A classification and characterization of skeletal class III malocclusion on etio-pathogenic basis.

Skeletal Class III malocclusion has been classified by the position of the maxilla, the mandible, the maxillary alveolus, the mandibular alveolus and vertical development. This morphologic approach is simple and useful for clinical use, but it is insufficient to permit understanding of the pathophysiology of dysmorphoses. The authors hypothesized that there were different patterns of mutual relation of the skeletal components contributed to pathologic equilibrium of skeletal Class III malocclusion. The purpose of this study is 3-fold; (1) to classify skeletal Class III malocclusion in subgroups that can show the architectural characteristics of the deformity, (2) to analyze the craniofacial architecture of each subgroup on etio-pathogenic basis, and (3) to characterize and visualize the pattern as a prototype. Materials used in this study were lateral cephalograms of 106 untreated skeletal Class III malocclusion adults, which were analyzed with modified Delaire's analysis. Linear and angular measurements of each subject were obtained and cluster analysis was used for grouping. In the results, seven groups were identified and presented as prototypes, which could show the etio-pathology of the skeletal architecture. The classification and description presented in this study is thought to be biologic and helpful in the understanding of skeletal Class III malocclusion and treatment planning.

MRI examination of the TMJ after surgical treatment of condylar fractures.

The position of discs in 20 adult patients whose unilateral condylar fractures were treated by open reduction was investigated by means of magnetic resonance imaging. In four (20%) of the 20 cases, the disc was anteriorly displaced in both the closed mouth and open mouth positions. Three of the four cases had a high condylar neck fracture with dislocation and one had a high condylar neck fracture with displacement. The results of this study showed that repositioning the dislocated condyle did not always lead to anatomical restoration of the joint structures.

A comparison of the stability of miniplate with bicortical screw fixation after sagittal split setback.

OBJECTIVE: The objective of this study was to decide whether use of bicortical screw fixation provides sufficient stability to dispense with intermaxillary fixation. STUDY DESIGN: Thirty consecutive patients who had undergone surgical setback of the mandible by means of bilateral sagittal split ramus osteotomies were studied. Group 1 (15 patients) had miniplate fixation with intermaxillary fixation for 6 weeks, and group 2 (15 patients) had bicortical screw fixation and immediate postoperative function. The 2 groups were evaluated radiographically for postsurgical changes of pogonion in the early (6 weeks) phase. RESULTS: The results showed that there were no significant differences between the 2 groups. Overall, there was good stability in both groups. CONCLUSION: The use of bicortical screw fixation after sagittal split setback of the mandible provides sufficient stability to dispense with intermaxillary fixation.

Mandibular anatomy related to sagittal split ramus osteotomy in Koreans.

Sagittal split ramus osteotomy (SSRO) is one of the surgical techniques used to correct mandibular deformities. In order to prevent many surgical anatomical problems, we observed the anatomical structures related to SSRO. In dry mandibles of Koreans, lingular tips were located somewhat posteriorly and superiorly on the mandibular ramus. On the coronal sections of mandible, the mean cortical width of facial cortex was increased toward the ramus region while the lingual cortex was thinnest in the ramus region. On the same sections, all the fusion points of the buccal and lingual cortical plate were located above the mandibular lingula and beneath the mandibular notch. So, performing the SSRO on Koreans, medial horizontal osteotomy should be done through the superior aspect of the mandibular lingula. The cut line is extended 5-8 mm posterior to the mandibular lingula to preserve sufficient cortical width to strengthen the involved osseous segments and reduce possible surgical complications.

Sequences within the VP6 molecule of bluetongue virus that determine cytoplasmic and nuclear targeting of the protein.

Genome segment 9 of bluetongue virus serotype 10 encodes the minor protein VP6. The protein is abundant with basic residues particularly in two regions of the carboxy half of the molecule. A series of amino- and carboxy-terminal deletion mutants was expressed in mammalian cells by using a vaccinia virus T7 polymerase-driven transient expression system, and the intracellular fate of the products was monitored by both immunofluorescence staining and cell fractionation techniques. Data obtained indicated clearly that VP6 has nuclear transportation signals which may be correlated with positively charged domains of the molecule. In the intact molecule, though, these signals are masked and the protein is retained in the cytoplasm. The biochemical and immunofluorescence data obtained indicate that sequences in the region of residues 33 to 80 of the 328-amino acid protein are required for the retention of VP6 within the cell cytoplasm while amino acids 303 to 308 in the carboxy-terminal half of the molecule appear to possess nuclear localization capabilities.

Characterization of functional human erythrocyte-type glucose transporter (GLUT1) expressed in insect cells using a recombinant baculovirus.

The human erythrocyte-type glucose transporter (GLUT1) has been abundantly expressed in insect cells by using a recombinant baculovirus. At 4 days after infection with the virus, the insect cell-surface and intracellular membranes were found to contain greater than 200 pmol of D-glucose-sensitive binding sites for the transport inhibitor cytochalasin B per mg of protein. The characteristics of binding were identical with those of the erythrocyte transporter, although the two proteins differed substantially in apparent Mr, probably as a result of glycosylation differences.

Increase in beta-N-Acetylglucosaminidase Activity during Germination of Cotton Seeds.

A marked increase in beta-acetylglucosaminidase (2-acetamido-2-deoxy-beta-d-glucoside acetamidodeoxyglucohydrolase, EC 3.2.1.30) activity was observed in the germinating cotyledon of cotton seeds. The enzyme was isolated from cotton seedlings and purified to study its physiological function in the germination of cotton seeds. The purification procedure involves ammonium sulfate fractionation, ion-exchange chromatography, gel filtrations, and concanavalin A-Sepharose 4B chromatography, and the purified beta-N-acetylglucosaminidase was shown to be homogeneous by disc electrophoresis. The molecular weight was estimated to be about 125,000 by gel filtration. The enzyme hydrolyzed both p-nitrophenyl-N-acetyl-beta-d-glucosamine and p-nitrophenyl-N-acetyl-beta-d-galactosamine. When p-nitrophenyl-N-acetyl-beta-d-glucosamine was used as substrate, K(m) and V(max) were 0.625 nanomolar and 228 moles per minute per milligram, respectively, and optimum activity was at pH 5.6. The enzyme liberated beta-linked N-acetyl-glucosamine from chitin, ovalbumin, and pronase-digested wheat germ lectin.