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To evaluate and compare push-out bond strength of glass-fiber posts according to the type of endodontic sealers and the timing of post cementation. Fifty-four extracted single-rooted human mandibular premolars were included, and root canal instrumentation was done in a chemo-mechanical way. The teeth were randomly divided into three groups (n=18) according to the endodontic sealers used for root canal obturation: group A – AH Plus [Dentsply DeTrey, Konstanz, Germany], group C – Ceraseal [Metabiomed, Cheongju, Korea] group E – Endoseal [Maruchi, Wonju, Korea]. Each group was subdivided into 2 subgroups (n=9) based on the timing of post cementation: subgroup 1 – immediately after root canal obturation, subgroup 2 – 48 hours after root canal obturation. After the post cementation, disc samples with 2 mm thickness were taken from the middle of the root and subjected to a push-out bond strength test. The samples were also examined under a stereomicroscope and scanning electron microscope to observe the sectioned surface and failure mode. Data were analyzed using one-way ANOVA followed by the Bonferroni test and independent T-test. This work was supported by the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, the Ministry of Food and Drug Safety) (Project Number: 202015×16, KMDF_PR_20200901_0288) (NTIS, KMDF-RnD 1711138930) When the posts were cemented immediately after root canal obturation, there was a significant difference between group A-1(19.5±3.4 MPa) and group C-1(12.1±3.6 MPa), and between group A-1 and group E-1(10.6±6.1 MPa) (p0.05). In the AH-plus group, subgroup 1 demonstrated significantly higher bond strength than subgroup 2 (p0.05). Epoxy-resin based sealer showed significantly higher bond strength than calcium-silicate based sealer when the fiber post was cemented immediately after root canal obturation. There was no significant difference among all groups when the post was cemented 48 hours after root canal obturation. The most common failure mode was adhesive failure between dentin and resin cement. [ABSTRACT FROM AUTHOR]

Results indicate that the response of TRP channel to signals is dependent on the physical association between TRPC1 and the calcium channel IP(sub)3R, facilitated by the adaptor protein termed Homer. Data show that disassembly of the TRPC1-Homer-calcium channel complex is analogous to TRPC1 activation.

Primary somatosensory axons stop regenerating as they re-enter the spinal cord, resulting in incurable sensory loss. What arrests them has remained unclear. We previously showed that axons stop by forming synaptic contacts with unknown non-neuronal cells. Here, we identified these cells in adult mice as oligodendrocyte precursor cells (OPCs). We also found that only a few axons stop regenerating by forming dystrophic endings, exclusively at the CNS:peripheral nervous system (PNS) borderline where OPCs are absent. Most axons stop in contact with a dense network of OPC processes. Live imaging, immuno-electron microscopy (immuno-EM), and OPC-dorsal root ganglia (DRG) co-culture additionally suggest that axons are rapidly immobilized by forming synapses with OPCs. Genetic OPC ablation enables many axons to continue regenerating deep into the spinal cord. We propose that sensory axons stop regenerating by encountering OPCs that induce presynaptic differentiation. Our findings identify OPCs as a major regenerative barrier that prevents intraspinal restoration of sensory circuits following spinal root injury. [Display omitted] • Axons occasionally stop by forming dystrophic endings at the CNS:PNS borderline • Most axons cross the borderline and then stop in association with OPCs at the DREZ • DRG axons form synapses with OPCs at the DREZ and in vitro • OPC ablation enables continued axon regeneration at and beyond the DREZ Kim et al. identify oligodendrocyte precursor cells (OPCs) as the postsynaptic cells arresting sensory axons regenerating into the spinal cord at the CNS:PNS interface, the DREZ. Synaptogenic arrest by OPCs may play a decisive role in inhibiting axon regeneration at the DREZ and elsewhere in the CNS. [ABSTRACT FROM AUTHOR]

The yielding metallic devices have been used to improve the performance of building structures at design level intensities. They dissipate large levels of vibration energy through yielding of disposable steel plate elements but they may also enhance acceleration response related damage of mechanical and electrical components. This paper addresses the optimal design of these devices that minimizes the expected life-cycle object cost considering the story drift and acceleration related damages over the entire spectrum of seismic intensities that can occur on a building site. Genetic algorithm is used to calculate the optimal design parameters of the devices. The uncertainties associated with the frequency of occurrence of earthquakes of different intensities and random characteristics of the structural response are included in the life-cycle failure cost and the object cost calculations. It shown that these devices can be used effectively to reduce the overall life-cycle object cost and can be considered as good protective investment for structural designs in seismic regions. [ABSTRACT FROM AUTHOR]

Porous polyethylene (PPE) implants are biocompatible alloplastic materials commonly used for facial augmentation. However, the effect of sub-periosteal PPE application on the surrounding tissues has not been analyzed clearly. This report documents the case of a 22-year-old woman who underwent peri-alar augmentation with PPE to improve midface retrusion. Although no infection or inflammation occurred at the surgical site, the patient requested removal of the PPE implant for aesthetic reasons alone at 1 year after the surgery. The removed implant was subjected to histological and morphological evaluation using conventional histological staining and scanning electron microscopy (SEM). Histopathological staining revealed bone ingrowth into the pores of the implant near the boundary with the host bone. Little evidence of a foreign body reaction was observed. SEM revealed densely arranged collagen fibres and osteoblastic cells in the pores. Moreover, the outer surface of the PPE implant in contact with the periosteum showed fibrous tissue ingrowth, leading to tissue adhesion. These findings confirm bone ingrowth into the PPE pore structure in humans. [ABSTRACT FROM AUTHOR]

This experiment was conducted to investigate the effect of feeding duration of diets containing corn distillers dried grains with solubles (DDGS) on productive performance, egg quality, and lutein and zeaxanthin concentrations of egg yolk in laying hens. A total of 300 57-week-old Hy-Line Brown laying hens were randomly assigned to one of 5 treatment groups (feeding duration) with 6 replicates consisting of 5 consecutive cages with 2 hens per cage. Diets were formulated to contain either 0% (the control diet) or 20% DDGS. Experimental diets were fed to hens for 12 wk. The feeding duration of diets containing 20% DDGS was 0, 3, 6, 9, or 12 wk before the conclusion of the experiment. Feeding the diet containing 20% DDGS for 3, 6, or 9 wk followed feeding the control diet for 9, 6, or 3 wk, respectively. The data for productive performance were summarized for 12 wk of the feeding trial. Results indicated that increasing feeding duration of diets containing 20% DDGS had no effects on productive performance of laying hens, but increased egg yolk color (linear, P < 0.01), hunter a* value (linear and quadratic, P < 0.01), and b* values (linear, P < 0.05) with a decrease in hunter L* value (linear and quadratic, P < 0.05). Lutein and zeaxanthin concentrations of egg yolks also were increased (linear, P < 0.01) by increasing the feeding duration of diets containing 20% DDGS. In conclusion, feeding diets containing 20% DDGS to laying hens has no adverse effects on productive performance. Increasing the feeding duration of diets containing 20% DDGS improves egg yolk coloration with a concomitant increase in lutein and zeaxanthin concentrations of egg yolks in laying hens. [ABSTRACT FROM AUTHOR]

Background: We evaluated the effect of magnesium sulphate on increased pain in 44 patients undergoing staged bilateral total knee arthroplasty (TKA).Methods: The magnesium group (n=22) and the control group (n=22) received magnesium sulphate and isotonic saline, respectively, throughout the surgery. Postoperative pain (visual analogue scale, VAS) at rest and the amounts of patient-controlled analgesia (PCA, fentanyl) and rescue analgesia (ketoprofen) administered during the first 48 h were compared between the two groups and within each group between the first and second TKA.Results: The VAS scores were significantly higher in the control group than in the magnesium group not only after the first TKA [29 (11) vs 19 (9) at 24 h and 33 (8) vs 24 (10) at 48 h; P=0.001] but also after the second TKA [44 (17) vs 20 (10) at 24 h and 43 (14) vs 25 (10) at 48 h; P<0.001]. In the control group, VAS scores were significantly higher for the second than for the first operated knee [44 (17) vs 29 (11) at 24 h and 43 (14) vs 33 (8) at 48 h; P<0.001 and P=0.006, respectively]. In the magnesium group, there were no significant differences in VAS scores between the first and second TKA. Magnesium significantly reduced the amounts of rescue analgesics and fentanyl administered over the first 48 h postoperatively.Conclusions: Magnesium sulphate administration significantly reduced postoperative pain and minimized the difference in pain intensity between the first and second operations.Clinical Trial Registration: KCT0001361. [ABSTRACT FROM AUTHOR]

Purpose Previously, we reported a nomogram for the prediction of positive resection margin (RM) after breast conserving surgery (BCS). This study was conducted to evaluate the clinical usefulness of the nomogram. Methods Prospective patients who underwent operations using the nomogram between July 2012 and August 2013 (nomogram group; N = 260) were compared with past control patients who underwent operations between July 2010 and October 2011 and underwent frozen section biopsy (FSB) without use of the nomogram (N = 266). In the nomogram group, an intraoperative assessment of RM using FSB was only performed when the nomogram score was higher than predefined cut-off (>80). In addition, we conducted retrospective analysis of additional 181 patients who received BCS in another institute (Kyoto University Hospital). These patients did not undergo FSBs for RMs. Results Of 260 patients, 161 (61.9%) presented low nomogram scores and avoided FSB. The surgical decision to use the nomogram did not significantly increase reoperation rate due to positive RM compared with the control FSB group (4.6% vs. 3.8%, p = 0.47). The surgery time was significantly reduced by 18.1% (mean 14.7 min) in nomogram group (p < 0.001). Of 99 nomogram high-score patients, 14 presented with positive RM on FSB and 11 of them avoided reoperation. In the Kyoto cohort, the reoperation rate was significantly lower in low-score patients than in high-score patients (2.7% vs. 11.4%, p < 0.001). Conclusions We showed that our nomogram is useful to reduce FSBs without increasing reoperation rate for surgeons who perform routine FSBs. For most surgeons, it can give useful information about the possibility of tumor-positive RMs. [ABSTRACT FROM AUTHOR]

One of the key enablers for the successful integration of 3-D interconnects using the Through-Silicon Via (TSV) schemes is the control of the mechanical stresses in the Cu TSV itself as well as in the surrounding silicon substrate. The synchrotron-sourced X-ray microdiffraction technique has been recognized to allow some important advantages compared to other techniques in characterization of the mechanical stresses in a TSV sample. This approach have been used to study Cu TSV samples from SK Hynix, Inc. earlier as well as more recently from SEMATECH, and we have found interesting differences in the stress states of the Cu TSV. We proposed a possible explanation of the observed differences. This fundamental understanding could lead to improved stress control and hence reliability in the Cu TSV samples, as well as to reduce its impact to the silicon electron mobility and hence to device performance in general. [ABSTRACT FROM AUTHOR]