1,715 research outputs found
Applications of high-throughput single B-cell sequencing to accelerate rational vaccine design
Understanding the antibody repertoire response to vaccination is critical for the rational design and evaluation of experimental vaccines. Immune receptors comprise two chains encoded by separate mRNA strands and thus conventional NextGen sequencing fails to identify the native pairings encoded by individual lymphocytes. To overcome this limitation, we are applying recent technical advances in high-throughput sequencing of complete antibodies (i.e., paired heavy and light chain sequencing) to generate a quantitative understanding of experimental vaccine performance and to accelerate vaccine design. We apply repertoire-based metrics of vaccine-elicited antibodies to evaluate and select promising candidate immunogens for inducing HIV-1 Envelope-specific VRC01-class antibodies. The VRC01 class of broadly neutralizing antibodies have been observed in multiple individuals and targets the HIV CD4 binding site via a common recognition motif that requires specific features in both heavy and light chains (e.g., VH1-2 heavy chain V-gene and a short, £5 amino acid light chain CDR3). We are using paired heavy and light chain sequencing to quantify the performance of various candidate HIV immunogens for inducing VRC01-class broadly neutralizing HIV antibodies in transgenic mouse models. We are also elucidating the ontogeny of antibodies in vaccinated and naturally infected human subjects and animal models via interrogation of paired heavy and light chain antibody sequences and antibody synthesis/testing of promising clones, including experimental influenza vaccine trials and a Phase I Ebola vaccine trial. These next-generation immunoanalytic approaches are providing detailed molecular feedback regarding experimental vaccine performance to accelerate vaccine design efforts against pathogens of major public health importance
Characterization of skin sympathetic nerve activity in patients with cardiomyopathy and ventricular arrhythmia
Background
Heightened sympathetic nerve activity is associated with occurrence of ventricular arrhythmia (VA).
Objective
To investigate the association of skin sympathetic nerve activity (SKNA) and VA occurrence.
Methods
We prospectively enrolled 65 patients with severe cardiomyopathy. Of these, 39 had recent sustained VA episodes (VA-1 group), 11 had intractable VA undergoing sedation with general anesthesia (VA-2 group), and 15 had no known history of VA (VA-Ctrl group). All patients had simultaneous SKNA and electrocardiogram recording. SKNA was assessed using an average value (aSKNA), a variable value (vSKNA), and the number of bursts of SKNA (bSKNA).
Results
The VA-1 group had higher aSKNA and vSKNA compared with the VA-Ctrl group (aSKNA: 1.41 ± 0.53 μV vs 0.98 ± 0.41 μV, P = .003; vSKNA: 0.52 ± 0.22 μV vs 0.30 ± 0.16 μV, P 15% reduction in aSKNA after therapy was associated with a lower subsequent VA event rate (hazard ratio, 0.222; 95% CI, 0.057–0.864; P = .03).
Conclusion
Patients with VA had increased SKNA as compared with control. Both SKNA and sustained VA could be suppressed by general anesthesia. The aSKNA at baseline was an independent predictor of VA recurrence
Applying the balanced scorecard to local public health performance measurement: deliberations and decisions
<p>Abstract</p> <p>Background</p> <p>All aspects of the heath care sector are being asked to account for their performance. This poses unique challenges for local public health units with their traditional focus on population health and their emphasis on disease prevention, health promotion and protection. Reliance on measures of health status provides an imprecise and partial picture of the performance of a health unit. In 2004 the provincial Institute for Clinical Evaluative Sciences based in Ontario, Canada introduced a public-health specific balanced scorecard framework. We present the conceptual deliberations and decisions undertaken by a health unit while adopting the framework.</p> <p>Discussion</p> <p>Posing, pondering and answering key questions assisted in applying the framework and developing indicators. Questions such as: Who should be involved in developing performance indicators? What level of performance should be measured? Who is the primary intended audience? Where and how do we begin? What types of indicators should populate the health status and determinants quadrant? What types of indicators should populate the resources and services quadrant? What type of indicators should populate the community engagement quadrant? What types of indicators should populate the integration and responsiveness quadrants? Should we try to link the quadrants? What comparators do we use? How do we move from a baseline report card to a continuous quality improvement management tool?</p> <p>Summary</p> <p>An inclusive, participatory process was chosen for defining and creating indicators to populate the four quadrants. Examples of indicators that populate the four quadrants of the scorecard are presented and key decisions are highlighted that facilitated the process.</p
Tracking Changes in Mobility Before and After the First SARS-CoV-2 Vaccination Using Global Positioning System Data in England and Wales (Virus Watch): Prospective Observational Community Cohort Study.
BACKGROUND: Evidence suggests that individuals may change adherence to public health policies aimed at reducing the contact, transmission, and spread of the SARS-CoV-2 virus after they receive their first SARS-CoV-2 vaccination when they are not fully vaccinated. OBJECTIVE: We aimed to estimate changes in median daily travel distance of our cohort from their registered addresses before and after receiving a SARS-CoV-2 vaccine. METHODS: Participants were recruited into Virus Watch starting in June 2020. Weekly surveys were sent out to participants, and vaccination status was collected from January 2021 onward. Between September 2020 and February 2021, we invited 13,120 adult Virus Watch participants to contribute toward our tracker subcohort, which uses the GPS via a smartphone app to collect data on movement. We used segmented linear regression to estimate the median daily travel distance before and after the first self-reported SARS-CoV-2 vaccine dose. RESULTS: We analyzed the daily travel distance of 249 vaccinated adults. From 157 days prior to vaccination until the day before vaccination, the median daily travel distance was 9.05 (IQR 8.06-10.09) km. From the day of vaccination to 105 days after vaccination, the median daily travel distance was 10.08 (IQR 8.60-12.42) km. From 157 days prior to vaccination until the vaccination date, there was a daily median decrease in mobility of 40.09 m (95% CI -50.08 to -31.10; P<.001). After vaccination, there was a median daily increase in movement of 60.60 m (95% CI 20.90-100; P<.001). Restricting the analysis to the third national lockdown (January 4, 2021, to April 5, 2021), we found a median daily movement increase of 18.30 m (95% CI -19.20 to 55.80; P=.57) in the 30 days prior to vaccination and a median daily movement increase of 9.36 m (95% CI 38.6-149.00; P=.69) in the 30 days after vaccination. CONCLUSIONS: Our study demonstrates the feasibility of collecting high-volume geolocation data as part of research projects and the utility of these data for understanding public health issues. Our various analyses produced results that ranged from no change in movement after vaccination (during the third national lock down) to an increase in movement after vaccination (considering all periods, up to 105 days after vaccination), suggesting that, among Virus Watch participants, any changes in movement distances after vaccination are small. Our findings may be attributable to public health measures in place at the time such as movement restrictions and home working that applied to the Virus Watch cohort participants during the study period
Context-dependent conservation responses to emerging wildlife diseases
Emerging infectious diseases pose an important threat to wildlife. While established protocols exist for combating outbreaks of human and agricultural pathogens, appropriate management actions before, during, and after the invasion of wildlife pathogens have not been developed. We describe stage-specific goals and management actions that minimize disease impacts on wildlife, and the research required to implement them. Before pathogen arrival, reducing the probability of introduction through quarantine and trade restrictions is key because prevention is more cost effective than subsequent responses. On the invasion front, the main goals are limiting pathogen spread and preventing establishment. In locations experiencing an epidemic, management should focus on reducing transmission and disease, and promoting the development of resistance or tolerance. Finally, if pathogen and host populations reach a stable stage, then recovery of host populations in the face of new threats is paramount. Successful management of wildlife disease requires risk-taking, rapid implementation, and an adaptive approach."Funding was provided by the US National Science Foundation (grants EF-0914866, DGE-0741448, DEB-1115069, DEB-1336290) and the National Institutes of Health (grant 1R010AI090159)."https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/14024
Novel Role for the AnxA1-Fpr2/ALX Signaling Axis as a Key Regulator of Platelet Function to Promote Resolution of Inflammation
Background: Ischemia reperfusion injury (I/RI) is a common complication of cardiovascular diseases. Resolution of detrimental I/RI-generated prothrombotic and proinflammatory responses is essential to restore homeostasis. Platelets play a crucial part in the integration of thrombosis and inflammation. Their role as participants in the resolution of thromboinflammation is underappreciated; therefore we used pharmacological and genetic approaches, coupled with murine and clinical samples, to uncover key concepts underlying this role. Methods: Middle cerebral artery occlusion with reperfusion was performed in wild-type or annexin A1 (AnxA1) knockout (AnxA1-/-) mice. Fluorescence intravital microscopy was used to visualize cellular trafficking and to monitor light/dye-induced thrombosis. The mice were treated with vehicle, AnxA1 (3.3 mg/kg), WRW4 (1.8 mg/kg), or all 3, and the effect of AnxA1 was determined in vivo and in vitro. Results: Intravital microscopy revealed heightened platelet adherence and aggregate formation post I/RI, which were further exacerbated in AnxA1-/- mice. AnxA1 administration regulated platelet function directly (eg, via reducing thromboxane B2 and modulating phosphatidylserine expression) to promote cerebral protection post-I/RI and act as an effective preventative strategy for stroke by reducing platelet activation, aggregate formation, and cerebral thrombosis, a prerequisite for ischemic stroke. To translate these findings into a clinical setting, we show that AnxA1 plasma levels are reduced in human and murine stroke and that AnxA1 is able to act on human platelets, suppressing classic thrombin-induced inside-out signaling events (eg, Akt activation, intracellular calcium release, and Ras-associated protein 1 [Rap1] expression) to decrease IIbβ3 activation without altering its surface expression. AnxA1 also selectively modifies cell surface determinants (eg, phosphatidylserine) to promote platelet phagocytosis by neutrophils, thereby driving active resolution. (n=5-13 mice/group or 7-10 humans/group.) Conclusions: AnxA1 affords protection by altering the platelet phenotype in cerebral I/RI from propathogenic to regulatory and reducing the propensity for platelets to aggregate and cause thrombosis by affecting integrin (IIbβ3) activation, a previously unknown phenomenon. Thus, our data reveal a novel multifaceted role for AnxA1 to act both as a therapeutic and a prophylactic drug via its ability to promote endogenous proresolving, antithromboinflammatory circuits in cerebral I/RI. Collectively, these results further advance our knowledge and understanding in the field of platelet and resolution biology.Fil: Senchenkova, Elena Y.. State University of Louisiana; Estados UnidosFil: Ansari, Junaid. State University of Louisiana; Estados UnidosFil: Becker, Felix. University Hospital Muenster; AlemaniaFil: Vital, Shantel A.. State University of Louisiana; Estados UnidosFil: Al-Yafeai, Zaki. State University of Louisiana; Estados UnidosFil: Sparkenbaugh, Erica M.. University North Carolina Chapel Hill; Estados UnidosFil: Pawlinski, Rafal. University North Carolina Chapel Hill; Estados UnidosFil: Stokes, Karen Y.. State University of Louisiana; Estados UnidosFil: Carroll, Jennifer L.. State University of Louisiana; Estados UnidosFil: Dragoi, Ana-Maria. State University of Louisiana; Estados UnidosFil: Qin, Cheng Xue. Baker Heart And Diabetes Institute; AustraliaFil: Ritchie, Rebecca H.. Baker Heart And Diabetes Institute; AustraliaFil: Sun, Hai. University Hospital Muenster; AlemaniaFil: Cuellar-Saenz, Hugo H.. State University of Louisiana; Estados UnidosFil: Rubinstein Guichon, Mara Roxana. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; Argentina. Columbia University; Estados UnidosFil: Han, Yiping W.. Columbia University; Estados UnidosFil: Orr, A. Wayne. University Hospital Muenster; AlemaniaFil: Perretti, Mauro. Queen Mary University Of London; Reino UnidoFil: Granger, D. Neil. State University of Louisiana; Estados UnidosFil: Gavins, Felicity N.E.. State University of Louisiana; Estados Unido
All-cause mortality benefit of coronary revascularization vs. medical therapy in patients without known coronary artery disease undergoing coronary computed tomographic angiography: results from CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry)
Aims To date, the therapeutic benefit of revascularization vs. medical therapy for stable individuals undergoing invasive coronary angiography (ICA) based upon coronary computed tomographic angiography (CCTA) findings has not been examined. Methods and results We examined 15 223 patients without known coronary artery disease (CAD) undergoing CCTA from eight sites and six countries who were followed for median 2.1 years (interquartile range 1.4-3.3 years) for an endpoint of all-cause mortality. Obstructive CAD by CCTA was defined as a ≥50% luminal diameter stenosis in a major coronary artery. Patients were categorized as having high-risk CAD vs. non-high-risk CAD, with the former including patients with at least obstructive two-vessel CAD with proximal left anterior descending artery involvement, three-vessel CAD, and left main CAD. Death occurred in 185 (1.2%) patients. Patients were categorized into two treatment groups: revascularization (n = 1103; 2.2% mortality) and medical therapy (n = 14 120, 1.1% mortality). To account for non-randomized referral to revascularization, we created a propensity score developed by logistic regression to identify variables that influenced the decision to refer to revascularization. Within this model (C index 0.92, χ2 = 1248, P < 0.0001), obstructive CAD was the most influential factor for referral, followed by an interaction of obstructive CAD with pre-test likelihood of CAD (P = 0.0344). Within CCTA CAD groups, rates of revascularization increased from 3.8% for non-high-risk CAD to 51.2% high-risk CAD. In multivariable models, when compared with medical therapy, revascularization was associated with a survival advantage for patients with high-risk CAD [hazards ratio (HR) 0.38, 95% confidence interval 0.18-0.83], with no difference in survival for patients with non-high-risk CAD (HR 3.24, 95% CI 0.76-13.89) (P-value for interaction = 0.03). Conclusion In an intermediate-term follow-up, coronary revascularization is associated with a survival benefit in patients with high-risk CAD by CCTA, with no apparent benefit of revascularization in patients with lesser forms of CA
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