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Biomedical subjects

Y Isshiki

Publications and source records attributed to Y Isshiki.

At least 37 records · Page 2Linked to original sources
PubMed1998

Relationships between mandibular symphysis morphology and lower incisor inclination in skeletal class III malocclusion requiring orthognathic surgery.

The purpose of this study is to clarify symphysis morphological characteristics in skeletal class III malocclusion requiring orthognathic surgery and their relationships with symphysis morphology and inclination of the long axis of the lower incisor. The materials were pretreatment lateral cephalometric radiographs from 50 subjects diagnosed as requiring orthognathic surgery. Controls were 30 adults with normal occlusion and well-balanced faces. Detailed cephalometric measurements on the mandibular symphysis (angular, linear and proportional measurements) were recorded and analyzed statistically. In the surgical group, the long axis of the lower incisor demonstrated a significant lingual inclination in relation to the mandibular plane and symphysis. Moreover, because the symphysis demonstrated lingual inclination everywhere except in the basal bone region in relation to the mandibular plane, the curvature between the alveolar and the basal bone region was significantly smaller than that of normal occlusion group. The symphysis labial external surface in the alveolar and basal bone regions demonstrated lingual inclination in relation to the mandibular plane, however, there was no difference in curvature. Small mean values were obtained for Pt.B width, Pog width, and Sym height. Significant differences were observed only in Pt.B width. In both the surgical and normal occlusion groups, a significant correlation was observed between the inclination of the long axis of the lower incisors and symphysis inclination. In the basal bone region, however, there was no significant correlation.

Adult↗
PubMed1998

The effects of retraction forces applied to the anterior segment of orthodontic arch wires: differences in wire deflection with wire size.

Orthodontic arch wire deflection was studied in relationship to retraction forces applied to arch wires during anterior retraction with sliding mechanics. Two different sizes of orthodontic stainless steel arch wires (SS wires) .016" x .022" and .019" x .025", were examined. Retraction forces were generated using an elastic polymer material to measure arch wire deflection and applied to the arch wires by a commonly-used anterior retraction device with power chains hooked from the first molar areas to the pre-welded posts at distal site of the lateral incisors. The force application caused both the .016" x .022" and the .019" x .025" arch wires to deflect. The amount of deflection increased almost in proportion to the retraction force applied. With the same retraction force applied, the amount of deflection of the .019" x .025" wire was approximately 47.1% of that of the .016" x .022" wire.

Dental Arch↗
PubMed1997

A study of the growth changes in the maxillofacial skeleton of females with reversed occlusion: investigation by means of lateral x-ray cephalogram.

321 females with reversed occlusion from the ages of 6 to 20 were classified into 15 groups according to chronological age, and the changes of maxillofacial skeleton accompanying growth were investigated. Lateral cephalometric roentgenogram before treatment of the subjects were used for analyses and measurements of maxillofacial skeleton and overjet. The cephalometric analysis was standardized on the S-N plane, and 5 angular items and 6 linear distances were examined. The results of the investigation are summarized as follows: (1) angle ANB, the relationship between the upper and lower jaws, deteriorated to a minus degree from the age of 9 and became -3.3 degrees at the age of 14. Skeletal convexity became negative from the same age and was -7.3 degrees at the age of 14. Thus, the abnormal skeletal features progressed in this condition. (2) The Ar-Gn distance measurement gradually increased from the age of 6 to 18. The increase was 16.2 mm from 7 to 12, an increase of 3.2 mm yearly. (3) A high correlation (r = 0.99) was observed between angle ANB and Convexity. As well, a high coefficient of correlation (r = 0.87) was observed between skeletal convexity and soft tissue convexity. The change in soft tissue convexity may occur 3-4 years later than that of skeletal convexity. (4) The growth curve of Ar-Gn became a logistic curve with the point of deflection at the age of 10.87. The growth curves of S-Gn and N-Me became logistic curves in the same way.

Adolescent↗
PubMed1997

Soft laser irradiation effects on pain reduction in orthodontic treatment.

The effects of soft laser (low reactive level laser) on reduction of pain while undergoing orthodontic treatment was examined in this study. These patients were randomly separated into 3 groups: non-treated control group (CG), blind irradiation group (BG), and laser irradiated group (LG). The effect of laser irradiation on reduction in pain was analyzed by a questionnaire given to patients who had been wired with an edgewise appliance of a multi-bracket system for orthodontic therapy. Just after application of the initial wire, LG patients were irradiated with the soft laser from the labial and lingual sites for a total of one minute. Reduction in pain was found in some patients who had been irradiated. In particularly, delay in the pain appearance was noted as compared to the other two control groups.

Adolescent↗
PubMed1997

A dynamic study of the effect on the maxillofacial complex of the face bow: analysis by a three-dimensional finite element method.

In order to investigate the effects of a face bow on the maxillofacial complex, we applied an analysis by a finite element method. To create a skull model, we measured an adult skull sample, and constructed a left lateral model without a mandible with 11 bones of 11 types, 30 sutures, and 3 synchondroses. The numbers of elements and nodes in the model were 1,207 and 1,539, respectively. The numbers of elements in the face bows used were 16 for the short type and 22 for the long one, respectively. Both of them were directly connected to the first molar tooth. To establish the constraining conditions, a symmetrical condition at the center of the model was chosen, and the basal part of the occipital bone was completely fixed. Each 1 kg loading was applied in three directions: 30 degrees post-superior, 0 degree posterior, and 30 degrees post-inferior. The results from this face bow loading experiment showed that the direction of displacement and the stress distribution were significantly different among the kinds of the face bows and the loading directions. For the short type face bow, simple compression appeared due to the post-superior loading and bending deformation due to the posterior and post-inferior ones. For the long type face bow, some bending deformations appeared, including anterior-elongation and posterior compression due to the post-superior loading. Post-inferior bending due to posterior loading and post-inferior bending and inferior displacement due to the post-inferior loading also appeared. Thus it is feasible to dynamically control the maxillofacial complex form by changing the type of the face bow and the direction of the loading traction.

Adult↗
PubMed1996

Effects of fasting and refeeding on structures of the intestinal villi and epithelial cells in White Leghorn hens.

1. The fine structural alterations of villi and epithelial cells in each part of the small intestine were investigated in layer-type hens fasted for 12 h to 20 d or refed for one day after each fasting period. 2. Within the first 24-h-fasting, villi of the duodenum showed a remarkable reduction in height and those of the jejunum revealed a gradual decrease; such a significant reduction of the villus height was not obtained in the ileum. After 36-h-fasting, villus height in each part gradually decreased with days of fasting. 3. All intestinal villus heights increased after only 1-d-refeeding of various kinds of diets following 3-, 10-, or 20-d-fasting. The duodenum especially rapidly recovered even after long-term fasting of 20 d but the ileum showed very slow recovery, suggesting that the ileum seems to be inactive in absorptive function. 4. These variable alterations of villus height in the proximal intestine suggest that the higher intestinal absorptive ability is under the normal feeding, the more rapidly villus height is influenced by nutritional conditions. 5. Cell area and cell mitosis decreased after fasting, the latter showing a marked reduction. However, in spite of a remarkable decrease of cell mitosis in the proximal intestine after fasting, refeeding activated cell renewal and it soon reached control levels, demonstrating that the villus height mainly varied with the numbers of epithelial cells. 6. In the epithelial cells of the proximal intestine in chickens fasted for 20 d, large lysosomal autophagous vacuoles including mitochondria and dense bodies were observed. These were reduced in size by refeeding for only one day, suggesting that fasting may cause intracellular digestion through lysosomal autophagy. 7. These results lead to the conclusion that long-term for force moulting is possible, that a high protein and high energy diet can be fed immediately after fasting and that a cell undergoing lysosomal autophagy in normal chickens indicates undernutrition.

Animals↗
PubMed1996

The O polysaccharide chain of the lipopolysaccharide from Vibrio cholerae O76 is a homopolymer of N-[(S)-(+)-2-hydroxypropionyl]-alpha-L-perosamine.

Chemical and serological studies of LPS from Vibrio cholerae O76 (O76) were performed. The LPS of O76 contained D-glucose, D-galactose, L-glycero-D-manno-heptose, D-fructose, D-glucosamine, D-quinovosamine (2-amino-2,6-dideoxy-D-glucose) and L-perosamine (4-amino-4,6-dideoxy-L-mannopyranose). The sugar composition of the LPS from O76 was quite similar to that of LPS from V. cholerae O1 with the exception of the presence of a small amount of D-galactose in the LPS of O76. However, perosamine, a major sugar component of the LPS from O76, was in the L configuration in contrast to the D configuration of the perosamine in the LPS of V. cholerae O1. The L-perosamine was N-acylated with an (S)-(+)-2-hydroxypropionyl group in the LPS from O76. Structural analysis by NMR spectroscopy, as well as GC/MS, revealed that the O polysaccharide chain of the LPS from O76 was an alpha(1-->2)-linked homopolymer of N-[(S)-(+)-2-hydroxypropionyl]-L-perosamine. The serological cross-reactivity between the LPS of O76 and the LPS from other strains, such as V. cholerae O1 (Ogawa and Inaba O forms), Vibrio bio-serogroup 1875 (Original and Variant strains), V. cholerae O140 (Hakata) and Yersinia enterocolitica O9, was examined in passive haemolysis tests with sheep red blood cells that had been sensitized with LPS and antisera raised against whole cells of these bacteria. The latter six strains have in common the O antigen that includes Inaba antigen factor C, in addition to their own O-antigenic factors. Thus, they crossreact serologically. The O polysaccharide chains of the LPS of these six trains are known to consist exclusively of alpha(1-->2)-linked D-perosamine homopolymers and differences are found only among the N-acyl substituents. In passive haemolysis tests, the LPS of O76 did not cross-react serologically with any of the other LPS examined. Thus, the results obtained in this study support the hypothesis that Inaba antigen factor C, associated with the O antigens of these six strains, which include V. cholerae O1, is related substantially and exclusively to their alpha(1-->2)-linked homopolymers of N-acylated D-perosamine, and not to such homopolymers of N-acylated L-perosamine.

Acetylation↗
PubMed1996

Extraction and characterization of the smooth-type lipopolysaccharide from Fusobacterium nucleatum JCM 8532 and its biological activities.

The lipopolysaccharide (LPS) of Fusobacterium nucleatum JCM 8532 was isolated by hot-phenol water extraction. Most of the LPS was extracted in the phenolic phase and shown to be the smooth-type, whereas the aqueous phase contained mainly rough-type LPS. The chemical composition of the LPS was similar to that reported in other studies, but D-quinovosamine, which may be a major component of O-antigenic polysaccharide, and 3-deoxy-D-manno-2-octulosonic acid (Kdoi) were detected for the first time by gas chromatography-mass spectrometry. The biological activities of smooth-type LPS, including limulus activity, lethal toxicity, pyrogenicity, and B lymphocyte mitogenicity, were comparable to those of entero-bacterial LPS. Smooth-type LPS inhibited the cell growth and DNA synthesis of adult and fetal human gingival fibroblasts in a dose-dependent manner, suggesting that LPS may play a role in the occurrence of human gingivitis.

Adult↗
PubMed1996

An N-[(R)-(-)-2-hydroxypropionyl]-alpha-L-perosamine homopolymer constitutes the O polysaccharide chain of the lipopolysaccharide from Vibrio cholerae O144 which has antigenic factor(s) in common with V. cholerae O76.

Chemical and serological studies were performed with the lipopolysaccharide (LPS) from Vibrio cholerae O144 (O144). The LPS of O144 contained D-glucose, D-galactose, L-glycero-D-manno-heptose, D-fructose, D-quinovosamine (2-amino-2,6-dideoxy-D-gluco-pyranose) and L-perosamine (4-amino-4,6-dideoxy-L-manno-pyranose). The perosamine, a major component sugar of the LPS from O144, was in an L-configuration, as is also the case in the LPS from V. cholerae O76 (O76), in contrast to the D-configuration of the perosamine in the LPS of V. cholerae O1. A structural analysis revealed that the O polysaccharide chain of the LPS from O144 is an alpha(1-->2)-linked homopolymer of (R)-(-)-2-hydroxypropionyl-L-perosamine. The serological cross-reactivity between O144 and O76 was clearly revealed by cross-agglutination and cross-agglutinin absorption tests with whole cells, as well as by passive hemolysis tests with sheep red-blood cells that had been sensitized with the LPS from O144 and O76. In contrast, in passive hemolysis tests, the LPS of O144 did not cross-react serologically with the LPSs from other strains such as V. cholerae O1 (Ogawa and Inaba), V. cholerae O140, Vibrio bio-serogroup 1875 (Original and Variant) and Yersinia enterocolitica O9. The LPSs from these strains consist of O polysaccharide chains composed of alpha(1-->2)-linked homopolymers of D-perosamine with various N-acyl groups, and they share the Inaba antigen factor C of V. cholerae O1 in common. The results obtained in this study demonstrate that the absolute configuration of the perosamine residue in homopolymers plays a very important role in the expression of the serological specificity of the Inaba antigen factor C of V. cholerae O1.

Agglutination Tests↗
PubMed1996

Long-term stability following surgical orthodontic treatment of mandibular prognathisms: investigation by means of lateral X-ray cephalogram.

The purpose of this study was to investigate the long-term stability of jaw relations and occlusion following surgical orthodontic treatment of mandibular prognathisms and skeletal openbites. Subjects consisted of fifteen adult patients. Ten patients underwent the sagittal split ramus osteotomy (SSRO) of the mandible and five patients underwent two jaw surgery (Le Fort I osteotomy of the maxilla and SSRO of the mandible). They were observed over five years after the end of active treatment, and lateral X-ray cephalograms were taken at each stage. In the SSRO group, pogonion was retrograded an average of 8.7mm due to the operation and it was further replaced 0.4mm backward after the end of active treatment. Although the vertical distance between nasion and menton decreased 2.9mm between the operative period, it increased 1.8mm after the end of active treatment. On the other hand, in the two jaw surgery group, point A was advanced 4.0mm forward and < SNA increased 3.1 degrees between the operative period. Pogonion was retrograded 11.4mm between the same period, but moved 0.7mm forward after the end of active treatment. A comparison of the osteosynthesis methods revealed that pogonion in the wiring group was retrograded 8.3mm backward between the operative period, but moved 2.1mm forward during the postsurgical orthodontic treatment. Pogonion in the rigid group was retrograded 12.6mm backward between the operative period, but moved 1.6mm forward during the postsurgical orthodontic treatment. However, both groups were stabilized completely after the end of active treatment. A comparison of the differences in the orthodontic treatment method revealed that < Ul-SN in the extraction group inclined 8.3 degrees lingually during presurgical orthodontic treatment, but it tipped 7.0 degrees labially during the postsurgical orthodontic treatment and inclined 3.4 degrees lingually after the end of active treatment. < Ul-SN in the non-extraction group inclined 5.5 degrees lingually during the presurgical orthodontic treatment, but it tipped 2.0 degrees labially during the postsurgical orthodontic treatment and inclined 1.9 degrees lingually after the end of active treatment.

Adult↗
PubMed1995

Immunochemistry of group A and Inaba C antigen factors constituting the O antigen of O1 Vibrio cholerae.

Serological cross-reactivity among intact lipopolysaccharides (LPS) from O1 Vibrio cholerae Inaba O-form (Inaba), Yersinia enterocolitica O9 (O9), non-O1 V. cholerae serogroup Hakata (Hakata) and Vibrio bio-serogroup 1875 Variant (1875 Variant) (all of which share Inaba antigen factor C), as well as a total of six kinds of chemically modified LPS (three from O9 and three from Inaba) was demonstrated by passive hemolysis and passive hemolysis inhibition by using these LPS as antigen for sensitizing sheep red blood cells and as inhibitor. These intact as well as chemically modified LPS contained, in their O polysaccharide chain, alpha(1-->2)-linked linear perosamine (4-amino-4,6-dideoxy-D-manno-pyranose) homopolymers with different N-acyl groups: their acyl groups comprise 3-deoxy-L-glycero-tetronyl (Inaba LPS), formyl (O9 LPS), 3-hydroxypropionyl (1875 Variant LPS), acetyl (Hakata LPS and artificially introduced into Inaba and O9 LPS), propionyl and butyryl (both artificially introduced into Inaba and O9 LPS) groups. N-Deacylation of the alpha(1-->2)-linked N-(3-deoxy-L-glycero-tetronyl)perosamine homopolymer of Inaba and the N-formyl one of O9 LPS resulted in virtual elimination of their serological reactivity with both homologous and heterologous antisera. Furthermore, when the resultant NH2 groups of the N-deacylated perosamine homopolymers of both LPS were N-acylated with acetyl, propionyl or butyryl groups, they markedly recovered both of their serological reactivities. These results are compatible with the interpretation that the Inaba antigen factor C possessed by the four bacteria is substantially related to the common presence of N-acyl groups, regardless of their identity, residing in the perosamine residues constituting the O polysaccharide chain of their LPS. It was also indicated that the group antigen factor A of O1 V. cholerae is substantially related to the 3-deoxy-L-glycero-tetronyl groups residing in the perosamine homopolymer of Inaba LPS.

Antibodies, Bacterial↗
PubMed1994

Biological activities of lipopolysaccharide isolated from Vibrio cholerae O139, a new epidemic strain for recent cholera in Indian subcontinent.

Biological activities of lipopolysaccharide (LPS) isolated from Vibrio cholerae O139, a new causative agent for recent cholera epidemic in Indian subcontinent, were investigated in comparison with those of LPS from O1 V. cholerae. V. cholerae O139 LPS exerted mitogenic activity, lethal toxicity and Shwartzman reaction to the same extent as those observed for O1 V. cholerae LPS, although these activities except for lethal toxicity were obviously lower than those of Salmonella typhimurium LT-2 LPS used as a reference. It was, therefore, suggested that O139 LPS does not contribute to the high infective and pathogenic potentials of the V. cholerae O139 strain as in the case of O1 V. cholerae.

Animals↗
PubMed1993

O-antigenic lipopolysaccharide of Vibrio cholerae O139 Bengal, a new epidemic strain for recent cholera in the Indian subcontinent.

Lipopolysaccharide (LPS) from Vibrio cholerae O139 Bengal contained colitose (3,6-dideoxy-L-galactose) in addition to glucose, L-glycero-D-manno-heptose, fructose, glucosamine and quinovosamine in its polysaccharide and only glucosamine in lipid A, while perosamine, a characteristic component sugar of V. cholerae O1 LPS, was absent. 3-Hydroxydodecanoic, tetradecanoic and hexadecanoic acids as ester-bound fatty acids and 3-hydroxytetradecanoic acid as amide-bound fatty acid were identified in the lipid A. A very high serological specificity of O139 LPS distinct from that of O1 V. cholerae was demonstrated by passive hemolysis and passive hemolysis inhibition tests by using the LPS either as antigen for sensitizing sheep red blood cells or as inhibitor in the latter test.

Carbohydrates↗
PubMed1993

N-3-hydroxypropionyl-alpha-D-perosamine homopolymer constituting the O-chain of lipopolysaccharides from Vibrio bioserogroup 1875 possessing antigenic factor(s) in common with O1 Vibrio cholerae.

A structural study was performed by 13C-n.m.r. spectroscopy and methylation analysis of the O-chain of lipopolysaccharide (LPS) from Vibrio bioserogroup 1875 possessing antigenic factor(s) in common with O1 Vibrio cholerae. It was demonstrated to contain a linear homopolymer of (1-->2)-linked N-3-hydroxypropionyl-alpha-D-perosamine [4-(3-hydroxypropanamido)-4,6-dideoxy-alpha-D-mannopyranose], which is very similar to, but not identical with, both (1-->2)-linked linear N-3-deoxy-L-glycero-tetronyl(S-2,4-dihydroxybutyryl)-alpha-D - perosamine homopolymer and (1-->2)-linked linear N-acetyl-alpha-D-perosamine homopolymer which constitute the O-chains of O1 V. cholerae and non-O1 V. cholerae bioserogroup Hakata LPS respectively.

Acetylation↗
PubMed1993

Occurrence of 2-O-methyl-N-(3-deoxy-L-glycero-tetronyl)-D-perosamine (4-amino-4,6-dideoxy-D-manno-pyranose) in lipopolysaccharide from Ogawa but not from Inaba O forms of O1 Vibrio cholerae.

A structural study by GC-MS, methylation analysis, and 1H and 13C NMR was carried out on alpha (1-->2)-linked linear N-(3-deoxy-L-glycero-tetronyl)-D-perosamine homopolymer constituting the O-polysaccharide chain of lipopolysaccharide from O1 Vibrio cholerae Ogawa and Inaba O forms. Occurrence of 2-O-methyl-N-(3-deoxy-L-glycero-tetronyl)-D-perosamine was demonstrated at the non-reducing terminus of the perosamine-homopolymer of lipopolysaccharide from the Ogawa O form in contrast to the presence of N-(3-deoxy-L-glycero-tetronyl)-D-perosamine at the nonreducing terminus for the Inaba O form.

Carbohydrate Conformation↗