Arterial Ventricular Uncoupling With Age and Disease and Recoupling With Exercise

The deterioration in arterial and cardiac function with aging impairs arterial ventricular coupling, an important determinant of cardiovascular performance. However, exercise training improves arterial ventricular coupling especially during exercise during the age and disease process. This review examines the concept of arterial-ventricular coupling, and how age, and disease uncouples but exercise training recouples the heart and arterial system

Interactions between Silica Particles in the Presence of Multivalent Coions

Forces between charged silica particles in solutions of multivalent coions are measured with colloidal probe technique based on atomic force microscopy. The concentration of 1:z electrolytes is systematically varied to understand the behavior of electrostatic interactions and double-layer properties in these systems. Although the coions are multivalent the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory perfectly describes the measured force profiles. The diffuse-layer potentials and regulation properties are extracted from the forces profiles by using the DLVO theory. The dependencies of the diffuse-layer potential and regulation parameter shift to lower concentration with increasing coion valence when plotted as a function of concentration of 1:z salt. Interestingly, these profiles collapse to a master curve if plotted as a function of monovalent counterion concentration

Arterial–Ventricular Coupling with Aging and Disease

Age is the dominant risk factor for cardiovascular diseases. Understanding the coupling between the left ventricle (LV) and arterial system, termed arterial–ventricular coupling (EA/ELV), provides important mechanistic insights into the complex cardiovascular system and its changes with aging in the absence and presence of disease. EA/ELV can be indexed by the ratio of effective arterial elastance (EA; a measure of the net arterial load exerted on the LV) to left ventricular end-systolic elastance (ELV; a load-independent measure of left ventricular chamber performance). Age-associated alterations in arterial structure and function, including diameter, wall thickness, wall stiffness, and endothelial dysfunction, contribute to a gradual increase in resting EA with age. Remarkably there is a corresponding increase in resting ELV with age, due to alterations to LV remodeling (loss in myocyte number, increased collagen) and function. These age-adaptations at rest likely occur, at least, in response to the age-associated increase in EA and ensure that EA/ELV is closely maintained within a narrow range, allowing for optimal energetic efficiency at the expense of mechanical efficacy. This optimal coupling at rest is also maintained when aging is accompanied by the presence of hypertension, and obesity, despite further increases in EA and ELV in these conditions. In contrast, in heart failure patients with either reduced or preserved ejection fraction, EA/ELV at rest is impaired. During dynamic exercise, EA/ELV decreases, due to an acute mismatch between the arterial and ventricular systems as ELV increases disproportionate compared to EA (≈200 vs. 40%), to ensure that sufficient cardiac performance is achieved to meet the increased energetic requirements of the body. However, with advancing age the reduction in EA/ELV during acute maximal exercise is blunted, due to a blunted increase ELV. This impaired EA/ELV is further amplified in the presence of disease, and may explain, in part, the reduced cardiovascular functional capacity with age and disease. Thus, although increased stiffness of the arteries itself has important physiological and clinical relevance, such changes also have major implications on the heart, and vice versa, and the manner in the way they interact has important ramifications on cardiovascular function both at rest and during exercise. Examination of the alterations in arterial–ventricular coupling with aging and disease can yield mechanistic insights into the pathophysiology of these conditions and increase the effectiveness of current therapeutic interventions

Do GPs want or need formal support following a patient suicide?: a mixed methods study.

BACKGROUND: Patient suicide can be a devastating event for some general practitioners (GPs). Few guidelines exist to aid or support GPs in the aftermath of patient suicide. AIM: To explore GPs views on how they are affected by a patient suicide and the formal support available to them following a patient suicide. DESIGN: Questionnaires and semi-structured interviews. SETTING: General practices in the northwest of England. METHODS: About 198 semi-structured interviews were conducted as part of a retrospective study. Interviews were transcribed verbatim and analysed using descriptive statistics and a framework thematic approach. RESULTS: GPs were aged between 31 and 67 years, 144 (73%) were male and the number of years in practice varied between 8 and 40 years (median = 24 years). GPs were based at 133 (67%) urban and 65 (33%) rural practices, 30 (15%) were single-handed GP practices and 168 (85%) practices had two or more GPs. About 131 (66%) GPs reported being affected by patient suicide through feelings of grief, guilt and self-scrutiny. A greater number of years in practice may have been protective against these effects. About 54 (27%) GPs reported having mostly 'informal' support from peers or colleagues and support was less available to younger and single handed GPs. CONCLUSIONS: Our findings suggest that the majority of GPs are affected by patient suicide and most seek informal support from their peers and colleagues. Although many indicated that informal support systems were adequate and provided a protective environment, procedures should be developed to ensure the availability of guidelines for those who may require formal support

Stroke-associated pattern of gene expression previously identified by machine-learning is diagnostically robust in an independent patient population

Our group recently employed genome-wide transcriptional profiling in tandem with machine-learning based analysis to identify a ten-gene pattern of differential expression in peripheral blood which may have utility for detection of stroke. The objective of this study was to assess the diagnostic capacity and temporal stability of this stroke-associated transcriptional signature in an independent patient population. Publicly available whole blood microarray data generated from 23 ischemic stroke patients at 3, 5, and 24 h post-symptom onset, as well from 23 cardiovascular disease controls, were obtained via the National Center for Biotechnology Information Gene Expression Omnibus. Expression levels of the ten candidate genes (ANTXR2, STK3, PDK4, CD163, MAL, GRAP, ID3, CTSZ, KIF1B, and PLXDC2) were extracted, compared between groups, and evaluated for their discriminatory ability at each time point. We observed a largely identical pattern of differential expression between stroke patients and controls across the ten candidate genes as reported in our prior work. Furthermore, the coordinate expression levels of the ten candidate genes were able to discriminate between stroke patients and controls with levels of sensitivity and specificity upwards of 90% across all three time points. These findings confirm the diagnostic robustness of the previously identified pattern of differential expression in an independent patient population, and further suggest that it is temporally stable over the first 24 h of stroke pathology

Defining operational strengths and gaps relevant to post licensure Group B Streptococcus vaccine effectiveness studies: an expert stakeholder evaluation of the United Kingdom and Uganda

A future Group B Streptococcal (GBS) vaccine for pregnant women to protect neonates is likely to be licensed based on evidence of vaccine induced protective antibody levels. Post licensure surveillance to monitor the impact of any future vaccine on GBS disease therefore needs to be clearly defined (in both high and low income settings). A priority research gap is understanding health system preparedness for a GBS vaccine evaluation This expert stakeholder evaluation aimed to describe the UK and Uganda's operational strengths and gaps relevant to post-licensure GBS vaccine studies

Can Deep Water Exercise Training Improve Arterial Stiffness in Women with Metabolic Syndrome?

Please refer to the pdf version of the abstract located adjacent to the title