This study was designed to radiographically evaluate the effect of surface macro-and microstructures within the coronal portion of the external hex implant at the marginal bone change after loading. The fifty-four patients included in the study were randomly assigned to treatment groups with rough-surface implants (TiUnite, n = 45), a hybrid of smooth and rough surface implants (Restore, n = 45) or rough-surface with microthreads implants (Hexplant, n = 45). Clinical and radiographic examinations were conducted at the time of implant loading (baseline) and at 1-year post-loading. A three-level mixed-effect ancova was used to test the significance of the mean marginal bone change of the three implant groups from baseline to 1-year follow-up. At 1-year, significant differences were noted in marginal bone loss recorded for the three groups (P < 0.0001). The rough surface with microthread implants had a mean crestal bone loss of 0.42 +/- 0.27 mm; the rough surface implants, 0.81 +/- 0.27 mm; and the hybrid surface implants, 0.89 +/- 0.41 mm. Within the limitations of this study, a rough surface with microthreads at the coronal part of implant maintained the marginal bone level against functional loading better than implants without these two features.

The purpose of this study was to evaluate the geometry and surface characteristics of osseointegration after functional loading by radiographic, periodontal and histomorphometric analyses. We analysed three groups of implants with different geometry and surface characteristics using experimental dogs. The control group received Brånemark implants (group 1). Group 2 and group 3 implants each had a 0.5-mm pitch height but differed in surface characteristics. Group 2 implants were machine surfaced and group 3 implants were thermally oxidized at 800 degrees C for 2 h in a pure oxygen atmosphere. For these experiments, which used a total of four healthy beagle dogs, the implants were randomly installed into the extracted first, second and third premolar positions. The animals received radiographic and clinical periodontal examinations at 6 and 12 months post-loading, and were then killed for histomorphometric analysis. The radiographic analysis showed that mean crestal bone resorption in the control group was greater than that observed in the experimental groups (P < 0.05). The percentage of bone-to-implant contact for group 3 (83.7%) was significantly higher than in groups 1 (74.4%) and 2 (75.0%) (P < 0.05). Overall, implant geometry and surface treatment affected the rate of crestal bone resorption and bone healing surrounding the dental implants.

The rate of increase in the number of aging population in Korea is very rapid among OECD-member countries. And fall accident is one of the most common factors that threaten the health of the elderly. Therefore, it is needed to develop a fall detection system for the elderly. Most fall detection systems use accelerometers attached on the torso. And in various studies, it was verified that these systems have high sensitivity and high specificity. However, the elderly would feel uncomfortable when banding a sensor on the chest every day. Therefore, in this study, we attached an accelerometer on the shoes to detect fall in the elderly. This prototype system would be improved as a smaller, low-power system in the next study. Also, applying energy harvesting device to this shoe system is being developed to reduce the weight of battery.

Silymarin has been shown to exhibit hepatoprotective effects against chemical‐induced liver injury, but the underlying mechanism of its beneficial action remains unclear. In this study we examined the changes in hepatic metabolism of sulfur‐amino acids induced by silymarin. Male mice were treated with silymarin (100 or 200 mg/kg, po) every 12 hr for a total of 3 doses. Methionine level was increased, but methionine adenosyltransferase (MAT) activity was decreased by silymarin in a dose‐dependent manner. S‐Adenosylmethione or homocysteine was not altered whereas cystathionine, cysteine and glutathione levels were increased significantly by silymarin treatment. Western blotting analysis revealed that silymarin treatment decreased protein expression of betaine‐homocysteine methyl transferase, MATI/III and cysteine dioxygenase, but increased cystathione β‐synthase expression in liver. Expression of γ‐glutamylcysteine synthetase, the rate‐limiting enzyme of glutathione synthesis, was not influenced. The present results show that silymarin induces significant changes in the metabolomics of sulfur‐containing substances in liver, which appears to be associated with the hepatoprotective effects of this substance. Further studies to identify its significance in chemical‐induced liver injury are currently being conducted in this laboratory. Grant Funding Source: KOSEF

The effect of a single administration of aromatic hydrocarbons (AHCs) on the metabolic activity responsible for the biotransformation of dichloromethane (DCM) to carbon monoxide (CO) was investigated using adult female rats. In rats treated orally with benzene (1.5 ml kg−1), toluene (2.0 ml kg−1) or m‐xylene (2.0 ml kg−1) 16–24 h prior to DCM (3 mmol kg−1, i.p.), the carboxyhaemoglobin (COHb) level was elevated, reaching peaks in blood at 21%, 16% and 23%, respectively, compared to the peak of ca. 10% in rats treated with DCM only. Their effects on COHb generation were highly dependent on the time interval between each AHC and DCM treatment, since an early administration of m‐xylene or toluene decreased the COHb elevation. The half‐life of DCM in blood was shortened significantly, indicating that the metabolic degradation of DCM was enhanced by the AHCs. Disulfiram (3.4 mmol kg−1, p.o.) blocked COHb elevation completely, suggesting that the metabolic conversion of DCM to CO is mediated by cytochrome P‐450 2E1 (P4502E1). Corresponding increases in the concentration and half‐life of DCM in blood were also observed. A single administration of the AHCs did not alter the hepatic glutathione level, suggesting that the increase in DCM‐induced COHb elevation was not due to hepatic glutathione depletion. In vitro studies showed that the hepatic microsomal metabolism of nitrosodimethylamine and p‐nitrophenol was significantly increased by a single dose of each AHC. Total cytochrome P‐450 content and p‐nitroanisole demethylase activity were also increased; however, only toluene and m‐xylene were effective inducers for aminopyrine N‐demethylase. Therefore, benzene appears to be a selective inducer for P4502E1 compared to other alkylbenzenes. The results indicate that even a single dose of benzene, toluene or m‐xylene may induce the activity of P4502E1 significantly, which is responsible for the increased generation of COHb from DCM, as demonstrated in the present study.