▶ Treadmill exercise ameliorates cognitive deficits in Tg mice. ▶ Treadmill exercise reduces Aβ-42 and tau deposition in Tg mice. ▶ Treadmill exercise reduces the number of TUNEL-positive cells in Tg ...mice. ▶ Treadmill exercise reduces TC, insulin, glucose, and corticosterone levels in Tg mice. ▶ Treadmill exercise may be beneficial in prevention or treatment in AD.
The present study was undertaken to further investigate the protective effect of treadmill exercise on the hippocampal proteins associated with neuronal cell death in an aged transgenic (Tg) mice with Alzheimer's disease (AD). To address this, Tg mouse model of AD, Tg-NSE/PS2m, which expresses human mutant PS2 in the brain, was chosen. Animals were subjected to treadmill exercise for 12 weeks from 24 months of age. The exercised mice were treadmill run at speed of 12
m/min, 60
min/day, 5 days/week on a 0% gradient for 3 months. Treadmill exercised mice improved cognitive function in water maze test. Treadmill exercised mice significantly reduced the expression of Aβ-42, Cox-2, and caspase-3 in the hippocampus. In parallel, treadmill exercised Tg mice decreased the phosphorylation levels of JNK, p38MAPK and tau (Ser404, Ser202, Thr231), and increased the phosphorylation levels of ERK, PI3K, Akt and GSK-3α/β. In addition, treadmill exercised Tg mice up-regulated the expressions of NGF, BDNF and phospho-CREB, and the expressions of SOD-1, SOD-2 and HSP-70. Treadmill exercised Tg mice up-regulated the expression of Bcl-2, and down-regulated the expressions of cytochrome c and Bax in the hippocampus. The number of TUNEL-positive cells in the hippocampus in mice was significantly decreased after treadmill exercise. Finally, serum TC, insulin, glucose, and corticosterone levels were significantly decreased in the Tg mice after treadmill exercise. As a consequence of such change, Aβ-dependent neuronal cell death in the hippocampus of Tg mice was markedly suppressed following treadmill exercise. These results strongly suggest that treadmill exercise provides a therapeutic potential to inhibit both Aβ-42 and neuronal death pathways. Therefore, treadmill exercise may be beneficial in prevention or treatment of AD.
A biofilm, a community of microorganisms, is highly resistant to antibiotics, resulting in massive losses in various areas. We herein present a strategy to remove Streptococcus mutans biofilms ...through a spontaneous exfoliation by the synergistic effect between zwitterion and sugar alcohols. It is assumed that the anionic site of zwitterion can be coupled with sugar alcohols and the cationic site remains in the state of lacking electrons. The cationic site allows the complexes to be delivered to negatively charged exopolysaccharides of biofilms. This strategy facilitates a significant increase in the ability of sugar alcohols to disperse aggregated exopolysaccharides. In this work, it was demonstrated that the mixture of betaine and erythritol existed as a complex in water and that the complex induced a spontaneous detachment of biofilms from the surface to which the biofilms had been adhered. This detachment resulted from a reduction in adhesive forces of the biofilms due to an increase in solubility of bacterial exopolysaccharides. The effects triggered by the formation of complex between zwitterion and sugar alcohol provide a simple and safe way to remove biofilms without antibiotics and physical forces.
•We provide lots of test data for magnesium potassium phosphate composites (MKPC).•We found that the molar ratio of MgO-KH2PO4 for the highest strength depends on W/B.•For practical application of ...MKPC, adequate molar ratio and W/B are recommended.•Compressive strength development of MKPC mortars is formulated.
The objective of the present study is to examine the effect of the water-to-binder ratio (W/B) and the molar ratio (Mmp) of magnesium-to-phosphate on the fluid characteristics, compressive strength development, and pH variation of magnesium potassium phosphate composite (MKPC) mortars. A total of 25 mortar mixes were prepared, with the W/B varying from 20% to 40% and Mmp varying from 3.4 to 30.4. Using the present test data, the compressive strength development of MKPC mortars was empirically formulated, which reflects rapid strength gain. Considering practical qualifications, including a relatively good 28-day compressive strength above 30MPa, delayed setting time, and a near-neutral pH not exceeding 9.4, it can be recommended that the Mmp and W/B be chosen to be below 5.1 and above 25%, respectively, in the MKPC system. With a decrease in the Mmp value, the peak intensities for struvite-k increased slightly, whereas the peak intensities for unreacted MgO were considerably weakened as the Mmp value fell below 5.1. The total porosity of the MKPC pastes was governed by the macro-capillary pores, implying that the 28-day compressive strength is inversely proportional to the macro-capillaries.
PURPOSEThe purpose of this study was to compare the surface roughness, phase transformation, and surface topography of dental zirconia with three different yttrium oxide compositions under same ...grinding and polishing conditions.MATERIALS AND METHODSThree zirconia disks (IPS e.max ZirCAD LT, MT, MT multi, Ivoclar Vivadent AG, Schaan, Liechtenstein) were selected for experimental materials. Sixty-nine bar-shaped specimens were fabricated as 12.0 × 6.0 × 4.0 mm using a milling machine and glazing was conducted on 12.0 × 6.0 mm surface by same operator. With a custom polishing device, 12.0 × 6.0 mm surfaces were polished under same condition. Surface roughness (Raµm) was measured before grinding (C), after grinding (G), and at every 3 steps of polishing (P1, P2, P3). X-ray diffraction and FE-SEM observation was conducted before grinding, after grinding, and after fine polishing (P3). Statistical analysis of surface roughness was performed using Kruskal-Wallis test and Mann-Whitney-U test was used as a post hoc test (α = .05).RESULTSThere were no significant differences of surface roughness between LT, MT, and MM groups. In LT, MT, and MM groups, P3 groups showed significantly lower surface roughness than C groups. X-ray diffraction showed grinding and polishing didn't lead to phase transformation on zirconia surface. In FE-SEM images, growths in grain size of zirconia were observed as yttrium oxide composition increases.CONCLUSIONPolished zirconia surface showed clinically acceptable surface roughness, but difference in yttrium oxide composition had no significant influence on the surface roughness. Therefore, in clinical situation, zirconia polishing burs could be used regardless of yttrium oxide composition.
•A conceptually new biological coating mortar was developed for concrete durability.•The glycocalyx membrane by photosynthetic bacteria was used for coating approach.•The bacterial immobilization ...technique was originally developed.•We examined the optimum growth environments of bacteria in hardened mortar.•We verified the potential of the developed coating mortar as a biomimetic material.
The effectiveness of biological coating mortars was examined by testing the variations of the compressive strength and mass of concrete and the transition of hydration products of the cement matrix in 5% sulfuric acid solutions. These biological coating mortars were originally developed in the previous investigation for enhancing the sulfate resistance of concrete. Based on the block membrane action of the glycocalyx generated from bacterial activity, Rhodobacter capsulatus was isolated and immobilized in expanded vermiculite together with a bacterial medium. Concrete cylinders were coated with a thickness of 2.5 mm using three types of mortar: conventional mortar C without bacteria and bacterial agents, mortar B with non-immobilized bacteria, and mortar I with bacteria immobilized in accordance with the proposed technique. The glycocalyx formation and the survival of bacteria in the coating mortars immersed in sulfuric acid solutions were traced by scanning electron microscopy image and the viable cell count method. Test results revealed that the proposed biological coating technique is significantly favorable for restricting the decrease in the compressive strength of concrete exposed to sulfuric acid solution, with no delamination or cracks in the concrete. Moreover, the concrete specimen I under sulfuric acid solutions exhibited very close profiles for X-ray diffraction and thermogravimetric analysis to those of virgin concrete cured under the conventional environment. There were less gypsum and ettringite from the reaction between the hydration products of cement and sulfuric acid. Overall, the proposed biological coating technique facilitates biomimetic activity, even in a strong sulfuric acid environment.
This study investigated the effectiveness and limitations of newly developed biological mortars regarding chloride ion diffusion resistance. Through several tests on the glycocalyx production ...capacity and growth potentials of bacteria cells under marine environments,
Bacillus licheniformis
was isolated and immobilized in the expanded vermiculites together with a bacterial culture medium for producing biological mortars. The chloride ion diffusion coefficient of the mortars up to 91 days was determined through natural diffusion cell tests. Subsequently, the service life of RC structure repaired with biological mortars under chloride attack was evaluated considering multilayer theory and time-dependent diffusion. The addition of expanded vermiculites immobilizing
Bacillus licheniformis
significantly reduced the chloride ion diffusion coefficient. When its addition increased from 10 to 30%, the chloride ion diffusion coefficient decreased by 50–90% compared to that of mortars without bacteria. The service life of reinforced concrete structures repaired with biological mortars containing 30% expanded vermiculite concentration and thickness of 50 mm was evaluated to be six times longer than that of repaired with conventional mortar. Overall, this novel approach holds significant potential in addressing the salt-induced deterioration challenges faced by RC structures.
Since a concrete structure exposed to a sulfate environment is subject to surface ion ingress that yields cracking due to concrete swelling, its service life evaluation with an engineering modeling ...is very important. In this paper, cementitious repair materials containing bacteria, Rhodobacter capsulatus, and porous spores for immobilization were developed, and the service life of RC (Reinforced Concrete) structures with a developed bacteria-coating was evaluated through deterministic and probabilistic methods. Design parameters such protective coating thickness, diffusion coefficient, surface roughness, and exterior sulfate ion concentration were considered, and the service life was evaluated with the changing mean and coefficient of variation (COV) of each factor. From service life evaluation, more conservative results were evaluated with the probabilistic method than the deterministic method, and as a result of the analysis, coating thickness and surface roughness were derived as key design parameters for ensuring service life. In an environment exposed to an exterior sulfate concentration of 200 ppm, using the deterministic method, the service life was 17.3 years without repair, 19.7 years with normal repair mortar, and 29.6 years with the application of bacteria-coating. Additionally, when the probabilistic method is applied in the same environment, the service life was changed to 9.2–16.0 years, 10.5–18.2 years, and 15.4–27.4 years, respectively, depending on the variation of design parameters. The developed bacteria-coating technique showed a 1.47–1.50 times higher service life than the application of normal repair mortar, and the effect was much improved when it had a low COV of around 0.1.
Background:
Recurrent shoulder instability occurs more frequently after soft tissue surgery when the glenoid defect is greater than 20%. However, for lesions less than 20%, no scientific guidance is ...available regarding what size of bone fragments may affect shoulder functional restoration after bone incorporation.
Purpose/Hypothesis:
The purpose was to analyze how preoperative glenoid defect size and bone fragment incorporation alter postoperative clinical outcomes, we compared the functional outcomes of shoulders with and without bony Bankart lesion. It was hypothesized that differences in postoperative clinical outcomes between patients with and without bony fragments would be found only in patients with a larger glenoid defect.
Study Design:
Cohort study; Level of evidence, 3.
Methods:
A total of 223 patients who underwent arthroscopic stabilization surgery for recurrent anterior shoulder instability were divided into two groups based on the presence of anterior glenoid bone fragments. In each group, postoperative shoulder functional outcomes, sports activity level, and recurrence rates were evaluated according to preoperative glenoid defect size (small, <10%; medium, 10%-15% and 15%-20%; large, >20%).
Results:
In patients with small or medium defects, no significant differences were found in postoperative clinical outcomes and sports activity levels between the two groups. However, in patients with a large defect, the patients with bone fragments (mean ± SD American Shoulder and Elbow Surgeons ASES score, 92.3 ± 2.7; Rowe score, 90.9 ± 5.4) showed significantly superior clinical outcomes compared with patients who did not have fragments (ASES score, 87.3 ± 6.2, P = .02; Rowe score, 84.8 ± 7.3, P = .04). Among patients without bone fragments, recurrence increased significantly with increasing preoperative glenoid defect size (recurrence rates: 0% in small defects, 7.4% in medium defects, 22.2% in large defects), whereas patients with bone fragments showed no tendency for increasing or decreasing recurrence rates (0% in small defects, 7.9% in medium defects, 5.9% in large defects).
Conclusion:
In the treatment of bony Bankart lesion, the effect of bone fragment incorporation was different according to preoperative glenoid defect size. In patients with preoperative glenoid defects less than 20% of the glenoid width, bone fragment incorporation after arthroscopic bony Bankart repair did not alter clinical outcomes, sports activity levels, or recurrence rates, whereas in patients with defects greater than 20% of the glenoid width, bone fragment incorporation improved clinical outcomes and recurrence rates.
Ruthenium-alkylidene initiated ring-opening metathesis polymerization has been realized under solid-state conditions by employing a mechanochemical ball milling method. This method promotes greenness ...and broadens the scope to include mechano-exclusive products. The carbene- and pyridine-based Grubbs 3
rd
-generation complex outperformed other catalysts and maintained similar mechanistic features of solution-phase reactions. High-speed ball milling provides sufficient mixing and energy to the solid reaction mixture, which is composed of an initiator and monomers, to minimize or eliminate the use of solvents. Therefore, the solubility and miscibility of monomers and Ru-initiators are not limiting factors in solid-state ball milling. A wide variety of solid monomers, including ionomers, fluorous monomers, and macromonomers, were successfully polymerized under ball milling conditions. Importantly, direct copolymerization of immiscible (ionic/hydrophobic) monomers exemplifies the synthesis of mechano-exclusive polymers that are difficult to make using traditional solution procedures. Finally, the addition of a small amount of a liquid additive (
i.e.
, liquid-assisted grinding) minimized chain-degradation, enabling high-molecular-weight polymer synthesis.
Mechanochemical ball-milling ring-opening metathesis polymerization minimized solvent use and produced previously inaccessible polymers in solution.
•Valuable databank for the shrinkage strains of LWAC is provided.•Reliable design equations for shrinkage strains of LWAC are formulated.•We ascertained the internal curing effect on the long-term ...shrinkage of LWAC.•We confirmed that the code equations highly overestimated shrinkage strains of LWAC.
The objective of the present study is to provide a databank and comprehensible design equations for the shrinkage strain curve of lightweight aggregate concrete (LWAC) by using artificially expanded bottom ash and dredged soil granules. A total of 25 concrete mixtures were prepared with regard to the parameters of the substitution level of natural sand for lightweight fine aggregates and water-to-cement ratios. Based on the experimental observations, the time function, and 91-day shrinkage strain as a specific point were formulated by introducing the parameter of an equivalent porosity of aggregates to rationally evaluate the shrinkage strain curve of LWAC. Test results showed that the amount of shrinkage strain at 28 days ranged between 39% and 55% of that measured at 210 days, indicating that the acceleratory period was delayed due to the internal curing effect of lightweight aggregates. The shrinkage strains of LWAC decreased in proportion to the equivalent porosity (Peq) of aggregates, showing that the decreasing rates of the shrinkage strains ranged between 16% and 36% at 3 days, and 21% and 23% at 180 days when Peq value increased from 21.8% to 42.9%. For the proposed equations, the mean and standard deviation of the normalized root-mean-square error values between experiments and predictions are 0.44 and 0.21, respectively, resulting in a better accuracy than the code models (fib 2010 and EC 2) of which comparisons resulted in high overestimation, especially at an early age.
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