Publications by authors named "Michael Bierdeman"

Virus-neutralizing antibodies are often accepted as a correlate of protection against infection, though questions remain about which components of the immune response protect against SARS-CoV-2 infection. In this small observational study, we longitudinally measured spike receptor binding domain (RBD)-specific and nucleocapsid (NP)-specific serum IgG in a human cohort immunized with the Pfizer BNT162b2 vaccine. NP is not encoded in the vaccine, so an NP-specific response is serological evidence of natural infection.

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The emergence of Alpha, Beta, Gamma, Delta, and Omicron variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for several million deaths up to now. Because of the huge amount of vaccine escape mutations in the spike (S) protein for different variants, the design of material for combating SARS-CoV-2 is very important for our society. Herein, we report on the design of a human angiotensin converting enzyme 2 (ACE2) peptide-conjugated plasmonic-magnetic heterostructure, which has the capability for magnetic separation, identification via surface enhanced Raman spectroscopy (SERS), and inhibition of different variant SARS-CoV-2 infections.

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Obesity is a significant factor for increased morbidity and mortality upon infection with SARS-CoV-2. Because of the higher potential for negative outcomes following infection of individuals with obesity, the impact of body mass index (BMI) on vaccine immunogenicity and efficacy is an important public health concern. Few studies have measured the magnitude and durability of the vaccine-specific response in relation to BMI.

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With the increased prevalence of new SARS-CoV-2 variants of concern, such as Delta and Omicron, the COVID-19 pandemic has become an ongoing human health disaster, killing millions worldwide. SARS-CoV-2 invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition, heparan sulfate (HS) on the surface of host cells plays an important role as a co-receptor for this viral pathogen-host cell interaction.

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The COVID-19 pandemic is a major human health concern. The pathogen responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition to ACE2, heparan sulfate (HS) on the surface of host cells also plays a significant role as a co-receptor.

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Several enveloped viruses, including herpesviruses attach to host cells by initially interacting with cell surface heparan sulfate (HS) proteoglycans followed by specific coreceptor engagement which culminates in virus-host membrane fusion and virus entry. Interfering with HS-herpesvirus interactions has long been known to result in significant reduction in virus infectivity indicating that HS play important roles in initiating virus entry. In this study, we provide a series of evidence to prove that specific sulfations as well as the degree of polymerization (dp) of HS govern human cytomegalovirus (CMV) binding and infection.

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Purpose: is an ocular pathogen and a leading cause of keratitis. It produces hemolysins and at least 3 proteases. The purpose of the present study is to compare the secretion of hemolysins and proteases between 28 ocular isolates and one non-ocular strain and to determine their relationship to ocular virulence in selected strains using a rabbit model of infection.

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is a leading cause of bacterial keratitis, especially in users of contact lenses. These infections are characterized by extensive degradation of the corneal tissue mediated by protease activities, including both protease IV (PIV) and the small protease (PASP). The virulence role of PIV was determined by the reduced virulence of a PIV-deficient mutant relative to its parent strain and the mutant after genetic complementation (rescue).

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is a major cause of corneal infections that can cause reduced vision, even blindness. Secreted toxins cause tissue damage and inflammation resulting in scars that lead to vision loss. Identifying tissue damaging proteins is a prerequisite to limiting these harmful reactions.

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Purpose: Pseudomonas aeruginosa is the leading cause of contact lens-associated bacterial keratitis. Secreted bacterial proteases have a key role in keratitis, including the P. aeruginosa small protease (PASP), a proven corneal virulence factor.

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Pneumonia is a pulmonary disease affecting people of all ages and is consistently a leading cause of childhood mortality and adult hospitalizations. and are major lung pathogens commonly associated with community-acquired and nosocomial pneumonia. Additionally, mixed lung infections involving these bacterial pathogens are increasing in prevalence and are frequently more severe than single infections.

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Purpose: This study analyzed the toxicity of purified gamma-toxin from Staphylococcus aureus and the protectiveness of antisera to gamma-toxin in the rabbit cornea.

Materials And Methods: Gamma-toxin was purified from cultures of alpha-toxin deficient S. aureus strain Newman Δhla.

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Background: Saline nasal irrigations (SNI) are an important adjunct in the treatment of rhinosinusitis, and many patients prepare and store these solutions in their homes without an awareness of the potential for contamination. The objectives of this study were to determine if such contamination occurs and the effect of preparation methods on contamination.

Methods: Stock solutions of various tonicities and pHs were prepared using boiled, bottled, and distilled water (n = 57).

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Purpose: Staphylococcus aureus infection of the anterior chamber can occur after cataract surgery, causing inflammation and extensive damage to the iris. Alpha-toxin, the most potent S. aureus corneal toxin, was tested as a possible mediator of damage to the iris, and alpha-toxin anti-serum and a chemical toxin inhibitor were tested as potential pathology-reducing agents.

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Purpose: To investigate the effectiveness of a high-affinity human monoclonal antibody Fab fragment to Staphylococcus aureus alpha-toxin (LTM14 Fab) as therapy for S. aureus keratitis.

Methods: A single topical drop of the LTM14 Fab antibody to alpha-toxin alone, or in 0.

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