161 research outputs found
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Roles of estrogen receptor-alpha in mediating life span: the hypothalamic deregulation hypothesis.
In several species caloric restriction (CR) extends life span. In this paper we integrate data from studies on CR and other sources to articulate the hypothalamic deregulation hypothesis by which estrogen receptor-alpha (ER-α) signaling in the hypothalamus and limbic system affects life span under the stress of CR in mammals. ER-α is one of two principal estrogen-binding receptors differentially expressed in the amygdala, hippocampus, and several key hypothalamic nuclei: the arcuate nucleus (ARN), preoptic area (POA), ventromedial nucleus (VMN), antero ventral periventricular nucleus (AVPV), paraventricular nucleus (PVN), supraoptic nucleus (SON), and suprachiasmatic nucleus (SCN). Estradiol signaling via ER-α is essential in basal level functioning of reproductive cycle, sexually receptive behaviors, physiological stress responses, as well as sleep cycle, and other nonsexual behaviors. When an organism is placed under long-term CR, which introduces an external stress to this ER-α signaling, the reduction of ER-α expression is attenuated over time in the hypothalamus. This review paper seeks to characterize the downstream effects of ER-α in the hypothalamus and limbic system that affect normal endocrine functioning
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Correlating perceived arrhythmia symptoms and QoL in the elderly with Heart Failure in an urban clinic: A prospective, single center study
Aims and objectives
To determine the relationship between quality of life and perceived self-reported symptoms in an older, ambulatory, urban population living with heart failure.
Background
While arrhythmias in older individuals with heart failure are well documented, the association between perceived arrhythmia symptoms and quality of life is not well-defined.
Design
Prospective, cross-sectional single-centre study.
Methods
A single-centre, prospective study was conducted with heart failure patients recruited from an urban outpatient cardiology clinic in the United States. Fifty-seven patients completed a baseline quality of life survey with 42 of these completing the six-month follow-up survey. Quality of life was evaluated with the SF-36v2âą and frequency of symptoms with the Atrial Fibrillation Severity Scale. Subjects wore an auto triggered cardiac loop monitor (LifeStar AF ExpressÂź) for two weeks to document arrhythmias. Data analysis utilised Spearman's rank correlation and logistic regression.
Results
Baseline and six-month quality of life measures did not correlate with recorded arrhythmias. However, perceptions of diminished general health correlated significantly with symptoms of exercise intolerance, lightheadedness/dizziness, palpitations and chest pain/pressure. By multivariable logistic regression, more severe perceived episodes, symptoms of exercise intolerance and lightheadedness/dizziness were independently associated with diminished quality of life.
Conclusion
Quality of life was significantly worse in patients with perceptions of severe arrhythmic episodes and in those with symptoms of dizziness and exercise intolerance.
Relevance to clinical practice
The findings of this study indicate that symptomatic heart failure patients suffer from poor quality of life and that interventions are needed to improve quality of life and decrease symptom severity. Nurses who care for heart failure patients play an essential role in symptom evaluation and management and could significantly improve overall quality of life in these patients by carefully evaluating symptomatology and testing interventions and educational programmes aimed at improving quality of life
Mechanical Circulatory Support for Right Ventricular Failure
Right ventricular (RV) failure is associated with significant morbidity and mortality, with in-hospital mortality rates estimated as high as 70â75%. RV failure may occur following cardiac surgery in conjunction with left ventricular failure, or may be isolated in certain circumstances, such as inferior MI with RV infarction, pulmonary embolism or following left ventricular assist device placement. Medical management includes volume optimisation and inotropic and vasopressor support, and a subset of patients may benefit from mechanical circulatory support for persistent RV failure. Increasingly, percutaneous and surgical mechanical support devices are being used for RV failure. Devices for isolated RV support include percutaneous options, such as micro-axial flow pumps and extracorporeal centrifugal flow RV assist devices, surgically implanted RV assist devices and veno-arterial extracorporeal membrane oxygenation. In this review, the authors discuss the indications, candidate selection, strategies and outcomes of mechanical circulatory support for RV failure
Development of a Novel Echocardiography Ramp Test for Speed Optimization and Diagnosis of Device Thrombosis in Continuous-Flow Left Ventricular Assist Devices The Columbia Ramp Study
ObjectivesThis study sought to develop a novel approach to optimizing continuous-flow left ventricular assist device (CF-LVAD) function and diagnosing device malfunctions.BackgroundIn CF-LVAD patients, the dynamic interaction of device speed, left and right ventricular decompression, and valve function can be assessed during an echocardiography-monitored speed ramp test.MethodsWe devised a unique ramp test protocol to be routinely used at the time of discharge for speed optimization and/or if device malfunction was suspected. The patient's left ventricular end-diastolic dimension, frequency of aortic valve opening, valvular insufficiency, blood pressure, and CF-LVAD parameters were recorded in increments of 400 rpm from 8,000 rpm to 12,000 rpm. The results of the speed designations were plotted, and linear function slopes for left ventricular end-diastolic dimension, pulsatility index, and power were calculated.ResultsFifty-two ramp tests for 39 patients were prospectively collected and analyzed. Twenty-eight ramp tests were performed for speed optimization, and speed was changed in 17 (61%) with a mean absolute value adjustment of 424 ± 211 rpm. Seventeen patients had ramp tests performed for suspected device thrombosis, and 10 tests were suspicious for device thrombosis; these patients were then treated with intensified anticoagulation and/or device exchange/emergent transplantation. Device thrombosis was confirmed in 8 of 10 cases at the time of emergent device exchange or transplantation. All patients with device thrombosis, but none of the remaining patients had a left ventricular end-diastolic dimension slope >â0.16.ConclusionsRamp tests facilitate optimal speed changes and device malfunction detection and may be used to monitor the effects of therapeutic interventions and need for surgical intervention in CF-LVAD patients
Complete Hemodynamic Profiling With Pulmonary Artery Catheters in Cardiogenic Shock Is Associated With Lower In-Hospital Mortality
OBJECTIVES: The purpose of this study was to investigate the association between obtaining hemodynamic data from early pulmonary artery catheter (PAC) placement and outcomes in cardiogenic shock (CS).
BACKGROUND: Although PACs are used to guide CS management decisions, evidence supporting their optimal use in CS is lacking.
METHODS: The Cardiogenic Shock Working Group (CSWG) collected retrospective data in CS patients from 8 tertiary care institutions from 2016 to 2019. Patients were divided by Society for Cardiovascular Angiography and Interventions (SCAI) stages and outcomes analyzed by the PAC-use group (no PAC data, incomplete PAC data, complete PAC data) prior to initiating mechanical circulatory support (MCS).
RESULTS: Of 1,414 patients with CS analyzed, 1,025 (72.5%) were male, and 494 (34.9%) presented with myocardial infarction; 758 (53.6%) were in SCAI Stage D shock, and 263 (18.6%) were in Stage C shock. Temporary MCS devices were used in 1,190 (84%) of those in advanced CS stages. PAC data were not obtained in 216 patients (18%) prior to MCS, whereas 598 patients (42%) had complete hemodynamic data. Mortality differed significantly between PAC-use groups within the overall cohort (p \u3c 0.001), and each SCAI Stage subcohort (Stage C: p = 0.03; Stage D: p = 0.05; Stage E: p = 0.02). The complete PAC assessment group had the lowest in-hospital mortality than the other groups across all SCAI stages. Having no PAC assessment was associated with higher in-hospital mortality than complete PAC assessment in the overall cohort (adjusted odds ratio: 1.57; 95% confidence interval: 1.06 to 2.33).
CONCLUSIONS: The CSWG is a large multicenter registry representing real-world patients with CS in the contemporary MCS era. Use of complete PAC-derived hemodynamic data prior to MCS initiation is associated with improved survival from CS
Human Brain/Cloud Interface
The Internet comprises a decentralized global system that serves humanityâs collective effort to generate, process, and store data, most of which is handled by the rapidly expanding cloud. A stable, secure, real-time system may allow for interfacing the cloud with the human brain. One promising strategy for enabling such a system, denoted here as a âhuman brain/cloud interfaceâ (âB/CIâ), would be based on technologies referred to here as âneuralnanorobotics.â Future neuralnanorobotics technologies are anticipated to facilitate accurate diagnoses and eventual cures for the âŒ400 conditions that affect the human brain. Neuralnanorobotics may also enable a B/CI with controlled connectivity between neural activity and external data storage and processing, via the direct monitoring of the brainâs âŒ86 Ă 109 neurons and âŒ2 Ă 1014 synapses. Subsequent to navigating the human vasculature, three species of neuralnanorobots (endoneurobots, gliabots, and synaptobots) could traverse the bloodâbrain barrier (BBB), enter the brain parenchyma, ingress into individual human brain cells, and autoposition themselves at the axon initial segments of neurons (endoneurobots), within glial cells (gliabots), and in intimate proximity to synapses (synaptobots). They would then wirelessly transmit up to âŒ6 Ă 1016 bits per second of synaptically processed and encoded humanâbrain electrical information via auxiliary nanorobotic fiber optics (30 cm3) with the capacity to handle up to 1018 bits/sec and provide rapid data transfer to a cloud based supercomputer for real-time brain-state monitoring and data extraction. A neuralnanorobotically enabled human B/CI might serve as a personalized conduit, allowing persons to obtain direct, instantaneous access to virtually any facet of cumulative human knowledge. Other anticipated applications include myriad opportunities to improve education, intelligence, entertainment, traveling, and other interactive experiences. A specialized application might be the capacity to engage in fully immersive experiential/sensory experiences, including what is referred to here as âtransparent shadowingâ (TS). Through TS, individuals might experience episodic segments of the lives of other willing participants (locally or remote) to, hopefully, encourage and inspire improved understanding and tolerance among all members of the human family
Women, but not men, have prolonged QT interval if depressed after an acute coronary syndrome
Aims Depression is a mortality risk marker for acute coronary syndrome (ACS) patients. We hypothesized that the QT interval, a predictor for risk of sudden cardiac death, was related to depressive symptoms in ACS.
Methods and results We performed an analysis of admission electrocardiograms from hospitalized patients with unstable angina or non-ST elevation myocardial infarction from two prospective observational studies of depression in ACS. Depressive symptoms were assessed with the Beck Depression Inventory (BDI), and depression was defined as BDI score â„10, compared with <5. Patients with QRS duration â„120 ms and/or who were prescribed antidepressants were excluded. QT intervals were adjusted for heart rate by two methods. Our analyses included 243 men (40.0% with BDI â„10) and 139 women (62.0% with BDI â„ 10). Among women, average QT corrected by Fridericia's method (QTcF) was 435.4 ± 26.6 ms in the depressed group, vs. 408.6 ± 24.3 ms in the non-depressed group (P< 0.01). However, among men, average QTcF was not significantly different between the depressed and non-depressed groups (415.4 ± 23.6 vs. 412.0 ± 25.8 ms, P= 0.29). In multivariable analyses that included hypertension, diabetes, ACS type, left ventricular ejection fraction <0.40, and use of QT-prolonging medication, there was a statistically significant interaction between depressive symptoms and gender (P< 0.001).
Conclusions In this ACS sample, prolongation of the QT interval was associated with depressive symptoms in women, but not in men. Further investigation of the mechanism of the relationship between depression and abnormal cardiac repolarization, particularly in women, is warranted to develop treatment strategies
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