We investigated the influence of administering tandospirone citrate for improving the anxiety level of patients with painful temporomandibular disorders. The participants were recruited from the patients who visited the 1st Department of Oral Surgery in Tokyo Medical and Dental University or the Department of Dentistry in Jikei University School of Medicine from May 1 to December 31, 1999. The tandospirone citrate (30 or 60 mg/day) was administered to the participants for eight weeks. No other therapy was given to the participants except for giving a general instruction to rest the masticatory system. Signs, symptoms and psychological ratings for anxiety, depression and personality traits were recorded at four and eight weeks after the start. The state of anxiety was evaluated by using the Hospital Anxiety and Depression Scale (HADS) . Of the total of 58 participants, 37 cases were eligible for analyses. Anxiety score decreased in eight cases although it increased or was unchanged in 29 cases. In comparison between the improved and non-improved group, anxiety (p=0.001), depression (p=0.008) and neuroticism (p=0.007) scores at the baseline in the improved group were significantly higher than in the non-improved group. while visual analogue scales for pain (p=0.012) and mouth opening difficulty (p=0.004) at eight weeks in the improved group were significantly lower than in the non-improved group. These results suggested that the improvement of state of anxiety would effectively improve the objective ratings for symptoms.

View full abstract

Platelet-rich plasma (PRP), which is obtained by centrifuging autologous blood, contains a large number of platelets. When platelets are activated using substances such as thrombin, α granules release platelet released growth factor (PRGF) such as platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) . Since these growth factors promote proliferation and differentiation of cells that are required for tissue regeneration, PRP has been used for bone and periodontal tissue regeneration in clinical dentistry. In the present study, we investigated the changes in PDGF-AB levels before and after platelet activation using ELISA. In addition, cellular proliferation was investigated by adding platelet released supernatant (PRS) produced by activating platelets of PRP to mesenchymal stem cell (MSC) culture media using MTS assay.
The results showed that the level of PDGF-AB in PRS was 5.31 times higher than that before platelet activation. Furthermore, adding PRP or PRS significantly promoted MSC proliferation compared to the control, and adding PRS enhanced cellular proliferation in a dose-dependent manner from days 1 to 4 of culture. This study suggested that activation of platelets in PRP releases and concentrates PRGF, and that adding PRS to MSC promotes early cellular proliferation of MSC.

View full abstract

There is growing evidence that osteopontin (OPN) plays an important role in cell migration, which is one of the key events in the immune response, and tumor metastasis and invasion. Although OPN is recognized generally as a secreted protein, we have shown the presence of an intracellular form of OPN (iOPN) in migrating fibroblasts, activated macrophages, motile osteoclasts and metastatic cells, which indicates the importance of iOPN in cell migration. In this study, we examined the effects of exogenous OPN on the impaired cell spreading and migration observed in OPN-null osteoclasts, to determine whether iOPN has functional significance in osteoclast motility. The results show that 1) in osteoclasts, generated from OPN-null bone marrow cells in the presence of M-CSF and RANKL, cell spreading and protrusion of pseudopodia were reduced and cell fusion was impaired, which resulted in smaller osteoclasts with fewer nuclei, 2) osteoclast migration towards M-CSF was significantly compromised in OPN-null mice, and 3) exogenous OPN, which was pre-coated onto the Transwell^TM membrane, failed to restore the impaired osteoclast spreading and migration observed in the OPN-null mice. These findings have identified an intracellular form of OPN that appears to function in the migration and fusion of osteoclasts.

View full abstract

In the 1960s, Seeman et al, reported the effects of local anesthetics on the cell membrane, stating that low concentrations of local anesthetics strengthen the erythrocyte membrane and exert an antihemolytic effect as a result, but high concentrations of them cause hemolysis. There have been other reports concerning the interaction between anesthetic potency and hemolysis. In this study, we determined the antihemolytic effect of local anesthetics in human erythrocyte membrane and their correlation to anesthetic potency. Each local anesthetic was added at various concentrations (0-10mM) to isotonic TRIS. LA isotonic TRIS was added to 75μL of erythrocyte solution. Subsequently, hypotonic TRIS which had the same concentration of local anesthetic as the LA isotonic TRIS, was added. The resultant solution was centrifuged at 12, 000g for 5 min. The absorbance of the supernatant to a wavelength of 540nm was measured using a spectrophotometer. The antihemolytic effect of the local anesthetic at each concentration was obtained by the following formula: (Absorbance of local anesthetic at concentration of 0 mM absorbance of local anesthetic at each concentration [0.1-10mM] ) / (absorbance of a local anesthetic at concentration of 0 mM) .
Procaine did not show at express antihemolysis effect. Lrdocaine indicated an antihemolysis ef-fect of 0.4mM and between 0.8 and 10mM between the control (p<0.05) . Prilocaine indicated an antihemolysis effect of 2 to 10mM between the control (p<0.05) . Mepivacaine indicated antihe-molysis effect of 2 to 4 mM between control (p<0.05) . Articaine indicated an antihemolysis effect of 0.6mM to 10mM between the control (p<0.05) . Based on these results, if an anesthetic has a direct action on nerve fiber, anesthetic potency is in the following order: lidocaine≥articaine>mepivacaine=Prilocaine.

View full abstract

Clarithromycin (CAM) concentrations in human serum, gingiva, mandibular bone, and dental follicle following a single oral administration of CAM (200 mg) were studied. The mean concentrations in serum, gingiva, mandibular bone, and dental follicle peaked at identical times, 2.5 h after administration, and were 1.46 μg/mL, 2.04, 1.35, and 1.94 μg/g, respectively. The mean concentration ratios of gingiva/serum, mandibular bone/serum, and dental follicle/serum at the peak time were 1.61, 1.02, and 1.67, respectively. Most of the CAM concentrations in gingiva, mandibular bone, and dental follicle exceeded the MIC for 80% of clinically isolated strains of oral streptococci. Thus, CAM may be a valuable antimicrobial agent for oral surgery.

View full abstract