Biophysical analysis of HTLV-1 particles reveals novel insights into particle morphology and Gag stoichiometry

<p>Abstract</p> <p>Background</p> <p>Human T-lymphotropic virus type 1 (HTLV-1) is an important human retrovirus that is a cause of adult T-cell leukemia/lymphoma. While an important human pathogen, the details regarding virus replication cycle, including the nature of HTLV-1 particles, remain largely unknown due to the difficulties in propagating the virus in tissue culture. In this study, we created a codon-optimized HTLV-1 Gag fused to an <it>EYFP </it>reporter as a model system to quantitatively analyze HTLV-1 particles released from producer cells.</p> <p>Results</p> <p>The codon-optimized Gag led to a dramatic and highly robust level of Gag expression as well as virus-like particle (VLP) production. The robust level of particle production overcomes previous technical difficulties with authentic particles and allowed for detailed analysis of particle architecture using two novel methodologies. We quantitatively measured the diameter and morphology of HTLV-1 VLPs in their native, hydrated state using cryo-transmission electron microscopy (cryo-TEM). Furthermore, we were able to determine HTLV-1 Gag stoichiometry as well as particle size with the novel biophysical technique of fluorescence fluctuation spectroscopy (FFS). The average HTLV-1 particle diameter determined by cryo-TEM and FFS was 71 ± 20 nm and 75 ± 4 nm, respectively. These values are significantly smaller than previous estimates made of HTLV-1 particles by negative staining TEM. Furthermore, cryo-TEM reveals that the majority of HTLV-1 VLPs lacks an ordered structure of the Gag lattice, suggesting that the HTLV-1 Gag shell is very likely to be organized differently compared to that observed with HIV-1 Gag in immature particles. This conclusion is supported by our observation that the average copy number of HTLV-1 Gag per particle is estimated to be 510 based on FFS, which is significantly lower than that found for HIV-1 immature virions.</p> <p>Conclusions</p> <p>In summary, our studies represent the first quantitative biophysical analysis of HTLV-1-like particles and reveal novel insights into particle morphology and Gag stochiometry.</p

Factors Associated with Medication Adherence Among a High-Risk Hepatitis C Birth Cohort

BACKGROUND: Multiple studies of hepatitis C virus (HCV) reported that 75% of individuals infected with HCV were born between 1945-1965 and were previously never tested. Therefore, in 2012 the CDC published recommendations that all individuals in this birth cohort should be screened for HCV at least once. Adherence to treatment is essential to achieve a sustained virologic response (SVR) for HCV cure. Patients who do not complete the treatment are at risk of treatment failure. The Adherence to Refills and Medication Scale (ARMS) has been an effective tool for predicting adherence of medication treatment in cardiovascular disease and diabetes and identifying risk factors associated with nonadherence to treatment for these diseases. The purpose of this study is to elucidate which risk factors significantly influence the ARMS score among this birth cohort at risk for HCV to guide future HCV treatment protocol adherence. METHODS: This study recruited patients born between 1945-1965 and accessing care at the OU Physicians-Tulsa Family Medicine clinic between March-July 2019. Data was collected using a prescreening survey consisting of demographics, questions related to HCV risk factors (blood transfusions, tattoos, and intravenous drug use), depression assessed with the PHQ9 tool, and adverse childhood experiences (ACEs). IVDU, ACEs, and PHQ9 were classified into groups. Mean ARMS scores were compared using t-tests for variables with two categories and analysis of variance for variables with three or more categories. All statistical analyses were performed in SAS 9.4. RESULTS: Among the 75 participants in the study, most were women (57%) and the sample had a mean ARMS score of 16.32 (SD=3.45). About half reported depression (51%) and one-third reported four or more ACEs (33%). Mean ARMS scores were 2.983 points (95% CI: 0.70-5.26) higher among those with moderate depression (PHQ 5-14), and 2.699 points (95% CI: 0.65-4.75) higher among those with severe depression (PHQ 15-27) than those with a minimal depression (PHQ 0-4). Similarly, mean ARMS score was 2.61 points (95% CI: 0.34-4.88) higher among those with at least four ACEs compared to those with three ACEs or less. Mean ARMS scores did not differ for any other variables. CONCLUSION: This is the first study to assess the ARMS score as a predictor of medication adherence and risk factors associated with the ARMS score in this high-risk birth cohort for HCV infection. These findings indicate that depression and ACEs may be risk factors for poor medication adherence in this population.N

Concert recording 2014-04-08

[Track 01]. Madama Butterfly. Un bel di vedremo / Glacomo Puccini -- [Track 02]. Hello again. Tom / Michael John LaCiusa -- [Track 03]. Mein schoner stern! (my lovely star) / Robert Schumann -- [Track 04]. Into the night / Robert Schumann -- [Track 05]. Per la Gloria / Giovanni B. Bonocirii -- [Track 06]. Bonjour, Suzon! / Leo Delibes -- [Track 07]. Die Winterreise. Erstarrung (numbness) / Franz Schubert -- [Track 08]. West Side Story. Something\u27s coming / Leonard Bernstein -- [Track 09]. Un ballo in maschera. Saper vorreste / Giuseppe Verdi -- [Track 10]. O del mio amato ben / Stefeno Donaudy -- [Track 11]. O del mio dolce ardor / Christoph W. von Gluck -- [Track 12]. My fair lady. I could have danced all night / Loewe & Lerner -- [Track 13]. Vergebliches standchen (The vain suit) / Johannes Brahms

Special Issue "On Defining Artificial Intelligence"—Commentaries and Author's Response

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Radiographic evaluation of calcaneal fractures: To measure or not to measure

Objective: The aim of this study was to correlate the functional outcome after treatment for displaced intra-articular calcaneal fracture with plain radiography. Design: The design was a prognostic study of a retrospective cohort with concurrent follow-up. Patients: A total of 33 patients with a unilateral calcaneal fracture and a minimum follow-up of 13 months participated. Patients filled in three disease-specific questionnaires, graded their satisfaction and the indication for an arthrodesis was noted. Standardised radiographs were made of the previously injured side and the normal (control) side. Different angles and distances were measured on these radiographs and compared with values described in the literature. The differences in values in angles and distances between the injured and uninjured (control) foot were correlated with the outcome of the questionnaires, and the indication for an arthrodesis. Results: None of the angles correlated with the disease-specific outcome scores. Of the angles only the tibiotalar angle correlated with the VAS (r=0.35, p=0.045) and only the absolute foot height correlated with the indication for an arthrodesis (odds=0.70, CI=0.50-0.99). Conclusion: In this study the radiographic evaluation correlated poorly with the final outcome. Measurements on plain radiographs seem not to be useful in determining outcome after intra-articular calcaneal fractures

Systemic Biomarkers of Neutrophilic Inflammation, Tissue Injury and Repair in COPD Patients with Differing Levels of Disease Severity

The identification and validation of biomarkers to support the assessment of novel therapeutics for COPD continues to be an important area of research. The aim of the current study was to identify systemic protein biomarkers correlated with measures of COPD severity, as well as specific protein signatures associated with comorbidities such as metabolic syndrome. 142 protein analytes were measured in serum of 140 patients with stable COPD, 15 smokers without COPD and 30 non-smoking controls. Seven analytes (sRAGE, EN-RAGE, NGAL, Fibrinogen, MPO, TGF-α and HB-EGF) showed significant differences between severe/very severe COPD, mild/moderate COPD, smoking and non-smoking control groups. Within the COPD subjects, univariate and multivariate analyses identified analytes significantly associated with FEV1, FEV1/FVC and DLCO. Most notably, a set of 5 analytes (HB-EGF, Fibrinogen, MCP-4, sRAGE and Sortilin) predicted 21% of the variability in DLCO values. To determine common functions/pathways, analytes were clustered in a correlation network by similarity of expression profile. While analytes related to neutrophil function (EN-RAGE, NGAL, MPO) grouped together to form a cluster associated with FEV1 related parameters, analytes related to the EGFR pathway (HB-EGF, TGF-α) formed another cluster associated with both DLCO and FEV1 related parameters. Associations of Fibrinogen with DLCO and MPO with FEV1/FVC were stronger in patients without metabolic syndrome (r  =  −0.52, p  = 0.005 and r  =  −0.61, p  = 0.023, respectively) compared to patients with coexisting metabolic syndrome (r  =  −0.25, p  = 0.47 and r  =  −0.15, p  = 0.96, respectively), and may be driving overall associations in the general cohort. In summary, our study has identified known and novel serum protein biomarkers and has demonstrated specific associations with COPD disease severity, FEV1, FEV1/FVC and DLCO. These data highlight systemic inflammatory pathways, neutrophil activation and epithelial tissue injury/repair processes as key pathways associated with COPD

Association of Low-Frequency and Rare Coding-Sequence Variants with Blood Lipids and Coronary Heart Disease in 56,000 Whites and Blacks

Low-frequency coding DNA sequence variants in the proprotein convertase subtilisin/kexin type 9 gene (PCSK9) lower plasma low-density lipoprotein cholesterol (LDL-C), protect against risk of coronary heart disease (CHD), and have prompted the development of a new class of therapeutics. It is uncertain whether the PCSK9 example represents a paradigm or an isolated exception. We used the “Exome Array” to genotype >200,000 low-frequency and rare coding sequence variants across the genome in 56,538 individuals (42,208 European ancestry [EA] and 14,330 African ancestry [AA]) and tested these variants for association with LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides. Although we did not identify new genes associated with LDL-C, we did identify four low-frequency (frequencies between 0.1% and 2%) variants (ANGPTL8 rs145464906 [c.361C>T; p.Gln121∗], PAFAH1B2 rs186808413 [c.482C>T; p.Ser161Leu], COL18A1 rs114139997 [c.331G>A; p.Gly111Arg], and PCSK7 rs142953140 [c.1511G>A; p.Arg504His]) with large effects on HDL-C and/or triglycerides. None of these four variants was associated with risk for CHD, suggesting that examples of low-frequency coding variants with robust effects on both lipids and CHD will be limited

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

An Interdepartmental Approach to Wellness Through Community Philanthropy

Resident physicians are a group especially vulnerable to burnout. Depersonalization is one of the main domains of burnout 1. We hypothesized that by fostering a sense of community to address feelings of depersonalization we could decrease burnout. We aimed to achieve this by improving collegiality among residents by asking them to work together toward a common goal, and by increasing resident engagement with their community by providing extramural philanthropic opportunities. The Neurology, Emergency Medicine and Internal Medicine departments have collaborated to plan three interdepartmental philanthropic events over the course of the year. The first of these was a dinner hosted by residents for families staying at the Ronald McDonald House. A clothing drive and trail clean-up are also planned