Decision tree analysis for factors associated with dental caries in school-aged children in Japan.

OBJECTIVE: Our study aimed to elucidate the interactive relationship between factors associated with dental caries in school children using decision tree analysis. RESEARCH DESIGN: Cross-sectional study Methods: Participants were recruited from public primary schools (9-12 years, 4th to 6th grade) and junior high schools (12-13 years, 1st grade) in Japan. A total of 1775 students (928 boys and 847 girls) were analyzed. Questionnaire survey, oral examination, and saliva test were performed. Multiple logistic regression and decision tree analysis were performed. RESULTS: Multiple logistic regression showed an association between dental caries and toothpaste use, dental attendance and the presence of Streptococcus mutans. Decision tree analysis showed that students with non-regular dental attendance were at a significantly higher risk of dental caries at the late stage of primary school. At the early stage of primary school, high levels of Streptococcus mutans and male sex were factors associated with dental caries. In students with low levels of Streptococcus mutans, using toothpaste occasionally was associated with a high risk of dental caries. CONCLUSIONS: In early primary school years, S. mutans may be a useful screening and diagnostic tool for dental caries. In students with high levels of S. mutans, sex may be associated with dental caries. Furthermore, in students with low levels of S. mutans, regular use of toothpaste should be encouraged, and in late primary school years, regular dental attendance should be encouraged to prevent dental caries.

Conventional and surgical endodontic retreatment of a maxillary lateral incisor with unusual anatomy.

AIM: To describe conventional and surgical endodontic treatment of a maxillary right lateral incisor with an unusual root dilaceration and to discuss the treatment outcome. SUMMARY: Root dilacerations refer to severe curvature or angulations that may occur anywhere along the length of a root. This anatomical deviation may present an unfavourable outcome if clinicians fail to recognize the difficulties. The following case report describes conventional and surgical endodontic treatment of a maxillary right lateral incisor with an unusual root dilaceration. *Root morphology may present a challenge for clinicians during root canal treatment. *Clinicians should be aware of the importance of surgical endodontics and be familiar with microsurgery principals and techniques.

[Successful treatment for descending necrotizing mediastinitis; report of a case].

A case of a 55-year-old man with descending necrotizing mediastinitis (DNM) after a tooth removal was reported. Chest computed tomography (CT) showed a fluid collection in the right thorax, in the cervical region and in the mediastinum. The patient underwent cervical drainage and thoracoscopic pleural dissective drainage. The cervical and right anterior thoracic drain was removed on the 6th day and posterior drain was removed on the 8th day after the operation. The patient was discharged on the postoperative day 13, and showed no recurrence.

Changes in membrane surface properties of hepatic peroxisomes of rats under several conditions as determined by partition in aqueous polymer two-phase systems.

Changes in membrane surface properties of hepatic peroxisomes of rats under several conditions were observed by aqueous polymer two-phase systems, which contained 6% (w/w) dextran T 500, 6% (w/w) polyethyleneglycol 4000, 250 mmol sucrose/kg and various concentrations of sodium phosphate buffer. The partition of peroxisomes into the upper phase depended to a large extent on their membrane surface charge. The cross-points of peroxisomes shifted from 5.55 to 5.25 and 5.2 after the administration of clofibrate and aspirin for 2 weeks, respectively, although that of alloxan-diabetic rat peroxisomes was not altered. The hydrophobic properties of peroxisomes, examined by means of a partition containing polyethyleneglycol monostearate, were altered by diabetes and starvation, but no change occurred in rats treated with clofibrate or aspirin. In the liver of rats fed a high-fat diet, the partition of peroxisomes was the same as that of the control. These findings indicate that hypolipidemic drugs such as clofibrate and aspirin induce the proliferation of peroxisomes and lead to the alteration of the surface charge of peroxisomal membranes. Diabetes or fasting lead to an alteration mainly of the hydrophobic properties. Both changes are probably due to alteration of content and/or composition of the proteins and the phospholipids in peroxisomal membrane under the conditions used.

Hmg-CoA reductase inhibitor modulates monocyte-endothelial cell interaction under physiological flow conditions in vitro: involvement of Rho GTPase-dependent mechanism.

3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, have been reported to exert actions independent of their lipid-lowering effects. To critically assess the effects of statins on monocyte-endothelial cell interactions, we used an in vitro model that mimicked physiological flow conditions. Monocytic U937 cells were incubated in the presence of cerivastatin for 48 hours. Adhesive interactions of statin-treated U937 cells were then analyzed by use of activated (interleukin-1beta 10 U/mL, 4 hours) human umbilical vein endothelial cells in an in vitro flow apparatus. Flow cytometric analysis of adhesion molecules and measurement of F-actin content in U937 cells were performed before and after statin treatment. Preincubation with cerivastatin significantly decreased U937 firm adhesion to activated human umbilical vein endothelial cells, whereas U937 rolling was not decreased. Fluorescence-activated cell sorter analysis revealed downregulation of U937 surface expression of CD11a, CD18, and VLA4 after statin treatment. Cerivastatin significantly reduced F-actin content in U937 cells and inhibited RhoA translocation, whereas preincubation with C3 exoenzyme reduced U937 adhesion under flow. Cerivastatin reduces monocyte adhesion to vascular endothelium under physiological flow conditions via downregulation of integrin adhesion molecules and inhibition of actin polymerization via RhoA inactivation. Our findings have important implications for the lipid-independent effects of statins.

Characterization of soluble thrombomodulin fragments in human urine.

The soluble thrombomodulin (TM) subspecies in human urine detected by polyclonal anti-human TM IgG were isolated and characterized. 105, 85, 80, 56, 33, 31 and 28 kDa subspecies under reducing conditions was comparable to 78, 66, 56, 200, 52, 30 and 25 kDa under non-reducing conditions, respectively, in the two-dimensional electrophoresis. Each subspecies under non-reducing conditions, except the 200 and 52 kDa molecules, was constituted of single subspecies, whereas the 200 and 52 kDa molecules were constituted of the tetramer of the 56 kDa subspecies of reducing conditions and a dimer of the 33 kDa subspecies, respectively. NH2-terminal amino acid sequences of the 105, 85 and 80 kDa subspecies maintained Ala1-Pro2-Ala3- of intact human TM, however, 56, 33, 31 and 28 kDa subspecies started from Glu137-Gln138-, Gln214-Gly215-, Ser228-Val229- and Ala240-Ile241-, respectively. All subspecies obtained under non-reducing conditions exhibited cofactor activity for thrombin-dependent protein C activation ranging from 58 to 162 pmol APC/min/nmol TM at 0.4 mM Ca2+ indicating that all of the subspecies maintained the fourth to sixth repeat of epidermal growth factor-like structure of intact TM. 85, 80, 56, 33, 31 and 28 kDa subspecies were suggested to lack both chondroitin sulfate glycosaminoglycan (CSGAG), transmembrane and cytoplasmic domains of intact TM, while 105 kDa subspecies lack only CSGAG from the results of kinetic properties and the interaction with phospholipid vesicles composed from phosphatidylcholine and phosphatidylethanolamine.

Proton pump inhibitor modifies inflammatory reaction in human gastric mucosa infected by Helicobacter pylori.

AIM: To examine whether proton pump inhibitors modify the production of oxygen-derived free radicals and related cytokines in the human gastric mucosa infected with H. pylori. METHODS: Thirty-four H. pylori-positive peptic ulcer patients (23 gastric ulcer, 11 duodenal ulcer) were enrolled. Biopsy tissue samples were obtained endoscopically from the antrum and corpus. Tissue content of neutrophil myeloperoxidase (myeloperoxidase) and IL-8 was measured by ELISA. Mucosal production of oxygen-derived free radical was measured using luminol-dependent chemiluminescence (ChL). A proton pump inhibitor (either lansoprazole 30 mg, omeprazole 20 mg, or rabeprazole 10 mg) was administered daily by mouth to all patients for 8 weeks. Endoscopic examination was then repeated, and biochemical analysis was performed. RESULTS: Antral myeloperoxidase decreased significantly after proton pump inhibitor treatment (5.23 +/- 7.00-2.76 +/- 5.11 ng/mg, P < 0.02), but corpus myeloperoxidase was unchanged. IL-8 was also modified by proton pump inhibitors and these changes were parallel to those of myeloperoxidase. Corpus ChL was significantly increased from 88.5 +/- 69.8-159 +/- 172 counts/10 s/mg after proton pump inhibitor treatment, whereas antrum ChL was not altered. H. pylori infection rate was decreased in the antrum as well as the corpus. CONCLUSIONS: Proton pump inhibitor treatment stimulated oxygen-derived free radical production in the corpus mucosa.

Effect of Triton WR-1339 on the rates of synthesis and degradation of hepatic catalase of rat.

The effect of Triton WR-1339 on the rates of synthesis and degradation of hepatic catalase was examined. Triton WR-1339 was injected intraperitoneally into rats at a dose of 200 mg per 100 g body weight. Catalase activity decreased to about 35% of that of the control at 42-48 h after the injection and recovered to the normal level at 96 h. Other peroxisomal enzymes, D-amino acid oxidase and urate oxidase, showed similar patterns of the activities to those of catalase. During the first 48 h after the injection of Triton WR-1339, the rate of catalase synthesis (ks) fell to below a detectable value, while that of the degradation (kd) did not show any significant change. On the other hand, during the period 48-96 h after the injection, the rate of the synthesis (ks) returned to the normal level though that of the degradation (kd) decreased to about 50% of the control.

Developmental expression of vascular endothelial growth factor in the masseter muscle of rats.

Developmental changes in vascular endothelial growth factor (VEGF) in rat masseter after birth were investigated. VEGF was extracted efficiently and reproducibly from muscle homogenate with low concentrations of non-ionic detergents, such as Triton X-100, Nonidet P-40, and Tween 20. The amount of VEGF measured by enzyme-linked immunosorbent assay (ELISA) increased markedly by approximately 9-fold, from day 8 to 35 after birth. The increase in VEGF was closely correlated with the development of the capillary network, as shown by the capillary to muscle fibre ratio (C/F ratio). Immunoblotting revealed that the predominant molecular species of VEGF concentrated with heparin-sepharose beads was VEGF(188). These results suggest that VEGF plays an important part in the development and maintenance of the capillary network in the rat masseter.

A mild transient decrease of peripheral red blood cell counts induced by a suprapharmacological dose of pegylated human megakaryocyte growth and development factor in rats.

Previous studies have shown that pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) at suprapharmacological dose induces a mild transient decrease of red blood cell counts according to thrombopoiesis in normal mice. To unravel the mechanism underlying this mild transient decrease of red blood cells, we have studied the effect of PEG-rHuMGDF on the circulating plasma and blood volume, and the serum biochemical parameters of anaemia and splenectomy. Also, we have performed histological studies of the bone marrow and the spleen of PEG-rHuMGDF-treated rats. PEG-rHuMGDF (300 microg kg(-1)]) or vehicle was subcutaneously administered to rats once a day for up to five days. From day 6 after the start of PEG-rHuMGDF administration, the platelet counts and plateletcrit levels were significantly increased, reaching peak values on day 10, and recovering to normal by day 20. The red blood cell counts and the haematocrit levels were significantly decreased on day 6 to 13. The decreases in red blood cell levels and haematocrit produced by PEG-rHuMGDF treatment were mild and had recovered by day 15. The plasma and blood volumes were significantly increased on day 10 in PEG-rHuMGDF-treated rats. No alteration of the serum biochemical parameters for anaemia, iron or total bilirubin, were observed on day 10. The histological examination on day 10 revealed a marked increase in megakaryocytes and a slight decrease in erythropoiesis in the bone marrow of rats that received PEG-rHuMGDF (300 microg kg(-1)). There was also a slight increase in splenic megakaryocytes and erythropoiesis. The decrease of red blood cells by PEG-rHuMGDF was not affected by splenectomy. These results suggest that the mild transient decrease of red blood cells induced by PEG-rHuMGDF treatment for up to five days is based mainly on the increases in the plasma and blood volume. These events are secondary changes due to the regulation of the excess production of megakaryocytes in the marrow and the peripheral platelets.

Preoperative application of limited cone beam computerized tomography as an assessment tool before minor oral surgery.

We describe the preoperative application of limited cone beam computerized tomography (CT) using a Dental three-dimensional (3D)-CT as an assessment tool before minor oral surgery. The Dental 3D-CT provided 42.7 mm-high and 30 mm-wide rectangular solid images. This size covered the height of the mandible with standing teeth. Dental 3D-CT clearly demonstrated lesions in the maxillary and mandibular bone. Resorption of the bone due to disease expansion was depicted more clearly on the Dental 3D-CT than on conventional radiographs. Information about lesion location and the relationship between the lesions and their adjacent anatomical structures, such as the mandibular canal and maxillary antrum, was useful for minor oral surgery. Due to its high resolution and low radiation dose, Dental 3D-CT was useful for preoperative examination prior to minor oral surgery.

Partial inferior turbinectomy during secondary alveolar bone grafting.

This study examined the characteristics and outcome of patients undergoing partial inferior turbinectomy during secondary alveolar bone grafting. Thirty-three of 55 patients with cleft lip and palate or cleft lip and alveolus who underwent secondary alveolar bone grafting concurrently received partial inferior turbinectomy to ensure that the height of the nasal floor was similar on the cleft side and non-affected side. At the time of surgery, patients who underwent turbinectomy were significantly older than those who did not undergo the procedure. The proportion of patients who underwent turbinectomy was significantly higher among patients with cleft lip and palate than among those with cleft lip and alveolus. These differences apparently reflected the developmental stage of the inferior turbinate and the relative severity of alveolar and palatal defects. In most patients who underwent partial inferior turbinectomy, postoperative X-ray films revealed excellent bone formation at the graft site. Our findings suggest that partial inferior turbinectomy during secondary alveolar bone grafting is a very useful procedure that facilitates dissection to the height of the nasal floor, reconstruction of the mucosal nasal floor, and formation of a sufficient bone bridge. It also promotes alveolar cleft closure, especially in patients with wide bone defects.

A repeated-dose dermal toxicity study of hydrophobically modified hydroxypropyl methylcellulose in rats.

A six-month repeated-dose dermal toxicity study followed by a 30-day recovery test of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC), a new cellulose derivative used as a thickener for topical pharmaceuticals, was conducted using rats. Aqueous paste of HM-HPMC was applied to the skin of rats once daily at dose levels up to 60 mg/kg/day, which was the highest dose that could be administered. Items checked included general signs, urinalysis, hematology, ophthalmology, and histopathology. One rat died during the administration period owing to a malignant tumor in the hemopoietic system, which was not attributed to the test substance. Statistically significant differences were found in some test results, but those were not dose-dependent and were considered to be incidental or spontaneous. It was concluded that the test substance was not toxic upon chronic dermal administration at dose levels up to 60 mg/kg/day.

Assessment of the development of hand and mouth coordination when taking food into the oral cavity.

The purpose of this study was to establish an assessment method for evaluation of hand and mouth coordination during self-feeding. The subjects were four normally developed infants. Their feeding behavior was videotaped at two or four week intervals (from age eight months to thirty-six months). The items analyzed were nine viewpoints for finger feeding and eight viewpoints for spoon-feeding. The results obtained included: finger feeding--development of cylinder and pinch grasp, two patterns of hand in relation to neck and trunk, placement of food into the mouth, developmental aspects of neck rotation when taking food with the lips; spoon feeding--holding technique, flexion of elbow and shoulder, taking food from the spoon bowl by the lips, patterns of neck rotation. From the results of these observations, we conclude that the items analyzed in this study can be useful for the assessment of the developmental process of hand and mouth coordination in self-feeding.

Central fibroma in the ascending ramus of the mandible. Case report.

A case of central fibroma involving the mandible in a 58 year old woman is described. There was slight swelling of the left cheek and bone-hard bulging was detected on palpation but the patient had not complained of the swelling. The lesion was removed under general anaesthesia and then examined histopathologically. There was no sign of recurrence eleven months after the operation.

Maxillary protraction and chincap appliance treatment effects and long-term changes in skeletal class III patients.

The purpose of this study was to investigate the orthopedic effects of combined maxillary protraction appliance (MPA) and chincap therapy on growing Japanese girls and the posttreatment changes after growth is complete. To estimate the actual effects of treatment and posttreatment changes, we used a series of templates that had been constructed from semilongitudinal data of Japanese girls with normal occlusion. During treatment, forward movement of the maxilla with counterclockwise rotation, and backward and downward movement of the mandible with clockwise rotation and growth retardation were observed. The forward movement of the maxilla persisted until growth was complete. During the posttreatment period, the mandible maintained its improved position but showed excessive growth, which could be a rebound change. These results indicate that combined MPA and chincap treatment is effective for correcting skeletal Class III malocclusion.

[Relationships between tooth loss and electromyographic activities of masticatory muscles].

For purpose of evaluating the characteristic of electromyographic activities of masticatory muscles with front or molar tooth loss, electromyographic activities of masticatory muscles and mandibular movements during tooth tapping and gum chewing were investigated in each group of tooth loss, and were compared with those of control group. The results were as follows. 1. In reference to the group with front tooth loss, 1) On tooth tapping, each S.D. of the time parameters of electromyographic activities of jaw closing muscles especially masseter and posterior temporalis was small, and that of jaw opening muscle was large. 2) On gum chewing, offset of jaw closing muscles' activities especially masseter and anterior temporalis were delayed. 3) On both tooth tapping and gum chewing, there was no difference in mandibular movements from control group. 2. In reference to the group with molar tooth loss, 1) On both tooth tapping and gum chewing, each S.D. of the time parameters of electromyographic activities of jaw closing muscles was large. 2) On tooth tapping, S.D. of opening ratio was large. 3) On gum chewing, both S.D. of chewing cycle and opening ratio were large.

Biomechanical evaluation of the phases during simulated endotracheal intubation (ETI): pilot study on the effect of different laryngoscopes.

Endotracheal Intubation (ETI) is a common airway procedure used to connect the larynx and the lungs through a windpipe in patients under emergency situations. The process is carried out by a laryngoscope inserted into the mouth, used to help doctors in visualizing the glottis and inserting the tube. Currently, very few studies on objective evaluation of the biomechanics of the doctors during the procedure have been done. Additionally, these studies have been concentrated only on the overall performance analysis, without any segmentation, with a consequent loss of important information. In this paper, the authors present a preliminary study on a methodology to objectively evaluate and segment the biomechanical performance of doctors during the ETI, using surface electromyography and inertial measurement units. In particular, the validation has been performed by comparing three kinds of laryngoscopes involving an expert doctor. Finally, results are presented and commented.