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The American Journal of Cardiology Feb 2024
Erratum to 'Acute Effect of Atrial Fibrillation on Circulating Natriuretic Peptides: The Influence of Heart Rate, Rhythm Irregularity, and Left Atrial Pressure Overload' [American Journal of Cardiology 208 (2023)156-163].
PubMed: 38134969
DOI: 10.1016/j.amjcard.2023.12.022 -
Science Advances Dec 2023Decadal and multidecadal changes in the meridional overturning circulation may originate from either the subpolar North Atlantic or the Southern Hemisphere. New records...
Decadal and multidecadal changes in the meridional overturning circulation may originate from either the subpolar North Atlantic or the Southern Hemisphere. New records of carbon and oxygen isotopes from an eastern Martinique Island (Lesser Antilles) coral reveal irregular, decadal, double-step events of low ∆C and enhanced vertical mixing, high δO and high δC values starting in 1885. Comparison of the new and published ∆C records indicates that the last event (1956-1969) coincides with a widespread, double-step ∆C low of South Atlantic origin from 32°N to 18°S, associated with a major slowdown of the Caribbean Current transport between 1963 and 1969. This event and the past Martinique ∆C lows are attributed to pulses of northward advection of low ∆C Sub-Antarctic Mode Waters into the tropical Atlantic. They are coeval with changes of the tropical freshwater budget and likely driven by meridional overturning circulation changes since ~1880.
PubMed: 38100584
DOI: 10.1126/sciadv.adi1687 -
Biomedical and Environmental Sciences :... Nov 2023To evaluate the effect of intense pulsed light (IPL) in the treatment of chronic hordeolum.
OBJECTIVE
To evaluate the effect of intense pulsed light (IPL) in the treatment of chronic hordeolum.
METHODS
Patients with chronic hordeolum who underwent IPL treatment were enrolled in this study. According to the severity of hordeolum, the patients were treated with IPL 3 to 5 times. Patients' satisfaction and visual analog scale scores for ocular discomfort symptoms before and after treatment were collected. The number, congestion, long diameter, short diameter and area of nodules were also recorded and measured. Finally, eyelid margin signs, meibum quality, meibomian gland expressibility, meibomian gland dropout, tear meniscus height, and corneal fluorescein staining were scored.
RESULTS
20 patients were enrolled in this study. The eyelid margins were congestive and swollen, with blunt rounding or irregularity. The meibum was cloudy or toothpaste-like. The meibomian gland expressibility, meibomian gland dropout and tear meniscus height were reduced. The cornea showed scattered fluorescein staining. After treatment, score of visual analog scale, congestion and size of nodules were significantly reduced. Eyelid margin signs, meibum quality, meibomian gland expressibility, tear meniscus height and corneal fluorescein staining scores were improved. Meibomian gland dropout had no significant change. No side effects occurred during treatment.
CONCLUSIONS
IPL is beneficial for the treatment of chronic hordeolum.
Topics: Humans; Hordeolum; Meibomian Glands; Tears; Fluoresceins
PubMed: 38098321
DOI: 10.3967/bes2023.131 -
PloS One 2023A mechanical device inspired by the rapid rotational motion of the pistol shrimp plunger has been developed to experimentally study the contraction/expansion dynamics of...
A mechanical device inspired by the rapid rotational motion of the pistol shrimp plunger has been developed to experimentally study the contraction/expansion dynamics of a gas bubble inside a confined liquid volume and in the vicinity of solid surfaces. The apparatus consists of a limb with a V-shaped end, which fits into a socket forming a cylindrical compression chamber. Air bubbles of different sizes and in different positions inside the chamber were seeded to study their shape evolution in liquids when subjected to pressure pulses induced by the limb closure. By changing the standoff and curvature parameters, as well as the closing power of the limb it was possible to control the dynamical behavior of the cavity. Four stages describing the dynamic behavior of the bubble were found: 1) A slight expansion-contraction stage accompanied by very weak volumetric oscillations. 2) First compression stage. The formation of gas and liquid micro-jets is observed when the vertical symmetry axis of the bubble is initially located outside of the chamber symmetry axis, on the other hand, when there is a coincidence between these axes, the bubble only contracts exhibiting non-spherical shapes, alternating between oblate and prolate spheroidal structures. 3) An expansion stage where the cavity reaches the walls of the chamber exhibiting irregular shapes on its surface. 4) Second compression stage. This process begins when the limb rebounds and stops sealing the chamber allowing a jet of liquid to enter from the fluid medium outside, inducing a very violent collapse accompanied by the emission of light. The proposed technique represents a novel alternative to study the dynamic evolution of bubbles near and on solid boundaries of various geometries. Other attractive features of the apparatus are its low manufacturing cost, simple design and compact size which makes it easily portable.
PubMed: 38096256
DOI: 10.1371/journal.pone.0293839 -
Expert Opinion on Drug Safety Dec 2023Long QT syndrome (LQTS) has been reported in older patients with advanced non-small cell lung cancer (NSCLC) following the use of osimertinib, the third-generation...
BACKGROUND
Long QT syndrome (LQTS) has been reported in older patients with advanced non-small cell lung cancer (NSCLC) following the use of osimertinib, the third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). However, there have not been analytic epidemiology studies on this topic. We aimed to compare the risk of LQTS between osimertinib and first/second-generation EGFR-TKIs in older patients with advanced NSCLC.
RESEARCH DESIGN AND METHODS
This retrospective observational study used the 2006-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare data and included older patients with advanced NSCLC who were treated with either osimertinib or first/second-generation EGFR-TKIs during 2007-2017. Inverse probability of treatment weighting (IPTW) was used to balance the two groups with propensity scores estimated based on the patients' socioeconomic and clinical characteristics. Crude incidence rate (IR) and adjusted hazard ratio (HR) of the primary outcome, incident LQTS, were estimated.
RESULTS
A total of 545 and 1,135 patients were included in the osimertinib and first/second-generation EGFR-TKI groups, which increased to 1,614 and 1,659, respectively, after IPTW. The osimertinib group had a higher IR of LQTS (2.62 per 100 person-years, 95% CI 2.03-3.38) compared to the first/second-generation EGFR-TKI group (1.33 per 100 person-years, 95% CI 0.92-1.92). After adjusting for covariates, the osimertinib group had a higher risk of LQTS than the first/second-generation EGFR-TKI group, with an HR of 1.94 (95% CI 1.23-3.08). The increased LQTS risk in the osimertinib group was even higher in females, whites and patients aged ≥ 75.
CONCLUSIONS
Given the elevated risk of LQTS associated with osimertinib user, close monitoring for cardiac rhythm irregularities of high-risk patients following initiation of EGFR-TKI is recommended.
PubMed: 38088244
DOI: 10.1080/14740338.2023.2294924 -
Journal of the American Heart... Dec 2023Excessive daytime sleepiness (EDS), experienced in 10% to 20% of the population, has been associated with cardiovascular disease and death. However, the condition is...
BACKGROUND
Excessive daytime sleepiness (EDS), experienced in 10% to 20% of the population, has been associated with cardiovascular disease and death. However, the condition is heterogeneous and is prevalent in individuals having short and long sleep duration. We sought to clarify the relationship between sleep duration subtypes of EDS with cardiovascular outcomes, accounting for these subtypes.
METHODS AND RESULTS
We defined 3 sleep duration subtypes of excessive daytime sleepiness: normal (6-9 hours), short (<6 hours), and long (>9 hours), and compared these with a nonsleepy, normal-sleep-duration reference group. We analyzed their associations with incident myocardial infarction (MI) and stroke using medical records of 355 901 UK Biobank participants and performed 2-sample Mendelian randomization for each outcome. Compared with healthy sleep, long-sleep EDS was associated with an 83% increased rate of MI (hazard ratio, 1.83 [95% CI, 1.21-2.77]) during 8.2-year median follow-up, adjusting for multiple health and sociodemographic factors. Mendelian randomization analysis provided supporting evidence of a causal role for a genetic long-sleep EDS subtype in MI (inverse-variance weighted β=1.995, =0.001). In contrast, we did not find evidence that other subtypes of EDS were associated with incident MI or any associations with stroke (>0.05).
CONCLUSIONS
Our study suggests the previous evidence linking EDS with increased cardiovascular disease risk may be primarily driven by the effect of its long-sleep subtype on higher risk of MI. Underlying mechanisms remain to be investigated but may involve sleep irregularity and circadian disruption, suggesting a need for novel interventions in this population.
Topics: Humans; Cardiovascular Diseases; Disorders of Excessive Somnolence; Sleep; Myocardial Infarction; Stroke
PubMed: 38084713
DOI: 10.1161/JAHA.122.030568 -
Annual International Conference of the... Jul 2023Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive method of brain stimulation that has been investigated for its use in the clinical treatment of a number...
Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive method of brain stimulation that has been investigated for its use in the clinical treatment of a number of different conditions. There has been little investigation into the stimulation current that is delivered and the effect on individual variability in response to tVNS.Seventeen participants underwent tVNS, and stimulation current was determined based on individual pain threshold. To investigate individual variability, brain dynamics were measured concurrently using magnetoencephalography (MEG) in response to two different stimulation protocols of tVNS. The first protocol consisted of a sequence of equally spaced short (1ms) stimulation pulses applied 24 times per second (24 Hz), and the second consisted of a sequence of 24 pulses per second spaced according to a 6 Hz pulse frequency modulation (PFM). Both stimulation sequences were delivered to the cymba concha in the left ear.The difference in brain responses to the two sequences was initially calculated using a one-sample t-test at the group level, based on z-scoring of the data at the individual level, and no statistically significant differences were observed. Further investigation of individual variability suggested that participants fell into two groups; one that responded more strongly to 24 Hz and one that responded more strongly to the irregular spacing of pulses in the PFM protocol.We tested whether the stimulation current that the participant received could predict how they would respond to the stimulation, but we did not observe any correlation. This supports the literature that suggests that selecting stimulation current based on individual pain threshold is a suitable procedure for tVNS, and higher stimulation intensities does not correspond to stronger brain response. Further investigation into individual variability in response to different frequencies and pulse spacing of tVNS should also be investigated further and may lead to the development of personalised stimulation protocols.Clinical relevance- The stimulation current at which tVNS is delivered does not appear to influence brain response to stimulation, and the value of stimulation current should be selected based on individual participant comfort.
Topics: Humans; Magnetoencephalography; Vagus Nerve Stimulation; Transcutaneous Electric Nerve Stimulation; Pain Threshold; Brain
PubMed: 38083575
DOI: 10.1109/EMBC40787.2023.10340991 -
Large-capacity AC superimposed DC power supply for the degradation evaluation of DC-link capacitors.The Review of Scientific Instruments Apr 2023The DC-link capacitor, whose operating voltage is a periodic irregular waveform, is a key device in the converter. A large-capacity DC/AC superimposed experimental power...
The DC-link capacitor, whose operating voltage is a periodic irregular waveform, is a key device in the converter. A large-capacity DC/AC superimposed experimental power supply above 100 kVA is an important piece of equipment that must be used in the aging research of DC-link capacitors. The irregular periodic operating voltage of the DC support capacitor is equivalent in the form of DC voltage superimposed with multiple harmonics based on the Fast Fourier transform analysis. The power supply is mainly divided into four parts: an AC module, a DC module, a protection module, and an isolation component. The composited harmonics are output by the IGBT (Insulated Gate Bipolar Transistor) inverter of the AC module. The soft start method is applied to the AC module in order to ensure the long-term reliable operation of the power supply. The kV-level high-voltage is output by four inverter units connected in series. The amplitude and phase control of harmonic decomposition is adopted, and the inverter is controlled by Sinusoidal Pulse Width Modulation. The output voltage of the power supply is close to the operating voltage of the capacitor. Based on the designed power supply, the degradation experiment was carried out. The temperature rise and aging characteristics of DC-link capacitors under different AC/DC ratios were studied.
PubMed: 38081234
DOI: 10.1063/5.0138117 -
ELife Dec 2023Sudden cardiac death (SCD) from ventricular tachycardia/fibrillation (VT/VF) is a leading cause of death, but current therapies are limited. Despite extensive research... (Randomized Controlled Trial)
Randomized Controlled Trial
Sudden cardiac death (SCD) from ventricular tachycardia/fibrillation (VT/VF) is a leading cause of death, but current therapies are limited. Despite extensive research on drugs targeting sarcolemmal ion channels, none have proven sufficiently effective for preventing SCD. Sarcoplasmic ryanodine receptor 2 (RyR2) Ca release channels, the downstream effectors of sarcolemmal ion channels, are underexplored in this context. Recent evidence implicates reactive oxygen species (ROS)-mediated oxidation and hyperactivity of RyR2s in the pathophysiology of SCD. We tested the hypothesis that RyR2 inhibition of failing arrhythmogenic hearts reduces sarcoplasmic Ca leak and repolarization lability, mitigates VT/VF/SCD and improves contractile function. We used a guinea pig model that replicates key clinical aspects of human nonischemic HF, such as a prolonged QT interval, a high prevalence of spontaneous arrhythmic SCD, and profound Ca leak via a hyperactive RyR2. HF animals were randomized to receive dantrolene (DS) or placebo in early or chronic HF. We assessed the incidence of VT/VF and SCD (primary outcome), ECG heart rate and QT variability, echocardiographic left ventricular (LV) structure and function, immunohistochemical LV fibrosis, and sarcoplasmic RyR2 oxidation. DS treatment prevented VT/VF and SCD by decreasing dispersion of repolarization and ventricular arrhythmias. Compared to placebo, DS lowered resting heart rate, preserved chronotropic competency during transient β-adrenergic challenge, and improved heart rate variability and cardiac function. Inhibition of RyR2 hyperactivity with dantrolene mitigates the vicious cycle of sarcoplasmic Ca leak-induced increases in diastolic Ca and ROS-mediated RyR2 oxidation, thereby reducing repolarization lability and protecting against VT/VF/SCD. Moreover, the consequent increase in sarcoplasmic Ca load improves contractile function. These potentially life-saving effects of RyR2 inhibition warrant further investigation, such as clinical studies of repurposing dantrolene as a potential new therapy for heart failure and/or SCD.
Topics: Humans; Animals; Guinea Pigs; Ryanodine Receptor Calcium Release Channel; Dantrolene; Reactive Oxygen Species; Heart Failure; Arrhythmias, Cardiac; Tachycardia, Ventricular; Death, Sudden, Cardiac; Calcium; Myocytes, Cardiac
PubMed: 38078905
DOI: 10.7554/eLife.88638 -
The Permanente Journal Mar 2024Atrial fibrillation (AF) is an arrhythmia characterized by disorganized atrial activity with an associated unevenly irregular ventricular response on an...
Atrial fibrillation (AF) is an arrhythmia characterized by disorganized atrial activity with an associated unevenly irregular ventricular response on an electrocardiogram. It is the most common sustained arrhythmia, with a lifetime risk of 25% in patients older than 40 years old. The incidence of AF increases with age and is associated with an increased risk for heart failure, stroke, adverse cardiac events, and dementia. The 2 main aims of AF treatment include anticoagulation for thromboembolism prophylaxis as well as rate vs rhythm control. The focus of this article will be on the treatment strategies in managing AF. Rate control refers to the use of atrioventricular nodal blocking medications, including beta blockers and calcium channel blockers, to maintain a goal heart rate. Rhythm control, on the other hand, refers to a treatment strategy focused on the use of antiarrhythmic drugs (AAD), cardioversion, and ablation to restore and to maintain a patient in sinus rhythm. Currently, the ideal treatment strategy remains greatly debated. Thus, we hope to compare the risks and benefits of rate to rhythm control to highlight how patients with AF are managed here at Kaiser Permanente Northern California.
Topics: Humans; Adult; Atrial Fibrillation; Anti-Arrhythmia Agents; Heart Rate; Electric Countershock; Heart Failure
PubMed: 38073307
DOI: 10.7812/TPP/23.151