Publications by authors named "Deanna Larson"

Animal models that are susceptible to SARS-CoV-2 infection and develop clinical signs like human COVID-19 are desired to understand viral pathogenesis and develop effective medical countermeasures. The golden Syrian hamster is important for the study of SARS-CoV-2 since hamsters are naturally susceptible to SARS-CoV-2. However, infected hamsters show only limited clinical disease and resolve infection quickly.

View Article and Find Full Text PDF

Pandemic SARS-CoV-2 has undergone rapid evolution resulting in the emergence of many variants with mutations in the spike protein, some of which appear to evade antibody neutralization, transmit more efficiently, and/or exhibit altered virulence. This raises significant concerns regarding the efficacy of anti-S monoclonal antibody-based therapeutics which have failed against variant SARS-CoV-2 viruses. To address this concern, SAB-185, a human anti-SARS-CoV-2 polyclonal antibody was generated in the DiversitAb platform.

View Article and Find Full Text PDF

The prevalence of the Omicron subvariant BA.2.75 rapidly increased in India and Nepal during the summer of 2022, and spread globally.

View Article and Find Full Text PDF

The BA.2 sublineage of the SARS-CoV-2 Omicron variant has become dominant in most countries around the world; however, the prevalence of BA.4 and BA.

View Article and Find Full Text PDF
Article Synopsis
  • The emergence of the Omicron variant BA.2 has heightened worries about the reduced effectiveness of current COVID-19 vaccines and treatments due to its mutations, with BA.2 now dominant in many countries.
  • Research comparing the infectivity and pathogenicity of BA.2 to BA.1 in mice and hamsters found that both variants exhibit similar levels of infectivity but are less pathogenic than earlier SARS-CoV-2 strains.
  • Despite a significant decrease in neutralizing antibody response from COVID-19 survivors and vaccine recipients against BA.2, some therapeutic monoclonal antibodies and antiviral drugs still show effectiveness in treating BA.2 infections in hamsters.
View Article and Find Full Text PDF

The recent emergence of SARS-CoV-2 Omicron variants possessing large numbers of mutations has raised concerns of decreased effectiveness of current vaccines, therapeutic monoclonal antibodies, and antiviral drugs for COVID-19 against these variants1,2. While the original Omicron lineage, BA.1, has become dominant in many countries, BA.

View Article and Find Full Text PDF

The rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created a global health emergency. While most human disease is mild to moderate, some infections lead to a severe disease characterized by acute respiratory distress, hypoxia, anosmia, ageusia, and, in some instances, neurological involvement. Small-animal models reproducing severe disease, including neurological sequela, are needed to characterize the pathophysiological mechanism(s) of disease and to identify medical countermeasures.

View Article and Find Full Text PDF
Article Synopsis
  • The Omicron variant B.1.1.529 has raised concerns about its ability to evade vaccine protection and therapeutic antibodies.
  • Research using mice and hamsters revealed that B.1.1.529 caused less severe respiratory infections compared to previous SARS-CoV-2 variants, even though it binds strongly to mouse ACE2.
  • The findings indicate a milder disease response in rodents infected with B.1.1.529, which aligns with some early clinical observations in humans.
View Article and Find Full Text PDF

Despite the development and deployment of antibody and vaccine countermeasures, rapidly-spreading SARS-CoV-2 variants with mutations at key antigenic sites in the spike protein jeopardize their efficacy. The recent emergence of B.1.

View Article and Find Full Text PDF

Purpose: Telemedical applications have only recently begun to coalesce into the field of telemedicine due to varying definitions of telemedicine and issues around reimbursement. This process has been accelerated by the COVID-19 pandemic and the ensuing expansion of telemedicine delivery. This article demonstrates the development of a set of proposed competencies for a telemedicine curriculum in graduate medical education.

View Article and Find Full Text PDF

Pandemic SARS CoV-2 has been undergoing rapid evolution during spread throughout the world resulting in the emergence of many Spike protein variants, some of which appear to either evade antibody neutralization, transmit more efficiently, or potentially exhibit increased virulence. This raises significant concerns regarding the long-term efficacy of protection elicited after primary infection and/or from vaccines derived from single virus Spike (S) genotypes, as well as the efficacy of anti-S monoclonal antibody based therapeutics. Here, we used fully human polyclonal human IgG (SAB-185), derived from hyperimmunization of transchromosomic bovines with DNA plasmids encoding the SARS-CoV-2 Wa-1 strain S protein or purified ectodomain of S protein, to examine the neutralizing capacity of SAB-185 and the protective efficacy of passive SAB-185 antibody (Ab) transfer .

View Article and Find Full Text PDF

Background: Trimethylamine--oxide (TMAO), a choline-derived gut microbiota-dependent metabolite, is a newly recognized risk marker for cardiovascular disease. We sought to determine: (1) TMAO response to meals containing free versus lipid-soluble choline and (2) effects of gut microbiome on TMAO response.

Methods: In a randomized, controlled, double-blinded, crossover study, healthy men ( = 37) were provided meals containing 600 mg choline either as choline bitartrate or phosphatidylcholine, or no choline control.

View Article and Find Full Text PDF

In this study, we determined the impact of the total Western diet (TWD) for rodents and its macro- and micronutrient components on weight gain and biomarkers of metabolic function in mice compared to a 45% fat diet-induced obesity (DIO) diet and the standard AIN93G diet. We hypothesized that mice fed the TWD would have increased body fat with indicators of metabolic syndrome similar to mice consuming the DIO diet. As expected, DIO-fed mice acquired a metabolic syndrome phenotype typified by increased energy intake, increased body weight gain, increased fat mass, higher fasting glucose, impaired glucose tolerance, and higher plasma leptin relative to the AIN93G diet.

View Article and Find Full Text PDF

Background: Tacaribe virus (TCRV) is a less biohazardous relative of the highly pathogenic clade B New World arenaviruses that cause viral hemorrhagic fever syndromes and require handling in maximum containment facilities not readily available to most researchers. AG129 type I and II interferon receptor knockout mice have been shown to be susceptible to TCRV infection, but the pathogenic mechanisms contributing to the lethal disease are unclear.

Methods: To gain insights into the pathogenesis of TCRV infection in AG129 mice, we assessed hematologic and cytokine responses during the course of infection, as well as changes in the permeability of the vascular endothelium.

View Article and Find Full Text PDF
Article Synopsis
  • Imiquimod is a topical medication that enhances the immune response, and this study examines its effectiveness against vaccinia virus infections in immunosuppressed mice.
  • Mice treated with imiquimod (1% cream) showed longer survival times and smaller lesions compared to control groups, indicating its potential antiviral properties.
  • The study also found that delaying treatment after infection still yielded positive effects, but increasing the imiquimod concentration reduced its effectiveness.
View Article and Find Full Text PDF

Background: A growing number of arenaviruses can cause a devastating viral hemorrhagic fever (VHF) syndrome. They pose a public health threat as emerging viruses and because of their potential use as bioterror agents. All of the highly pathogenic New World arenaviruses (NWA) phylogenetically segregate into clade B and require maximum biosafety containment facilities for their study.

View Article and Find Full Text PDF

Background: A number of RNA viruses cause viral hemorrhagic fever (VHF), in which proinflammatory mediators released from infected cells induce increased permeability of the endothelial lining of blood vessels, leading to loss of plasma volume, hypotension, multi-organ failure, shock and death. The optimal treatment of VHF should therefore include both the use of antiviral drugs to inhibit viral replication and measures to prevent or correct changes in vascular function. Although rodent models have been used to evaluate treatments for increased vascular permeability (VP) in bacterial sepsis, such studies have not been performed for VHF.

View Article and Find Full Text PDF

We evaluated the impact of a 15-hospital, rural, multi-state intensive care unit (ICU) telemedicine program. Acute Physiology, Age, and Chronic Health Evaluation (APACHE III) scores, raw mortality rates, and actual-to-predicted length of stay (LOS) ratios and mortality ratios were used. Surveys evaluated program impact in smaller facilities and satisfaction of the physicians staffing the remote center.

View Article and Find Full Text PDF