Green tea has been reported to have various biological effects, such as inhibition of tumor invasion, inhibition of cell proliferation, apoptosis. Although epigallocatechin-3-gallate (EGCG) and epicatechin (EC) are major components of green tea flavanol, their effect on intra-cellular signal transduction is unknown, Interleukin-6 (IL-6) is a cytokine that influences cellular activation. To determine the influence of IL-6 and EGCG/EC on cellular signal transduction, we investigated tyrosin phosphorylation of Jun-N-terminal kinase (JNK) and Focal adhesion kinase (Fak) on HSC 4 cells treated with IL-6/sIL-6 R and/or EGCG/EC. We found that EGCG./EC induced upregulation of JNK phosphorylation and inhibited Fak tyrosine phosphorylation. It also inhibited matrixmetalloproteteinease activity of HSC 4 cells. These results suggest that EGCG may be useful as an antitumor agent.

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We conducted research as part of a series of studies on the influence on various oral tissues of the offspring of mothers that were given methamphetamine (MA) during pregnancy. The mandibular strength during the growth process of newborn rats from mothers that had received MA were compared with normal newbornes. Methamphetamine hydrochloride was continually administered to mother rats (MA group) every day from conception to the day before delivery. Observations of the newborn were made at birth, 2, 3, 4, and 5 weeks. Newborn rats from mothers who had been administered the same amount of physiological saline solution were used as controls. Peripheral quantitative computed tomography (pQCT) was used to measure bone strength to determine bone mineral density and bone structures. A complete determination was made after soft X-ray photography of the mandible. No significant difference was observed in mandiblar growth from the menton to the gonion between the MA and the control groups throughout the experimental period. Although no difference was noted in trabeculer bone, a significant difference was seen in cortical bone, which tended to become thinner in the MA group. In addition, the cortical bones in the MA group showed lower values for bone mineral density and bone mineral content compared with those in the control group. We concluded that the mandibular strength of neonatal rats of mothers that had received MA was weak, and could break easily compared with normal infants. These results indicate that the problems of female methamphetamine drug users extend to influence on the oral hard tissue formations of their offspring.

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We developed a new three-dimensional system for simulating the outcome of jaw deformity operations using a three-dimensional computed tomography (3D-CT) model of the maxilla and a plaster model of the mandibular dentition. With this system, we were able to estimate the post-operative shape of the face. The model of the mandibular dentition was scanned using a Surflacer (UNSN, Tokyo, Japan). The three- dimensional model of the maxilla that was reconstructed from the Helical CT data was combined with a scan of the dental model to create a 3 D-CT image of the skull. We were able to obtain a precise three-dimensional model of the skull for use in the surgical simulation that was not influenced by metal artifacts. Three points on the occlusal plane were used as base points in the reconstruction. The difference between the pre-operative model and predicted results represents the distance of movement in the operation. By substituting the distance of movement and angle of rotation data and performing a computer Simulation of the sagittal splitting ramus osteotomy, we could predict the post-operative bone structure of the jaw deformity patients before the operation.

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We investigated the relationship between dental treatment stress and function of the autonomic nervous system during dental anesthesia and impression taking. The procedures were administered to five healthy volunteers, once each week for a total of three times. We analyzed the frequency of the R-R interval of the electrocardiogram, and calculated the integrated power values based on the obtained power spectrum for the respective components in the low frequency band (LF : 0.04-0.15Hz) and high frequency band (HF : 0.15-0.40Hz). The ratio of LF to HF was used as an index of sympathetic nervous system function. This ratio decreased with repeated impression taking, but not with repetition of dental anesthesia. We found that different procedures produced different stresses.

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We did on electrophysiological study to examine supraacute changes in the somatosensory evoked potential (SEP) of gerbils following transient forebrain ischemia and reperfusion. The bilateral carotid arteries were ligated for 12. Fig. 1 shows six gerbils classified as the ischemia group. The control groups recieved a sham operation. The regional cortical cerebral blood flow (r-CBF) and brain temperature were monitored for both groups. SEP devices were attached to the animals and baseline measurements were obtained. Transient forebrain ischemia was achieved in the ischemia group by ligation of the carotid arteries for 5 minutes. R-CBF and SEP were measured in both groups for 30 minutes after either reperfusion or the sham operation. R-CBF decreased 30minutes after the sham operation in the controls. In the ischemia group, r-CBF increased after reperfusion for hyperemia. While SEP latency was stable in the controls during the measurements, it disappeared after reperfusion in the ischemia group. We concluded that it is difficult to evaluate neurological dysfunction in gerbils following transient forebrain ischemia and reperfusion using SEP. A total examination may be needed that includes other neurological factors, such as glutamate, and other hemological factors.

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The high-pull headgear appliance is used to control the vertical anchorage of maxillary molars in the orthodontic treatment of maxillary protrusion, preventing over growth of the maxilla, and mandibular clockwise rotation. We studied changes in cephalogram indexes of 32 female maxillary protrusion patients between 13 and 15 years of age who were treated with and without the high-pull headgear. Sixteen of them used the headgear, and another 16 did not. The cephalograms of the subjects were recorded and the indexes were measured. The Student's t-test showed a significant difference in FMA at the 1% level between the two groups. Although FMA decreased in the group treated with the high-pull headgear, it increased in the group without the headgear. The difference between the two groups was about 3.1 degrees. There was a significant difference at the 5% level in changes of ANB. The group treated with the headgear showed a greater decrease in ANB than did the controls. The average difference was about 1.3 degrees. There were no significant differences in changes of other indexes, such as SNA. We concluded that the high-pull headgear prevents mandibular clockwise rotation and improves ANB by controlling vertical elements.

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We developed a new simulation method for predicting patients' post treatment cephalometric data from their pre-treatment cephalometric measurements. We measured the cephalograms before and after treatment of ten female orthodontic patients between 18 and 24 years of age. We calculated the simulated post treatment cephalometric measurements with the newly developed method and compared the simulated data with the actual post treatment measurements. We constructed the bit map model of the teeth and alveolar bone from the patient's cephalograms and calculated the amount of bone reconstruction on the bit map model using a personal computer. Tooth movement was simulated based on the least bone reconstruction. There were significant differences at the 5% level in the inclination of the maxillary and mandibular canines. There was no significant difference in any other index. We concluded that the new method is useful for accurately estimating tooth movement after treatment.

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