Publications by authors named "Charles L Bailey"

A striking feature of COVID-19 disease is the broad spectrum of risk factors associated with case severity, as well as the diversity of clinical manifestations. While no central agent has been able to explain the pathogenesis of SARS-CoV-2 infection, the factors that most robustly correlate with severity are risk factors linked to aging. Low serum levels of Klotho, an anti-aging protein, strongly correlate with the pathogenesis of the same risk factors and manifestations of conditions similar to those expressed in severe COVID-19 cases.

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Article Synopsis
  • * Researchers found that inhibiting p70 S6K with rapamycin effectively prevented Rift Valley fever virus (RVFV) pathogenesis in mice, while other inhibitors had limited effects on viral replication when used alone.
  • * The combination of different kinase inhibitors, particularly using PF-4708671 with BI-D1870, showed a strong potential to significantly reduce RVFV replication, suggesting a promising approach for treatment strategies against this virus.
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As the Ebola outbreak in West Africa wanes, it is time for the international scientific community to reflect on how to improve the detection of and coordinated response to future epidemics. Our interdisciplinary team identified key lessons learned from the Ebola outbreak that can be clustered into three areas: environmental conditions related to early warning systems, host characteristics related to public health, and agent issues that can be addressed through the laboratory sciences. In particular, we need to increase zoonotic surveillance activities, implement more effective ecological health interventions, expand prediction modeling, support medical and public health systems in order to improve local and international responses to epidemics, improve risk communication, better understand the role of social media in outbreak awareness and response, produce better diagnostic tools, create better therapeutic medications, and design better vaccines.

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Bacillus anthracis is a dangerous pathogen of humans and many animal species. Its virulence has been mainly attributed to the production of Lethal and Edema toxins as well as the antiphagocytic capsule. Recent data indicate that the nitric oxide (NO) synthase (baNOS) plays an important pathogenic role at the early stage of disease by protecting bacteria from the host reactive species and S-nytrosylating the mitochondrial proteins in macrophages.

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Pneumonic tularemia is caused by inhalation of Francisella tularensis, one of the most infectious microbes known. We wanted to study the kinetics of the initial and early interactions between bacterium and host cells in the lung. To do this, we examined the infection of A549 airway epithelial cells with the live vaccine strain (LVS) of F.

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Bacillus anthracis, a causative agent of anthrax, is able to germinate and survive within macrophages. A recent study suggested that B. anthracis-derived nitric oxide (bNO) is a key aspect of bacterial defense that protects bacterial DNA from oxidative burst in the macrophages.

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To achieve widespread dissemination in the host, Bacillus anthracis cells regulate their attachment to host endothelium during infection. Previous studies identified BslA (Bacillus anthracis S-layer Protein A), a virulence factor of B. anthracis, as necessary and sufficient for adhesion of vegetative cells to human endothelial cells.

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Background: Endemic/Enzootic maintenance mechanisms like vertical transmission (pathogen passage from infected adults to their offspring) are central in the epidemiology of zoonotic pathogens. In Kenya, Rift Valley fever virus (RVFV) may be maintained by vertical transmission in ground-pool mosquitoes such as . RVFV can cause serious morbidity and mortality in humans and livestock.

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The causative agent of anthrax, Bacillus anthracis, is capable of circumventing the humoral and innate immune defense of the host and modulating the blood chemistry in circulation to initiate a productive infection. It has been shown that the pathogen employs a number of strategies against immune cells using secreted pathogenic factors such as toxins. However, interference of B.

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Inhalational anthrax is caused by spores of the bacterium Bacillus anthracis (B. anthracis), and is an extremely dangerous disease that can kill unvaccinated victims within 2 weeks. Modern antibiotic-based therapy can increase the survival rate to ∼50%, but only if administered presymptomatically (within 24-48 h of exposure).

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Anthrax is a zoonotic disease caused by Bacillus anthracis. The infection is associated with inflammation and sepsis, but little is known about the acute-phase response during disease and the nature of the bacterial factors causing it. In this study, we examined the levels of the acute-phase proteins (APPs) in comparative experiments using mice challenged with spores and a purified B.

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Bacillus anthracis infection is associated with severe hemostatic disturbances but their roles and contribution to fatality remain incompletely characterized. We undertook analyses of circulating antithrombin levels during the course of infection using a comparison of lethal and nonlethal murine anthrax models. Plasma samples were obtained from DBA/2 mice challenged intraperitoneally with the spores of either toxigenic B.

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Outbreaks of Rift Valley fever (RVF) in Egypt, Yemen, and Saudi Arabia have indicated the potential for this disease to spread from its enzootic areas in sub-Saharan Africa. Because little is known about the potential for most African mosquito species to transmit RVF virus (family Bunyaviridae, genus Phlebovirus, RVFV), we conducted studies to determine the vector competence of selected African species of mosquitoes for this virus. All eight species tested [Aedes palpalis (Newstead), Aedes mcintoshi Huang, Aedes circumluteolus (Theobald), Aedes calceatus Edwards, Aedes aegypti (L.

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Pathology data from the anthrax animal models show evidence of significant increases in vascular permeability coincident with hemostatic imbalances manifested by thrombocytopenia, transient leucopenia, and aggressive disseminated intravascular coagulation. In this study we hypothesized that anthrax infection modulates the activity of von Willebrand factor (VWF) and its endogenous regulator ADAMTS13, which play important roles in hemostasis and thrombosis, including interaction of endothelial cells with platelets. We previously demonstrated that purified anthrax neutral metalloproteases Npr599 and InhA are capable of cleaving a variety of host structural and regulatory proteins.

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To reduce the assay time for detecting virus-specific antibodies in serum, we developed microarray-based active immunoassay techniques for detecting West Nile virus (WNV)-specific IgM molecules in chicken blood. The assay uses electrophoretic concentration of IgM molecules onto WNV antigens arrayed on a dialysis membrane followed by detection of bound IgM molecules with functionalized magnetic beads as active labels. This assay takes only 15 minutes and has the same sensitivity as a commercially available human WNV IgM antibody-capture enzyme-linked immunosorbent assay (commonly called a MAC-ELISA) modified for use with chicken sera.

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The authors developed a monitoring and risk mapping system using normalized difference vegetation index (NDVI) times series data derived from the advanced very high resolution radiometer (AVHRR) instrument on polar orbiting national oceanographic and atmospheric administration (NOAA) satellites to map areas with a potential for a Rift Valley fever (RVF) outbreaks in sub-Saharan Africa. This system is potentially an important tool for local, national and international organisations involved in the prevention and control of animal and human disease, permitting focused and timely implementation of disease control strategies several months before an outbreak. We are currently developing a geographic information system (GIS)-based remotely sensed early warning system for potential RVF vectors in the United States.

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Anthrax toxin can induce hemolysis in the presence of polymorphonuclear cells (PMNs), an activity primarily mediated by protective antigen, with synergic effects provided by lethal factor and edema factor. Lethal factor and edema factor, individually or in combination, are incapable of lysing red blood cells. The requirement for the presence of PMNs indicates that hemolysis associated with Bacillus anthracis infection is indirect rather than direct, as observed in many other bacterial infections.

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