Descriptions of Etiology, Clinical Course, and Prognosis of Patients Presenting with Pericardial Effusion.

Pericardial effusion (PE) presentation varies from an incidental finding to a life-threatening situation; thus, its etiology and clinical course remain unknown. The aim of the present study was to retrospectively investigate these factors.We analyzed 171 patients (0.4%) who presented with PE among 34,873 patients who underwent echocardiography between 2011 and 2021 at our hospital. Clinical and prognostic information was retrieved from electronic medical records. The primary endpoints were all-cause death, hospitalization due to heart failure (HF), and other cardiovascular events such as cardiovascular death, acute coronary syndrome, elective percutaneous coronary intervention, and stroke.The etiologies of PE were as follows: idiopathic (32%), HF-related (18%), iatrogenic (11%), cardiac surgery-related (10%), radiation therapy-related (9%), malignancy (8%), pericarditis/myocarditis (8%), myocardial infarction-related (2%), and acute aortic dissection (2%). Patients with idiopathic/HF etiology were more likely to be older than the others.During a mean follow-up period of 2.5 years, all-cause death occurred in 21 patients (12.3%), cardiovascular events in 10 patients (5.8%), and hospitalization for HF in 24 patients (14.0%). All-cause death was frequently observed in patients with malignancy (44% per person-year). Cardiovascular events were mostly observed in patients with radiation therapy-related and malignancy (8.6% and 7.3% per person-year, respectively).The annual incidence of hospitalization for HF was the highest in patients with HF-related (25.1% per person-year), followed by radiation therapy-related (10.4% per person-year).This retrospective study is the first, to the best of our knowledge, to reveal the contemporary prevalence of PE, its cause, and outcome in patients who visited a cardiovascular hospital in an urban area of Japan.

Interfacial Selective Study on the Gelation Behavior of Aqueous Methylcellulose Solution via a Quartz Crystal Microbalance.

It is important to understand the interfacial structure and physical properties of a polymer material to improve its function. In this study, we used a quartz crystal microbalance (QCM) and neutron reflectivity (NR) measurements to evaluate the viscoelasticity and structure of an aqueous methylcellulose solution near the gold interface. The apparent shear modulus, which was calculated from the complex frequency, was used to assess gelation behavior. The apparent shear modulus determined via the QCM suggested high-frequency rheological properties that reflected the relaxation of skeletal stretching and rotational motion of polymer segments, as well as cooperative motion of the various functional groups. The gelation temperature was found to be lowered at the interface in comparison with that of the bulk. It is suggested that the QCM can evaluate the shear modulus accompanying the gelation near the interface. The interfacial segregation on the gold substrate caused by the surface free energy and long-range van der Waals interaction was observed from NR measurements.

Clinical Importance of the LDL-C/Apolipoprotein B Ratio for Neointimal Formation after Everolimus-Eluting Stent Implantations.

AIMS: Smaller low-density lipoprotein (LDL) particle size has been suggested to result in the development of endothelial dysfunction, atherosclerosis, and in-stent restenosis (ISR); however, little is known regarding the impact of the LDL particle size on the neointima formation leading to ISR after everolimus-eluting stent (EES) implantation. METHODS: In this study, we have included 100 patients to examine the relationship between an LDL-C/apolipoprotein B (Apo B) ≤ 1.2, reportedly representing the LDL particle size, and the neointimal characteristics using optical coherence tomography (OCT) and coronary angioscopy (CAS) during the follow-up coronary angiography (CAG) period (8.8±2.5 months) after EES implantation. We divided them into two groups: LDL-C/Apo B ≤ 1.2 group (low LDL-C/Apo B group, n=53) and LDL-C/Apo B ＞1.2 group (high LDL-C/Apo B group, n=47). RESULTS: The low LDL-C/Apo B group had a significantly larger neointimal volume (12.8±5.3 vs. 10.3±4.9 mm3, p=0.021) and lower incidence of a neointimal homogeneous pattern (71 vs. 89 %), higher incidence of a neointimal heterogeneous pattern (25 vs. 9 %) (p=0.006) and higher prevalence of macrophage accumulation (9 vs. 2 %) (p=0.030) as assessed via OCT, and, as per the CAS findings, a higher prevalence of yellow grade ≥ 2 (grade 2; adjusted residual: 2.94, grade 3; adjusted residual: 2.00, p=0.017) than the high LDL-C/Apo B group. CONCLUSIONS: A low LDL-C/Apo B ratio was found to be strongly associated with neointimal proliferation and neointimal instability evidenced chronically by OCT and CAS. An LDL-C/Apo B ≤ 1.2 will be of aid in terms of identifying high-risk patients after EES implantation.

Application of precise neutron focusing mirrors for neutron reflectometry: latest results and future prospects.

Neutron reflectometry (NR) is a powerful tool for providing insight into the evolution of interfacial structures, for example via operando measurements for electrode-electrolyte interfaces, with a spatial resolution of nanometres. The time resolution of NR, which ranges from seconds to minutes depending on the reflection intensity, unfortunately remains low, particularly for small samples made of state-of-the-art materials even with the latest neutron reflectometers. To overcome this problem, a large-area focusing supermirror manufactured with ultra-precision machining has been employed to enhance the neutron flux at the sample, and a gain of approximately 100% in the neutron flux was achieved. Using this mirror, a reflectivity measurement was performed on a thin cathode film on an SrTiO3 substrate in contact with an electrolyte with a small area of 15 × 15 mm. The reflectivity data obtained with the focusing mirror were consistent with those without the mirror, but the acquisition time was shortened to half that of the original, which is an important milestone for rapid measurements with a limited reciprocal space. Furthermore, a method for further upgrades that will reveal the structural evolution with a wide reciprocal space is proposed, by applying this mirror for multi-incident-angle neutron reflectometry.

Effective Pacing Intervention by Closed-loop Stimulation Using a Coronary Vein Lead in a Post-tricuspid Valve Replacement Patient.

To avoid the negative effects associated with pacing, pacemakers are designed to achieve a pacing cadence as close to physiological pacing as possible. In closed-loop stimulation (CLS; a type of rate-responsive functionality used in pacemakers), the changes in impedance (which correlates with the contractility of the myocardium around the lead tip electrode) are tracked, and the paced heart rate is adjusted accordingly. We herein report a case in which we implanted a pacemaker in a post-tricuspid valve replacement patient. A ventricular lead positioned in the coronary vein exhibited good CLS functionality, and the patient's dizziness and heart failure improved.

Association of patient satisfaction with direct oral anticoagulants and the clinical outcomes: Findings from the SAKURA AF registry.

BACKGROUND: The burden or benefit of anticoagulation treatment affects patient satisfaction, which may in turn affect the adherence to the treatment and subsequent outcomes. Thus, we hypothesized that the patient satisfaction with direct oral anticoagulants (DOACs) may influence the clinical outcome in patients with atrial fibrillation (AF). METHODS AND RESULTS: We investigated the clinical outcomes among 719 DOAC users (age 71.9 ± 9.1 years, 184 females, and 449 persistent AF) enrolled in the SAKURA AF Registry who completed a satisfaction questionnaire with anticoagulation therapy by means of the Anti-Clot Treatment Scale (ACTS), which included 12-item burden and 3-item benefit scales. During a 41.8-month-follow-up, a stroke/systemic embolism (SE) occurred in 27 patients (3.8%) and major bleeding events in 25 (3.5%). A univariate Cox regression analysis revealed that an older age, persistent AF, higher CHA2DS2-VASc score, no history of AF ablation, lower creatinine clearance, and lower ACTS benefit scores were significantly associated with an increased risk of a stroke/SE, but not with major bleeding events. A low benefit score remained an independent predictor of a stroke/SE even after a multivariate adjustment. The ACTS burden scores were not associated with any clinical events. CONCLUSIONS: We found a strong association between a low benefit satisfaction and increased stroke risk. We should follow patients carefully to educate them on treatment importance for patients unsatisfied with the benefits of DOACs for stroke prevention.

Elliptic neutron-focusing supermirror for illuminating small samples in neutron reflectometry.

This paper details the development of a precise assembly of two supermirrors for neutron-focusing, designed for installation in neutron reflectometer SOFIA at BL16 in J-PARC MLF to intensify the illumination for small samples. The supermirrors are sputtered on two metal substrates, whose surfaces are coated with amorphous Ni-P plating, and are figured by diamond cutting and polished to subnanometer roughness. Special care is taken while polishing the substrates to reduce waviness and surface roughness for achieving a sharp focusing spot and uniform neutron reflectivity. The supermirror could converge the neutrons into a focal spot with a width of 0.13 mm in the full width at half maximum.

Development of precision elliptic neutron-focusing supermirror.

This paper details methods for the precision design and fabrication of neutron-focusing supermirrors, based on electroless nickel plating. We fabricated an elliptic mirror for neutron reflectometry, which is our second mirror improved from the first. The mirror is a 550-millimeter-long segmented mirror assembled using kinematic couplings, with each segment figured by diamond cutting, polished using colloidal silica, and supermirror coated through ion-beam sputtering. The mirror was evaluated with neutron beams, and the reflectivity was found to be 68-90% at a critical angle. The focusing width was 0.17 mm at the full width at half maximum.

Structure and Mechanical Properties of Polybutadiene Thin Films Bound to Surface-Modified Carbon Interface.

The structure and mechanical properties of polybutadiene (PB) films on bare and surface-modified carbon films were examined. There was an interfacial layer of PB near the carbon layer whose density was higher (lower) than that of the bulk material on the hydrophobic (hydrophilic) carbon surface. To glean information about the structure and mechanical properties of PB at the carbon interface, a residual layer (RL) adhering to the carbon surface, which was considered to be a model of "bound rubber layer", was obtained by rinsing the PB film with toluene. The density and thickness of the RLs were identical to those of the interfacial layer of the PB film. In accordance with the change in the density, normal stress of the RLs evaluated by atomic force microscopy was also dependent on the surface free energy: the RLs on the hydrophobic carbon were hard like glass, whereas those on the hydrophilic carbon were soft like rubber. Similarly, the wear test revealed that the RLs on the hydrophilic carbon could be peeled off by scratching under a certain stress, whereas the RLs on the hydrophobic carbons were resistant to scratching.

Load-Induced Frictional Transition at a Well-Defined Alkane Loop Surface.

Self-assembled monolayers (SAMs) have attracted considerable attention as a tool to confer desirable properties on material surfaces. So far, molecules used for the SAM formation are generally limited to linear ones and thus chain ends dominate the surface properties. In this study, we have successfully demonstrated unique frictional properties of a SAM composed of alkane loops from cyclic alkanedisulfide on a gold substrate, where both sulfurs are bound to gold. The frictional response was proportional to the load. However, once the load went beyond a threshold value, the frictional response became more dominant. Such a frictional transition was reversible and repeatable and was not discerned for a corresponding SAM composed of n-alkyl chains. The load-induced change in the frictional response from the alkane loops could be associated with the conformational change of the alkane loops. The present results differ from most studies, in which the surface properties are designed on the basis of functional chain end groups.

Hierarchical spatial heterogeneity in liquid crystals composed of graphene oxides.

Graphene oxide (GO) is a class of two-dimensional materials with a thickness of about 1 nm and a broad distribution of lateral dimension commonly approaching several micrometers. A dispersion of GOs in water often forms a liquid crystal, which is expected to be a promising precursor for the fabrication of carbon-based materials with well-ordered structures. To accelerate the application of GO-based liquid crystals, their structures and physical properties at various sizes must be well understood. To that end, we examined the local rheological properties of GO-based liquid crystals in the nematic phase using a particle tracking technique, where local properties can be accessed by observing the thermal motion of embedded probe particles. Particle diffusion was spatially heterogeneous, and depended on the size of the particles. Such a size-dependent heterogeneity can be associated with a hierarchical local environment, which is time-dependent for this system. The anisotropic particle diffusion originated from particles trapped in between the GO layers and in isotropic-like regions. The aggregation states of the GO dispersion composed of nematic and isotropic-like regions were observed using confocal laser scanning microscopy.

Nonsolvents-induced swelling of poly(methyl methacrylate) nanoparticles.

Polymer nanoparticles have been used in a wide variety of applications. In most of these applications, they are generally dispersed in a non-solvent. However, the effect of the non-solvent on the structure, physical properties and function of the nanoparticles has not yet ever taken into account. In this study, monodispersed poly(methyl methacrylate) (PMMA) nanoparticles were prepared by a surfactant-free emulsion polymerization. The PMMA nanoparticles were dispersed in water and in methanol, both typical non-solvents for PMMA, so that we could discuss the effect of the non-solvent on the nanoparticles. Dynamic light scattering measurements revealed that the hydrodynamic radius of the PMMA nanoparticles in methanol was larger than the same PMMA dispersed in water. Their DLS values were also larger than the radius of the nanoparticles measured by atomic force microscopy. When pyrene was dispersed in methanol with the PMMA nanoparticles, it was incorporated into the nanoparticles. These results clearly indicate that non-solvent molecules can be sorbed into polymer nanoparticles because the area of the interface, where polymer segments might be dissolved into liquid phases, as the total volume is quite larger for such nanoparticles. Therefore, based on our findings, it can be arguably established that the present assumption for a polymer not to be swollen in its non-solvent is not necessarily true.

Design of a dynamic polymer interface for chiral discrimination.

Enantioselective wetting of a chiral polymer film was demonstrated. The contact angle of chiral liquids on the film was strongly dependent on their chirality although their physical properties including surface tension were identical. Such wetting behavior resulted from the enantioselective surface reorganization involving local conformational change of the polymer chains at the liquid interface. The concept of "dynamic interface for chiral discrimination" has possible potential for the development of materials capable of chiral sensing, optical resolution, and asymmetric synthesis.

Optical tweezers with fluorescence detection for temperature-dependent microrheological measurements.

We introduce a setup of optical tweezers, capable of carrying out temperature-dependent rheological measurements of soft materials. In our setup, the particle displacement is detected by imaging a bright spot due to fluorescence emitted from a dye-labeled particle against a dark background onto a quadrant photodiode. This setup has a relatively wide space around the sample that allows us to further accessorize the optical tweezers by a temperature control unit. The applicability of the setup was examined on the basis of the rheological measurements using a typical viscoelastic system, namely a worm-like micelle solution. The temperature and frequency dependences of the local viscoelastic functions of the worm-like micelle solution obtained by this setup were in good accordance with those obtained by a conventional oscillatory rheometer, confirming the capability of the optical tweezers as a tool for the local rheological measurements of soft materials. Since the optical tweezers measurements only require a tiny amount of sample (~40 µL), the rheological measurements using our setup should be useful for soft materials of which the available amount is limited.

Spatial heterogeneity in a lyotropic liquid crystal with hexagonal phase.

Non-ionic surfactant hexaethylene glycol, C(12)E(6), in water self-assembles into various kinds of mesophases by varying the surfactant concentration. A spatial heterogeneity was discussed on the basis of the diffusion of probe particles dispersed in the C(12)E(6)-water solution. Interestingly, at 50 wt% C(12)E(6) where the hexagonal structure was formed, two kinds of motion of probe particles were observed: some particles normally diffused while others were restricted, indicating the existence of a heterogeneity in the physical properties. Such heterogeneity can be explained in terms of heterogeneous structures composed of hexagonal domains with isotropic-like regions.

Optimum pain relief with continuous epidural infusion of local anesthetics shortens the duration of zoster-associated pain.

OBJECTIVE: To investigate effects of continuous epidural infusion (CEI) of 0.5% bupivacaine added to intermittent epidural boluses (IEB) on the duration of zoster-associated pain (ZAP), as compared with continuous infusion of normal saline placebo added to IEB. DESIGN: A prospective, double-blind, randomized, placebo-controlled study. SETTING: A university hospital and an affiliated clinic in Japan from 1996 through 1999. PATIENTS: 56 immunocompetent herpes zoster (HZ) patients, 50 years or older, within 10 days of rash onset and with severe pain and eruption. INTERVENTIONS: Patients were hospitalized and randomly allocated into 2 groups. CEI group given CEI of 0.5% bupivacaine (0.5-1.0 mL/h) plus IEB of 0.5% bupivacaine 4 times daily (n = 29). IEB group given normal saline infusion plus IEB of 0.5% bupivacaine 4 times daily (n = 27). All patients received oral acyclovir 800 mg, 5 times daily, for 7 days. OUTCOME MEASURES: The number of days required for complete cessation of ZAP and the proportion of subjects with allodynia beyond 30 days. RESULTS: The median time to cessation of ZAP was significantly shorter in the CEI group than in the IEB group (29 days vs. 40 days, P = 0.002). The number of patients whose allodynia persisted beyond 30 days of treatment was significantly lower in the CEI group than in the IEB group (10% vs. 37%, P = 0.027). CONCLUSIONS: CEI of 0.5% bupivacaine plus IEB was associated with a shorter duration of ZAP and fewer patients with allodynia beyond 30 days, compared with IEB plus normal saline infusion. Patients at high risk for developing postherpetic neuralgia (PHN) can be managed with intensive therapies at the early stage of disease, such as CEI, which maintains effective analgesia and may reduce the burden of PHN.

Biphasic vasomotor reflex responses of the hand skin following intradermal injection of melittin into the forearm skin.

Melittin is the main toxin of honeybee venom. Previously, we have reported that intradermal injection of melittin into the volar aspect of forearm in humans produces a temporary pain and a subsequent sustained increase in the skin temperature due to axon reflex. To clarify the interaction between nociceptive inputs and vascular changes, we studied the influence of noxious stimulation by intradermal melittin on the vasomotor control of the distal extremities in human volunteers. Temperature changes of the bilateral palmar surface were recorded by means of a computer-assisted infrared thermography. Unexpectedly, we found a biphasic response of skin temperature. The skin temperature of both fingers and hands decreased immediately after the melittin injection and then increased well above the control level, prior to the injection. There was a considerable individual variation in the baseline skin temperature, prior to melittin. The skin temperature in a finger/hand with lower preinjection value increased more markedly in the second phase. Consequently, the individual variation in the peak temperature of the second phase was less pronounced. The initial decrease was interpreted as sympathetic vasoconstrictor reflex induced by noxious stimulation and the later increase as release of sympathetic vasomotor tone.

Severity of skin lesions of herpes zoster at the worst phase rather than age and involved region most influences the duration of acute herpetic pain.

Duration of acute herpetic pain (AHP) in 1431 patients for whom treatment was begun within 14 days after the onset of herpes zoster (HZ) was analyzed with respect to age, involved region, and severity of skin lesions. All patients were treated with repeated sympathetic nerve blocks until their pain was almost nil. Severity of the skin lesions at the worst phase was defined as mild when they covered less than one-quarter of the primary dermatome, as severe when they covered more than three-quarters of the primary dermatome, and moderate if they were between mild and severe. Without taking into account the severity of skin lesions, the duration of AHP for those aged 60 years or over and for those with trigeminal involvement was significantly longer than for patients aged under 40 years (P < 0.01 and P < 0.001) and for patients with thoracic (P < 0.001) and lumbosacral (P < 0.01) involvement, respectively. However, duration of AHP was significantly longer with increase in the severity of skin lesions in all age groups (the mild group versus the moderate group, P < 0.01 and P < 0.001; the moderate group versus the severe group, P < 0.01 and P < 0.001). The mean duration of AHP for patients aged 60 years or over with mild skin lesions ranged from 17.4 to 22.9 days, while that for patients aged 30-59 years with severe skin lesions ranged from 37.2 to 50.1 days. In addition, duration of AHP was significantly longer with increase in the severity of skin lesions in all regions (the mild group versus the moderate group, P < 0.01 and P < 0.001; the moderate group versus the severe group, P < 0.05 and P < 0.001). The mean duration of AHP for those with trigeminal involvement with mild skin lesions was 19.5 days, while the range was from 51.3 to 55.0 days for patients with severe skin lesions involving regions other than the trigeminal area. The frequency of severe skin lesions was significantly higher (P < 0.001) in patients aged 60 years or over and in those with trigeminal involvement. Multiple stepwise regression analysis revealed that the most important factors influencing the duration of AHP were the severity of skin lesions of HZ at the worst phase (r = 0.412), age (r = 0.277) and the involved region (r = -0.101). Thus, AHP in the elderly and in cases of trigeminal involvement is longer because of higher frequencies of severe HZ in the elderly and in trigeminal involvement rather than "being aged' and "trigeminal involvement' itself. We propose that one needs to analyze the results of treatment of AHP with respect to the severity of skin lesions at the worst phase.