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51 result(s) for "Olsen, Cara H"
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Durability of Antibody Response and Frequency of SARS-CoV-2 Infection 6 Months after COVID-19 Vaccination in Healthcare Workers
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies decay but persist 6 months postvaccination; lower levels of neutralizing titers persist against Delta than wild-type virus. Of 227 vaccinated healthcare workers tested, only 2 experienced outpatient symptomatic breakthrough infections, despite 59/227 exhibiting serologic evidence of SARS-CoV-2 infection, defined as presence of nucleocapsid protein antibodies.
Both diet and Helicobacter pylori infection contribute to atherosclerosis in pre- and postmenopausal cynomolgus monkeys
A number of viruses and bacterial species have been implicated as contributors to atherosclerosis, potentially providing novel pathways for prevention. Epidemiological studies examining the association between Helicobacter pylori and cardiovascular disease have yielded variable results and no studies have been conducted in nonhuman primates. In this investigation, we examined the relationship between H. pylori infection and atherosclerosis development in socially housed, pre- and postmenopausal cynomolgus macaques consuming human-like diets. Ninety-four premenopausal cynomolgus monkeys (Macaca fascicularis) were fed for 36 months an atherogenic diet deriving its protein from either casein lactalbumin(CL) or high isoflavone soy (SOY). Animals were then ovariectomized and fed either the same or the alternate diet for an additional 36 months. Iliac artery biopsies were obtained at the time of ovariectomy and iliac and coronary artery sections were examined at the end of the study. Evidence of H. pylori infection was found in 64% of the monkeys and 46% of animals had live H. pylori within coronary atheromas as determined by mRNA-specific in situ hybridization. There was a significant linear relationship between the densities of gastric and atheroma organisms. Helicobactor pylori infection correlated with increased intimal plaque area and thickness at both the premenopausal and postmenopausal time points and regardless of diet (p< 0.01), although animals consuming the SOY diet throughout had the least amount of atherosclerosis. Additionally, plasma lipid profiles, intimal collagen accumulation, ICAM-1, and plaque macrophage densities were adversely affected by H. pylori infection among animals consuming the CL diet, while the SOY diet had the opposite effect. Plaque measurements were more highly associated with the densities of cagA-positive H. pylori within coronary atheromas than with the densities of gastric organisms, whereas plasma lipid changes were associated with H. pylori infection, but not cagA status. This study provides strong evidence that live H. pylori infects atheromas, exacerbates atherosclerotic plaque development, and alters plasma lipid profiles independently of diet or hormonal status. Finally, socially subordinate animals relative to their dominant counterparts had a greater prevalence of H. pylori, suggesting a stress effect. The results indicate that early H. pylori eradication could prevent or delay development of cardiovascular disease.
Effects of captopril against radiation injuries in the Göttingen minipig model of hematopoietic-acute radiation syndrome
Our laboratory has demonstrated that captopril, an angiotensin converting enzyme inhibitor, mitigates hematopoietic injury following total body irradiation in mice. Improved survival in mice is correlated with improved recovery of mature blood cells and bone marrow, reduction of radiation-induced inflammation, and suppression of radiation coagulopathy. Here we investigated the effects of captopril treatment against radiation injuries in the Göttingen mini pig model of Hematopoietic-Acute Radiation Syndrome (H-ARS). Minipigs were given captopril orally (0.96 mg/kg) twice daily for 12 days following total body irradiation ( 60 Co 1.79 Gy, 0.42–0.48 Gy/min). Blood was drawn over a time course following irradiation, and tissue samples were collected at euthanasia (32–35 days post-irradiation). We observed improved survival with captopril treatment, with survival rates of 62.5% in vehicle treated and 87.5% in captopril treated group. Additionally, captopril significantly improved recovery of peripheral blood mononuclear cells, and a trend toward improvement in recovery of red blood cells and platelets. Captopril significantly reduced radiation-induced expression of cytokines erythropoietin and granulocyte-macrophage colony-stimulating factor and suppressed radiation-induced acute-phase inflammatory response cytokine serum amyloid protein A. Using quantitative-RT-PCR to monitor bone marrow recovery, we observed significant suppression of radiation-induced expression of redox stress genes and improved hematopoietic cytokine expression. Our findings suggest that captopril activities in the Göttingen minipig model of hematopoietic-acute radiation syndrome reflect findings in the murine model.
The Effects of Berry Extracts on Oxidative Stress in Cultured Cardiomyocytes and Microglial Cells: A Potential Cardioprotective and Neuroprotective Mechanism
Oxidative stress is a key underlying factor in cognitive decline and atherosclerosis. Oxidative stress occurs at the cellular level with an imbalance between reactive oxygen species and reactive nitrogen species and a deficiency in antioxidants. Mounting evidence suggests that berry flavonoids may promote cellular health by exerting antioxidant properties. Black currant and various berry extracts were tested in microglia (BV-2) and cardiomyocyte (HL-1) cell lines to study their biological effects. The principal ingredients in black currant and cranberry extract–delphinidin 3-rutinoside (D3R) and cyanidin 3-glucoside (C3G), were also assessed. A menadione-induced oxidative stressor was used, and its output was quantified to detect oxidative stress (CellROXTM). Black currant extract had similar antioxidant effects as N-acetylcysteine (NAC) in HL-1 cells with regard to cellular protection, whereas cranberry extract was ineffective. In contrast, cranberry extract was comparable in effectiveness to black currant extract in BV-2 cells. D3R and C3G also reduced oxidative stress similarly to whole berry extracts, which indicates that these ingredients may confer the antioxidant effects of berries. Black currant and cranberry extracts inhibit oxidative stress in microglial and cardiomyocyte cell lines. Black currant extract was more effective in reducing oxidative stress in the HL-1 cells, whereas cranberry extract was comparable in reducing oxidative stress in the BV-2 cells. The results suggest that berry flavonoids exert neuro- and cardioprotective effects.
Adverse Effects and Antibody Titers in Response to the BNT162b2 mRNA COVID-19 Vaccine in a Prospective Study of Healthcare Workers
Abstract Background The relationship between postvaccination symptoms and strength of antibody responses is unclear. The goal of this study was to determine whether adverse effects caused by vaccination with the Pfizer/BioNTech BNT162b2 vaccine are associated with the magnitude of vaccine-induced antibody levels. Methods We conducted a single-center, observational cohort study consisting of generally healthy adult participants that were not severely immunocompromised, had no history of coronavirus disease 2019, and were seronegative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein before vaccination. Severity of vaccine-associated symptoms was obtained through participant-completed questionnaires. Testing for immunoglobulin G antibodies against SARS-CoV-2 spike protein and receptor-binding domain was conducted using microsphere-based multiplex immunoassays performed on serum samples collected at monthly visits. Neutralizing antibody titers were determined by microneutralization assays. Results Two hundred six participants were evaluated (69.4% female, median age 41.5 years old). We found no correlation between vaccine-associated symptom severity scores and vaccine-induced antibody titers 1 month after vaccination. We also observed that (1) postvaccination symptoms were inversely correlated with age and weight and more common in women, (2) systemic symptoms were more frequent after the second vaccination, (3) high symptom scores after first vaccination were predictive of high symptom scores after second vaccination, and (4) older age was associated with lower titers. Conclusions Lack of postvaccination symptoms after receipt of the BNT162b2 vaccine does not equate to lack of vaccine-induced antibodies 1 month after vaccination. We found no correlation between BNT162b2-associated symptom severity and vaccine-induced antibody titers 1 month after vaccination. Adverse effects inversely correlated with age and weight, whereas symptom severity after first vaccination was predictive of that after second vaccination.
Prospective Assessment of SARS-CoV-2 Seroconversion (PASS) study: an observational cohort study of SARS-CoV-2 infection and vaccination in healthcare workers
Background SARS-CoV-2 is a recently emerged pandemic coronavirus (CoV) capable of causing severe respiratory illness. However, a significant number of infected people present as asymptomatic or pauci-symptomatic. In this prospective assessment of at-risk healthcare workers (HCWs) we seek to determine whether pre-existing antibody or T cell responses to previous seasonal human coronavirus (HCoV) infections affect immunological or clinical responses to SARS-CoV-2 infection or vaccination. Methods A cohort of 300 healthcare workers, confirmed negative for SARS-CoV-2 exposure upon study entry, will be followed for up to 1 year with monthly serology analysis of IgM and IgG antibodies against the spike proteins of SARS-CoV-2 and the four major seasonal human coronavirus - HCoV-OC43, HCoV-HKU1, HCoV-229E, and HCoV-NL63. Participants will complete monthly questionnaires that ask about Coronavirus Disease 2019 (COVID-19) exposure risks, and a standardized, validated symptom questionnaire (scoring viral respiratory disease symptoms, intensity and severity) at least twice monthly and any day when any symptoms manifest. SARS-CoV-2 PCR testing will be performed any time participants develop symptoms consistent with COVID-19. For those individuals that seroconvert and/or test positive by SARS-CoV-2 PCR, or receive the SARS-CoV-2 vaccine, additional studies of T cell activation and cytokine production in response to SARS-CoV-2 peptide pools and analysis of Natural Killer cell numbers and function will be conducted on that participant’s cryopreserved baseline peripheral blood mononuclear cells (PBMCs). Following the first year of this study we will further analyze those participants having tested positive for COVID-19, and/or having received an authorized/licensed SARS-CoV-2 vaccine, quarterly (year 2) and semi-annually (years 3 and 4) to investigate immune response longevity. Discussion This study will determine the frequency of asymptomatic and pauci-symptomatic SARS-CoV-2 infection in a cohort of at-risk healthcare workers. Baseline and longitudinal assays will determine the frequency and magnitude of anti-spike glycoprotein antibodies to the seasonal HCoV-OC43, HCoV-HKU1, HCoV-229E, and HCoV-NL63, and may inform whether pre-existing antibodies to these human coronaviruses are associated with altered COVID-19 disease course. Finally, this study will evaluate whether pre-existing immune responses to seasonal HCoVs affect the magnitude and duration of antibody and T cell responses to SARS-CoV-2 vaccination, adjusting for demographic covariates.
The effect of geographic origin and destination on congenital heart disease outcomes: a retrospective cohort study
Background Congenital heart disease (CHD) is a common and significant birth defect, frequently requiring surgical intervention. For beneficiaries of the Department of Defense, a new diagnosis of CHD may occur while living at rural duty stations. Choice of tertiary care center becomes a function of geography, referring provider recommendations, and patient preference. Methods Using billing data from the Military Health System over a 5-year period, outcomes for beneficiaries age < 10 years undergoing CHD surgery were compared by patient origin (rural versus urban residence) and the distance to treatment (patient’s home and the treating tertiary care center). These beneficiaries include children of active duty, activated reserves, and federally activated National Guard service members. Analysis of the outcomes were adjusted for procedure complexity risk. Treatment centers were further stratified by annual case volume and whether they publicly reported results in the society of thoracic surgery (STS) outcomes database. Results While increasing distance was associated with the cost of admission, there was no associated risk of inpatient mortality, one year mortality, or increased length of stay. Likewise, rural origination was not significantly associated with target outcomes. Patients traveled farther for STS-reporting centers (STS-pr), particularly high-volume centers. Such high-volume centers (> 50 high complexity cases annually) demonstrated decreased one year mortality, but increased cost and length of stay. Conclusions Together, these findings contribute to the national conversation of rural community medicine versus regionalized subspecialty care; separation of patients between rural areas and more urban locations for initial CHD surgical care does not increase their mortality risk. In fact, traveling to high volume centers may have an associated mortality benefit.
Characteristics and framework analysis of Department of Defense hospital Antibiotic Stewardship Programs guided by the Centers for Disease Control and Prevention Core Elements
Characterization and assessment of Department of Defense's (DoD's) Antibiotic Stewardship Programs (ASPs) to determine adherence to Centers for Disease Control and Prevention (CDC) Core Elements and compare to national adherence. Retrospective, observational with supplemental survey. Facility characteristics and CDC Core Elements (CE) adherence data for 2017-2021 were retrieved from the National Healthcare Safety Network's (NHSN) annual hospital survey with DoD data from the Defense Health Agency and national data from the Antibiotic Resistance and Patient Safety Portal. An online supplemental survey was administered to DoD hospitals. Descriptive statistics and bivariate analyses were completed for facility characteristics and supplemental survey questions to determine correlations between variables. A framework analysis compared DoD ASPs to CEs and Priority Elements. Supplemental surveys were completed for 85.1% of DoD's hospitals. DoD's hospitals were smaller on average than national hospitals. ASP leaders were assigned more often than volunteer and typically served in the role for less than four years. Staffing mix differed, with more equivalent proportions of civilian/contractor to military at larger hospitals in the U.S. Most DoD ASPs consisted of ≤ 25% pharmacists. ASP leaders were largely available on a daily basis; pharmacist leaders spent more time on ASP activities than physicians. CE adherence was high, but in 2021 DoD lagged national adherence in the structural CEs of Leadership, Accountability, and Pharmacy Expertise. DoD hospitals lagged in national adherence to the structural CEs, presenting opportunities for ASP improvement. Refinement of CE adherence measurements, coupled with impact on health outcomes, could aid in better-identifying areas for improvement.
Estimating the decay of protective antibodies induced by SARS-CoV-2 mRNA vaccination and hybrid immunity
Starting in 2020, we quantified anti-wildtype SARS-CoV-2 spike sera IgG at monthly intervals from generally healthy adults after various doses of mRNA-based COVID-19 vaccination and in the context of hybrid immunity. Confirmed post-vaccination infections and subclinical infections identified by longitudinal serology were removed from vaccine-only analyses. Over 400 days, the two-dose vaccine-alone antibody response decayed at a half-life ( t 1/2 ) of 59.8 days compared with a t 1/2 of 99.7 days after receipt of one booster dose. In the hybrid immunity model, the t 1/2 was greater at 241 days. Using cut-offs for correlation of protection obtained in a prior study, we modeled that individuals with hybrid immunity maintain antibody levels above a 75% correlate of immunity for 283 days after an immune-boosting event. These data offer insights into SARS-CoV-2 antibody decay kinetics that may inform COVID-19 vaccine timing in the younger (age under 60), healthy adult population.
Comparative Probiotic Strain Efficacy in the Prevention of Eczema in Infants and Children: A Systematic Review and Meta-Analysis
Eczema affects 3.5% of the global population, with peak prevalence during infancy. Eczema has no cure, but probiotics have been suggested as a preventative measure. To comprehensively analyze the impact of prenatal and postnatal probiotic supplementation on the prevention of infantile and childhood eczema. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and PubMed were searched for randomized controlled trials regarding probiotic usage and eczema development from 1945 to 2013. Participants included were 7 years old or younger with probiotic exposure in utero or below 6 months of age and who was not diagnosed previously. 27 publications describing 16 studies assessing 10 probiotics in 2,797 participants met our criterion. The pooled relative risk of all the studies, 0.74 (95% confidence interval 0.67, 0.82), indicated that probiotic supplementation in the first several years of life did have a significant impact on development of eczema. During evaluation of the studies, heterogeneity of terms and definitions for similar primary and secondary outcomes were identified. The use of probiotic supplements during pregnancy and/or during infancy creates a statistically significant decline in the incidence of eczema. The heterogeneity of terms and definitions regarding eczema is the major limitation of these studies.