A modified repulsive bridge correction to accurate evaluation of solvation free energy in integral equation theory for molecular liquids

Integral equation theory for molecular liquids is one of the powerful frameworks to evaluate solvation free energy (SFE). Different from molecular simulation methods, the theory computes SFE in an analytical manner. In particular, the correction method proposed by Kovalenko and Hirata [Chem. Phys. Lett.290, 237 (Year: 1998);Kovalenko and Hirata J. Chem. Phys.113, 2793 (Year: 2000)]10.1063/1.1305885 is quite efficient in the accurate evaluation of SFE. However, the application has been limited to aqueous solution systems. In the present study, an improved method is proposed that is applicable to a wide range of solution systems. The SFE of a variety of solute molecules in chloroform and benzene solvents is evaluated. A key is the adequate treatment of excluded volume in SFE calculation. By utilizing the information of chemical bonds in the solvent molecule, the accurate computation of SFE is achieved

Phenotypic change of macrophages in the progression of diabetic nephropathy; sialoadhesin-positive activated macrophages are increased in diabetic kidney

Inflammatory process is involved in pathogenesis of diabetic nephropathy, although the activation and phenotypic change of macrophages in diabetic kidney has remained unclear. Sialoadhesin is a macrophage adhesion molecule containing 17 extracellular immunoglobulin-like domains, and is an I-type lectin which binds to sialic acid ligands expressed on hematopoietic cells. The aim of this study is to clarify the activation and phenotypic change of macrophages in the progression of diabetic nephropathy. We examined the expression of surface markers for pan-macrophages, resident macrophages, sialoadhesin, major histocompatibility complex class II and alpha-smooth muscle actin in the glomeruli of diabetic rats using immunohistochemistry at 0, 1, 4, 12, and 24 weeks after induction of diabetes by streptozotocin. Expression of type IV collagen and the change of mesangial matrix area were also measured. The mechanism for up-regulated expression of sialoadhesin on macrophages was evaluated in vitro. The number of macrophages was increased in diabetic glomeruli at 1 month after induction of diabetes and the increased number was maintained until 6 months. On the other hand, sialoadhesin-positive macrophages were increased during the late stage of diabetes concomitantly with the increase of alpha-smooth muscle actin-positive mesangial cells, mesangial matrix area and type IV collagen. Gene expression of sialoadhesin was induced by stimulation with interleukin (IL)-1 beta and tumor necrosis factor-alpha but not with IL-4, transforming growth factor-beta and high glucose in cultured human macrophages. The present findings suggest that sialoadhesin-positive macrophages may contribute to the progression of diabetic nephropathy

Intermittent administration of parathyroid hormone ameliorates periapical lesions in mice.

Intermittent administration of parathyroid hormone (PTH) promotes oral osseous wound healing and protects against ligature-induced alveolar bone loss. However, its therapeutic value on periapical periodontitis is unknown. The goal of this study was to determine the effect of intermittent PTH administration on the progression of periapical periodontitis.Seven lymphotoxin alpha-deficient mice received pulp exposures of mandibular first and second molars. Exposed pulp in the right mandible was covered with plaque-contaminated fibrin, whereas exposed pulp in the left mandible was left open. After 4 weeks, the periapical tissues were examined to determine the effect of plaque-contaminated fibrin to induce periapical lesions. Fourteen mice received pulp exposure covered with plaque-contaminated fibrin. PTH (40 μg/kg/d) was administered intermittently to half of the mice for 3 weeks beginning 1 week after pulp exposure. The remaining half received saline injections as the vehicle control. At sacrifice, mandibles and tibiae were harvested and processed for histologic examination. Evaluation of neutrophils and blood vessels was performed after staining with immunofluorescence, and periradicular bone was histomorphometrically analyzed.The exposed pulp covered with plaque-contaminated fibrin resulted in significantly larger periapical lesions compared with the control. Intermittent PTH administration reduced the size of periapical lesions significantly. Significantly less neutrophil infiltration around the root apex was found in PTH-treated animals compared with the control.PTH treatment suppressed periapical inflammation by reducing neutrophil infiltration and protected against tissue destruction by periapical periodontitis.福岡歯科大学2016年

The Effects of Implant Surface Characteristics on Surrounding Bone: A Comparative Study of Two Types of Surface Characteristics

The aims of this study were to create experimental implants by coating rough plastic surfaces with a thin layer of titanium, and to use the experimental implants in an animal experiment to investigate whether differences in the surface characteristics of the implant affect the peri-implant bone reaction during the period of osseointegration. Titanium rods of diameter 1.6 mm and length 7 mm were treated by acid etching (AE) or sandblasting followed by acid etching (SA), and replicas were made from plastic. Experimental implants were created by depositing a thin layer of titanium on the plastic replicas by DC-magnetron sputtering, and the surface characteristics of the experimental implants were evaluated. The experimental implants were placed in the tibias of eight-week-old male SD rats. The rats were sacrificed and the implants harvested at 3, 5, 10, 14, 21 and 28 days after implant placement. The samples were examined by optical microscopy and micro-CT to confirm peri-implant new bone growth. Examination of the experimental implants by SEM imaging showed that the different surface conditions (SA and AE) had been faithfully recreated. TEM observation and XPS analysis confirmed that the coating was titanium. The surface roughness of SA and AE was 2.68±0.536 μm and 0.47±0.069 μm, respectively. With AE, the BMD of peri-implant trabecular bone showed that bone mineralization progressed not on the surface of the implant but at sites a small distance away. At day 28 after placement of the implant, when osseointegration was complete, the BMD value in the region near the implant surface was higher in SA than in AE. Furthermore, the BV/TV value was high at an earlier stage in SA than AE. The results showed that the SA surface was better than the AE surface for achieving osseointegration.福岡歯科大学2013年

Zirconia Implants with Laser Surface Treatment: Peri-Implant Bone Response and Enhancement of Osseointegration

The aim of this study was to prepare zirconia implants with laser-modified surfaces and to evaluate peri-implant tissue response and osseointegration in an animal study. The experimental zirconia implants received one of the following surface treatments and were placed in the tibiae of SD rats: vertical irradiation with a fiber laser (vertical fiber laser), horizontal irradiation with a fiber laser (horizontal fiber laser), vertical irradiation with a Neodymium-doped yttrium orthovanadate (YVO4) laser (vertical YVO4 laser), and horizontal irradiation with a YVO4 laser (horizontal YVO4 laser). The control implants were smooth surfaced. Tibiae with implant bodies were collected 28 days after implant placement, and removal torque values were measured. Tissue sections were prepared for light microscopy, and the bone-implant contact (BIC) ratio and the peri-implant bone area (BA) were measured. The vertical fiber-laser implants had a mean BIC that was significantly higher than other implants. The mean BIC of the vertical fiber-laser implants was approximately 4.2 folds of the value of the control implants on the cortical bone side and approximately 2.7 folds of the value of the control implants on the bone marrow side. The mean BA was significantly higher in the vertical YVO4-laser implants. The vertical fiber-laser implants had a mean torque removal value that was approximately 2.4 folds of the value of the control implants and approximately double of the value of the vertical or horizontal YVO4-laser implants. The horizontal fiber-laser implants had a mean removal torque value that was approximately double of the value of the control implants and approximately 1.7 folds of the value of the vertical or horizontal YVO4-laser implants (p<0.05). Both types of lasers were useful in implant surface treatment to enhance osseointegration of zirconia implants.福岡歯科大学2013年

How to plan and conduct Japanese history lesson aiming to promote historical inquiry: A case of “Sekkanseiji To Insei”

This study proposes the Japanese history lesson plan integrating active historical inquiry by student themselves. Historical inquiry has been regarded as an important strategy to history education fostering democratic citizenship. However, the previous studies in Japan did not seem to clarify the characteristics of historical inquiry and how to apply in the classroom because most of them focused only on the motivation of students. We established the three principles to develop the lesson plan; 1） Procedural concepts are shown to the students explicitly; 2） Various resources is necessary for making diverse historical resources; 3）various activities for promoting active learning by students should be prepared. After conducting the lessons, we found that students actively engaged the class and develop their own historical interpretation. At the end of study, we proposed the future possibilities for bigger reform of history curriculum

Usability of detecting delivery errors during treatment of prostate VMAT with a gantry-mounted transmission detector

Volumetric‐modulated arc therapy (VMAT) requires highly accurate control of multileaf collimator (MLC) movement, rotation speed of linear accelerator gantry, and monitor units during irradiation. Pretreatment validation and monitoring of these factors during irradiation are necessary for appropriate VMAT treatment. Recently, a gantry mounted transmission detector “Delta4 Discover® (D4D)” was developed to detect errors in delivering doses and dose distribution immediately after treatment. In this study, the performance of D4D was evaluated. Simulation plans, in which the MLC position was displaced by 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mm from the clinically used original plans, were created for ten patients who received VMAT treatment for prostate cancer. Dose deviation (DD), distance‐to‐agreement (DTA), and gamma index analysis (GA) for each plan were evaluated by D4D. These results were compared to the results (DD, DTA and GA) measured by Delta4 Phantom + (D4P). We compared the deviations between the planned and measured values of the MLC stop positions A‐side and B‐side in five clinical cases of prostate VMAT during treatment and measured the GA values. For D4D, when the acceptable errors for DD, DTA, and GA were determined to be ≤3%, ≤2 mm, and ≤3%/2 mm, respectively, the minimum detectable errors in the MLC position were 2.0, 1.5, and 1.5 mm based on DD, DTA, and GA respectively. The corresponding minimum detectable MLC position errors were 2.0, 1.0, and 1.5 mm, respectively, for D4P. The deviation between the planned and measured position of MLC stopping point of prostate VMAT during treatment was stable at an average of −0.09 ± 0.05 mm, and all GA values were above 99.86%. In terms of delivering doses and dose distribution of VMAT, error detectability of D4D was comparable to that of D4P. The transmission‐type detector “D4D” is thus suitable for detecting delivery errors during irradiation

Potential role of vacuolar H+–adenosine triphosphatase in neointimal formation in cultured human saphenous vein

AbstractObjective: Vacuolar H+–adenosine triphosphatase plays a pivotal role in pH regulation and molecular transport across the vacuolar membranes and is involved in cell proliferation and transformation. In the present study, possible involvement of vacuolar H+–adenosine triphosphatase in neointimal formation was investigated in an organ culture model of human saphenous vein. Methods and results: Cultured saphenous vein segments developed neointimal formation and marked thickening of the media within 14 days. Neointimal formation and medial thickening were completely inhibited by 10 nmol/L bafilomycin A1, a selective inhibitor of vacuolar H+-adenosine triphosphatase, although structurally related macrolide antibiotics FK-506 and erythromycin were without an effect. The neointimal cells were positive for α-smooth muscle actin and vimentin but negative for desmin, indicative of myofibroblasts. The emergence of myofibroblasts was inhibited, and endothelial cells were preserved in the saphenous vein segments treated with bafilomycin A1. Uptake of bromodeoxyuridine, a proliferation marker, by myofibroblasts was abrogated in the saphenous vein segments treated with 10 nmol/L bafilomycin A1. Detection of apoptotic cells by terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling concomitant with identification of desmin-expressing smooth muscle cells demonstrated that neointimal myofibroblasts, but not medial smooth muscle cells, that expressed desmin underwent apoptosis by treatment with bafilomycin A1. Conclusions: These results suggest that vacuolar H+–adenosine triphosphatase may be involved in myofibroblast growth that contributes to neointimal formation and medial thickening in cultured human saphenous vein. Increased sensitivity of myofibroblasts, but not endothelial cells, and differentiated smooth muscle cells to bafilomycin A1 may have potential therapeutic implications in the treatment for vein graft disease. (J Thorac Cardiovasc Surg 2000;119:998-1007

The effect of AMP kinase activation on differentiation and maturation of osteoblast cultured on titanium plate.

福岡歯科大学2021年

Salmon DNA Accelerates Bone Regeneration by Inducing Osteoblast Migration.

The initial step of bone regeneration requires the migration of osteogenic cells to defective sites. Our previous studies suggest that a salmon DNA-based scaffold can promote the bone regeneration of calvarial defects in rats. We speculate that the salmon DNA may possess osteoinductive properties, including the homing of migrating osteogenic cells. In the present study, we investigated the influence of the salmon DNA on osteoblastic differentiation and induction of osteoblast migration using MG63 cells (human preosteoblasts) in vitro. Moreover, we analyzed the bone regeneration of a critical-sized in vivo calvarial bone defect (CSD) model in rats. The salmon DNA enhanced both mRNA and protein expression of the osteogenesis-related factors, runt-related transcription factor 2 (Runx2), alkaline phosphatase, and osterix (OSX) in the MG63 cells, compared with the cultivation using osteogenic induction medium alone. From the histochemical and immunohistochemical assays using frozen sections of the bone defects from animals that were implanted with DNA disks, many cells were found to express aldehyde dehydrogenase 1, one of the markers for mesenchymal stem cells. In addition, OSX was observed in the replaced connective tissue of the bone defects. These findings indicate that the DNA induced the migration and accumulation of osteogenic cells to the regenerative tissue. Furthermore, an in vitro transwell migration assay showed that the addition of DNA enhanced an induction of osteoblast migration, compared with the medium alone. The implantation of the DNA disks promoted bone regeneration in the CSD of rats, compared with that of collagen disks. These results indicate that the salmon DNA enhanced osteoblastic differentiation and induction of migration, resulting in the facilitation of bone regeneration.福岡歯科大学2016年