Optimal application of compressive palatal stents following mesiodens removal in pediatric patients: A Randomized Controlled Trial

Background

There is no scientific evidence supporting the choice of a palatal stent in patients who underwent removal of an impacted supernumerary tooth. We aimed to investigate the effects of palatal stents in patients who underwent supernumerary tooth removal through a palatal approach and to suggest the optimal stent thickness and material.

Material and Methods

We recruited 144 patients who underwent extraction of a supernumerary tooth between the maxillary anterior teeth. Subjects were assigned to a control group (CG) or one of four compressive palatal stent groups (CPSGs) classified by the thickness and material of the thermoplastic acrylic stent used. Palatal gingival swelling and objective indices (healing, oral hygiene, gingival, and plaque) were evaluated before surgery and on postoperative days (PODs) 3, 7, and 14; pain/discomfort and the Child Oral Health Impact Profile (COHIP) were assessed as subjective indices of the effects of the stent.

Results

The CPSGs showed faster healing than did the CG on PODs 7 (P<0.001) and 14 (P=0.043); swelling was measured by 1.64±0.88 mm and 4.52±0.39 mm, respectively. Although swelling was least in the 4-mm hard group (0.92±0.33 mm), the difference compared with that in the 2-mm hard group (1.01±0.18 mm) was not significant (P=0.077). The CPSGs showed better COHIP (P<0.001-0.036) and pain scores (P<0.001) than did the CG on PODs 1-3.

Conclusions

Compressive palatal stents reduce discomfort by decreasing pain and alleviating swelling. Although a stent is effective regardless of its thickness and material, 2-mm hard stents maximized such positive effects with minimal discomfort.

Key words:Supernumerary tooth, tooth Extraction, postoperative care, oral Health, pediatric dentistry.

Surface-Modifying Effect of Zwitterionic Polyurethane Oligomers Complexed with Metal Ions on Blood Compatibility

BACKGROUND

To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix.

METHODS

We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process.

RESULTS

Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results.

CONCLUSION

With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion. Schematic explanation of the effect of zwitterionic polyurethane additives for blood-compatible and anti-bacterial bulk modification.

Pedagogy, Partnership, and Collaboration: A Longitudinal, Empirical Study of Serious Educational Gameplay in Secondary Biology Classrooms

The use of serious educational games has the potential to increase student learning outcomes in science education by providing students with opportunities to explore phenomena in ways that vary from traditional instruction; yet, empirical research to support this assertion is limited. This study aimed to explore deeply what learning gains were associated with the use of three serious educational games (SEGs) created for use in secondary biology classrooms that partner teachers implemented during a 2-week curriculum unit. This longitudinal, mixed method study includes a control year, in which we examined how six highly qualified teachers taught students (n = 407) a 2-week curriculum unit addressing cellular biology without the SEGs, followed by 2 years in which the teachers integrated the SEGs into the curriculum unit with students (n =871). Data were collected from multiple sources, including a validated content pre- and post-test measure, embedded gameplay data, participant observation, teacher interviews, and focus groups. Quantitative findings showed significant learning gains associated with students who experienced the game condition during year 2, when compared with the control condition. During the replication year (year 3), learning gains increased again, compared with year two. Although the SEGs did not change between years 2 and 3, teachers were provided real-time access to students' performance during gameplay. Thematic analysis of observation notes, teacher interviews, and student performance in-game identified four affordances teachers identified related to the use of serious educational games in their classrooms and the extended partnership model employed. Implications for researchers and game designers are discussed.

Machine learning for predicting fractional flow reserve based on optical coherence tomography in intermediate coronary stenosis

Background

Machine learning approaches using intravascular optical coherence tomography (OCT) to predict fractional flow reserve (FFR) have not been previously investigated. The objective of the study was to evaluate a machine learning method to estimate FFR based on intravascular OCT images in intermediate coronary lesions.

Methods

Data from both OCT- and wire-based FFR methods were obtained for lesions of the left anterior descending artery in 125 patients. Based on the total number of lesions, training and testing groups were partitioned at a ratio of 5:1. For the training group, 36 features, including 16 clinical and lesion characteristics, and 21 OCT features, were used to model machine learning-FFR. machine learning-FFR values were then derived for the testing group and compared with wire-based FFR values in terms of a diagnosis of ischemia (FFR &lt;0.8).

Results

Clinical and lesion characteristics and OCT features between the training and testing groups were similar. During the machine learning modeling of the training group, six important features of machine learning-FFR were identified: minimal luminal area, percentage of the stenotic area, lesion length, proximal luminal area, pre-procedural platelet count, and hypertension. machine learning-FFR values showed a good correlation (r=0.853, P&lt;0.001) with wire-based FFR values (Figure 1A). The diagnostic power of an FFR value less than 0.8, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of machine learning-FFR values for the testing group were 85.7%, 100%, 100%, 77.8%, and 90.5%, respectively (Figure 1B). Additionally, OCT-based machine learning-FFR values showed a good diagnostic accuracy compared with other image-based FFR values.

Conclusions

The OCT-based machine learning-FFR method can be used to simultaneously acquire information on both image and functional modalities using one invasive procedure, suggesting that it may be used to optimize treatments for intermediate coronary artery stenosis, as well as save time and cost.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Funded by the Korean government (MSIT) (no. 2017R1A2B2003191)

The Impact of Markov Chain Convergence on Estimation of Mixture IRT Model Parameters

A nonconverged Markov chain can potentially lead to invalid inferences about model parameters. The purpose of this study was to assess the effect of a nonconverged Markov chain on the estimation of parameters for mixture item response theory models using a Markov chain Monte Carlo algorithm. A simulation study was conducted to investigate the accuracy of model parameters estimated with different degree of convergence. Results indicated the accuracy of the estimated model parameters for the mixture item response theory models decreased as the number of iterations of the Markov chain decreased. In particular, increasing the number of burn-in iterations resulted in more accurate estimation of mixture IRT model parameters. In addition, the different methods for monitoring convergence of a Markov chain resulted in different degrees of convergence despite almost identical accuracy of estimation.

Modification of the RANKL-RANK-binding site for the immunotherapeutic treatment of osteoporosis

Here, we proposed the use of mutated RANKL as an immunogen for active immunization and to induce anti-cytokine antibodies for osteoporosis treatment.

INTRODUCTION

Osteoclasts are responsible for bone resorption in bone-related disorders. Anti-cytokine therapeutic antibodies such as denosumab are effective for the treatment of osteoporosis. However, problems with antibody manufacturing and the immunogenicity caused by multiple antibody doses have led to the use of auto-cytokines as immunogens to induce anti-cytokine antibodies.

METHODS

RANKL was point-mutated based on the crystal structure of the complex of RANKL and its receptor RANK.

RESULTS

As a proof of concept, immunization with RANKL produced high levels of specific antibodies and blocked osteoclast development in vitro and inhibited osteoporosis in RANKL-treated or ovariectomized mouse models.

CONCLUSIONS

The results demonstrate the successful use of mutated RANKL as an immunogen for the induction of anti-RANKL immune response. This strategy is useful in general anti-cytokine immunotherapy to avoid toxic side effects of osteoporosis treatment.

P4393Current smoking and gender difference in South Korean AMI patients who underwent PCI with DES

Background

There is some debate on whether or not there is a gender difference is present between current smoking and cardiovascular disease.

Purpose

We decide to evaluate the impact of sex difference on the 2-year clinical outcomes in Korean acute myocardial infarction (AMI) patients who currently smoke and who underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES).

Methods

The data of this study was obtained from the Korea Acute Myocardial Infarction (KAMIR) registry. More than fifty high-volume universites or community hospitals with facilities for primary PCI and onsite cardiac surgery participated in this KAMIR registry. A total of 12565 current smoker AMI patients were enrolled and divided into the male (n=11767, 93.6%) or female (n=798, 6.4%) group. The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), and total repeat revascularization.

Results

Before risk adjustment, the cumulative incidences of MACE (7.2% vs. 10.0%, hazard ratio [HR], 1.419; 95% confidence interval [CI], 1.125–1.790; P=0.003), all-cause death (HR, 1.988; 95% CI, 1.417–2.789; P<0.001), and re-MI (HR, 1.885; 95% CI, 1.154–3.078; P=0.011) were significantly higher in the female group compared with the male group. However, after adjustment the cumulative incidences of MACE (adjusted HR, 1.047; 95% CI, 0.756–1.450; P=0.782), all-cause death, re-MI, total repeat revascularization, TLR, TVR, and non-TVR were similar between the two groups.

Clinical outcomes at 2-year Outcomes Cumulative Events at 2-year (%) Unadjusted Adjusted* Propensity-score adjusted Male Female Log-rank Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value MACE 819 (7.2) 78 (10.0) 0.003 1.419 (1.125–1.790) 0.003 1.047 (0.756–1.450) 0.782 1.133 (0.871–1.473) 0.352 All-cause death 283 (2.5) 38 (4.8) <0.001 1.988 (1.417–2.789) <0.001 0.764 (0.457–1.279) 0.306 1.105 (0.744–1.641) 0.620 Cardiac death 224 (1.9) 25 (3.2) 0.016 1.654 (1.094–2.500) 0.017 0.512 (0.261–1.005) 0.052 0.822 (0.511–1.322) 0.419 Re-MI 142 (1.3) 18 (2.4) 0.010 1.885 (1.154–3.078) 0.011 1.741 (0.887–3.419) 0.107 1.835 (1.109–3.375) 0.062 Total revascularization 444 (4.0) 27 (3.6) 0.594 0.900 (0.610–1.327) 0.594 1.069 (0.654–1.748) 0.789 0.956 (0.627–1.458) 0.835 TLR 121 (1.1) 8 (1.1) 0.956 0.980 (0.479–2.004) 0.956 0.955 (0.366–2.497) 0.926 0.868 (0.395–1.910) 0.726 TVR 228 (2.1) 14 (1.9) 0.726 0.908 (0.529–1.558) 0.726 1.051 (0.518–2.135) 0.890 0.935 (0.519–1.684) 0.823 Non-TVR 223 (2.0) 13 (1.7) 0.602 0.862 (0.493–1.508) 0.602 1.060 (0.536–2.097) 0.867 0.942 (0.514–1.726) 0.847

Conclusion

Before risk adjustment, a gender difference was suggested in the female group compared with the male in these current smoker South Korean AMI patients during a 2-year follow-up period. However, after adjustment, gender difference was not observed in these AMI patients with a history of current smoking.

P833Two-year clinical outcomes between statin with ACE inhibitor or ARB in patients with ST-segment elevation myocardial infarction after successful PCI with DES

Background

Limited comparative data are available.

Purpose

We decided to compare 2-year major clinical outcomes between statin with ACEI and statin ARB therapy in patients with STEMI after PCI with drug-eluting stents (DES).

Methods

A total 11706 STEMI patients who underwent PCI with DES and who prescribed statin were enrolled and they were divided into two groups, the statin with ACEI group (n=8705) and the statin with ARB group (n=3001). The primary endpoint was the major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-TVR. The secondary endpoints were the cumulative incidences of individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR.

Results

Two PSM groups (2835 pairs, n=5670, C-statistic = 0.680) were generated. The relative risk of MACE was higher in the statin with ARB group compared to statin with ACEI groups after propensity score-matched (PSM) analysis (hazard ratio [HR]: 1.323, 95% confidence interval [CI]: 1.085–1.613, p=0.006). The relative risks of cardiac death (HR: 1.831, 95% CI: 1.199–2.740, p=0.005), total repeat revascularization (HR: 1.487, 95% CI: 1.133–1.950, p=0.004), and non-TVR (HR: 1.696, 95% CI: 1.122–2.564, p=0.012) were also higher in the statin with ARB group after PSM.

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Statin + ACEI Statin + ARB Log-rank Propensity score matched Patients MACE 173 (6.5) 225 (8.5) 0.006 1.323 (1.085–1.613) 0.006 All-cause death 58 (2.2) 80 (3.0) 0.054 1.391 (0.992–1.950) 0.056 Cardiac death 35 (1.3) 63 (2.3) 0.004 1.831 (1.199–2.740) 0.005 Re-MI 39 (1.5) 44 (1.7) 0.548 1.141 (0.742–1.756) 0.548 Total repeat revascularization 88 (3.4) 128 (4.9) 0.004 1.487 (1.133–1.950) 0.004 TLR 26 (1.0) 40 (1.5) 0.075 1.561 (0.953–2.558) 0.077 TVR 53 (2.0) 71 (2.8) 0.086 1.364 (0.955–1.946) 0.088 Non-TVR 36 (1.4) 60 (2.3) 0.011 1.696 (1.122–2.564) 0.012 TVF 140 (5.3) 173 (6.6) 0.050 1.249 (1.000–1.561) 0.050

Conclusions

In this study, we suggest that the combination of statin with ACEI may be beneficial for reducing the cumulative incidences of MACE, total repeat revascularization rate, and non-TVR rather than the statin with ARB after PCI with DES in STEMI patients.

P5362Impact of statin therapy on long-term clinical outcomes between STEMI and NSTEMI after stent implantation

Background

Although European guideline recommends that statin should be given to all patients with acute myocardial infarction (AMI), irrespective of cholesterol concentration, limited studies were focused on the long-term effects of statin therapy between ST-segment elevation MI (STEMI) and non-ST-segment elevation MI (NSTEMI).

Purpose

The authors conducted the study to compare the relative beneficial role of statin on 2-year major clinical outcomes between STEMI and NSTEMI in patients who underwent successful PCI with DES.

Methods

Finally, a total of 26317 AMI patients who underwent stent implantation and who were prescribed the statin were enrolled and they were separated into two groups; the STEMI group (n=15002) and the NSTEMI group (n=11315). The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), total coronary revascularization (target lesion revascularization [TLR], target vessel revascularization [TVR], non-TVR) during 2-year follow-up period.

Results

After propensity score-matched (PSM) analysis, two PSM groups (7746 pairs, n=15492, C-statistic = 0.766) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, and cardiac death were significantly higher in the NSTEMI group. However, after PSM, the cumulative incidence of all-cause death (Hazard ratio, 1.386; 95% CI, 1.133–1.696; p=0.002) was significantly higher in the NSTEMI group. The cumulative incidences of MACE, cardiac death, re-MI, total revascularization, TLR, TVR, and non-TVR were similar between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value STEMI NSTEMI Log-rank Propensity score matched patients MACE 532 (7.2) 584 (8.1) 0.092 1.106 (0.984–1.244) 0.092 All-cause death 163 (2.2) 224 (3.1) 0.001 1.386 (1.133–1.696) 0.002 Cardiac death 121 (1.5) 148 (2.0) 0.088 1.232 (0.969–1.566) 0.089 Re-MI 117 (1.6) 107 (1.5) 0.545 0.922 (0.710–1.199) 0.545 Total revascularization 291 (4.1) 307 (4.4) 0.422 1.068 (0.910–1.254) 0.423 TLR 92 (1.3) 89 (1.2) 0.880 0.978 (0.731–1.309) 0.880 TVR 173 (2.4) 184 (2.6) 0.478 1.078 (0.876–1.327) 0.478 Non-TVR 123 (1.7) 130 (1.9) 0.593 1.070 (0.836–1.369) 0.539

Conclusion

The mortality reduction capability of statin was more prominent in the STEMI group compared with the NSTEMI group.

P5494Impact of the gender difference on long-term clinical outcomes in dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES

Background

There are limited comparative data concerning long-term major clinical outcomes between male and female in dyslipidemic AMI patients after PCI with new-generation DES.

Purpose

We thought to investigate the impact of gender difference on the 2-year clinical outcomes.

Methods

Finally, a total of 2403 eligible dyslipidemic AMI patients who underwent PCI with new-generation DES were enrolled and they were separated into two groups; the male group (n=1800) and the female group (n=603). The primary endpoint was major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), and target vessel revascularization (TVR). The secondary endpoints were the incidence of the individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR

Results

Two propensity score-matched (PSM) groups (422 pairs, n=844, C-statistic = 0.850) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, re-MI, and TVF were significantly higher in the female group compared with the male group. However, after propensity score-matched (PSM) analysis, the cumulative incidences of MACE (HR, 0.971; 95% CI, 0.628–1.501; p=0.895), all-cause death (HR, 1.061; 95% CI, 0.536–2.100; p=0.865), re-MI (HR, 1.212; 95% CI, 0.433–2.907; p=0.813), and TVF (HR, 0.764; 95% CI, 0.474–1.229; p=0.267) were similar between the two groups. In addition, the cumulative incidences of cardiac death, TLR, TVR were not significantly different between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Male Female Log-rank Propensity score matched patients MACE 41 (10.4) 40 (10.3) 0.895 0.971 (0.628–1.501) 0.895 All-cause death 16 (4.0) 17 (4.2) 0.865 1.061 (0.536–2.100) 0.865 Cardiac death 13 (3.3) 9 (2.2) 0.391 0.691 (0.295–1.616) 0.393 Re-MI 8 (2.0) 9 (2.4) 0.813 1.212 (0.433–2.907) 0.813 TLR 7 (1.8) 6 (1.6) 0.781 0.857 (0.298–2.550) 0.781 TVR 16 (4.3) 10 (2.7) 0.236 0.623 (0.283–1.373) 0.241 TVF 39 (10.2) 30 (7.8) 0.265 0.764 (0.474–1.229) 0.267

Conclusion

The gender difference was not apparent in these dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES during 2-year follow-up period.

Hypoxia improves hair inductivity of dermal papilla cells via nuclear NADPH oxidase 4-mediated reactive oxygen species generation'

BACKGROUND

Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis. Therefore, tremendous efforts have been made to promote DPC hair inductivity.

OBJECTIVES

The aim of this study was to investigate the mitogenic and hair inductive effects of hypoxia on DPCs and examine the underlying mechanism of hypoxia-induced stimulation of DPCs.

METHODS

DPCs' hair inductivity was examined under normoxia (20% O₂ ) and hypoxia (2% O₂ ).

RESULTS

Hypoxia significantly increased the proliferation and delayed senescence of DPCs via Akt phosphorylation and downstream pathways. Hypoxia upregulated growth factor secretion of DPCs through the mitogen-activated protein kinase pathway. Hypoxia-preconditioned DPCs induced the telogen-to-anagen transition in C₃ H mice, and also enhanced hair neogenesis in a hair reconstitution assay. Injected green fluorescent protein-labelled DPCs migrated to the outer root sheath of the hair follicle, and hypoxia-preconditioning increased survival and migration of DPCs in vivo. Conditioned medium obtained from hypoxia increased the hair length of mouse vibrissa follicles via upregulation of alkaline phosphatase, vascular endothelial growth factor, and glial cell line-derived neurotrophic factor. We examined the mechanism of this hypoxia-induced stimulation, and found that reactive oxygen species (ROS) play a key role. For example, inhibition of ROS generation by N-acetylcysteine or diphenyleneiodonium treatment attenuated DPCs' hypoxia-induced stimulation, but treatment with ROS donors induced mitogenic effects and anagen transition. NADPH oxidase 4 is highly expressed in the DPC nuclear region, and NOX4 knockout by CRISPR-Cas9 attenuated the hypoxia-induced stimulation of DPCs.

CONCLUSIONS

Our results suggest that DPC culture under hypoxia has great advantages over normoxia, and is a novel solution for producing DPCs for cell therapy. What's already known about this topic? Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis, but they are difficult to isolate and expand for use in cell therapy. Tremendous efforts have been made to increase proliferation of DPCs and promote their hair formation ability. What does this study add? Hypoxia (2% O₂ ) culture of DPCs increases proliferation, delays senescence and enhances hair inductivity of DPCs. Reactive oxygen species play a key role in hypoxia-induced stimulation of DPC. What is the translational message? Preconditioning DPCs under hypoxia improves their hair regenerative potential, and is a novel solution for producing DPCs for cell therapy to treat hair loss.

Synthesis and Electroresponse Activity of Porous Polypyrrole/Silica-Titania Core/Shell Nanoparticles

Inverted conducting polymer/metal oxide core/shell structured pPPy/SiO₂-TiO₂ nanoparticles were prepared as electrorheological (ER) materials using sequential experimental methods. The core was synthesized via the low-temperature self-assembly of PPy and SiO₂ materials, and the outer TiO₂ shell was easily coated onto the core part using a sol-gel method and a titanium isopropoxide precursor. Sonication-mediated etching and redeposition were employed to etch out SiO₂ portions from the core part to blend with TiO₂ shells. Each step in nanoparticle synthesis involved morphological and physical changes to the surface area and porosity, with subsequent changes in the intrinsic properties of the materials. Specifically, the electrical conductivity and dielectric properties were successfully altered. The final pPPy/SiO₂-TiO₂ nanoparticle configuration was optimized for ER applications, offering low electrical conductivity, high dielectric properties, and increased dispersion stability. pPPy/SiO₂-TiO₂ nanoparticles exhibited 24.7- and 2.7-fold enhancements in ER performance compared to that of PPy-SiO₂ and PPy-SiO₂/TiO₂ precursor nanoparticles, respectively. The versatile method proposed in this study for the synthesis of inverted conducting polymer/metal oxide core/shell nanoparticles shows great potential for the development of custom-designed ER materials.

Associations of a social network typology with physical and mental health risks among older adults in South Korea

OBJECTIVES

The objectives of this study were to (1) develop an empirical typology of social networks in older Koreans; and (2) examine its effect on physical and mental health.

METHOD

A sample of 6900 community-dwelling older adults in South Korea was drawn from the 2014 Korean National Elderly Survey. Latent profile analysis (LPA) was conducted to derive social network types using eight common social network characteristics (marital status, living arrangement, the number and frequency of contact with close family/relatives, the number and frequency of contact with close friends, frequency of participation in social activities, and frequency of having visitors at home). The identified typologies were then regressed on self-rated health and depressive symptoms to explore the health risks posed by the group membership.

RESULTS

The LPA identified a model with five types of social network as being most optimal (BIC = 153,848.34, entropy = .90). The groups were named diverse/family (enriched networks with more engagement with family), diverse/friend (enriched networks with more engagement with friends), friend-focused (high engagement with friends), distant (structurally disengaged), and restricted (structurally engaged but disengaged in family/friends networks). A series of regression analyses showed that membership in the restricted type was associated with more health and mental health risks than all types of social networks except the distant type.

CONCLUSION

Findings demonstrate the importance of family and friends as a source of social network and call attention to not only structural but also non-structural aspects of social isolation. Findings and implications are discussed in cultural contexts.

Smart Fluid System Dually Responsive to Light and Electric Fields: An Electrophotorheological Fluid

Electrophotorheological (EPR) fluids, whose rheological activity is dually responsive to light and electric fields (E fields), is formulated by mixing photosensitive spiropyran-decorated silica (SP-sSiO₂) nanoparticles with zwitterionic lecithin and mineral oil. A reversible photorheological (PR) activity of the EPR fluid is developed via the binding and releasing mechanism of lecithin and merocyanine (MC, a photoisomerized form of SP) under ultraviolet (UV) and visible (VIS) light applications. Moreover, the EPR fluid exhibits an 8-fold higher electrorheological (ER) performance compared to the SP-sSiO₂ nanoparticle-based ER fluid (without lecithin) under an E field, which is attributed to the enhanced dielectric properties facilitated by the binding of the lecithin and SP molecules. Upon dual application of UV light and an E field, the EPR fluid exhibits high EPR performance (ca. 115.3 Pa) that far exceeds its separate PR (ca. 0.8 Pa) and ER (ca. 57.5 Pa) activities, because of the synergistic contributions of the PR and ER effects through rigid and fully connected fibril-like structures. Consequently, this study offers a strategy on formulation of dual-stimuli responsive smart fluid systems.

Enhanced Electrorheological Performance of Mixed Silica Nanomaterial Geometry

The mixed geometrical effect on the electrorheological (ER) activity of bimodal ER fluids was investigated by mixing SiO₂ spheres and rods of different dimensions. To gain an in-depth understanding of the mixed geometrical effect, 12 bimodal ER fluids were prepared from 4 sizes of SiO₂ spheres (50, 100, 150, and 350 nm) and 3 types of SiO₂ rods with different aspect ratios (L/D = 2, 3, and 5). Five concentrations of SiO₂ spheres and rods were created for each bimodal ER fluid, resulting in a total of 60 sets of comprehensive ER measurements. Some bimodal ER fluids exhibited enhanced ER performance, as high as 23.0%, compared to single SiO₂ rod-based ER fluids to reveal the mixed geometrical effect of bimodal ER fluids. This interesting experimental result is based on the structural reinforcement provided by spheres to fibrillated rod materials, demonstrating the mixed geometrical effect on ER activity.

Fabrication of a silica/titania hollow nanorod and its electroresponsive activity

In this study, a 1D oriented hollow SiO₂/TiO₂ (HST) rod-like material was successfully fabricated via a sequential combination of sol–gel use, TiO₂ incorporation, and a sonication-mediated etching and redeposition method.

Effect of Insufficient Light Exposure on Polymerization Kinetics of Conventional and Self-adhesive Dual-cure Resin Cements

Objectives: The purpose of this study was to investigate the influence of insufficient light exposure on the polymerization of conventional and self-adhesive dual-cure resin cements under ceramic restorations.

Methods: Two conventional dual-cure resin cements (Rely-X ARC, Duolink) and two self-adhesive resin cements (Rely-X U200, Maxcem Elite) were polymerized under different curing modes (dual-cure or self-cure), curing times (20 and 120 seconds), and thickness of a ceramic overlay (2 and 4 mm). Polymerization kinetics was measured by Fourier transform infrared spectroscopy for the initial 10 minutes and after 24 hours. Data were analyzed using mixed model analysis of variance (ANOVA), one-way ANOVA/Student-Newman-Keuls post hoc test, and paired t-test (α=0.05).

Results: When light-curing time was set to 20 seconds, the presence of the ceramic block significantly affected the degree of conversion (DC) of all resin cements. Especially, the DC of the groups with 20 seconds of light-curing time under 4 mm of ceramic thickness was even lower than that of the self-cured groups at 24 hours after polymerization (p&lt;0.05). However, when light-curing time was set to 120 seconds, a similar DC compared with the group with direct light exposure (p&gt;0.05) was achieved in all dual-cure groups except Maxcem Elite, at 24 hours after polymerization.

Conclusions: For both conventional and self-adhesive dual-cure resin cements, insufficient light exposure (20 seconds of light-curing time) through thick ceramic restoration (4 mm thick) resulted in a DC even lower than that of self-curing alone.

Distribution of Porcine Endogenous Retrovirus in Different Organs of the Hybrid of a Landrace and a Jeju Domestic Pig in Korea

Xenotransplantation offers a solution to the shortage of available organs for transplantation, and the pig represents an ideal source of such organs. However, porcine endogenous retrovirus (PERV), whose genome is integrated in pigs, has been suggested to pose a potential risk of xenotransmission. Expression of PERVs in different organs of pigs was carefully measured at DNA, mRNA, and protein levels, providing information valuable for the application of pig organs in xenotransplantation. An analysis of PERV DNA showed that a very similar number of PERV copies was present in the genome of all organs, whereas mRNA and protein levels of PERV varied depending on the organ, with kidney, liver, and spleen expressing high levels of both mRNA and protein. In contrast, mRNA and protein levels were dissimilar in the lung and brain, where mRNA levels were low but protein levels were high. This discrepancy indicates that mRNA levels are not always reflected in protein expression. In addition, the difference between mRNA and protein highlights the importance of choosing the proper analysis method for diagnosing viral infection. In summary, this study provides insight into the distribution of PERV in various organs at the DNA, mRNA, and protein levels, and also informs the proper selection of tissues or organs for future clinical xenotransplantation.

Effects of Palm Kernel Expellers on Productive Performance, Nutrient Digestibility, and White Blood Cells of Lactating Sows

This experiment was conducted to investigate the effects of palm kernel expellers on productive performance, nutrient digestibility, and changes in white blood cells (WBC) of lactating sows. A total of 14 sows (200±12 kg of average body weight [BW]; 2.5 of average parity) were used and moved from gestation room to farrowing room on d 109 of gestation. Sows were randomly assigned to 2 dietary treatments in a completely randomized design. The treatments were a diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Sows were fed the treatments for 28 days (weaning) after farrowing. Blood was collected from each sow and 4 randomly selected piglets from each sow before farrowing or on d 3, 7, or 14 of lactation. Sows were fed respective treatments containing 0.2% chromic oxide from d 15 to 21 of lactation. Fecal samples were collected daily for the last 3 days after the 4-d adjustment period. Measurements were performances and WBC changes of sows and litter, nutrient digestibility of sows, and daily diarrhea of litter. Sows fed PKE had greater average daily feed intake (7.38 vs 7.10 kg/d; p<0.05) and lost less BW (−6.85 vs −8.54 kg; p<0.05) and backfat depth (−0.42 vs −0.71 mm; p<0.05) than those fed CON. However, there were no differences on digestibility of dry matter, nitrogen, and energy and weaning to estrus interval of sows fed either CON or PKE. Piglets from sows fed PKE gained more BW (203 vs 181 g/d; p = 0.08) and had less frequency of diarrhea (6.80 vs 8.56%; p = 0.07) than those from sows fed CON. On the other hand, no difference was found on preweaning mortality of piglets from sows fed either CON or PKE. Sows fed PKE had lower number of WBC (9.57 vs 11.82 ×10³/μL; p = 0.09) before farrowing than those fed CON, but no difference on d 3 and 7. Similarly, piglets from sows fed PKE had also lower number of WBC (7.86 vs 9.80 ×10³/μL; p<0.05) on d 14 of lactation than those from sows fed CON, but no difference on d 3 and 7. In conclusion, addition of 20% palm kernel expellers to lactation diet based on corn and soybean meal had no negative effects on productive performance, nutrient digestibility, and WBC changes of lactating sows.

Effects of Palm Kernel Expellers on Growth Performance, Nutrient Digestibility, and Blood Profiles of Weaned Pigs

This experiment was conducted to investigate the effects of palm kernel expellers on growth performance, nutrient digestibility, and blood profiles of weaned pigs. A total of 88 weaned pigs (6.94±0.76 kg body weight [BW]; 28 d old) were randomly allotted to 2 dietary treatments (4 pigs/pen; 11 replicates/treatment) in a randomized complete block design (sex as a block). The dietary treatments were a typical nursery diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Pigs were fed for 6 wk using a 3-phase feeding program with declining diet complexity and with phases of 1, 2, and 3 wk, respectively. Blood was collected from randomly selected 2 pigs in each pen before weaning and on d 7 after weaning. Pigs were fed respective dietary treatments containing 0.2% chromic oxide from d 29 to 35 after weaning. Fecal samples were collected from randomly selected 2 pigs in each pen daily for the last 3 days after the 4-d adjustment period. Measurements were growth performances, digestibility of dry matter, nitrogen and energy, white and red blood cell counts, packed cell volume, and incidence of diarrhea. The PKE increased average daily gain (ADG) (246 vs 215 g/d; p = 0.06) and average daily feed intake (ADFI) (470 vs 343 g/d; p<0.05) and decreased gain-to-feed ratio (G:F) (0.522 vs 0.628 g/g; p<0.05) during phase 2 compared with CON, but did not affect growth performance during phase 1 and 3. During overall experimental period, PKE increased ADG (383 vs 362 g/d; p = 0.05) and ADFI (549 vs 496 g/d; p<0.05) compared with CON, but did not affect G:F. However, no differences were found on digestibility of dry matter, nitrogen, and energy between CON and PKE. The PKE reduced frequency of diarrhea (15% vs 25%; p = 0.08) for the first 2 wk after weaning compared with CON. Similarly, PKE decreased white blood cells (8.19 vs 9.56×10(3)/μL; p = 0.07), red blood cells (2.92 vs 3.25×10(6)/μL; p = 0.09), and packed cell volume (11.1% vs 12.6%; p = 0.06) on d 7 after weaning compared with CON. In conclusion, addition of 20% palm kernel expellers to nursery diet based on corn and soybean meal had no negative effects on growth performance, nutrient digestibility, and blood profiles of weaned pigs.

Highly fluorescent amidine/schiff base dual-modified polyacrylonitrile nanoparticles for selective and sensitive detection of copper ions in living cells

Highly fluorescent surface modified polyacrylonitrile nanoparticles (PAN NPs) of 50 nm diameter were fabricated for selective Cu(2+) sensing. After surface modification, the PAN NPs were converted to amidine/Schiff base dual-modified PAN nanoparticles (tPAN NPs) with a Cu(2+) sensing property and high QY (0.19). The selectivity of tPAN NPs for Cu(2+) is much higher than that of other metal ions due to the fact that amidine group on the surface of tPAN NPs has a higher binding affinity with Cu(2+). The effect of other metal ions on the fluorescence intensity of the tPAN NPs was also studied, and other metal ions showed a low interference response in the detection of Cu(2+). Furthermore, as a metal ion chelator, ethylenediaminetetraacetate can competitively interact with Cu(2+) to recover the quenched fluorescence of tPAN NPs. The tPAN NPs are easily introduced into cells and exhibit low toxicity, enabling their use as a fluorescence sensor for Cu(2+) in living cells. The tPAN NPs provide a new direction for the development of copper ion sensors in living cells.

γ-Secretase inhibition promotes fibrotic effects of albumin in proximal tubular epithelial cells

BACKGROUND AND PURPOSE

Albuminuria is an important biomarker of renal dysfunction and is a major mediator of renal damage and fibrosis during kidney disease. The mechanisms underlying albumin-induced renal fibrosis remain unclear. There has been significant interest in γ-secretase activity in tubular epithelial cells in recent times; however, its potential role in albumin-induced fibrosis has not been investigated.

EXPERIMENTAL APPROACH

The primary aim of this study was to examine the role of γ-secretase in albumin-induced fibrotic effects in proximal tubular cells. The effects of increasing albumin concentrations on fibrosis indicators and mediators in the human HK-2 cell line were examined in the presence and absence of a γ-secretase inhibitor, compound E.

KEY RESULTS

Treatment with albumin resulted in a number of pro-fibrotic effects, including up-regulation of fibronectin, TGF-β1 and the EGF-R. Interestingly, similar effects were observed in response to treatment with the γ-secretase inhibitor, compound E. Co-treatment of cells with albumin and an EGF-R inhibitor, AG-1478, resulted in significant inhibition of the observed pro-fibrotic effects, suggesting a major role for the EGF-R in albumin-induced fibrotic events. Albumin-induced effects on the EGF-R appeared to be mediated through inhibition of γ-secretase activity and were dependent on ERK-MAPK signalling.

CONCLUSIONS AND IMPLICATIONS

These results provide novel insights into the mechanisms of albumin-induced fibrotic effects in tubular epithelial cells, suggesting important roles for the γ-secretase and the EGF-R. These results suggest that the proposed use of γ-secretase inhibitors as anti-fibrotic agents requires further investigation.

Fabrication of barium- and strontium-doped silica/titania hollow nanoparticles and their synergetic effects on promoting neuronal differentiation by activating ERK and p38 pathways

Pristine, barium-doped, and strontium-doped hollow nanoparticles (p-HNPs, Ba-HNP, and Sr-HNP; HNPs) are prepared by sonication-mediated etching and redeposition (SMER) method and alkali-earth-metal hydroxide solution treatment. The HNPs are investigated to facilitate synergetic neuronal differentiation through alkali-earth-metal doping and in conjunction with nerve growth factor (NGF). PC12 cells are used as model cells for neuronal differentiation. The differentiation efficiency is improved in the presence of the HNPs+NGF, and the neurite length is in the order of Sr-HNP+NGF > Ba-HNP+NGF > p-HNP+NGF > NGF. Silica/titania have increasing effect on both differentiation efficiency and neurite length, and doped barium/strontium influences additional elongation of the average neurite length. Take advantage of hollow structure, NGF is encapsulated into HNPs, and they are further applied for directly inducing differentiation. The maximum differentiation efficiency is 67% in presence of the NGF-encapsulated Sr-HNP, which was 1.3 times higher than previous research. Furthermore, the neurite length is also 2.7 times higher than MnO2 decorated poly(3,4-ethylenedioxythiophene) nanoellipsoids. Ba- and Sr-HNP may offer a possibility for novel application of metal-hybrid nanomaterials for cell differentiation, and can be expanded to other cellular applications.