Engineering pH-Responsive, Self-Healing Vesicle-Type Artificial Tissues with Higher-Order Cooperative Functionalities

Multicellular organisms demonstrate a hierarchical organization where multiple cells collectively form tissues, thereby enabling higher-order cooperative functionalities beyond the capabilities of individual cells. Drawing inspiration from this biological organization, assemblies of multiple protocells are developed to create novel functional materials with emergent higher-order cooperative functionalities. This paper presents new artificial tissues derived from multiple vesicles, which serve as protocellular models. These tissues are formed and manipulated through non-covalent interactions triggered by a salt bridge. Exhibiting pH-sensitive reversible formation and destruction under neutral conditions, these artificial vesicle tissues demonstrate three distinct higher-order cooperative functionalities: transportation of large cargoes, photo-induced contractions, and enhanced survivability against external threats. The rapid assembly and disassembly of these artificial tissues in response to pH variations enable controlled mechanical task performance. Additionally, the self-healing property of these artificial tissues indicates robustness against external mechanical damage. The research suggests that these vesicles can detect specific pH environments and spontaneously assemble into artificial tissues with advanced functionalities. This leads to the possibility of developing intelligent materials with high environmental specificity, particularly for applications in soft robotics.

Induction for Self-Propelled Motion of Artificial Objects with/without Shape Anisotropy

Motion is an essential feature of living systems. Microorganisms autonomously change their nature in response to slight changes in the surrounding environment induced by external stimuli and exhibit unique motion modes. Various self-propelled objects have been constructed to understand these behaviors. Towards achievement of such purpose, the precise settings of experimental conditions including fabrication of objects with a shape anisotropy have been made attempts in the field of active matter and supramolecular chemistry. This review describes the recent progress in inducing the self-propelled motion of artificial objects. If life-like dynamic behavior such as self-propelled motion can be designed and experimentally induced from molecular properties, it will be easier to control functions expressed as outputs. This will lead to not only a better understanding of the complex functions in living systems, but also the fabrication of exotic materials with life-like properties.

Investigation on the Validity of in vitro Sun Protection Factor and Ultraviolet-A Protection Factor Evaluation Method for Sunscreen Samples

Factors affecting the in vitro Sun Protection Factor (SPF) and Ultraviolet-A Protection Factor (UVA-PF) of sunscreens were analyzed for verifying the validity and reliability of the ISO24443 evaluation method. UV absorbance measurements by different spectrophotometers did not lead to the large difference in in vitro SPF/UVA-PF, although the UV absorbance determined by each spectrophotometer exhibited relatively large difference when it was larger than 2. On the other hand, relatively large difference was found in in vitro SPF/UVA-PF by utilizing European Cosmetic and Perfumery Association (Colipa) 1994 or UV-solar simulated radiation (UV-SSR) for the spectral irradiance. Appropriateness of employing the coefficient of adjustment for the determination of in vitro UVA-PF was also found to be reexamined.

Spot Overtaking of Dyes of Their Chromatographic Development Associated with Solvent Evaporation

Infiltration of binary solution of hexane and ethanol into chromatography paper associated with their evaporation was found to generate unexpected initial rapid advancement of wicking front followed by its receding and readvancing in our previous research. In the present study, paper chromatography development of hydrophobic dye, Sudan III, and hydrophilic dye, Acid Blue 9, was carried out using binary solutions of hexane and ethanol in open environment, allowing the developing solvent been evaporated. Sudan III was developed with initial rapid advancing wicking front, while Acid Blue 9 was scarcely developed. On the other hand, Acid Blue 9 was developed with the readvancing second wicking front, while the spot of Sudan III scarcely migrated. Thus, the unexpected illusional phenomenon, overtaking the spot of Sudan III by the spot of Acid Blue 9, was observed. The readvancement of the second wicking front was found to be enhanced as increasing the relative humidity in the environment. Surface temperature of the chromatography paper was measured during the chromatographic development in open environment to show that it became lower than the dew point when the experiments were carried out in relatively high humidity. Solubility of Sudan III in a binary solution of ethanol and water remarkably decreased as increasing the content of water. It was thus suggested that the water vapor condensation to induce water mixing into the mobile phase to decrease the solubility of Sudan III to inhibit its chromatographic development to realize the illusional spot overtaking of dyes of their chromatographic development associated with solvent evaporation.

In vitro Evaluation Method of UV Protecting Ability of Sunscreens: Clarifying and Overcoming Problems to Develop New Method

Factors influencing on in vitro evaluation of UV protecting ability of sunscreens were analyzed. It was found that any factors making the sunscreen layer spatially inhomogeneous, such as directional viscous fingering during the sunscreen application, dewetting of applied sunscreen layer, and the surface roughness of the standard PMMA plate, alter the UV transmittance. New application procedure and new type of flat hydrophilic plate were developed for inhibiting the generation of spatial inhomogeneity in applied sunscreen layer. The method created by the combination of these newly developed technologies succeeded in providing reliable and reproducible in vitro evaluation of UV protecting ability.

Bifurcation and Transposition of the Wicking Front of Binary Solutions Infiltrating into Chromatography Paper Associated with Their Evaporation

Nonequilibrium fluid patterns, such as Marangoni contraction, coffee rings, and tears of wine, are generated in binary solutions spread on a substrate during their evaporation. In this study, we observed another type of nonequilibrium behavior exhibited by binary solutions as they infiltrate porous materials and undergo evaporation. A binary solution comprising hexane and ethanol was brought into contact with the chromatography paper to facilitate infiltration into the paper's pores. Because the experimental setup was in an open environment, infiltration and evaporation occurred simultaneously. The wicking front exhibited an initial rapid advancement, followed by subsequent receding and readvancing. Additionally, the bifurcation of the wicking front after the onset of its readvancement was confirmed by monitoring the temporal evolution of the spatial luminance distribution and temperature distribution on the surface of the chromatography paper. Chromatographic development of a hydrophilic dye was conducted in this experimental setup in an open environment. Additionally, it was confirmed that the receding and readvancing of the wicking front represented the transposition of the bifurcated wicking fronts.

Factors to control the alignment of surface-treated titanium dioxide powders to maximize performance of sunscreens

OBJECTIVE

Titanium dioxide powders are contained in a large class of colour cosmetics and sunscreen formulas. When they are used, the formation of a uniform functional powder layer on the skin is an important factor to show their functionality, such as aesthetic and UV protection. Attempts were made to extract the factors that affect the UV shielding ability of the deposited powder layer.

METHODS

Seven kinds of surface treatments were conducted on nano-sized titanium dioxide powder to modify the surface characteristics. Dispersion samples were prepared by mixing these powders with liquids, such as mixed solutions of cyclopentasiloxane, isododecane, coconuts alkane and dimethicone using a disperser and a bead mill. The dispersions were applied using an applicator on cellulose triacetate film, polycarbonate film and polymethyl pentene film. Laser microscope observation and micro-gloss glossmeter analysis were carried out to assess the flatness of the deposited powder layers, and the UV shielding ability was evaluated using SPF analyser.

RESULTS

Factors whose influences on the structure and UV shielding ability of the deposited powder layer being analysed were pseudo-HLB of the powders, liquids for preparing the dispersions and material of the substrates. Higher UV shielding ability was attained when powders having pseudo-HLB at around 6 were employed independent from the kinds of liquids and substrates. Flatness of the deposited layer was found to enhance the UV shielding ability of the UV-B region, while that of the UV-A region was scarcely influenced by the flatness. Employing lower surface tension liquids for preparing the dispersions and materials exhibiting lower polar components of surface free energy as substrates tended to enhance the UV shielding ability.

CONCLUSION

Surface treatments conducted on the powders in this study were found to change UV shielding ability, especially UV-B shielding ability, and the relation between pseudo-HLB and UV shielding ability was scarcely influenced by the kinds of liquids. Both surface tension of liquids and the polar component of surface free energy of substrates affected the UV shielding ability. It was suggested that pseudo-HLB calculated based on chemical structure becomes useful information to choose optimum surface treatment to make uniform powder alignment independent from the surrounding environment.

High thrombotic risk is associated with higher prevalence of suboptimal stent results in patients with high bleeding risk

Funding Acknowledgements

Type of funding sources: None.

Background

Shorter duration of dual antiplatelet therapy after drug-eluting stent implantation is required in patients with high bleeding risk (HBR) irrespective of the presence of concomitant high thrombotic risk (HTR). The prevalence of post-stent suboptimal findings in patients with HBR remains unclear.

Purpose

To clarify the prevalence of post-stent suboptimal findings assessed by optical coherence tomography (OCT) in patients with HBR according to the presence of HTR.

Methods

A total of 607 consecutive patients with stable coronary disease, who underwent OCT imaging of the culprit lesion were included. HBR was defined based on the Academic Research Consortium for High Bleeding Risk (ARC-HBR). HTR was defined as lesions with diffuse long (≧60 mm), treated with more than three stents, chronic total occlusion or diffuse long lesion (≧32 mm) in patients with diabetes mellitus. Post-stent suboptimal OCT criteria was defined as minimum stent area (MSA) <4.5 mm2, edge dissection and stent malapposition.

Results

The prevalence of HBR was 55.8%. The prevalence of HTR was significantly higher in patients with HBR than in those without HBR (35.0 vs. 26.6%, p=0.028) (Figure A). Among patients with HBR, the prevalence of post-stent suboptimal OCT criteria was significantly higher in patients with HTR than in those without HTR (86.2 vs. 64.7%, p<0.001), mainly due to the higher prevalence of MSA <4.5 mm2 (Figure B) in patients with HTR.

Conclusions

HTR was associated with a higher prevalence of post-stent suboptimal findings among patients with HBR. The present results may suggest the importance of optimal stenting in patients with HBR, particularly in those with concomitant HTR.

Higher triglyceride level is associated with the higher prevalence of layered plaque in nonculprit coronary plaques

Background

The impact of the high triglyceride (TG) level on the characteristics of coronary plaque in nonculprit lesion remains to be elucidated.

Purpose

To clarify the association between the TG level and the characteristics of nonculprit coronary plaque in patients with stable coronary disease using optical coherence tomography (OCT).

Methods

A total of 531 consecutive patients who underwent OCT imaging of the nonculprit lesion were included. Patients were classified into either the higher TG group (non-fasting TG ≥150 mg/dL, n=197) or the lower TG group (non-fasting TG <150 mg/dL, n=334). The morphologies of nonculprit plaque assessed by OCT were compared between the two groups.

Results

The median (interquartile range) of TG in the two groups was 193.0 (168.0–244.0) mg/dL and 95.0 (75.0–120.0) mg/dL, respectively. The prevalence of layered plaque was significantly higher in the higher TG group than the lower TG group (40.1 vs. 27.5%, p=0.004), whereas the prevalence of other plaque components was comparable between the two groups (Figure 1). The prevalence of layered plaque was significantly higher in the higher TG group than in the lower TG group among patients with diabetes mellitus (DM) (44.2 vs. 28.7%, p=0.037) although it was comparable between the two groups among patients without DM (Figure 2).

Conclusion

A higher TG level was associated with a higher prevalence of layered plaque in nonculprit plaques in patients with stable coronary disease, particularly in patients with DM. The present results may partly explain the impact of TG on the progression of coronary plaque and the increased incidence of recurrent events in patients with coronary artery disease.

Funding Acknowledgement

Type of funding sources: None.

pH-Sensitive Controlled Motion of Micrometer-sized Oil Droplets in a Solution of Surfactants Containing Fumaric Acid Derivatives

Self-propelled droplets are of considerable interest as an appropriate model for understanding the self-propulsion of objects in the fields of nonequilibrium physics and nonlinear science. Several research groups have reported the monodirectional motion of droplets, that is, chemotaxis, using stimuli-responsive materials. However, the precise control of chemotaxis remains challenging from the perspective of synthetic chemistry because chemotactic motion is primarily induced by the consumption of reactive oil or surfactants. Herein, we report a chemical system containing pH-responsive fumaric acid derivatives, in which the oil droplet exhibited positive chemotaxis over a wide pH range-from basic to acidic conditions. From the measurements of the interfacial tension between the oil and aqueous phases, it was deduced that the positive chemotaxis was due to heterogeneity in the interfacial tension of the droplet surface, which was accompanied by the production of surface-active compounds in the pH gradient in a linear-type channel.

High sensitivity C-reactive protein is associated with vulnerable characteristics in non-culprit plaques in patients with ST-segment elevation myocardial infarction

Funding Acknowledgements

Type of funding sources: None.

Background

Higher level of high sensitivity C-reactive protein (hsCRP) is associated with an increased risk of recurrent cardiovascular events in patients with ST-segment elevation myocardial infarction (STEMI). However, the association between hsCRP and the characteristics of non-culprit plaques in patients with STEMI remains to be elucidated.

Purpose

To clarify the morphological characteristics of non-culprit plaque in patients with STEMI according to the hsCRP levels using optical coherence tomography (OCT).

Methods

A total of 79 non-culprit plaques in 76 consecutive patients with STEMI, who underwent OCT imaging of the non-culprit plaques in a culprit vessel were included. The characteristics of non-culprit plaques assessed by OCT were compared between the higher hsCRP group (hsCRP ≥ 0.16 mg/dL, 38 plaques in 38 patients) and the lower hsCRP group (hsCRP < 0.16 mg/dL, 41 plaques in 38 patients).

Results

The prevalence of plaque with macrophage (63.2 vs. 31.7%, p = 0.006), plaque with large lipid (maximal lipid arc > 180 °) (57.9 vs. 31.7%, p = 0.018), healed plaque (50.0 vs. 26.8%, p = 0.045) and cholesterol crystal (18.4 vs. 2.4%, p = 0.045) was significantly higher in the higher hsCRP group than in the lower hsCRP group (Figure). In a multivariate analysis, the higher hsCRP was independently associated with the presence of plaque with macrophage (Odds ratio [OR], 3.031; 95% confidence interval [CI]: 1.112-8.264, p = 0.030), plaque with large lipid (OR, 2.897; 95% CI: 1.122-7.478, p = 0.026) and healed plaque (OR, 2.666; 95% CI: 1.030-6.896, p = 0.040).

Conclusions

Higher level of hsCRP is associated with a higher prevalence of vulnerable characteristics in non-culprit plaques in patients with STEMI. The present results may partly explain the pathogenesis of an increased incidence of recurrent cardiovascular events in patients with STEMI. Abstract Figure.

New in vitro SPF Evaluation Method for Hydrophilic Sunscreen Samples

A new method was developed for the in vitro sun protection factor (SPF) evaluation of sunscreen samples. A new type of substrate, a hydroxyalkyl cellulose-coated plate, was also prepared specifically for hydrophilic samples. This new substrate was required because hydrophilic samples would be unlikely to wet the surface of the standard cosmetic PMMA UV evaluation plate. A super-hydrophilic quartz plate was prepared by corona-discharge treatment before an aqueous solution of hydroxyalkyl cellulose was spread on it. A flat and uniform hydroxyalkyl cellulose film was subsequently formed through the evaporation of water. Special care was taken to inhibit the generation of spatial non-uniformity. Six hydrophilic sunscreen samples with in vivo SPF values of 56, 55, 52, 25, 15, and 4, were then applied to the prepared hydroxyalkyl cellulose-coated plate, as well as a super-hydrophilic quartz plate and a flat hydrophobic PMMA plate. The thicknesses of the applied layers were determined using a wheel-shaped wet film thickness gauge immediately after the application, and UV transmission was measured using an SPF analyzer. The value of in vitro SPF was calculated from the UV absorbance and the thickness of the layer. For two out of the six samples, PMMA plate could not be available, as the samples were unable to wet the PMMA surface. Relatively small differences were observed between the in vitro SPF values when the super-hydrophilic and hydroxyalkyl cellulose-coated plates were used. Samples exhibiting higher in vivo SPF were also associated with higher in vitro SPF values, although a linear relationship was not observed. In contrast to the super-hydrophilic plate whose half-life of the super-hydrophilicity is only approximately five days, the hydrophilicity of the hydroxyalkyl cellulose-coated plate scarcely varied during six months of storage. Finally, a simplified evaluation method was also proposed. The validity of the method was verified through a ring test where three researchers employed this method in different laboratories at three independent organizations.

Self-Assembling Properties and Recovery Effects on Damaged Skin Cells of Chemically Synthesized Mannosylerythritol Lipids

Mannosylerythritol lipids (MELs), which are one of the representative sugar-based biosurfactants (BSs) produced by microorganisms, have attracted much attention in various fields in the sustainable development goals (SDGs) era. However, they are inseparable mixtures with respect to the chain length of the fatty acids. In this study, self-assembling properties and structure-activity relationship (SAR) studies of recovery effects on damaged skin cells using chemically synthesized MELs were investigated. It was revealed, for the first time, that synthetic and homogeneous MELs exhibited significant self-assembling properties to form droplets or giant vesicles. In addition, a small difference in the length of the fatty acid chains of the MELs significantly affected their recovery effects on the damaged skin cells. MELs with medium or longer length alkyl chains exhibited much higher recovery effects than that of C18-ceramide NP.

Pathway-Dependent Phase Transitions of Supramolecular Self-assemblies Containing Cationic Amphiphiles with Azobenzene and Disulfide Groups

There have been several attempts to construct supramolecular chemical systems that mimic the phase transitions in living systems. However, most of these phase transitions are one-to-one and induced by one stimulus or chemical; there have been few reports on the pathway-dependent phase transition of supramolecular self-assemblies in multi-step. To induce multistep phase transitions, molecular crystals were prepared that contained a cationic amphiphile bearing azobenzene and disulfide groups. A reducing agent caused the crystals to become vesicles, and adjacent, non-touching vesicles fused under UV and subsequent visible light. Adding a reducing agent to the worm-like aggregates that were generated after UV irradiation of the original crystals resulted in the growth of sheet-like aggregates. ¹ H NMR and fluorescence anisotropy measurements showed that a series of phase transitions was induced by changes in the phase structures from molecular conversions of the reactive amphiphiles. The multiple pathway-dependent phase transitions of supramolecular self-assemblies can provide a methodology for developing new stimuli-responsive materials that exhibit the desirable properties under specific circumstances from a systems chemistry viewpoint.

Major hepatectomy with combined vascular resection for perihilar cholangiocarcinoma

Background

Hepatectomy with vascular resection (VR) for perihilar cholangiocarcinoma (PHCC) is a challenging procedure. However, only a few reports on this procedure have been published and its clinical significance has not been fully evaluated.

Methods

Patients undergoing surgical resection for PHCC from 2002–2017 were studied. The surgical outcomes of VR and non-VR groups were compared.

Results

Some 238 patients were included. VR was performed in 85 patients. The resected vessels were hepatic artery alone (31 patients), portal vein alone (37 patients) or both (17 patients). The morbidity rates were almost the same in the VR (49.4 per cent) and non-VR (43.8 per cent) groups (P = 0.404). The mortality rates of VR (3.5 per cent) and non-VR (3.3 per cent) were also comparable (P > 0.999). The median survival time (MST) was 45 months in the non-VR group and 36 months in VR group (P = 0.124). Among patients in whom tumour involvement was suspected on preoperative imaging and whose carbohydrate antigen 19-9 (CA19-9) value was 37 U/ml or less, MST in the VR group was significantly longer than that in the non-VR group (50 versus 34 months, P = 0.017). In contrast, when the CA19-9 value was greater than 37 U/ml, MST of the VR and non-VR groups was comparable (28 versus 29 months, P = 0.520).

Conclusion

Hepatectomy with VR for PHCC can be performed in a highly specialized hepatobiliary centre with equivalent short- and long-term outcomes to hepatectomy without VR.

How to Control Powder Alignment to Maximize Functionality and Performance of Color Cosmetics and Sunscreen

Control of powder alignment is essential for maximizing the functionality of color cosmetics and sunscreens. Various surface treatments were applied to nanosized titanium dioxide to modify their surface characteristics. Such modifications can be used to control the behavior of dispersions in cosmetics, enabling them to align uniformly. The powders were mixed with solvents and applied to a cellulose triacetate film. The features of powder alignment on the film were evaluated using several approaches. When the type of surface treatment changed by varying the weight ratio, there was no significant correlation between its alignment and treatment. However, when we focused on the pseudo-HLB each treated pigment, their alignments were correlated. It was confirmed that the powders subjected to the appropriate surface treatment combinations from the pseudo-HLB standpoint made it possible to align uniformly and create a smooth coating film. As a result, it has a high UV-shielding ability. The surface-treated powders in this study were found to change the UV shielding ability and surface roughness of the layer formed when they were formed by spreading the sample powder dispersion and drying of the film. It was suggested that the pseudoHLB, which is calculated based on the chemical structure after the surface treatment process, is useful for choosing the optimum surface treatment to create a uniformly aligned pigment layer.

Neck Location on the Outer Convexity is a Predictor of Incomplete Occlusion in Treatment with the Pipeline Embolization Device: Clinical and Angiographic Outcomes

BACKGROUND AND PURPOSE

With the increasing use of the Pipeline Embolization Device for the treatment of aneurysms, predictors of clinical and angiographic outcomes are needed. This study aimed to identify predictors of incomplete occlusion at last angiographic follow-up.

MATERIALS AND METHODS

In our retrospective, single-center cohort study, 105 ICA aneurysms in 89 subjects were treated with Pipeline Embolization Devices. Patients were followed per standardized protocol. Clinical and angiographic outcomes were analyzed. We introduced a new morphologic classification based on the included angle of the parent artery against the neck location: outer convexity type (included angle,  <160°), inner convexity type (included angle,  >200°), and lateral wall type (160° ≤ included angle  ≤200°). This classification reflects the metal coverage rate and flow dynamics.

RESULTS

Imaging data were acquired in 95.3% of aneurysms persistent at 6 months. Complete occlusion was achieved in 70.5%, and incomplete occlusion, in 29.5% at last follow-up. Multivariable regression analysis revealed that 60 years of age or older (OR, 5.70; P = .001), aneurysms with the branching artery from the dome (OR, 10.56; P = .002), fusiform aneurysms (OR, 10.2; P = .009), and outer convexity-type saccular aneurysms (versus inner convexity type: OR, 30.3; P < .001; versus lateral wall type: OR, 9.71; P = .001) were independently associated with a higher rate of incomplete occlusion at the last follow-up. No permanent neurologic deficits or rupture were observed in the follow-up period.

CONCLUSIONS

The aneurysm neck located on the outer convexity is a new, incomplete occlusion predictor, joining older age, fusiform aneurysms, and aneurysms with the branching artery from the dome. No permanent neurologic deficits or rupture was observed in the follow-up, even with incomplete occlusion.

Plaque erosion is associated with less systemic atherosclerosis than other plaque types of acute coronary syndrome

Background

Previous studies have demonstrated that plaque erosion is associated with less atheromatous plaque at both culprit and non-culprit lesion than other plaque types of acute coronary syndrome (ACS). However, the status of systemic atherosclerosis in patients with plaque erosion remains to be elucidated.

Purpose

To clarify if plaque erosion is associated with less systemic atherosclerosis than other plaque types of ACS.

Methods

A total of 239 consecutive patients with ACS who underwent optical coherence tomography (OCT) imaging of the culprit lesion were enrolled. Patients were classified into either plaque erosion (PE, n=45) or non-plaque erosion (non-PE, n=194) including plaque rupture and calcified nodule based on OCT findings of the culprit lesions. The status of systemic atherosclerosis was assessed by the findings of carotid echography, the severity of aortic arch calcification (AAC; grade 0–3) on chest X-ray, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial pressure index (ABPI).

Results

The maximum intima media thickness (IMT) was significantly thinner in the PE group than in the non-PE group (1.9±0.8 vs. 2.3±0.9 mm, p=0.023) (Panel A). The prevalence of heterogeneous plaque and calcified plaque was significantly lower in the PE group than in the non-PE group (25.0 vs. 50.4%, p=0.010, 18.8 vs. 38.5%, p=0.037, respectively). The prevalence of AAC grade was significantly different between the two groups with a tendency toward lower AAC grade in the PE group than the non-PE group (Panel B). The mean baPWV (1588.1±420.6 vs. 1686.5±363.5 cm/sec, p=0.186) and ABPI (1.1±0.1 vs. 1.1±0.1, p=0.270) was comparable between the two groups.

Conclusion

Plaque erosion was associated with less atherosclerosis in carotid artery and aortic arch than non-plaque erosion. These findings may help further clarify the distinct pathophysiology of plaque erosion.

Funding Acknowledgement

Type of funding source: None

Lower levels of low-density lipoprotein cholesterol are associated with lower prevalence of thin-cap fibroatheroma in statin-treated patients with coronary artery disease

Background

Lowering low-density lipoprotein cholesterol (LDL-C) with statins slows progression of atherosclerotic plaques and reduces cardiovascular events. The 2019 European Society of Cardiology guideline for the management of dyslipidaemias recommends the absolute LDL-C treatment target as &lt;55mg/dL for very high-risk patients, &lt;70 mg/dL for high-risk patients and &lt;100 mg/dL for moderate-risk patients. However, the difference in plaque composition of coronary lesions according to these LDL-C levels remains to be elucidated.

Purpose

To investigate plaque morphologies according to LDL-C levels in statin-treated patients with coronary artery disease (CAD).

Methods

A total of 685 consecutive statin-treated patients with CAD, who underwent optical coherence tomography (OCT) imaging of culprit lesions were enrolled. The prevalence of vulnerable compositions in culprit plaques evaluated by OCT was compared among the groups of patients classified by LDL-C levels (&lt;55, 55–70, 70–100, ≥100 mg/dL).

Results

LDL-C levels &lt;55 mg/dL, &lt;70 mg/dL and &lt;100 mg/dL were observed in 6.3%, 21.8% and 63.9% of patients, respectively. The prevalence of thin-cap fibroatheroma was significantly different among the groups (P=0.014, Figure) with a trend toward lower prevalence in the lower two LDL-C groups than in the higher two LDL-C groups. A gradient with lower prevalence of thrombus in lower LDL-C groups was observed, although the statistical significance was not demonstrated (Figure). There was no significant difference in the prevalence of macrophage or cholesterol crystal among the groups.

Conclusions

Lower LDL-C level was associated with a trend toward lower prevalence of thin-cap fibroatheroma and thrombus in statin-treated patients with CAD.

Funding Acknowledgement

Type of funding source: None

Higher level of high sensitivity C-reactive protein is associated with more fibrocalcific plaque and longer lesion in patients with acute coronary syndrome

Background

The association between the level of high sensitivity C-reactive protein (hsCRP) and coronary plaque characteristics in patients with acute coronary syndrome (ACS) remains to be elucidated.

Purpose

To clarify the morphological characteristics of culprit lesion in patients with ACS according to the hsCRP levels using optical coherence tomography (OCT).

Methods

A total of 215 consecutive patients with ACS, who underwent OCT imaging of culprit lesions were included. The patients were classified into either the higher hsCRP group (hsCRP ≥0.14 mg/dL, n=108) or the lower hsCRP group (hsCRP &lt;0.14 mg/dL, n=107) according to the median preprocedural hsCRP level. The morphological characteristics of culprit lesion assessed by OCT were compared between the two groups.

Results

The higher hsCRP group had higher prevalence of insulin therapy (14 vs. 6%, p=0.037) and current smoker than the lower hsCRP group (37 vs. 18%, p=0.002). The prevalence of long lesion (≥25 mm, 67 vs. 53%, p=0.041) and fibrocalcific plaque (53 vs. 33%, p=0.003) was significantly higher in the higher hsCRP group than in the lower hsCRP group (Figure). On the other hand, the prevalence of plaque rupture (36 vs. 46%, p=0.174) and lipid-rich plaque (47 vs. 64%, p=0.011) was rather lower in the higher hsCRP group than in the lower hsCRP group (Figure). In a multivariate analysis, fibrocalcific plaque (odds ratio [OR]: 2.098, 95% confidence interval [CI]: 1.125–3.913, p=0.019), lesion length (mm, OR: 1.036, 95% CI: 1.010–1.061, p=0.004) and current smoker (OR: 2.757, 95% CI: 1.388–5.476, p=0.003) was independently associated with higher hsCRP level.

Conclusions

ACS patients with high hsCRP levels had more fibrocalcific plaque and longer lesion than those with low hsCRP levels. The association between high hsCRP levels and vulnerable characteristics of culprit plaque was not demonstrated.

Funding Acknowledgement

Type of funding source: None

Developing and validating the Japanese version of professional attitude scale for nurses

Aim

We developed and psychometrically tested the Japanese version of the Professional Attitude Scale for Nurses (PASN‐J).

Background

Nurses must recognize the importance of their professionalism; therefore, it is critical to quantitatively measure nurses’ professional attitudes.

Introduction

This instrument validation study was designed to generate an itemized scale and examine its content validity/psychometric testing using a sample of Japanese nurses.

Methods

Based on a trait approach focusing on the characteristic traits of the nursing profession, a 59‐item draft scale was generated. During November 2017, 2657 nurses from 29 facilities in Japan were surveyed. The questionnaire included demographics, the 59‐item draft scale, and a self‐report scale of nurses’ professional behaviour and nursing practice ability. Using exploratory and confirmatory factor analyses, we evaluated the construct, criterion‐related, concurrent, and known‐groups validity, and reliability of the PASN‐J.

Results

Data from 1716 participants were analysed. The analyses yielded a 38‐item, 3‐factor scale that adequately fit the data. PASN‐J scores were positively correlated with nurses’ professional behaviour and nursing practice ability.

Conclusion

The 38‐item PASN‐J has good reliability and validity, making it useful for measuring the current condition of nursing professionalism and evaluating nursing education. Implications for Nursing and Health Policy: This scale can evaluate nursing education and promote nurses’ professionalism. The PASN‐J will help identifying the elements of undergraduate nursing education that require further emphasis. Additionally, the PASN‐J could facilitate the development of nursing policies to promote professional development in nurses. Ultimately, evaluating nursing education with the PASN‐J enhances nurses’ professional attitudes and subsequently improves their quality of nursing, nursing efficiency and patient outcomes.

pH-Tolerant giant vesicles composed of cationic lipids with imine linkages and oleic acids

Giant vesicles (GVs) have attracted attention as functional materials because they can encapsulate both hydrophilic and hydrophobic compounds. For next generation functional GVs, both tolerance and stimuli-sensitivity are needed. So far, vesicles tolerant to acidic or basic conditions were generated using a mixture of cationic lipids and fatty acids. Here, to create functional GVs that are tolerant to a wide pH range but sensitively respond at below a specific pH, the behaviour of GVs composed of a cationic lipid with an imine bond and oleic acid was investigated. Even though the GVs prepared by the film swelling method were tolerant to strongly acidic conditions, GVs without oleic acid gradually shrank, accompanied by the generation of oil droplets at the same pH. ¹H NMR analysis revealed that during hydration of the film, the imine bond hydrolysed to provide a cationic surfactant and an oil component in the presence of oleic acid due to its own Lewis basicity, suggesting the dissociation of oleic acid. The results of fluorescence spectroscopy using an environment-responsive probe and IR spectroscopy indicated that the GV tolerance originated from the intermolecular interactions of cationic lipids and anionic oleate.

Giant vesicles composed of cationic lipids having an imine linkage and oleic acid were stable at strong acidic conditions.

Temperature-Dependent Dynamics of Giant Vesicles Composed of Hydrolysable Lipids Having an Amide Linkage

Various amphiphiles including surfactants and lipids have been designed and synthesized to improve and create new functionalities. In particular, the emergence of cell-like behaviors of giant vesicles (GVs) composed of synthetic lipids has drawn much attention in the development of chemical models for cells. The aim of this study was to measure temperature-dependent morphological changes of GVs induced by fragmentation and subsequent growth using hydrolysable cationic lipids having an amide linkage. Results from differential scanning calorimetry, fluorescence spectroscopy using an environment-responsive probe, and confocal Raman microscopy showed that the dynamics observed were due to changes in the vesicle membrane, including variation in the lipid composition, induced by thermal stimulation.

Addition of low-dose liraglutide to insulin therapy is useful for glycaemic control during the peri-operative period: effect of glucagon-like peptide-1 receptor agonist therapy on glycaemic control in patients undergoing cardiac surgery (GLOLIA study)

AIM

To test the hypothesis that the addition of a glucagon-like peptide-1 receptor agonist that can decrease glucose levels without increasing the hypoglycaemia risk will achieve appropriate glycaemic control during the peri-operative period.

METHODS

We studied 70 people with Type 2 diabetes who underwent elective cardiac surgery. Participants were randomized to either an insulin-alone or an insulin plus liraglutide 0.6 mg/day group. We evaluated average M values, which indicated the proximity index of the target glucose level from day 1 to day 10.

RESULTS

The average M value in the liraglutide plus insulin group was significantly lower than that in the insulin-alone group (liraglutide plus insulin 5.8 vs insulin-alone 12.3; P < 0.001). The frequency of insulin dose modification in the liraglutide plus insulin group was significantly lower than that in the insulin-alone group (odds ratio 0.19, 95% CI 0.08-0.49; P < 0.001). The frequency of hypoglycaemia in the liraglutide plus insulin group tended to be lower than that in the insulin-alone group (odds ratio 0.57, 95% CI 0.15-2.23; P = 0.21).

CONCLUSIONS

The results of this study showed that the addition of low-dose liraglutide to insulin achieved lower M values than insulin alone, suggesting that the addition of low-dose liraglutide may achieve better glycaemic control during the peri-operative period. (Clinical trials registry no.: UMIN 000008003).

Start of Micrometer-Sized Oil Droplet Motion through Generation of Surfactants

Self-propelled motion of micrometer-sized oil droplets in surfactant solution has drawn much attention as an example of nonlinear life-like dynamics under far-from-equilibrium conditions. The driving force of this motion is thought to be induced by Marangoni convection based on heterogeneity in the interfacial tension at the droplet surface. Here, to clarify the required conditions for the self-propelled motion of oil droplets, we have constructed a chemical system, where oil droplet motion is induced by the production of 1,2,3-triazole-containing surfactants through the Cu-catalyzed azide-alkyne cycloaddition reaction. From the results of the visualization and analysis of flow fields around the droplet, the motion of the droplets could be attributed to the formation of flow fields, which achieved sufficient strength caused by the in situ production of surfactants at the droplet surface.

P2805Initial pathological responses of third-generation everolimus-eluting stents implantation: comparison with second-generation everolimus-eluting stents

Background

Third-generation drug-eluting stent (3rd DES) is commonly used now in percutaneous coronary intervention, and it has not only thinner struts, easier delivery than second-generation drug-eluting stent (2nd DES), but also abluminal biodegradable polymer. Clinical superiority of 3rd DES has been demonstrated compared to 1st and 2nd DESs. However, pathological response after 3rd DES implantation remains unclear.

Purpose

Pathological study of coronary artery after 3rd DES implantation have not been reported as far as we have referred to the previous studies. This study aimed to examine the initial tissue response after 3rd DES and 2nd DES implantation within one year.

Methods

Using specimens obtained by autopsy, we compared the histology between 3rd DES (n=3, 8 histological sections) and 2nd DES (n=6, 41 histological sections) lesions within 1 year after stent implantation to evaluate early tissue reaction. Stent segments were fixed with 10% buffered formalin and embedded in plastic, followed by hematoxylin–eosin, Masson's trichrome and elastica van Gieson. Ratio of covered stent struts by neointima was calculated. The thickness of neointima and the area of fibrin deposition were morphometrically evaluated. The degree of inflammation around struts was examined semi-quantitatively (score 0–3).

Results

The ratio of covered struts and thickness of neointima of 3rd DES were 0.84±0.04 and 68.2±10.3μm, while those of 2nd DES were 0.69±0.05 and 30.4±4.8μm respectively. The inflammation score was similar between two groups (1.00±0.14 vs. 1.02±0.16). The area of fibrin deposition around the struts was larger in 3rd DES compared with 2nd DES (1276.6±490.3μm2 vs. 658.0±173.4μm2). These results suggest that the 3rd DES may obtain prompt as well as rich covering of struts in the initial term after DES implantation. Although the biological feature of the polymers in 3rd and 2nd DESs is different, the inflammatory responses after both 3rd and 2nd DESs implantation were similar, at least within one year after deployment. The degree of inflammation was mild, less than approximately 50 inflammatory cells (score 1) around the struts.

Conclusions

Our pathological analysis showed advanced healing process in 3rd DES compared with 2nd DES lesions in the viewpoint of strut coverage by neointima. Observation of long-term pathological response may be required to evaluate the superiority of bioabsorbable polymer in 3rd DES.

Antibody-mediated Remyelination: Relevance to Multiple Sclerosis

Intravenous immunoglobulin (IVIG) is widely used for treatment of autoimmune neurological disorders and is currently in clinical trials as a therapy for multiple sclerosis. We have previously demonstrated that certain mouse monoclonal antibodies of the IgM isotype, promote significant remyelination when administered to mice with chronic Theiler's murine encephalomyelitis virus-induced demyelinating disease. These IgM antibodies bind to antigens expressed on oligodendrocytes. We now demonstrate that polyclonal human IgG (IVIG) and polyclonal human IgM also promote remyelination in this system. Although both polyclonal human IgG and IgM promote remyelination, IgM is more potent Polyclonal human IgM also differs from human IgG in its ability to bind strongly to antigens expressed in the CNS and by oligodendrocytes. We propose that polyclonal IgG and polyclonal IgM may function to promote remyelination by different mechanisms. IVIG may function based on its immunomodulatory activity, while the activity of IgM is critically dependent upon its reactivity with CNS antigens. This possibility has clear relevance to the use of antibodies as a therapy for multiple sclerosis, suggesting that combined treatment with antibodies exerting immunomodulatory activity, in concert with antibodies that function through direct binding to CNS antigens, may synergize to enhance the efficacy of the therapy.

Surface Structures of Cosmetic Standard Poly Methyl Methacrylate UV Evaluation Plates and their Influence on the in vitro Evaluation of UV Protection Abilities of Cosmetic Sunscreens

Cosmetic standard poly methyl methacrylate (PMMA) UV evaluation plates, i.e., roughened PMMA plates, are used in the EU and the US for the in vitro evaluation of UV protection abilities of sunscreen, such as in vitro UVA-PF and critical wavelength for the Broad-spectrum approval. In our previous studies, inhomogeneity in the thickness of a pseudo-sunscreen layer applied on a flat quartz plate was observed to alter UV transmission. Thus, the surface roughness of the standard plates should have a significant influence on the in vitro evaluation. In the present study, we have analyzed the surface structures of three cosmetic standard PMMA UV evaluation plates: Helioplates HD6 (Sa = 6 µm) and ISO plates (Ra = 2 and 5 µm). A decamethylcyclopentasiloxane and 2-propanol-mixed solvent solution of acrylsilicone resin was prepared, and the solution was added dropwise onto the plates. After the evaporation of the solvents, the plates were cut and the cross section was analyzed using SEM-EDS. The distribution of silicon atoms at the cross-section suggested that the maximum depth of penetrating of acrylsilicone resin was larger than Ra for all the standard plates, and the surface structure was significantly different for each standard plate. In addition, cracks into which the acrylsilicone resin deeply penetrated were observed on the surface of some plates. Clear-solution-type pseudo-sunscreen samples in which UV absorbers and acrylsilicone resin were dissolved were deposited on the standard roughened PMMA plates. It was observed that the addition of acrylsilicone resin drastically changed the net UV transmission. The degree to which the hollows of the roughened surface were filled with the pseudo-sunscreen samples determined the variation of UV transmittance.

Locomotion Mode of Micrometer-Sized Oil Droplets in Solutions of Cationic Surfactants Having Ester or Ether Linkages

Micrometer-sized self-propelled oil droplets under a far-from-equilibrium condition have drawn much attention because of their potential as a dynamic model for the chemical machinery in living organisms. To clarify the effect of interactions between the system components (surfactant, oil, and water) on the locomotion mode of droplets, we investigated the behaviors of oil droplets composed of n-heptyloxybenzaldehyde (HBA) in solutions of cationic surfactants having or not having an ester or an ether linkage. It was observed that in solutions of cationic surfactants having an ester or an ether linkage, spherical HBA droplets self-propelled by changing their direction frequently. On the other hand, when this functional group is absent, a slow self-propelled motion of the oil droplets concurrent with the evolution of aggregates on their surface was observed. From the results of measurement of interfacial tension and assessment of self-emulsification, we determined that the attractive interactions of cationic surfactants without an ester or an ether linkage with HBA are stronger than those having the linkage. The difference in the locomotion mode of oil droplets is probably explained from the viewpoint of the interactions among the system components.

Sequential dynamic structuralisation by in situ production of supramolecular building blocks

We herein report an example of sequential dynamic higher structuralisation from disordered droplets into higher-ordered structures, resulting in the formation of a hydrogel. This is a potential model for understanding complicated biosystems in which lower-ordered structures evolve into higher-ordered structures that interact with specific molecules.

Phototactic behavior of self-propelled micrometer-sized oil droplets in a surfactant solution

We demonstrate the phototactic behavior of self-propelled micrometer-sized oil droplets in a far-from-equilibrium state.

Self-Propelled Oil Droplets and Their Morphological Change to Giant Vesicles Induced by a Surfactant Solution at Low pH

Unique dynamics using inanimate molecular assemblies based on soft matter have drawn much attention for demonstrating far-from-equilibrium chemical systems. However, there are no soft matter systems that exhibit a possible pathway linking the self-propelled oil droplets to formation of giant vesicles stimulated by low pH. In this study, we conceived an experimental oil-in-water emulsion system in which flocculated particles composed of a imine-containing oil transformed to spherical oil droplets that self-propelled and, after coming to rest, formed membranous figures. Finally, these figures became giant vesicles. From NMR, pH curves, and surface tension measurements, we determined that this far-from-equilibrium phenomenon was due to the acidic hydrolysis of the oil, which produced a benzaldehyde derivative as an oil component and a primary amine as a surfactant precursor, and the dynamic behavior of the hydrolytic products in the emulsion system. These findings afforded us a potential linkage between mobile droplet-based protocells and vesicle-based protocells stimulated by low pH.

Effect of CT digital image compression on detection of coronary artery calcification

Purpose: To test the effect of digital compression of CT images on the detection of small linear or spotted high attenuation lesions such as coronary artery calcification (CAC).

Material and Methods: Fifty cases with and 50 without CAC were randomly selected from a population that had undergone spiral CT of the thorax for screening lung cancer. CT image data were compressed using JPEG (Joint Photographic Experts Group) or wavelet algorithms at ratios of 10:1, 20:1 or 40:1. Five radiologists reviewed the uncompressed and compressed images on a cathode-ray-tube. Observer performance was evaluated with receiver operating characteristic analysis.

Results: CT images compressed at a ratio as high as 20:1 were acceptable for primary diagnosis of CAC. There was no significant difference in the detection accuracy for CAC between JPEG and wavelet algorithms at the compression ratios up to 20:1. CT images were more vulnerable to image blurring on the wavelet compression at relatively lower ratios, and "blocking" artifacts occurred on the JPEG compression at relatively higher ratios.

Conclusion: JPEG and wavelet algorithms allow compression of CT images without compromising their diagnostic value at ratios up to 20:1 in detecting small linear or spotted high attenuation lesions such as CAC, and there was no difference between the two algorithms in diagnostic accuracy.

Effects of JPEG and wavelet compression of spiral low-dose CT images on detection of small lung cancers

Purpose: To compare the effect of compression of spiral low-dose CT images by the Joint Photographic Experts Group (JPEG) and wavelet algorithms on detection of small lung cancers.

Material and Methods: Low-dose spiral CT images of 104 individuals (52 with peripheral lung cancers smaller than 20 mm and 52 control subjects) were used. The original images were compressed using JPEG or wavelet algorithms at a ratio of 10:1 or 20:1. Five radiologists interpreted these images and evaluated the image quality on a high-resolution CRT monitor. Observer performance was studied by receiver operating characteristic (ROC) analysis.

Results: There was no significant difference in the detection of cancers measuring 6 to 15 mm in uncompressed images and in those compressed by either of the algorithms, although the quality of images compressed at 20:1 with the wavelet algorithm was somewhat inferior. A lower diagnostic accuracy was noted using images compressed by the JPEG or wavelet algorithms at 20:1 in detecting lung cancers measuring 6 to 10 mm and cancers measuring from 6 to 15 mm with ground-glass opacity.

Conclusion: Compression of low-dose CT images at a ratio of 10:1 using JPEG and wavelet algorithms does not compromise the detection rate of small lung cancers.