Publications by authors named "Deanna Zhu"

Few studies have described changes in SARS-CoV-2 antibody levels in response to infection and vaccination at frequent intervals and over extended follow-up periods. The purpose of this study was to assess changes in SARS-CoV-2-specific antibody responses among a prospective cohort of health care personnel over 18 months with up to 22 samples per person. Antibody levels and live virus neutralization were measured before and after mRNA-based vaccination with results stratified by (1) SARS-CoV-2 infection status prior to initial vaccination and (2) SARS-CoV-2 infection at any point during follow-up.

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Background: Infection precautions (IP) facilitate standardized and safe patient care. Research has demonstrated several barriers to IP adherence among health care personnel (HCP) but potential exposure risk to SARS-CoV-2 and job role has not been considered.

Methods: Researchers used self-reported baseline surveys with 191 HCPs at a university medical center to examine factors that may have affected IP adherence (eg, personal protective equipment [PPE] and hand hygiene errors) over the 2 weeks prior to the survey.

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The envelope (E) glycoprotein is the primary target of type-specific (TS) neutralizing antibodies (nAbs) after infection with any of the four distinct dengue virus serotypes (DENV1-4). nAbs can be elicited to distinct structural E domains (EDs) I, II, or III. However, the relative contribution of these domain-specific antibodies is unclear.

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The four dengue virus (DENV) serotypes infect several hundred million people each year. Although primary infection is generally mild, subsequent infection by differing serotypes increases the risk for symptomatic disease ranging from fever to life-threatening shock. Despite the availability of licensed vaccines, a comprehensive understanding of antibodies that target the viral envelope protein and protect from infection remains incomplete.

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A hallmark of dengue virus (DENV) pathogenesis is the potential for antibody-dependent enhancement, which is associated with deadly DENV secondary infection, complicates the identification of correlates of protection, and negatively impacts the safety and efficacy of DENV vaccines. Antibody-dependent enhancement is linked to antibodies targeting the fusion loop (FL) motif of the envelope protein, which is completely conserved in mosquito-borne flaviviruses and required for viral entry and fusion. In the current study, we utilized saturation mutagenesis and directed evolution to engineer a functional variant with a mutated FL (D2-FL), which is not neutralized by FL-targeting monoclonal antibodies.

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A hallmark of Dengue virus (DENV) pathogenesis is the potential for antibody-dependent enhancement, which is associated with deadly DENV secondary infection, complicates the identification of correlates of protection, and negatively impacts the safety and efficacy of DENV vaccines. ADE is linked to antibodies targeting the fusion loop (FL) motif of the envelope protein, which is completely conserved in mosquito-borne flaviviruses and required for viral entry and fusion. In the current study, we utilized saturation mutagenesis and directed evolution to engineer a functional variant with a mutated FL (D2-FL) which is not neutralized by FL-targeting monoclonal antibodies.

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The four dengue virus serotypes co-circulate globally and cause significant human disease. Dengue vaccine development is challenging because some virus-specific antibodies are protective, while others are implicated in enhanced viral replication and more severe disease. Current dengue tetravalent vaccines contain four live attenuated serotypes formulated to theoretically induce balanced protective immunity.

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Background: Health care personnel (HCP) are at high risk for exposure to the SARS-CoV-2 virus. While personal protective equipment (PPE) may mitigate this risk, prospective data collection on its use and other risk factors for seroconversion in this population is needed.

Objective: The primary objectives of this study are to (1) determine the incidence of, and risk factors for, SARS-CoV-2 infection among HCP at a tertiary care medical center and (2) actively monitor PPE use, interactions between study participants via electronic sensors, secondary cases in households, and participant mental health and well-being.

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Article Synopsis
  • Diagnosing toxoplasmic encephalitis (TE) is difficult due to limited testing options, especially in low-resource settings, leading many clinicians to rely on empirical treatments.
  • A novel urine diagnostic method using specially dyed nanoparticles significantly enhances the detection of T. gondii antigens, achieving a detection limit of 7.8pg/ml for GRA1 and 31.3pg/ml for SAG1.
  • The study suggests that the new test shows good specificity for TE, particularly with GRA1, and indicates potential for noninvasive diagnosis using nanoparticle technology.
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The effect of SARS-CoV-2 infection on response to mRNA-based SARS-CoV-2 vaccines is not well-described. We assessed longitudinal SARS-CoV-2-specific antibody responses pre- and post-vaccination among individuals with and without prior infection. The antibody response to the first vaccine dose was almost two-fold higher in individuals who were seropositive before vaccination compared to those who were seronegative, suggesting that prior infection primes the immune response to the first dose of mRNA-based vaccine.

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The rational design of dengue virus (DENV) vaccines requires a detailed understanding of the molecular basis for antibody-mediated immunity. The durably protective antibody response to DENV after primary infection is serotype specific. However, there is an incomplete understanding of the antigenic determinants for DENV type-specific (TS) antibodies, especially for DENV serotype 3, which has only one well-studied, strongly neutralizing human monoclonal antibody (mAb).

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Objective: Prior posttraumatic stress disorder (PTSD) and elevated threat perceptions predict posttraumatic psychopathology after evaluation for acute coronary syndrome (ACS), but most research has measured threat retrospectively. We investigated how threat perceptions during ACS evaluation in the emergency department (ED) and upon recall were associated with posttraumatic psychopathology burden due to prior trauma and the suspected ACS.

Methods: Perceived threat was assessed in the ED, and ED threat recall was assessed upon inpatient transfer/discharge, along with acute stress disorder (ASD) symptoms due to suspected ACS and PTSD symptoms due to prior trauma.

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Background: Large numbers of international children with cleft lip-cleft palate are adopted in the United States; many underwent their first operation before arrival.

Methods: The authors reviewed records of internationally adopted children with cleft lip-cleft palate treated by one surgeon over 25 years. This study focused on anatomical types, frequency/methods of repair, correction of unrepaired deformities, and secondary procedures in this country.

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