Biomedical subjects

S Takatsuka

Publications and source records attributed to S Takatsuka.

At least 19 recordsLinked to original sources

PubMed2005

Changes in condylar long axis and skeletal stability after bilateral sagittal split ramus osteotomy with poly-L-lactic acid or titanium plate fixation.

This study was designed to assess skeletal stability after bilateral sagittal split ramus osteotomy (BSSO) and fixation with a poly-l-lactic acid (PLLA) plate, as compared to that after BSSO and fixation with a titanium plate, and to analyze the change in the condylar long axis after these procedures. The study group comprised 40 patients who had mandibular prognathism (20, titanium group; 20, PLLA group). The groups were randomized to show similar distributions of preoperative SNB. All patients underwent BSSO setback by the Obwegeser method. Fixation was done with bent titanium plates or bent PLLA plates, applied in a similar manner. Lateral, frontal, and submental-vertical cephalograms were analyzed preoperatively and postoperatively. The maximum mouth opening range and the incidence of temporomandibular disorders were also evaluated. There was no significant difference in the right condylar angle or width between the two groups, but the left condylar angle and width, gonial angle, and ramus inclination differed significantly between them (P<0.05). SNA, SNB, and ANB were similar in both groups. There was no significant difference between the groups in maximum mouth opening range or temporomandibular disorders. We conclude that the change in condylar angle after BSSO and fixation with a titanium plate is greater than that after BSSO and fixation with a PLLA plate, but skeletal stability related to the occlusion is similar for the two procedures.

Absorbable Implants↗

PubMed2005

Netherton syndrome in two Japanese siblings with a novel mutation in the SPINK5 gene: immunohistochemical studies of LEKTI and other epidermal molecules.

BACKGROUND: Netherton syndrome (NS) is a severe autosomal recessive disorder characterized by ichthyosiform erythroderma, bamboo hair and atopy. The disease is caused by mutations in the SPINK5 gene, which encodes a putative serine protease inhibitor, LEKTI (lymphoepithelial Kazal-type-related inhibitor). Previous studies have clearly shown a crucial role for LEKTI in skin barrier formation. OBJECTIVES: To identify pathogenic mutations in two Japanese siblings with NS, and further to investigate the consequences of the mutations at the protein level. METHODS: To screen for mutations in the SPINK5 gene, all of its exons and splice junctions were amplified by polymerase chain reaction and directly sequenced. In addition, immunohistochemical staining of LEKTI, desmoglein (Dsg) 1 and elafin was performed with their specific antibodies. RESULTS: Mutation analysis resulted in the identification of compound heterozygous mutations, Q713X and R790X, in the SPINK5 gene of both patients. The former one is a novel mutation. Immunohistochemical studies in one patient demonstrated a complete absence of LEKTI and a strong expression of elafin in the patient's skin. Dsg1 was normally expressed in our patient. CONCLUSIONS: In this report, we describe compound heterozygous mutations in the SPINK5 gene in two Japanese siblings with NS. The result of immunohistochemistry shows LEKTI deficiency and upregulation of elafin in the skin of one patient. Furthermore, our data indicate that degradation of Dsg1 does not always occur in NS.

Carrier Proteins↗

PubMed2005

Aggrecanase analysis of synovial fluid of temporomandibular joint disorders.

OBJECTIVES: To determine whether or not aggrecanase in synovial fluid can be used as a biochemical marker in the diagnosis of temporomandibular joint disorder (TMJD). MATERIALS AND METHODS: Forty-four samples of synovial fluid were obtained from 35 patients with internal derangement or osteoarthritis and 15 control samples from 10 asymptomatic volunteers. Aggrecanase in the synovial fluid was examined by immunoblotting. RESULT: The incidence of aggrecanase expression in TMJD group were significantly higher than that in the normal control group (P < 0.05). Those with severe OA and anterior disc displacement without reduction showed significantly high expression of aggrecanase compared with other disease subgroups (P < 0.05). CONCLUSION: These findings suggested that aggrecanase could be a potential biochemical marker for cartilage degeneration in the TMJD.

Adolescent↗

PubMed2001

Expression of matrix metalloproteinase-2 and -9 in synovial fluid of the temporomandibular joint accompanied by anterior disc displacement.

The purpose of this study was to determine whether or not matrix metalloproteinases (MMPs) in synovial fluid are helpful in the biochemical diagnosis of temporomandibular joint (TMJ) disorder (TMD). We examined the synovial fluid from 38 TMD patients with disc displacement and 20 volunteers by gelatin zymography and immunoblotting analysis to clarify the involvement of the joint pathology from the viewpoint of expression of MMPs. Two gelatinolytic enzymes, MMP-2 and -9, were detected in the samples. The incidences of expression, except for pro-MMP-2, in anterior disc displacement (ADD) without reduction (ADD w/o R) were significantly higher than in ADD with reduction (ADD w R) (P<0.05). Quantitative analysis showed that the degree of MMP-2 and -9 expression in ADD w/ o R were higher than in ADD w R. These data suggest that the presence or absence of disc reduction is a major turning point in the process of joint destruction, and these MMPs are useful as biochemical markers for TMD diagnosis.

Adolescent↗

PubMed2001

A model for temporomandibular joint disc repositioning surgery.

PURPOSE: The present study establishes a model of reversible anterior disc displacement using the rabbit craniomandibular joint (CMJ) and examines the period required for successful disc repositioning surgery. MATERIALS AND METHODS: The left CMJ was exposed surgically in 27 animals and a suture positioned at the posterolateral portion of the disc was pulled in an anterior direction causing 7 mm of anterior disc displacement. The suture was then fixed to the zygomatic arch. The changes in the CMJ were observed microscopically in 3 rabbits each at 2, 3, 5, 8, and 24 weeks. Another 12 rabbits underwent secondary disc repositioning surgery either the second and third week after disc displacement, and then 3 rabbits from each group were assessed microscopically at 5 to 6 weeks and 21 to 22 weeks after the first operation. Ten rabbits had a sham operation, and 2 served as unoperated controls. Histomorphometric evaluation included changes in morphology, cartilage, and disc condition. RESULTS: Progressive osteoarthritic change was induced by disc displacement. Articular disc perforation at 5 weeks after the first operation was accompanied by subchondral bone exposure. The CMJ morphology was almost normal in rabbits that underwent secondary disc repositioning 2 weeks after disc displacement. However, osteoarthritic changes and perforated discs similar to those in rabbits that did not undergo secondary disc repositioning were seen in animals in which repositioning was done in the third week. CONCLUSION: Artificial disc displacement in the rabbit causes osteoarthritic changes are reversible when the displaced disc is restored within after 2 weeks but not at 3 weeks.

Animals↗

PubMed2001

Plate fixation after mandibular osteotomy.

Skeletal asymmetry in patients who undergo orthognathic surgery is frequently associated with postoperative temporomandibular joint (TMJ) disorders caused by condylar rotation. This study was designed to elucidate the relation between changes in the condylar long axis and TMJ function after bisagittal split osteotomy (BSSO). A total of 42 patients with mandibular prognathism underwent BSSO. Split osseous fragments were secured by standard titanium plates in 22 patients; bent titanium plates were used to secure fragments in 20 patients. The angle of the bent plates was adjusted to avoid displacement of the condyle after osteotomy, as compared with condylar position on preoperative submental-vertical (S-V) cephalograms. The postoperative position of the condyle was assessed on X-ray film, and changes in TMJ function were evaluated. The condylar long axis differed significantly on X-ray film between patients using a standard titanium plate and those using a bent plate (P<0.05), and no sign of TMJ functional impairment was noted in the bent-plate group. Although the use of bent plates requires further study, maintenance of a suitable position of the condyle relative to the condylar axis is one of the conditions for a successful outcome of BSSO.

Analysis of Variance↗

PubMed2001

Somatosensory-evoked potential to evaluate the trigeminal nerve after sagittal split osteotomy.

OBJECTIVE: The purpose of this study was to assess the onset period of trigeminal nerve hypoesthesia during bilateral sagittal split osteotomy, with the use of the trigeminal somatosensory-evoked potential (TSEP). STUDY DESIGN: Subjects were 10 patients with mandibular prognathism who underwent setback surgery. Intraoperative TSEP was measured 4 times: just before the commencement of the surgery, immediately after the induction of general anesthesia; after the medial periosteal dissection of the alveolar neurovascular bundle; after the sagittal split of bone; and after semirigid fixation with a titanium miniplate with the use of a monocortical screw. Postoperative TSEP was measured after the start of postoperative weeks 2, 4, 12, and 24. Normal records of the TSEP wave comprised peak (13 ms), trough (16 ms), peak (22.7 ms), and trough (36 ms) (N1, P1, N2, P2, respectively). Trigeminal hypoesthesia was assessed by the latency of P1 and N2, because they indicated the most reproducible waveforms. RESULTS: The change in shape of the spectra indicated that prolonged latency was initiated on medial periosteal dissection and was extended further after the sagittal bone split and fixation. However, latency recovery was observed relatively quickly after the start of postoperative weeks 2 and 4. CONCLUSIONS: Trigeminal hypoesthesia appeared to be induced by direct injury to the alveolar nerve during the bone split or by compression injury after fixation. Accordingly, the occurrence of a long-lasting postoperative trigeminal sensory hypoesthesia seemed to depend on nervous involvement of the split surface, the manner of fixation, or the intraoperative care.

Adolescent↗

PubMed2000

Expression of matrix metalloproteinase-2 in osteoarthritic fibrocartilage from human mandibular condyle.

Matrix metalloproteinase (MMP)-2 is expressed in osteoarthritic cartilage and synovial fluid and is thought to be involved in the degradation of cartilage extracellular matrix. However, MMP-2 expression and osteoarthritic changes in internal derangement of the temporomandibular joint are unknown. In the present study, we have examined the histological relationship between osteoarthritic changes on articular cartilage with or without articular disc perforation, and MMP-2 expression, in 85 mandibular condyles from cadavers. The expression and tissue immunolocalization of MMP-2 in fibrocartilages from these condyles was examined histochemically. The Mankin grade of histological criteria for specimens with disc perforation was significantly higher than that of specimens without perforation. MMP-2 immunostaining was positive in the cytoplasm of chondrocytes and in their surrounding matrix. There was a linear correlation between MMP-2-positive cell rates and Mankin grade. Our data suggest that MMP-2 plays an important role in fibrocartilage degradation in internal derangement of the temporomandibular joint.

Aged↗

PubMed2000

Histological changes in the rabbit condyle following posterolateral disk perforation.

PURPOSE: To examine changes in condylar cartilage following perforation in the posterolateral region of the articular disk of the craniomandibular joint of a rabbit. MATERIAL AND METHODS: The circular perforation in the left joint of 25 female Japanese white rabbits measured precisely one-sixteenth of a disk. Histological examination, including the immunohistochemical proliferating cell nuclear antigen (PCNA) procedure, was performed on separate sets of five rabbits each 2, 4, 8, 12, and 24 weeks postoperatively. RESULTS: Microscopic examination revealed hypertrophy of the condylar cartilage with osteophyte formation up to 8 weeks after perforation. Proliferative activity then decreased near the condylar surface as the perforation flattened. Twenty-four weeks postoperatively, the condylar surface was found to be fibrous and flattened. Positive PCNA results in cartilage cells indicated proliferation following disk perforation which peaked in the 4th week and then decreased. CONCLUSION: Disk perforation was followed initially by hypertrophy of condylar cartilage, and later by degeneration of the condylar surface. Although osteoarthritic cartilage was found 24 weeks after perforation, degeneration decreased over time. This suggests that remodelling took place after the perforation.

Animals↗

PubMed2000

Temporomandibular joint morphology and disc position in skeletal class III patients.

INTRODUCTION: The purpose of this study was to investigate the relationship between temporomandibular joint (TMJ) morphology, including discal tissue and clinical symptoms in class III dentofacial deformity patients. MATERIAL AND METHODS: Forty-four patients were examined with lateral, frontal and axial cephalograms. They were divided into two groups, consisting of a class III symmetry and a class III asymmetry group. By using magnetic resonance imaging the 88 joints could be classified into four types on the basis of disc position and shape: anteriorly displaced disc, anterior type, fully-covered type and posterior type. Furthermore, TMJ morphology was measured tomographically in the sagittal plane. RESULTS: Anteriorly displaced discs in the asymmetry group (56.8%) occurred significantly more frequently than in the symmetry group (18.2%; p <0.05). TMJ symptoms (clicking, crepitus, closed lock, pain) were seen in 17/44 joints (38.6%) of the symmetry and 24/44 joints (54.5%) of the asymmetry group, for a total of 41/88 joints (46.6%). There were no differences in joint space ratio and condyle ratio. However, the fossa ratio on the deviation side was significantly higher than on the nondeviation side in the asymmetry group (p<0.05). CONCLUSION: The incidence of internal derangement in asymmetrical class III patients is higher than in symmetrical mandibular prognathism, and this difference is associated with a difference in TMJ morphology of both sides.

Adult↗

PubMed2000

Contribution of angiogenesis to the progression of colon cancer: possible inhibitory effect of angiogenesis inhibitor TNP-470 on tumor growth and hepatic metastasis.

The contribution of angiogenesis to tumor growth and hepatic metastasis of colorectal cancer was investigated by means of immunohistochemical study and in vitro and in vivo experiments. Colorectal cancer specimens from 30 patients with hepatic metastasis and 39 patients without hepatic metastasis were studied by staining with antibodies against factor VIII-related antigen. Microvessel count in patients with liver metastasis was significantly higher than in those without liver metastasis (p<0.005). The effect of TNP-470 was evaluated with in vitro and in vivo experiments using human colon cancer cell line, LM and the highly hepatic metastasis cell line, LM-H5. The effect of TNP-470 on the proliferation of the cancer cells and human umbilical vein endothelial cells (HUVECs) was examined. TNP-470 inhibited more sensitively the proliferation of HUVECs than cancer cells in vitro. IC50 was approximately 3 pg/ml in HUVECs and approximately 2 microg/ml in cancer cells. The effect of TNP-470 on the growth of xenografts and liver metastases by LM-H5 in nude mice was examined. TNP-470 (30 mg/kg) was administered by subcutaneous injection every third day for 4 weeks. TNP-470 inhibited both the growth of xenograft and the hepatic metastasis. The number of metastatic foci in the liver was 78.2+/-30.1 in the control group and 20.6+/-16.5 in the treated group. These results suggest that TNP-470 is a potent agent to inhibit tumor growth and hepatic metastasis of colon cancer.

Adult↗

PubMed1999

Condylar changes after contralateral mandibular osteotomy in the rabbit.

Following orthognathic surgery undesirable changes in the temporomandibular joints (TMJs) are noted sometimes. Altered stress on the condyle and surrounding tissue frequently causes morphological changes in the TMJ. The purpose of the present study was to assess these morphologic changes in a rabbit following mandibular osteotomy and the resulting mandibular body rotation. Adult male Japanese white rabbits (3 kg, 12-16 weeks old) were applied in this study. An experimental mandibular osteotomy was performed on the right side of the body of the mandible. The surgery includes vertical mandibular body osteotomy 5 mm in width after masseter muscle reflection. Then the anterior and posterior osseous segments were fixed with wire at previously made holes. As a result, the condylar medio-lateral width on the contralateral (left) side was significantly larger than that of the ipsilateral side 2 weeks postoperatively (p < 0.05). There were significant differences in the angle between the right and the left condylar heads 4 weeks postoperatively (p < 0.05). The present experimental study demonstrated morphological changes in the contralateral TMJ caused by unilateral mandibular osteotomy. Postoperative morphological changes implied that there is a process of biological adaptation in the rabbit TMJ.

Adaptation, Physiological↗

PubMed1998

New cephalometric images with a workstation. A preliminary report.

OBJECTIVE: This study was designed to test the feasibility of several types of enhancements for cephalometric computed radiographs through use of the Fuji Computed Radiography system (Fuji Photo Film Corp., Tokyo, Japan). STUDY DESIGN: The material consisted of four lateral cephalograms made with the Fuji Computed Radiography system that were enhanced by varying the gradient levels before processing by means of both A-type (straight gradation) curves and workstation-type (peaked) curves. The four workstation-type images were set with optical densities at the peak of the curve at 1.5, 1.7, 1.9, and 2.1. Ten observers evaluated eight anatomic landmarks comparing pairs of workstation-type images. The best workstation-type image was then compared with the A-type image for the same landmarks. RESULTS: For the four workstation-type images the best visualization of the anatomic landmarks was seen with workstation-type image 3, which had a maximum optical density of 1.9. Image 3 was also superior to the results of A-type image processing for most of the landmarks. CONCLUSION: Image enhancement with the application of a computed radiography system is effective for study of lateral cephalograms.

Cephalometry↗

PubMed1997

The assessment of trigeminal sensory nerve paraesthesia after bilateral sagittal split osteotomy: modified somatosensory evoked potentials recording method.

Trigeminal neurosensory impairment is frequently observed following orthognathic surgery. The purpose of the present study is to visualize the degree of trigeminal nerve impairment following bilateral sagittal split osteotomy (BSSO). Twenty patients who underwent BSSO were in the present study. To record the modified somatosensory evoked potentials (SEP), two electrostimulation clips were applied. One clip was placed on the mucous surface of the lower lip and the other was placed on the skin surface. Each contact surface contained a separate 2 mm diameter silver anode and cathode attached to a 5 x 15 mm basement plate. The results obtained using this method revealed that complete recovery from neural impairment was observed in 7 cases (36.8%) on the right operative side and 4 (20.0%) on the left side at 6 months postoperatively. A definite delay in latency was observed on the left operative side at all the examination periods. The recovery period evaluated by the SEP method was longer than that of the objective two-point discrimination thresholds. Clinical records obtained showed considerable implications for trigeminal nerve function after BSSO.

Adolescent↗

PubMed1997

Increased sialyl Lewis A expression and fucosyltransferase activity with acquisition of a high metastatic capacity in a colon cancer cell line.

A human colon cancer cell line, OCUC-LM1(LM), was established from a liver metastasis in our laboratory. Intrasplenic injection of LM into nude mice was repeated three and five times, and the daughter cell lines were designated as LM-H3 and LM-H5 respectively. The level of sialyl Lewis A (SLA) in the supernatant of LM-H3 and LM-H5 was 3 and 4.5 times higher than that of LM respectively. Flow cytometric analysis of SLA expression showed that the peak channel for LM was 113; for LM-H3, 126; and for LM-H5, 146. The mean fluorescence intensity of LM was 102.3 +/- 43.5; for LM-H3, 126.2 +/- 28.4; and for LM-H5, 144.8 +/- 23.4. In endothelial cell adhesion assays, the percentages of adherent LM-H3 and LM-H5 cells were significantly higher than for LM. The activity of alpha1-->4 fucosyltransferase was higher in LM-H3 and LM-H5 than in LM, but there was no difference in alpha2-->3 sialyltransferase activities for type 1 chain among the cell lines. Our results suggest that SLA expression is associated with acquisition of a high capacity for liver metastasis of colon cancer; increased SLA expression is due mainly to increased fucosyltransferase activity.

Animals↗

PubMed1996

Prognostic value of vascular endothelial growth factor expression in gastric carcinoma.

BACKGROUND: Many studies have shown that angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Recently, several angiogenic factors have been identified. Vascular endothelial growth factor (VEGF) is thought to be one such angiogenic factor and is also thought to be a selective mitogen for endothelial cells. We investigated the correlation between the expression of VEGF and the progression of gastric carcinoma. METHODS: One hundred twenty-nine specimens resected from patients with gastric carcinoma were investigated by staining with a polyclonal antibody against VEGF. Correlations between the expression of VEGF, microvessel density, and various clincopathologic factors were studied. RESULTS: Microvessel density, determined by immunostaining for Factor VIII related antigen, was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. VEGF positivity was correlated with vessel involvement, lymph node metastasis, and liver metastasis. Moreover, patients with VEGF-positive tumors had a significantly poorer prognosis than those with VEGF-negative tumors. Multivariate analysis indicated that the expression of VEGF is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased among patients with VEGF-positive tumors. CONCLUSIONS: The expression of VEGF may be a good prognostic indicator for patients with gastric carcinoma and may also be useful as a predictor of the mode of recurrence in patients with gastric carcinoma.

Adult↗

PubMed1996

Histologic evaluation of auricular cartilage grafts after discectomy in the rabbit craniomandibular joint.

PURPOSE: The clinical use of auricular cartilage grafting after discectomy has been reported as a treatment in the terminal stage of internal derangement of the temporomandibular joint (TMJ). Although the occurrence of fibrous adhesions has been observed in such grafted joints, the exact tissue reaction to the graft is still not understood. The purpose of this study was to evaluate the histologic changes after discectomy and auricular cartilage grafting in the rabbit craniomandibular joint (CMJ). MATERIALS AND METHODS: Unilateral discectomy of the left CMJ was performed in 28 Japanese white rabbits. Auricular cartilage harvested from the ipsilateral ear was grafted as a disc replacement in 14 animals (Group C), and the other 14 underwent wound closure immediately after discectomy (Group B). Two other rabbits (Group A) served as nonsurgically treated controls. Two rabbits from each experimental group were killed at 2, 4, 6, 8, 10, 12, and 24 weeks postoperatively. Microscopic observation of the specimens was performed in the parasaggital plane. RESULTS: Complete resorption of the cartilage layer on the articular surface was observed within 4 weeks postoperatively in group B. Regeneration of a fibrous cartilage layer was observed in this group after 6 weeks, but the postoperative degenerative changes were so severe that the surface of the condyle and eminence was flattened. In contrast, the degenerative changes were milder in group C, although the grafted cartilage showed perforation and fragmentation from the sixth postoperative week onward. The condylar shape and cartilage layer were well preserved at all times. CONCLUSIONS: These results suggest that the structure and function of the condyle may be preserved by auricular cartilage grafting after discectomy. However, the problems of adhesion and fragmentation need to be addressed.

Animals↗

PubMed1996

Thymidine phosphorylase/platelet-derived endothelial cell growth factor expression associated with hepatic metastasis in gastric carcinoma.

It is known that angiogenesis plays an important role in the growth and metastasis of solid tumours. Several angiogenic factors have been identified and platelet-derived endothelial cell growth factor (PD-ECGF) is thought to be one such factor. Recently, it was reported that thymidine phosphorylase (dThdPase) is identical to PD-ECGF. Using immunohistochemical staining with an anti-dThdPase antibody, we investigated the correlation between dThdPase expression and the microvessel density in 120 gastric carcinomas. The microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in dThdPase-positive tumours than in dThdPase-negative tumors. There was a significant correlation between dThdPase expression and the increment of microvessel density. Moreover, regarding distant organ metastasis, the frequency of hepatic metastasis was significantly higher (P < 0.01) in patients with dThdPase-positive tumours than in those with dThdPase-negative tumors. In summary, it was suggested that dThdPase expression is closely associated with the promotion of angiogenesis and hepatic metastasis in gastric carcinoma.

Adult↗