Medical student medium-term skill retention following cardiac point-of-care ultrasound training based on the American Society of Echocardiography curriculum framework.

BACKGROUND: No studies have demonstrated medium- or long-term skill retention of cardiac point-of-care ultrasound (POCUS) curriculum for medical student. Based on the American Society of Echocardiography (ASE) curriculum framework, we developed a blended-learning cardiac POCUS curriculum with competency evaluation. The objective of this study was to investigate the curriculum impact on image acquisition skill retention 8 weeks after initial training. METHODS: This study was a prospective, pre-post education intervention study for first- and second-year medical students, with blinded outcome assessment. The curriculum included a pre-training ASE online module and healthy volunteer hands-on training to obtain 5 views: parasternal long-axis (PLAX), parasternal short-axis (PSAX), apical 4-chamber (A4C), subcostal 4-chamber (S4C), and subcostal inferior vena cava (SIVC) views. Students took 5-view image acquisition skill tests at pre-, immediate post-, and 8-week post-training, using a healthy volunteer. Three blinded assessors rated the image quality using a validated 10-point maximum scoring system. Students used a hand-held ultrasound probe (Butterfly iQ). RESULTS: Fifty-four students completed hands-on training, and pre- and immediate post-training skill tests. Twenty-seven students completed 8-week post-training skill tests. Skill test score improvement between pre- and 8-week post-training was 2.11 points (95% CI, 1.22-3.00; effect size, 1.13). CONCLUSION: The cardiac POCUS curriculum demonstrated medium-term skill retention. The curriculum was sufficient for S4C and SIVC skill retention, but inadequate for PLAX, PSAX, and A4C. Therefore, instructional design modifications or re-training for PLAX, PSAX, and A4C are needed to make the curriculum more effective for clinically relevant skill retention.

Synthesis of a Crystalline and Transparent Aerogel Composed of Ni-Al Layered Double Hydroxide Nanoparticles through Crystallization from Amorphous Hydrogel.

Enormous efforts have been devoted to the development of crystalline aerogels toward heterogeneous catalysis, energy storage, ion/molecular absorption, and luminescence. However, properties of aerogels are not fully exploited due to their low content of functional moieties embedded in their solid networks, low crystallinity, and limited chemical compositions. Herein, we develop a one-pot approach based on crystallization from amorphous metal hydroxides modified with a ß-diketone ligand, toward crystalline transition-metal hydroxide aerogels. Synthesis of monolithic and crystalline aerogels of layered double hydroxide (LDH) was performed in a Ni-Al system starting from aqueous ethanol solutions of NiCl2·6H2O and AlCl3·6H2O with acetylacetone (acac) as an organic ligand. Propylene oxide (PO) as an alkalization reagent was added into precursory solutions to yield monolithic wet gels. The successive pH increase induces the formation of a three-dimensional (3-D) solid framework composed of amorphous Al(OH)3. Then, amphoteric Al(OH)3 undergoes crystallization into Ni-Al LDH via an acetylacetone-driven dissolution-crystallization of metal hydroxides without destroying the preformed 3-D solid framework. The process allows us to obtain crystalline aerogel monoliths with high porosity and high transparency after supercritical CO2 drying of wet gels. The present scheme can be expected to synthesize functionalized aerogel composed of crystalline transition-metal oxide/hydroxide nanobuilding blocks (NBBs).

Network topology for the formation of solvated electrons in binary CaO-Al2O3 composition glasses.

Glass formation in the CaO-Al2O3 system represents an important phenomenon because it does not contain typical network-forming cations. We have produced structural models of CaO-Al2O3 glasses using combined density functional theory-reverse Monte Carlo simulations and obtained structures that reproduce experiments (X-ray and neutron diffraction, extended X-ray absorption fine structure) and result in cohesive energies close to the crystalline ground states. The O-Ca and O-Al coordination numbers are similar in the eutectic 64 mol % CaO (64CaO) glass [comparable to 12CaO·7Al2O3 (C12A7)], and the glass structure comprises a topologically disordered cage network with large-sized rings. This topologically disordered network is the signature of the high glass-forming ability of 64CaO glass and high viscosity in the melt. Analysis of the electronic structure reveals that the atomic charges for Al are comparable to those for Ca, and the bond strength of Al-O is stronger than that of Ca-O, indicating that oxygen is more weakly bound by cations in CaO-rich glass. The analysis shows that the lowest unoccupied molecular orbitals occurs in cavity sites, suggesting that the C12A7 electride glass [Kim SW, Shimoyama T, Hosono H (2011) Science 333(6038):71-74] synthesized from a strongly reduced high-temperature melt can host solvated electrons and bipolarons. Calculations of 64CaO glass structures with few subtracted oxygen atoms (additional electrons) confirm this observation. The comparable atomic charges and coordination of the cations promote more efficient elemental mixing, and this is the origin of the extended cage structure and hosted solvated (trapped) electrons in the C12A7 glass.

Efficacy and Safety Evaluation of Tolvaptan on Management of Fluid Balance after Cardiovascular Surgery Using Cardiopulmonary Bypass.

Background: Tolvaptan is an orally administered selective vasopressin 2 receptor antagonist that promotes aquaresis. This study aimed to evaluate the efficacy and safety of tolvaptan on management of systemic fluid balance after cardiovascular surgery using cardiopulmonary bypass. . Methods: Sixty-four patients who underwent cardiovascular surgery using cardiopulmonary bypass in our hospital were enrolled for this prospective, randomized study. These patients were divided into three groups: tolvaptan 15 mg+furosemide 20 mg (TH group), tolvaptan 7.5 mg+furosemide 20 mg (TI group), and furosemide 40 mg+spironolactone 50 mg (C group). The endpoint was safety management of systemic fluid balance using tolvaptan without renal dysfunction and electrolyte imbalance. Results: The mean daily urine output in the TH and TL groups (2656±767 and 2505 ±684 mL) was significantly higher than that in the C group (1956±494 mL, TH vs C: p<0.01 and TL vs C: p=0.03). The lowest serum sodium level during medication in the TH group (139.3 ±2.3 mEq/L) was significantly higher than that in the C group (137.1±2.9 mEq/L, p=0.03) The lowest serum osmolality during medication in the TH group was significantly higher than that in the C group (284.8 ±4.3 vs 279.5± 6.3 mOsm/kg, p<0.01). None had critical hypernatremia, hyperosm6lality, or renal dysfunction in any. of the groups. Conclusions: Tolvaptan exerts, a strong diuretic effect compared with conventional diuretics (furosemide and spironolactone) during the postoperative period after an operation using cardiopulmonary bypass without adverse effects on electrolyte balance and renal function.

X-ray phase-contrast computed tomography visualizes the microstructure and degradation profile of implanted biodegradable scaffolds after spinal cord injury.

Tissue engineering strategies for spinal cord repair are a primary focus of translational medicine after spinal cord injury (SCI). Many tissue engineering strategies employ three-dimensional scaffolds, which are made of biodegradable materials and have microstructure incorporated with viable cells and bioactive molecules to promote new tissue generation and functional recovery after SCI. It is therefore important to develop an imaging system that visualizes both the microstructure of three-dimensional scaffolds and their degradation process after SCI. Here, X-ray phase-contrast computed tomography imaging based on the Talbot grating interferometer is described and it is shown how it can visualize the polyglycolic acid scaffold, including its microfibres, after implantation into the injured spinal cord. Furthermore, X-ray phase-contrast computed tomography images revealed that degradation occurred from the end to the centre of the braided scaffold in the 28 days after implantation into the injured spinal cord. The present report provides the first demonstration of an imaging technique that visualizes both the microstructure and degradation of biodegradable scaffolds in SCI research. X-ray phase-contrast imaging based on the Talbot grating interferometer is a versatile technique that can be used for a broad range of preclinical applications in tissue engineering strategies.

[Surgical treatment for pseudoaneurysm of the sinus of valsalva ruptured into the right atrium after mycotic right coronary artery aneurysm repair;report of a case].

A 67-year-old man was admitted to our hospital by ambulance after syncope due to complete A-V block. He had received surgical treatment for mycotic aneurysm of the right coronary artery 3 months before, with patch plasty of the right sinus of Valsalva and bypass grafting to the right coronary artery (RCA) as well as the left anterior descending branch. Computed tomography revealed pseudoaneurysm of the right Valsalva sinus of about 8 cm in diameter and a shunt flow to the right atrium. The previous bypass graft to RCA had been occluded due to compression by the aneurysm. As he was in a shock state, emergency operation was performed. Cardiopulmonary bypass was first established, and after the rectal temperature reached to 26 degrees centigrade, the chest was opened. The pseudoaneurysm burst out when the sternum was re-opened. Under circulatory arrest, the ascending aorta was clamped, and then the circulation was resumed. The previous bovine pericardium patch repairing the Valsalva sinus was detached due to infection, and mural thrombus and pus were observed in the aneurysm. At the bottom of the aneurysm, a fistula connected to the right atrium was found. Debridement around the aneurysm was performed as much as possible. The defect of the Valsalva sinus was repaired with a Dacron patch immersed in gentian violet. The postoperative course was uneventful without any recurrence of infection.

Synthesis of Hydrophilic Poly(vinylpyrrolidone)/CuS Free-Standing Thin Films Exhibiting Photothermal Conversion.

Free-standing films without the need for any support materials attract attention because of their excellent flexibility in use and ability to be transferred to various substrates. However, free-standing films containing large amounts of inorganic crystalline particles are hard to achieve due to their low strength. In this study, we found the possibility of preparing a free-standing composite film of CuS/polyvinylpyrrolidone (PVP) at a large loading of CuS (>50%) from a concentrated colloidal dispersion of CuS nanoparticles modified with PVP. Despite the large amount of inorganic crystals contained in the free-standing film, the film was strong enough to be handled without any support materials. As a proof-of-concept application of the free-standing film, a solar water evaporation experiment was performed. The CuS/PVP free-standing film exhibited photothermal conversion under light illumination to generate heat and accelerate water evaporation, achieving an evaporation rate of 4.35 kg·m-2 h-1 and an evaporation efficiency of 96.3% at a power density of 3 suns. In addition, thanks to the free-standing feature, one side of the CuS/PVP film could be hydrophobized with polydimethylsiloxane to form a Janus thin film, allowing for floating on the water surface. As a result, effective water evaporation was achieved because of the selective evaporation of water from the air/water interface.

[Axillo-axillary bypass for coronary-subclavian steal syndrome].

We describe a case of coronary-subclavian steal syndrome in a 77-year-old man who presented with progressive coronary ischemia 8 years after coronary artery bypass grafting with an in-situ left internal thoracic artery graft. Coronary and left subclavian artery angiogram revealed completely patent internal thoracic artery graft and 90% stenosis in the proximal left subclavian artery. We performed axilloaxillary artery bypass using expanded polytetrafluoroethylene (ePTFE)[8 mm] graft. No coronary ischemia was noted postoperatively. Axillo-axillary artery bypass grafting was effective for coronary subclavian steal syndrome.

Efficacy of landiolol hydrochloride for prevention of atrial fibrillation after heart valve surgery.

The goal of this prospective study was to examine the effects of landiolol hydrochloride on prevention of atrial fibrillation and on hemodynamics in the acute postoperative phase after heart valve surgery. The subjects were 60 patients who underwent valve surgery at our hospital from April 2008 to July 2010. The patients were randomly divided into two groups: the landiolol group (30 patients) and the control (no landiolol) group (30 patients). In the landiolol group, continuous intravenous landiolol was initiated immediately on admission to the intensive care unit at a dose of 10 µg/kg/ minute. Occurrence of atrial fibrillation was compared between the groups over an observation period of 72 hours after surgery. Atrial fibrillation occurred in 6 patients (20%) in the landiolol group and 16 (53.3%) in the control group during the observation period. Landiolol hydrochloride significantly reduced the occurrence of atrial fibrillation in the acute postoperative phase after heart valve surgery. Heart rate was significantly decreased by landiolol, but aggravation of hemodynamics was not observed. These results suggest that landiolol is a useful drug for prevention of atrial fibrillation after valve surgery.

[Hybrid repair of thoracoabdominal aortic aneurysm in high-risk patients using a quadrifurcated graft].

Surgical treatment for thoracoabdominal aortic aneurysm is still challenging and is associated with a high risk of paraplegia. Hybrid repair with stent graft insertion for the thoracoabdominal aorta excluding the branches of the lumbar and visceral arteries and bypass grafting to the visceral branches has been introduced as a less invasive treatment that reduces the risk of paraplegia. For hybrid repair, it is important to have appropriate management of the revascularized grafts to the 4 visceral arteries with sufficient inflow. We have recently adopted a knitted quadrifurcated graft applied inversely from the abdominal aorta or the iliac artery to the 4 visceral arteries; the celiac, superior mesenteric, and bilateral renal arteries. To date, we have used the graft in hybrid repair of thoracoabdominal aortic aneurysm in 2 high-risk elder patients who had disseminated intravascular coagulopathy and severe renal failure, respectively. We found that a knitted quadrifurcated graft was easy to handle and useful for reducing the number of anastomoses, which were expected to shorten the operation time. Postoperative courses were uneventful without paraplegia in either patient. Postoperative computed tomography showed excellent patency of the inversely applied quadrifurcated graft without any endoleak or migration in the thoracoabdominal stent. In conclusion, revascularization of 4 visceral arteries using a quadrifurcated graft should be considered a preferable option in hybrid treatment for thoracoabdominal aortic aneurysm.

Transesophageal Echocardiography Simulator Training: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

SUMMARY STATEMENT: We aimed to assess the learning effects of novice transesophageal echocardiography (TEE) simulator training and to identify gaps in existing studies. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the learning effects of novice TEE training with versus without simulators, searching published articles and proceedings in 6 major databases in June 2019. We included 9 RCTs (268 participants). Compared with nonsimulator training, TEE simulator training resulted in higher skill and knowledge posttraining test scores with large effect sizes (standardized mean difference = 0.81 for skill, 1.61 for knowledge; low-certainty evidence) and higher training satisfaction with a small effect size (standardized mean difference = 0.36; very low-certainty evidence). No RCTs reported training budget or patient outcomes. Additional well-designed studies with low risk of bias and large sample sizes are needed to provide reliable and robust findings and develop more effective TEE simulation-based training curricula.

Pre-clinical medical student cardiac point-of-care ultrasound curriculum based on the American Society of Echocardiography recommendations: a pilot and feasibility study.

BACKGROUND: Cardiac point-of-care ultrasound (POCUS) training has been integrated into medical school curricula. However, there is no standardized cardiac POCUS training method for medical students. To address this issue, the American Society of Echocardiography (ASE) proposed a framework for medical student cardiac POCUS training. The objective of this pilot study was to develop a medical student cardiac POCUS curriculum with test scoring systems and test the curriculum feasibility for a future definitive study. METHODS: Based on the ASE-recommended framework, we developed a cardiac POCUS curriculum consisting of a pre-training online module and hands-on training with a hand-held ultrasound (Butterfly iQ, Butterfly Network Inc., Guilford, CT, USA). The curriculum learning effects were assessed with a 10-point maximum skill test and a 40-point maximum knowledge test at pre-, immediate post-, and 8-week post-training. To determine the curriculum feasibility, we planned to recruit 6 pre-clinical medical students. We semi-quantitatively evaluated the curriculum feasibility in terms of recruitment rate, follow-up rate 8 weeks after training, instructional design of the curriculum, the effect size (ES) of the test score improvements, and participant satisfaction. To gather validity evidence of the skill test, interrater and test-retest reliability of 3 blinded raters were assessed. RESULTS: Six pre-clinical medical students participated in the curriculum. The recruitment rate was 100% (6/6 students) and the follow-up rate 8 weeks after training was 100% (6/6). ESs of skill and knowledge test score differences between pre- and immediate post-, and between pre- and 8-week post-training were large. The students reported high satisfaction with the curriculum. Both interrater and test-retest reliability of the skill test were excellent. CONCLUSIONS: This pilot study confirmed the curriculum design as feasible with instructional design modifications including the hands-on training group size, content of the cardiac POCUS lecture, hands-on teaching instructions, and hand-held ultrasound usage. Based on the pilot study findings, we plan to conduct the definitive study with the primary outcome of long-term skill retention 8 weeks after initial training. The definitive study has been registered in ClinicalTrials.gov (Identifier: NCT04083924).

Formation mechanism of TiO2-derived titanate nanotubes prepared by the hydrothermal process.

The structural change on the molecular scale of anatase-type TiO(2) during hydrothermal treatment was investigated in detail by various analytic techniques such as X-ray absorption fine structure and transmission electron microscopy in order to clarify the formation mechanisms of titanate-based nanotubes. It revealed that the nanosheet-like products composed of highly distorted TiO(6) octahedra were generated by hydrothermal treatment of anatase-type TiO(2), and then the anatase-like structures are partially built up with the formative nanotubes by scrolling up these nanosheet-like products and nanosheets.

Synthesis of novel structured TiO(2) with mesopores by anodic oxidation.

In this study, a simple anodic oxidation process resulted in the successful synthesis of novel N-ion-doped TiO(2) with one-dimensionally aligned and large-sized mesopores. TiO(2) obtained by this anodic oxidation process possessed the high values of specific surface area and a large amount of one-dimensional mesopores with 30-50 nm diameter. Furthermore, X-ray photoelectron spectroscopy and UV-vis results suggested the possibility that these TiO(2) products were composed of a N-ion-doped powder. Thus, novel structured TiO(2) with large-sized mesopores was simply synthesized by an anodic oxidation of Ti metal in a nitric acid solution. These uniquely nanostructured mesoporous TiO(2) products will expand possibilities for applying mesoporous TiO(2) in new fields.

Coadministration of carvedilol attenuates nitrate tolerance by preventing cytochrome p450 depletion.

BACKGROUND: Long-term administration of nitroglycerin (NTG) causes tolerance secondary to increased vascular formation of reactive oxygen species. Carvedilol, which has potent antioxidant activity in addition to functioning as an adrenergic blocker, prevents nitrate tolerance by a still to be elucidated mechanism. The present study investigated how carvedilol attenuates nitrate tolerance, particularly with reference to cytochrome P450 (CYP), an enzyme involved in the development of tolerance. METHODS AND RESULTS: Male Wistar rats were subjected to 48-h continuous infusion of NTG alone (0.5 mg/h) or NTG with concomitant carvedilol (20 or 100 microg/h), and then compared with vehicle-treated rats (4 groups; n=6 in each group). Following the continuous administration, nitrate tolerance, assessed by bolus NTG injections, was hemodynamically prevented by coadministration of carvedilol. Levels of CYP1A1/1A2, superoxide production, and phosphorylated vasodilator-stimulated phosphoprotein at serine 239 (P-VASP) were examined in the aortic wall and heart tissue. When NTG alone was continuously administered, vascular superoxide was produced, there was a decrease in the cardiac CYP1A1/1A2 level, and depletion of P-VASP. However, each of these changes induced by continuous NTG administration was significantly attenuated by coadministration of carvedilol and the extent of attenuation was more pronounced at the higher dose (100 microg/h). CONCLUSIONS: Coadministration of carvedilol attenuates nitrate tolerance through maintenance of NO/cGMP pathway activity by preventing free radical generation and CYP depletion.

Considerations in timing of surgical intervention for infective endocarditis with cerebrovascular complications.

BACKGROUND AND AIM OF THE STUDY: The timing of the surgical intervention for active infective endocarditis (IE) is particularly difficult when there is a cerebrovascular complication. The study aim was to investigate the results of surgical treatment for active IE in patients with recent cerebrovascular events, and to evaluate the relationship between the size of cerebral infarction and timing of the surgical intervention. METHODS: Between January 1991 and April 2009, the details of 21 patients with cerebrovascular complications before surgery were analyzed retrospectively. Types of complication included cerebral infarction (n = 13), hemorrhagic infarction (n = 4), and cerebral hemorrhage (n = 4). The surgical treatment was single valve surgery (n = 14), multiple valve surgery (n = 3), and modified Bentall surgery (n = 4). The mean interval between onset of the cerebrovascular event and surgical intervention was 27.0 +/- 18.8 days. RESULTS: Eight patients underwent surgery within two weeks; among these patient, seven had a small cerebral infarction (< or = 15 mm diameter) and one patient had a cerebral hemorrhage. Postoperative exacerbation of cerebral complications was not observed among the eight patients treated within two weeks. The interval between onset of the cerebral event and cardiac surgery was significantly shorter in patients with a small infarction (18 days) than with a large infarction (38 days) (p < 0.05). None of the patients with a small infarction had postoperative exacerbation of their cerebral complication, even with a significantly shorter interval. However, postoperative hemorrhage into the infarction area was observed in one patient with a large infarction. CONCLUSION: The study results showed that IE patients with a small non-hemorrhagic cerebral infarction may safely undergo cardiac surgery, even within two weeks of the onset of a cerebrovascular event.

Imparting CO2 reduction selectivity to ZnGa2O4 photocatalysts by crystallization from hetero nano assembly of amorphous-like metal hydroxides.

Imparting an enhanced CO2 reduction selectivity to ZnGa2O4 photocatalysts has been demonstrated by controlled crystallization from interdispersed nanoparticles of zinc and gallium hydroxides. The hydroxide precursor in which Zn(ii) and Ga(iii) are homogeneously interdispersed was prepared through an epoxide-driven sol-gel reaction. ZnGa2O4 obtained by a heat-treatment exhibits a higher surface basicity and an enhanced affinity for CO2 molecules than previously-reported standard ZnGa2O4. The enhanced affinity for CO2 molecules of the resultant ZnGa2O4 leads to highly-selective CO evolution in CO2 photo-reduction with H2O reductants. The present scheme is promising to achieve desirable surface chemistry on metal oxide photocatalysts.

Impact of non-di-(2-ethylhexyl)phthalate cardiopulmonary bypass tubes on inflammatory cytokines and coagulation-fibrinolysis systems during cardiopulmonary bypass.

Di-(2-ethylhexyl)phthalate (DEHP), an excellent plasticizer for poly(vinyl chloride) (PVC), is a known endocrine-disrupting chemical. This study was designed to investigate whether a new non-DEHP bilayer tube reduced the release of DEHP, suppressed inflammatory cytokines, and altered coagulation-fibrinolysis systems. Sixteen patients undergoing coronary artery bypass grafting (CABG) were randomly assigned to the non-DEHP bilayer group (group B, n = 8), or the noncoated PVC group (group N, n = 8). The level of DEHP in the blood was measured before and after cardiopulmonary bypass (CPB). The levels of interleukin-6 (IL-6), D-dimer, and thrombin-antithrombin complex (TAT) were also measured at six points during and after CPB. DEHP was significantly lower in group B (472 +/- 141 ng/ml) after CPB compared with group N (2094 +/- 1046 ng/ml). The IL-6 level was significantly lower in group B (151 +/- 131 pg/ml) than group N (206 +/- 224 pg/ml) 180 min after protamine administration. The D-dimer level was significantly lower in group B 60 min after protamine administration (6.2 +/- 2.4 microg/ml in group B vs 10.4 +/- 4.5 microg/ml in group N) and 180 min after protamine administration (4.4 +/- 0.7 microg/ml in group B vs 7.3 +/- 2.7 microg/ml in group N). Group B had a tendency toward reduced postoperative bleeding compared with group N at any time. The bilayer tube was superior to the noncoated tube in terms of the inhibition of DEHP release, inflammatory cytokines, and the fibrinolysis system.

Methane dehydroaromatization over Mo-modified H-MFI for gas to liquid catalysts.

For direct gas to liquid (GTL), a novel process producing energy sources for methane dehydroaromatization is needed. Supporting MoO3 on H-MFI zeolite shows the high catalytic capacity and a selective activity for dehydroaromatization of methane to benzene at 973 K in a fixed bed reactor. On the other hand, deactivation by coke on the active sites in all the catalysts is formed during the reaction. H2 co-feed suppressed the deactivation, which is probably due to the decrease in coking amount. Mo K-edge X-ray absorption fine structure (XAFS) results showed the formation of dispersed Mo2C species with low crystallinity after dehydroaromatization. Mo L(III)-edge XANES (X-ray absorption near-edge structure) indicated the formation of active Mo species including Mo2C and Mo-oxycarbide (MoOxCy), where the redox state should be independent in the absence/presence of H2. It is concluded that Mo-oxycarbide species act as highly active species, and their stability affected the durable activity in the presence of H2.