Investigating The Effects Of Obesity On Cardiovascular Reactivity And Recovery From Acute Physical And Psychological Stress

The role that excess adipose tissue plays in chronic inflammation gives rise to its importance as an independent risk factor in cardiovascular dysfunction. By operationalizing chronic stress as obesity, we sought to explore the relationship between obesity and cardiovascular responses to laboratory stressors, including recovery from stress. Further, we examined five adiposity measures to determine which were most related to cardiovascular dysfunction. Degree of obesity was able to predict dysfunction in both reactivity and recovery. Body mass index and waist circumference were found to be the best predictors of cardiovascular dysfunction. Blunted reactivity and slorecovery were found in participants with greater levels of adiposity

Obesity Related Perturbations On Cardiovascular, Immune And Endocrine Response To Active And Passive Stress

As the obesity epidemic increases, the prevalence of obesity-related diseases grows simultaneously. The internal environment of chronic low-grade inflammation, which characterizes obesity, leaves individuals vulnerable to disease. Cardiovascular dysfunction represents a consequential effect of obesity. An early indicator of cardiovascular disease is an impaired stress response. Further, the type of stress (active versus passive) may be differentially affected representing additional distinctions in impairment. In the present study, we have used two types of stress (active and passive) to investigate obesity-instigated alterations in cardiovascular, immune and endocrine response to stress. In addition, we have evaluated how these systems may overlap to perpetuate a potentially damaging stress response. Based on correlations used to determine relationships among the cardiovascular, immune and endocrine system we found that obese and non-obese groups responded similarly to active stress. However, the obese group exhibited blunted cardiovascular recovery following active stress. Conversely, the obese and non-obese groups responded differently to passive stress with the obese group demonstrating an overall greater stress response. This response included exaggerated reactivity of both the cardiovascular and endocrine systems. This suggests a possible link in obese individuals between the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis when activated in response to passive stress. These results indicate that the presentation of an abnormal stress response may occur at different times based on the type of stress. In response to passive stress, obese individuals show an exaggerated stress response; whereas the impairment associated with active stress appears during recovery

Factors Responsible for Healthcare Avoidance Among Rural Adults in the Eastern Region of North Carolina

PURPOSE: Previous research has identified three common reasons for healthcare avoidance, cost, complexity, and privacy. This study extends prior work by examining the antecedents to these barriers and determining the extent to which they contribute to healthcare avoidance in a rural population. METHODS: A cross-sectional, regional survey of rural residents from Eastern North Carolina was conducted with questions focused on self-perceived health, healthcare utilization, and healthcare avoidance. Bivariate logistic regression was employed to investigate the predictors of cost, complexity, and privacy-related avoidance. RESULTS: Among 946 respondents, a quarter of the sample (N = 240) had not visited a doctor within the past year. Respondents who were uninsured were almost 6-times more likely to endorse avoiding healthcare due to cost (OR = 5.98) and those who had a chronic illness were 3-times as likely to report cost-related avoidance (OR = 3.01). Complexity-related avoidance was predicted by having a chronic illness (OR = 3.77) and a low perception of healthcare value (OR = 2.80). Lastly, privacy-related avoidance was related to being in fair/poor health (OR = 2.61), having a chronic illness (OR = 2.63), reporting low healthcare value (OR = 2.72), and having an external locus of control (OR = 2.96). CONCLUSIONS: Among avoidant individuals, those with a chronic illness, who could benefit most from continuity of healthcare, are 3-times more likely to avoid healthcare due to cost, complexity, and privacy. The perceived value of healthcare is also associated with complexity- and privacy-related healthcare avoidance. Utilizing alternative methods of healthcare delivery, such as telemedicine and free or reduced cost mobile health clinics, could improve continuity of medical care for rural residents

Physical activity is reduced prior to ventricular arrhythmiasin patients with a wearable cardioverter defibrillator

The utility of accelerometer�based activity data to identify patients at risk of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) has not previously been investigated. The aim of the current study was to determine whether physical activity is associated with manifesting spontaneous sustained VT/VF requiring emergent defibrillation in patients with an ejection fraction of ≤35%

Silk-Cellulose Acetate Biocomposite Materials Regenerated from Ionic Liquid

The novel use of ionic liquid as a solvent for biodegradable and natural organic biomaterials has increasingly sparked interest in the biomedical field. As compared to more volatile traditional solvents that rapidly degrade the protein molecular weight, the capability of polysaccharides and proteins to dissolve seamlessly in ionic liquid and form fine and tunable biomaterials after regeneration is the key interest of this study. Here, a blended system consisting of Bombyx Mori silk fibroin protein and a cellulose derivative, cellulose acetate (CA), in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIMAc) was regenerated and underwent characterization to understand the structure and physical properties of the films. The change in the morphology of the biocomposites (by scanning electron microscope, SEM) and their secondary structure analysis (by Fourier-transform infrared spectroscopy, FTIR) showed that the samples underwent a wavering conformational change on a microscopic level, resulting in strong interactions and changes in their crystalline structures such as the CA crystalline and silk beta-pleated sheets once the different ratios were applied. Differential scanning calorimetry (DSC) results demonstrated that strong molecular interactions were generated between CA and silk chains, providing the blended films lower glass transitions than those of the pure silk or cellulose acetate. All films that were blended had higher thermal stability than the pure cellulose acetate sample but presented gradual changes amongst the changing of ratios, as demonstrated by thermogravimetric analysis (TGA). This study provides the basis for the comprehension of the protein-polysaccharide composites for various biomedical applications

A Genome-wide RNA Interference Screen Reveals that Variant Histones Are Necessary for Replication-Dependent Histone Pre-mRNA Processing

Metazoan replication-dependent histone mRNAs are not polyadenylated and instead end in a conserved stem loop that is the cis element responsible for coordinate posttranscriptional regulation of these mRNAs. Using biochemical approaches, only a limited number of factors required for cleavage of histone pre-mRNA have been identified. We therefore performed a genome-wide RNA interference screen in Drosophila cells using a GFP reporter that is expressed only when histone pre-mRNA processing is disrupted. Four of the 24 genes identified encode proteins also necessary for cleavage/polyadenylation, indicating mechanistic conservation in formation of different mRNA 3' ends. We also unexpectedly identified the histone variants H2Av and H3.3A/B. In H2Av mutant cells, U7 snRNP remains active but fails to accumulate at the histone locus, suggesting there is a regulatory pathway that coordinates the production of variant and canonical histones that acts via localization of essential histone pre-mRNA processing factors

Sex Differences in Arrhythmic Burden with the Wearable Cardioverter-Defibrillator

Background: Data on the arrhythmic burden of women at risk for sudden cardiac death are limited, especially in patients using the wearable cardioverter-defibrillator (WCD). Objective: We aimed to characterize WCD compliance, atrial and ventricular arrhythmic burden, and WCD outcomes by sex in patients enrolled in the Prospective Registry of Patients Using the Wearable Cardioverter Defibrillator (WEARIT-II U.S. Registry). Methods: In the WEARIT-II Registry, we stratified 2000 patients by sex into women (n = 598) and men (n = 1402). WCD wear time, ventricular and atrial arrhythmic events during WCD use, and implantable cardioverter-defibrillator (ICD) implantation rates at the end of WCD use were evaluated. Results: The mean WCD wear time was similar in women and men (94 days vs 90 days; P = .145), with longer daily use in women (21.4 h/d vs 20.7 h/d; P = .001). Burden of ventricular tachycardia or ventricular fibrillation was higher in women, with 30 events per 100 patient-years compared with 18 events per 100 patient-years in men (P = .017), with similar findings for treated and non-treated ventricular tachycardia/ventricular fibrillation. Recurrent atrial arrhythmias/sustained ventricular tachycardia was also more frequent in women than in men (167 events per 100 patient-years vs 73 events per 100 patient-years; P = .042). However, ICD implantation rate at the end of WCD use was similar in both women and men (41% vs 39%; P = .448). Conclusion: In the WEARIT-II Registry, we have shown a higher burden of ventricular and atrial arrhythmic events in women than in men. ICD implantation rates at the end of WCD use were similar. Our findings warrant monitoring women at risk for sudden cardiac death who have a high burden of atrial and ventricular arrhythmias while using the WCD

U7 snRNA mutations in Drosophila block histone pre-mRNA processing and disrupt oogenesis

Metazoan replication-dependent histone mRNAs are not polyadenylated, and instead terminate in a conserved stem–loop structure generated by an endonucleolytic cleavage involving the U7 snRNP, which interacts with histone pre-mRNAs through base-pairing between U7 snRNA and a purine-rich sequence in the pre-mRNA located downstream of the cleavage site. Here we generate null mutations of the single Drosophila U7 gene and demonstrate that U7 snRNA is required in vivo for processing all replication-associated histone pre-mRNAs. Mutation of U7 results in the production of poly A+ histone mRNA in both proliferating and endocycling cells because of read-through to cryptic polyadenylation sites found downstream of each Drosophila histone gene. A similar molecular phenotype also results from mutation of Slbp, which encodes the protein that binds the histone mRNA 3′ stem–loop. U7 null mutants develop into sterile males and females, and these females display defects during oogenesis similar to germ line clones of Slbp null cells. In contrast to U7 mutants, Slbp null mutations cause lethality. This may reflect a later onset of the histone pre-mRNA processing defect in U7 mutants compared to Slbp mutants, due to maternal stores of U7 snRNA. A double mutant combination of a viable, hypomorphic Slbp allele and a viable U7 null allele is lethal, and these double mutants express polyadenylated histone mRNAs earlier in development than either single mutant. These data suggest that SLBP and U7 snRNP cooperate in the production of histone mRNA in vivo, and that disruption of histone pre-mRNA processing is detrimental to development