses: Serological Evidence of Human Infection in Paraguay (2012-2013).

Introduction: Alphaviruses can produce febrile illness and encephalitis in dead-end hosts such as horses and humans. Within this genus, the Venezuelan Equine Encephalitis virus (VEEV) complex includes pathogenic epizootic subtypes and enzootic subtypes that are not pathogenic in horses (except subtype IE, Mexican strains), although they can cause febrile symptoms in humans. The Rio Negro virus (RNV-VEEV subtype VI) circulates in Argentina, where it was associated with undifferentiated febrile illness.

Parietin: an efficient photo-screening pigment in vivo with good photosensitizing and photodynamic antibacterial effects in vitro.

The photophysical, photoinduced pro-oxidant and antibacterial properties in vitro of the natural occurring parietin (PTN; 1,8-dihydroxy-3-methoxy-6-methyl-9,10-anthraquinone) were evaluated. PTN was extracted from the lichen identified as Teloschistes flavicans (Sw.) Norm.

Activity Patterns of St. Louis Encephalitis and West Nile Viruses in Free Ranging Birds during a Human Encephalitis Outbreak in Argentina.

St. Louis encephalitis virus (SLEV) (Flavivirus) is a reemerging arbovirus in the southern cone of South America. In 2005, an outbreak of SLEV in central Argentina resulted in 47 human cases with 9 deaths.

[Serological evidence of St. Louis encephalitis virus circulation in birds from Buenos Aires City, Argentina].

Our goal was to determine the presence of neutralizing antibodies against St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) in sera of wild and domestic birds from Buenos Aires City, Argentina. From October 2012 to April 2013, 180 samples were collected and processed by the microneutralization technique.

Venezuelan equine encephalitis viruses (VEEV) in Argentina: serological evidence of human infection.

Venezuelan equine encephalitis viruses (VEEV) are responsible for human diseases in the Americas, producing severe or mild illness with symptoms indistinguishable from dengue and other arboviral diseases. For this reason, many cases remain without certain diagnosis. Seroprevalence studies for VEEV subtypes IAB, ID, IF (Mosso das Pedras virus; MDPV), IV (Pixuna virus; PIXV) and VI (Rio Negro virus; RNV) were conducted in persons from Northern provinces of Argentina: Salta, Chaco and Corrientes, using plaque reduction neutralization test (PRNT).

Larvicidal activity of crude extracts from Larrea cuneifolia (Zygophyllaceae) and of its metabolite nordihydroguaiaretic acid against the vector Culex quinquefasciatus (Diptera: Culicidae).

Introduction: The aim of the present study was to analyze the larvicidal activity of different crude extracts of Larrea cuneifolia and its most abundant lignan, nordihydroguaiaretic acid (NDGA), against Culex quinquefasciatus.

Methods: Chloroform, methanol, and aqueous extracts from L. cuneifolia and NDGA were tested against larvae of Cx.

In vitro antiviral activity of Heterophyllaea pustulata extracts.

The antiviral activity was tested of different polarity extracts, with differing chemical composition, obtained from aerial parts of Heterophyllaea pustulata Hook f. (Rubiaceae) against Herpes Simplex Virus Type I (HSV-1) and Saint Louis Encephalitis Virus (SLEV). The Vero cell line was employed as a host cell for the antiviral assessment of benzene (Ben), ethyl acetate (EtOAc) and ethanol (EtOH) extracts by means of the Neutral Red uptake assay and plaque reduction test.

West Nile virus in birds, Argentina.

West Nile Virus in Birds, Argentina

Genotype III Saint Louis encephalitis virus outbreak, Argentina, 2005.

Twenty-six years after it was last detected, Saint Louis encephalitis virus (SLEV) genotype III reemerged in 2005 in C6rdoba, Argentina, where it caused an outbreak. Two genotype III SLEV strains were isolated from Culex quinquefasciatus. A 71.