<ORIGINAL ARTICLE>Tartrate-resistant acid phosphatase activity induced by pre-incubation with tartrate in mouse embryonic mandibles

The present study used mouse embryonic mandibles to examine the characteristics of tartrate in tartrate-resistant acid phosphatase (TR-ACPase) histochemistry. Short-term incubation (30 min) in substrate-containing reaction medium showed intense and specific activity of TR-ACPase only in a small number of mononuclear cells, presumably pre-osteoclasts, present around a population of differentiating osteoblasts. Pre-incubation with tartrate and subsequent incubation of reaction medium resulted in slightly increased intensity in the preosteoclasts and also weak enzyme activity in other cells such as oral and dental epithelia, osteoblasts, and chondrocytes of Meckel\u27s cartilage. Pre-incubation with tartrate and subsequent incubation with reaction medium may result in overestimation of the histochemical products. Therefore short-term incubation is important to estimate the enzyme activity exactly in TR-ACPase histochemistry. especially in osteoblasts

<ORIGINAL>Appearance and distribution of osteoclast precursors and the morphological change during mouse mandibular osteogenesis

The appearance and distribution of osteoclast precursors and the morphological change of the precursors were examined during mouse mandibular osteogenesis, using enzyme histochemistry of tartrate-resistant acid phosphatase (TRAPase). Osteogenic tissue was not observed in the prospective region of the mandibles at embryonic day 12 (E12), but TRAPase-positive cells often existed in the region. Immature osteoblasts were seen as a population in E13 mandibles, and a thin layer of bone matrix had been formed at the central part of the osteogenic region in E14 mandibles. A number of TRAPase-positive osteoclast precursors were tandemly localized along the region. At these stages, the TRAPase-positive cells were oval and round in the vicinity of blood vessels, but at an earlier stage of the osteogenesis, the positive cells extended long processes towards the interspace between the osteoblasts. The present results demonstrated the morphology characteristic of the TRAPase-positive osteoclast precursors during osteoclast differentiation, suggesting the possibility that there is a cell-cell interaction between the osteoclast precursors and the osteoblasts in vivo

<ORIGINAL ARTICLE>Localization of anti-monocyte/macrophage antibody-positive cells in periodontal tissue of rat maxillary molars after orthodontic tooth movement

To examine the localization of monoclonal anti-monocyte/macrophage (ED1) and macrophage (ED2) antibody-positive cells in periodontium, rat maxillary molar teeth were moved by insertion of band materials. The orthodontic tooth movement was elicited for 5 days, and paraffin-embedded maxillary teeth were stained by fluorescent immunocytochemistry and observed using a confocal laser scanning microscope. The localization of ED1-positive mononuclear cells in the experimental teeth was little different from that in the controls. While ED2-positive mononuclear cells were located throughout the periodontium on the distalside of controls, the number of positive cells decreased on the pressure side of the treated teeth. The present study suggested that most of the immunoreactive mononuclear cells on the distal side of controls are macrophages, while the positive cells on the pressure side of the experimental teeth are osteoclast precursors and a small number of macrophages

Standalone Percutaneous Vertebroplasty for Hyperextension Injuries of the Ankylosed Thoracolumbar Spinal Kyphosis

Hyperextension injuries of the ankylosed thoracolumbar spine, particularly those with preexisting kyphotic deformity, present significant therapeutic challenges. The authors viewed that such injuries without displacement or fractures of the posterior elements are reasonable candidates for standalone percutaneous vertebroplasty (PVP). In such cases, the posterior tension band is spared; thus, fractures are unstable not in the lateral direction, which would lead to the translation of the fracture, but in the vertical direction. Such vertical instability of the fracture can be stabilized if the open mouth-type vertebral cleft is adequately filled with a sufficiently large amount of polymethylmethacrylate (PMMA) cement. Our three patients receiving standalone PVP received injections of 12 mL, 16.5 mL, and 18 mL of PMMA cement. This minimally invasive surgical procedure achieved both short-term (immediate pain relief and mobilization) and long-term (fracture healing) goals

<ORIGINAL ARTICLE>Histologic investigation of tissue surrounding bone in a HA-coated implant supported super structure with and without stress-absorbing elements

The effectiveness of the implant-supported overdentures has been attracted attention for edentulous patients, and a number of studies have been reported. Implant-supported overdentures refer to implant-retained tissue-borne overdentures and it is different from the implant-supported fixed partial dentures recommended by Branemark. In implant-supported overdentures, the functional load may concentrate on implant where there is rigid connection. Loaded implants may cause a resorption of surrounding bone, leading to malfunction, loosing, and the ultimate failure of the implant. The present study reports a stress-absorbing element using a resilient compound designed as the super structure of a two-piece titanium core with hydroxyapatite coated cylinder implants, to avoid stress concentrations, and a histological comparison of the surrounding bone tissue with rigid elements. No notable histological differences were observed in the trabecular patterns by contact microradiography and light microscopy

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Predictive factors for understanding in fundamental radiology study were statistically evaluated on dental education. The investigation was made with 86 students in the fourth grade dental school in the 1999 school year. The average points in the test of fundamental radiology were compared for each group divided by predictive factors. The relationship between the total points scored and the predictive factors were analyzed by multivariate analysis. The statistical results showed that learning physics in high school made a significant contribution to understanding fundamental radiology. Teaching physics in the university was found to be very important for understanding in fundamental radiology study

Novel, Objective, Multivariate Biomarkers Composed of Plasma Amino Acid Profiles for the Diagnosis and Assessment of Inflammatory Bowel Disease

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic intestinal disorder that is associated with a limited number of clinical biomarkers. In order to facilitate the diagnosis of IBD and assess its disease activity, we investigated the potential of novel multivariate indexes using statistical modeling of plasma amino acid concentrations (aminogram). METHODOLOGY AND PRINCIPAL FINDINGS: We measured fasting plasma aminograms in 387 IBD patients (Crohn's disease (CD), n = 165; ulcerative colitis (UC), n = 222) and 210 healthy controls. Based on Fisher linear classifiers, multivariate indexes were developed from the aminogram in discovery samples (CD, n = 102; UC, n = 102; age and sex-matched healthy controls, n = 102) and internally validated. The indexes were used to discriminate between CD or UC patients and healthy controls, as well as between patients with active disease and those in remission. We assessed index performances using the area under the curve of the receiver operating characteristic (ROC AUC). We observed significant alterations to the plasma aminogram, including histidine and tryptophan. The multivariate indexes established from plasma aminograms were able to distinguish CD or UC patients from healthy controls with ROC AUCs of 0.940 (95% confidence interval (CI): 0.898-0.983) and 0.894 (95%CI: 0.853-0.935), respectively in validation samples (CD, n = 63; UC, n = 120; healthy controls, n = 108). In addition, other indexes appeared to be a measure of disease activity. These indexes distinguished active CD or UC patients from each remission patients with ROC AUCs of 0.894 (95%CI: 0.853-0.935) and 0.849 (95%CI: 0.770-0.928), and correlated with clinical disease activity indexes for CD (r(s) = 0.592, 95%CI: 0.385-0.742, p<0.001) or UC (r(s) = 0.598, 95%CI: 0.452-0.713, p<0.001), respectively. CONCLUSIONS AND SIGNIFICANCE: In this study, we demonstrated that established multivariate indexes composed of plasma amino acid profiles can serve as novel, non-invasive, objective biomarkers for the diagnosis and monitoring of IBD, providing us with new insights into the pathophysiology of the disease

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Two radiopaque lines demonstrated in the mandibular molar regions have customarily been termed to be "external oblique line" and "internal oblique line". But, even in the textbooks for dental radiology, some defferences are seen in the explanation of them. Therefore, the textbooks for oral anatomy, dental radiology, complete prodentics and dental anesthesia in which the terms "external oblique line" and "internal oblique line" were reviewed. The results show that the "external oblique line" and "internal oblique line" are homonymic words derived by the difference of the purpose to use. If one uses such names properly in education, students must learn the different meanings doubly or threefold, and it might obstruct the commonness between these subjects