253 research outputs found
B-mode ultrasound common carotid artery intima-media thickness and external diameter: cross-sectional and longitudinal associations with carotid atherosclerosis in a large population sample
<p>Abstract</p> <p>Background</p> <p>Arterial diameter and intima-media thickness (IMT) enlargement may each be related to the atherosclerotic process. Their separate or combined enlargement may indicate different arterial phenotypes with different atherosclerosis risk.</p> <p>Methods</p> <p>We investigated cross-sectional (baseline 1987–89: n = 7956) and prospective (median follow-up = 5.9 years: n = 4845) associations between baseline right common carotid artery (RCCA) external diameter and IMT with existing and incident carotid atherosclerotic lesions detected by B-mode ultrasound in any right or left carotid segments. Logistic regression models (unadjusted, adjusted for IMT, or adjusted for IMT and risk factors) were used to relate baseline diameter to existing carotid lesions while comparably adjusted parametric survival models assessed baseline diameter associations with carotid atherosclerosis progression (incident carotid lesions). Four baseline arterial phenotypes were categorized as having 1) neither IMT nor diameter enlarged (reference), 2) isolated IMT thickening, 3) isolated diameter enlargement, and 4) enlargement of both IMT and diameter. The association between these phenotypes and progression to definitive carotid atherosclerotic lesions was assessed over the follow-up period.</p> <p>Results</p> <p>Each standard deviation increment of baseline RCCA diameter was associated with increasing carotid lesion prevalence (unadjusted odds ratio [OR] = 1.54, 95% confidence interval [CI] = 1.47–1.62) and with progression of carotid atherosclerosis (unadjusted hazards ratio (HR) = 1.37, 95% CI = 1.28–1.46); and the associations remained significant even after adjustment for IMT and risk factors (prevalence OR = 1.11, 95% CI = 1.04–1.18; progression HR = 1.11, 95% CI = 1.03–1.19). Controlling for gender, age and race, persons with both RCCA IMT and diameter in the upper 50<sup>th </sup>percentiles had the greatest risk of progressing to clearly defined carotid atherosclerotic lesions (all HR = 1.71, 95% CI = 1.47–2.0; men HR = 1.88, 95% CI = 1.48–2.39; women HR = 1.59, 95% CI = 1.31–1.95) while RCCA IMT or diameter alone in the upper 50<sup>th </sup>percentile produced significantly lower estimated risks.</p> <p>Conclusion</p> <p>RCCA IMT and external diameter provide partially overlapping information relating to carotid atherosclerotic lesions. More importantly, the RCCA phenotype of coexistent wall thickening with external diameter enlargement indicates higher atherosclerotic risk than isolated wall thickening or diameter enlargement.</p
Author Correction: Early pregnancy ultrasound measurements and prediction of first trimester pregnancy loss: A logistic model (Scientific Reports, (2020), 10, 1, (1545), 10.1038/s41598-020-58114-3)
The original version of this Article contained an error in the spelling of the author Patricia J. Goedecke which was incorrectly given as Patricia J. Goeske. The original Article has been corrected
Implantation of Mouse Embryonic Stem Cell-Derived Cardiac Progenitor Cells Preserves Function of Infarcted Murine Hearts
Stem cell transplantation holds great promise for the treatment of myocardial infarction injury. We recently described the embryonic stem cell-derived cardiac progenitor cells (CPCs) capable of differentiating into cardiomyocytes, vascular endothelium, and smooth muscle. In this study, we hypothesized that transplanted CPCs will preserve function of the infarcted heart by participating in both muscle replacement and neovascularization. Differentiated CPCs formed functional electromechanical junctions with cardiomyocytes in vitro and conducted action potentials over cm-scale distances. When transplanted into infarcted mouse hearts, CPCs engrafted long-term in the infarct zone and surrounding myocardium without causing teratomas or arrhythmias. The grafted cells differentiated into cross-striated cardiomyocytes forming gap junctions with the host cells, while also contributing to neovascularization. Serial echocardiography and pressure-volume catheterization demonstrated attenuated ventricular dilatation and preserved left ventricular fractional shortening, systolic and diastolic function. Our results demonstrate that CPCs can engraft, differentiate, and preserve the functional output of the infarcted heart
Bilateral common carotid artery ultrasound for prediction of incident strokes using intima-media thickness and external diameter: an observational study
Abstract: Background: External common carotid artery (CCA) diameter and intima-media thickness (IMT) are independently associated with incident stroke and other cardiovascular events. Arterial geometry such as large IMT and large diameter may reflect vulnerable plaques and so impact stroke risk. Finally, arterial changes that exist bilaterally may increase stroke risk. Method: We studied middle-aged men and women (n=7276) from a prospective observational study who had right (R) and left (L) CCA IMT and external diameters measured via B-mode ultrasound (1987–89) in order to categorize CCA geometry. Using side- and gender-specific IMT and diameter medians, we categorized each measurement as large (≥ median) vs. not large (< median) and defined four geometries: both IMT and diameter were large, only one parameter was large, or neither was large (reference group). Participants were followed for first time stroke through December 31, 1999. We used proportional hazards models to assess associations between right and left CCA geometries with new stroke. We also calculated positive and negative likelihood ratios (+LR and -LR) for CCA bilateral phenotypes as a measure of diagnostic accuracy. Results: Presence of both large CCA IMT and large diameter on one side was associated with strong stroke risk even after risk factor adjustment (men: RCCA hazard ratio [HR]=3.7 95% confidence interval [CI]=1.9-7.4; LCCA HR=2.4 95% CI=1.4-4.4; women: RCCA HR=4.0 95% CI=1.5-10.5; LCCA HR=5.7 95% CI=1.7-19.0). Presence of both large IMT and large diameter bilaterally was the strongest predictor of stroke identifying 64% of women and 44% of men who developed strokes. This phenotype showed potential for predicting stroke among individuals (women: +LR=3.1, 95% CI=2.6-3.8; men: +LR=2.3, 95% CI=1.8-2.8). Conclusion: Bilateral carotid artery geometries may be useful for stroke risk prediction
Common carotid artery wall thickness and external diameter as predictors of prevalent and incident cardiac events in a large population study
Abstract Background Arterial diameters enlarge in response to wall thickening, plaques, and many atherosclerotic risk factors. We hypothesized that right common carotid artery (RCCA) diameter would be independently associated with cardiac disease and improve risk discrimination. Methods In a middle-aged, biracial population (baseline n = 11225), we examined associations between 1 standard deviation increments of baseline RCCA diameter with prevalent myocardial infarction (MI) and incident cardiac events (MI or cardiac death) using logistic regression and Cox proportional hazards models, respectively. Areas under the receiver operator characteristic curve (AUC) were used to estimate model discrimination. Results MI was present in 451 (4%) participants at baseline (1987–89), and incident cardiac events occurred among 646 (6%) others through 1999. Adjusting for IMT, RCCA diameter was associated with prevalent MI (female OR = 2.0, 95%CI = 1.61–2.49; male OR = 1.16, 95% CI = 1.04–1.30) and incident cardiac events (female HR = 1.75, 95% CI = 1.51–2.02; male HR = 1.27, 95% CI = 1.15–1.40). Associations were attenuated but persisted after adjustment for risk factors (not including IMT) (prevalent MI: female OR = 1.73, 95% CI = 1.40–2.14; male OR = 1.14, 95% CI = 1.02–1.28, and incident cardiac events: female HR = 1.26, 95% CI = 1.08–1.48; male HR = 1.19, 95% CI = 1.08–1.32). After additional adjustment for IMT, diameter was associated with incident cardiac events in women (HR = 1.18, 95% CI = 1.00–1.40) and men (HR = 1.17, 95% CI = 1.06–1.29), and with prevalent MI only in women (OR = 1.73; 95% CI = 1.37–2.17). In women, when adjustment was limited, diameter models had larger AUC than other models. Conclusion RCCA diameter is an important correlate of cardiac events, independent of IMT, but adds little to overall risk discrimination after risk factor adjustment
Common carotid arterial interadventitial distance (diameter) as an indicator of the damaging effects of age and atherosclerosis, a cross-sectional study of the Atherosclerosis Risk in Community Cohort Limited Access Data (ARICLAD), 1987-89
Abstract: Background: The effect of age on common carotid artery diameter is unclear for varying atherosclerosis risk levels. Methods: Cross-sectional data from the Atherosclerosis Risk in Communities Limited Access Data set were used to estimate the association of age with B-mode ultrasound common carotid artery diameter for three atherosclerosis risk levels. Based on information from clinical examinations, B-mode ultrasounds, questionnaires, blood and other tests, participants were categorized into three groups: pre-existing disease (prevalent stroke and/or coronary heart disease), high risk group (no pre-existing disease, but prevalent diabetes, hypertension, plaques/ shadowing, body mass index >= 30, current smoking, or hyperlipidemia), and a low risk group (no pre-existing disease, no plaques/shadowing, and no major elevated risk factors). Multivariable linear regression analyses modeled the common carotid artery diameter relationship with age. Results: Age was positively and significantly associated with common carotid artery diameter after risk factor adjustment in the overall sample, but age had a larger effect among persons with evidence of atherosclerosis (interaction p < 0.05). Each year of older age was associated with 0.03 mm larger diameter/year among persons with pre-existing disease, with 0.027 mm larger diameter/ year in the high risk group, but only 0.017 mm/year among the low risk group. Results were qualitatively similar using plaques/shadowing status to indicate atherosclerosis severity. Conclusion: The significant impact of age on common carotid artery diameter among low risk, middle-aged, black and white men and women suggests arterial remodelling may occur in the absence of identified risk factors. The significantly larger impact of age among persons with, compared to persons without identified atherosclerosis or its risk factors, suggests that arterial remodelling may be an indicator of exposure duration
X-Linked Inhibitor of Apoptosis Protein-Mediated Attenuation of Apoptosis, Using a Novel Cardiac-Enhanced Adeno-Associated Viral Vector
Successful amelioration of cardiac dysfunction and heart failure through gene therapy approaches will require a transgene effective at attenuating myocardial injury, and subsequent remodeling, using an efficient and safe delivery vehicle. Our laboratory has established a well-curated, high-quality repository of human myocardial tissues that we use as a discovery engine to identify putative therapeutic transgene targets, as well as to better understand the molecular basis of human heart failure. By using this rare resource we were able to examine age- and sex-matched left ventricular samples from (1) end-stage failing human hearts and (2) nonfailing human hearts and were able to identify the X-linked inhibitor of apoptosis protein (XIAP) as a novel target for treating cardiac dysfunction. We demonstrate that XIAP is diminished in failing human hearts, indicating that this potent inhibitor of apoptosis may be central in protecting the human heart from cellular injury culminating in heart failure. Efforts to ameliorate heart failure through delivery of XIAP compelled the design of a novel adeno-associated viral (AAV) vector, termed SASTG, that achieves highly efficient transduction in mouse heart and in cultured neonatal rat cardiomyocytes. Increased XIAP expression achieved with the SASTG vector inhibits caspase-3/7 activity in neonatal cardiomyocytes after induction of apoptosis through three common cardiac stresses: protein kinase C-γ inhibition, hypoxia, or β-adrenergic receptor agonist. These studies demonstrate the potential benefit of XIAP to correct heart failure after highly efficient delivery to the heart with the rationally designed SASTG AAV vector
A novel small molecule target in human airway smooth muscle for potential treatment of obstructive lung diseases: a staged high-throughput biophysical screening
<p>Abstract</p> <p>Background</p> <p>A newly identified mechanism of smooth muscle relaxation is the interaction between the small heat shock protein 20 (HSP20) and 14-3-3 proteins. Focusing upon this class of interactions, we describe here a novel drug target screening approach for treating airflow obstruction in asthma.</p> <p>Methods</p> <p>Using a high-throughput fluorescence polarization (FP) assay, we screened a library of compounds that could act as small molecule modulators of HSP20 signals. We then applied two quantitative, cell-based biophysical methods to assess the functional efficacy of these molecules and rank-ordered their abilities to relax isolated human airway smooth muscle (ASM). Scaling up to the level of an intact tissue, we confirmed in a concentration-responsive manner the potency of the cell-based hit compounds.</p> <p>Results</p> <p>Among 58,019 compound tested, 268 compounds caused 20% or more reduction of the polarized emission in the FP assay. A small subset of these primary screen hits, belonging to two scaffolds, caused relaxation of isolated ASM cell <it>in vitro </it>and attenuated active force development of intact tissue <it>ex vivo</it>.</p> <p>Conclusions</p> <p>This staged biophysical screening paradigm provides proof-of-principle for high-throughput and cost-effective discovery of new small molecule therapeutic agents for obstructive lung diseases.</p
Generation of ribosome imprinted polymers for sensitive detection of translational responses
Whilst the profiling of the transcriptome and proteome even of single-cells becomes feasible, the analysis of the translatome, which refers to all messenger RNAs (mRNAs) engaged with ribosomes for protein synthesis, is still an elaborate procedure requiring millions of cells. Herein, we report the generation and use of “smart materials”, namely molecularly imprinted polymers (MIPs) to facilitate the isolation of ribosomes and translated mRNAs from merely 1,000 cells. In particular, we show that a hydrogel-based ribosome imprinted polymer could recover ribosomes and associated mRNAs from human, simian and mice cellular extracts, but did not selectively enrich yeast ribosomes, thereby demonstrating selectivity. Furthermore, ribosome imprinted polymers enabled the sensitive measurement of an mRNA translational regulatory event, requiring 1,000-fold less cells than current methodologies. These results provide first evidence for the suitability of MIPs to selectively recover ribonucleoprotein complexes such as ribosomes, founding a novel means for sensitive detection of gene regulation
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