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Biomedical subjects

Mitsuo Ochi

Publications and source records attributed to Mitsuo Ochi.

At least 145 records · Page 8Linked to original sources
PubMed2002

Treatment of growth plate injury with autogenous chondrocytes: a study in rabbits.

We designed this study to investigate transplantation of autogenous chondrocytes cultured in atelocollagen gel to treat the injured growth plate. An experimental model of growth arrest was made by resecting the medial two thirds of the left proximal tibial physis in 8-10-week-old Japanese white rabbits. Autogenous chondrocytes, which had been harvested from cartilage of the knee joints, embedded in atelocollagen gel, and cultured for a week, were transplanted into the defect in the growth plate. In two other experimental groups, we transplanted autogenous fat tissue into the same defects, or left them empty. Histological and radiographic examinations were done before and after transplantation at various times up to 52 weeks postoperatively. The histological study showed that grafted chondrocytes synthesized extracellular matrix and prevented early ossification and closure of the growth plate, which occurred in the Fat and Defect groups. Angular deformity and length discrepancy in the transplanted group were less than in the control group. Our findings suggest that transplantation of autogenous chondrocytes, cultured in atelocollagen gel, may improve treatment of the injured growth plate.

Adipose Tissue↗
PubMed2002

Effect of glycosaminoglycan production on hardness of cultured cartilage fabricated by the collagen-gel embedding method.

To assess applicability of the tactile sensor in hardness measurement of cultured cartilage and to clarify the relationship between hardness and tissue structure of cultured cartilage fabricated by the collagen-gel embedding method, we studied the effect of glycosaminoglycans on hardness of such cultured cartilage using a tactile sensor and electron probe x-ray microanalyzer (EPMA). Hardness measured by the tactile sensor, that is, change in frequency of naturally oscillating piezoelectric elements caused by contact with a testing material, increased with the number of days of culture or seeding cell density. Analysis of the sulfur component in EPMA results mainly reflected glycosaminoglycans produced by chondrocytes. Sulfur mapping indicated that tissue of the cultured cartilage differed between its surface and the inside; layers rich in glycosaminoglycans and cells had formed in the surface. Changes in frequency showed close correlation with the amount of glycosaminoglycans in the surface and the inside (r = 0.98 and 0.85, respectively) of cultured cartilage measured by EPMA. Thus, the tactile sensor is capable of measuring hardness of cultured cartilage, reflecting the change in tissue structure between the surface and the inside of the cartilage.

Animals↗
PubMed2002

Symptomatic os subfibulare caused by accessory ossification: a case report.

Separated ossicles at the tip of the lateral malleolus, the condition known as os subfibulare, are sometimes a cause of ankle pain. There are two theories regarding the origin of os subfibulare. One theory proposes that it is caused by an avulsion fracture attributable to pull of the anterior talofibular ligament, whereas the other theory proposes that it is the result of an accessory ossification center. However, some authors have reported that os subfibulare is an avulsion fracture and few reports of accessory ossification have been described recently. A patient with os subfibulare that may have been caused by accessory ossification rather than an avulsion fracture was treated by the current authors.

Adolescent↗
PubMed2002

Muscle derived, cell based ex vivo gene therapy for treatment of full thickness articular cartilage defects.

OBJECTIVE: To evaluate the effectiveness of transplanted allogeneic muscle derived cells (MDC) embedded in collagen gels for the treatment of full thickness articular cartilage defects, to compare the results to those from chondrocyte transplantation, and to evaluate the feasibility of MDC based ex vivo gene therapy for cartilage repair. METHODS: Rabbit MDC and chondrocytes were transduced with a retrovirus encoding for the beta-galactosidase gene (LacZ). The cells were embedded in type I collagen gels, and the cell proliferation and transgene expression were investigated in vitro. In vivo, collagen gels containing transduced cells were grafted to the experimental full thickness osteochondral defects. The repaired tissues were evaluated histologically and histochemically, and collagen typing of the tissue was performed. RESULTS: The MDC and chondrocyte cell numbers at 4 weeks of culture were 305 +/- 25% and 199 +/- 25% of the initial cell number, respectively. The initial percentages of LacZ positive cells in the MDC and chondrocyte groups were 95.4 +/- 1.9% and 93.4 +/- 3.4%, and after 4 weeks of culture they were 84.2 +/- 3.9% and 76.9 +/- 4.3%, respectively. In vivo, although grafted cells were found in the defects only up to 4 weeks after transplantation, the repaired tissues in the MDC and chondrocyte groups were similarly better histologically than control groups. Repaired tissues in the MDC group were mainly composed of type II collagen, as in the chondrocyte group. CONCLUSION: Allogeneic MDC could be used for full thickness articular cartilage repair as both a gene delivery vehicle and a cell source for tissue repair.

Analysis of Variance↗
PubMed2002

[Autologous chondrocytes transplantation].

Hunter's observation in 1743 that cartilage "once destroyed, is not repaired" has not essentially changed for two and a half centuries. At present, there is no well-established procedure for the repair of cartilage defect with articular cartilage. Transplantation of human autologous chondrocytes in suspension, as reported by Brittberg et al., provided a potential procedure for articular cartilage repair. We have improved their procedure and developed a new technique, which creates new cartilage-like tissue by cultivating autologous chondrocytes embedded in atelocollagen gel for 3 weeks before transplantation. Good clinical results suggest that this technique should be a promising procedure for repairing articular cartilage defect.

English Abstract↗
PubMedDate not supplied

Spontaneous oscillation and mechanically induced calcium waves in chondrocytes.

The characteristics of spontaneous calcium (Ca(2+)) oscillation and mechanically induced Ca(2+) waves in articular chondrocytes were studied. In some, but not all, chondrocytes in sliced cartilage and primary cultures, we observed spontaneous oscillation of intracellular Ca(2+) that never spread to adjacent cells. In contrast, a mechanical stimulus to a single cell by touching with a glass rod induced an increase of intracellular Ca(2+) that spread to neighboring cells in a wave-like manner, even though there was no physical contact between the cells. This indicated the release of some paracrine factor from the mechanically stimulated cells. Application of ultrasonic vibration also induced an oscillation of intracellular Ca(2+). The application of a uridine 5'-triphosphate (UTP), UTP, induced a transient increase in intracellular Ca(2+) and the release of adenosine 5'-triphosphate (ATP) in cultured chondrocytes. A P2 receptor antagonist (suramin) and blockers of Cl(-) channels, niflumic acid and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), reduced the UTP-induced ATP release. The results indicated that Cl(-) channels were involved in the extracellular release of ATP following mechanical or P2Y receptor stimulation. Thus, ATP stimulation of P2Y receptors elicits an increase in intracellular Ca(2+), triggering further release of ATP from adjacent cells, thereby expanding the Ca(2+) wave in chondrocytes.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMedDate not supplied

Radius lengthening for the treatment of Bayne and Klug type II and type III radial longitudinal deficiency.

PURPOSE: We performed radius lengthening to treat radial deviation of the wrist in patients with Bayne and Klug type II and type III radial longitudinal deficiencies. The purpose of this investigation was to review our results of radius lengthening for radial longitudinal deficiency. METHODS: Beginning in 1991 radius lengthening was performed to treat 4 patients with radial longitudinal deficiency whose mean age at the initial lengthening was 16 months. The corrections for radial deviation of the wrists were performed simultaneously by soft-tissue distraction of the wrist. According to Bayne and Klug's classification 2 patients had type II and 2 patients had type III deficiencies. All but 1 patient had lengthening several times to correct the recurring discrepancy between the radius and the ulna. RESULTS: The corrections were achieved just after the lengthening but deformities recurred because of growth discrepancies between the radius and the ulna as the children grew. The radius was lengthened by a mean of 28 mm, with a mean length gain of 79%. The mean period in the fixator was 136 days. Two patients had both functionally and cosmetically acceptable correction after several lengthening procedures. In the other patient we abandoned this treatment method because of severe bone absorption at the distal end of the lengthened radius. One patient died of cardiac disease after one lengthening. CONCLUSIONS: Radius lengthening for Bayne and Klug type II and type III deficiencies may be accomplished successfully with the primary benefit of maintaining wrist and forearm motion. It is likely that at least 3 lengthenings may be required and this may need to be accompanied by a soft-tissue distraction at the ulnar carpal joint as well. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.

Child, Preschool↗
PubMedDate not supplied

Changes of the mineralization pattern in the subchondral bone plate of the glenoid cavity in the shoulder joints of the throwing athletes.

The distribution of mineralization in the subchondral bone plate (DMSB) is used as a parameter for individual stress distribution of shoulder joints. We have analyzed 28 shoulder joints of throwing athletes by DMSB of the glenoid with computed tomography osteoabsorptiometry and described their mineralization patterns. The throwing motion imposes a heavy rotational load on the shoulder joint, and this, in turn, may lead to excessive translation of the humeral head on the glenoid. This could explain why the two most frequent density maxima were localized to the anterior and posterior portions of the glenoid. Our finding of a frequent bicentric density distribution of the shoulder joints of throwing athletes should be useful in any future analysis of the relationship between the DMSB and the bone morphology of the glenoid.

Adolescent↗
PubMedDate not supplied

A new surgical technique for treating bilateral Freiberg disease.

Freiberg disease is relatively rare and difficult to treat satisfactorily. We describe a new surgical technique of osteochondral plug transplantation for late-stage Freiberg disease that may restore normal function to the metatarsophalangeal joint. In the present series, we performed osteochondral plug transplantation to treat a stage IV lesion, according to Smillie's classification, by harvesting an osteochondral plug from the non-weight-bearing site on the upper lateral femoral condyle of the ipsilateral knee. We also treated a stage II lesion using retrograde drilling. One year after surgery, the patient had no pain when running and returned to full athletic activity. The clinical and morphologic results were excellent. Arthroscopic intervention produced good results in the early stages and osteochondral plug transplantation may be an excellent surgical procedure to restore normal function to the metatarsophalangeal joint in the later stages of Freiberg disease.

Adolescent↗
PubMedDate not supplied

Results of rasping of meniscal tears with and without anterior cruciate ligament injury as evaluated by second-look arthroscopy.

PURPOSE: Meniscal rasping without suturing has been experimentally shown to stimulate vascular induction in tears in the avascular zone of menisci, resulting in meniscal healing. The goals of this study were to arthroscopically assess the results of meniscal rasping and analyze the factors affecting meniscal healing. TYPE OF STUDY: Retrospective cohort study. METHODS: Forty-eight torn menisci in 47 patients (age range, 14-47 years; average, 24 years) treated arthroscopically with the meniscal rasping technique were evaluated by second-look arthroscopy. The interval between the injury and the time of surgery ranged from 3 weeks to 13 years. There were 35 lateral and 13 medial meniscal tears associated with 44 anterior cruciate ligament injuries; 28 of the menisci had a full-thickness longitudinal tear and the other 20 had a partial-thickness tear. The length of the tears ranged from 10 to 33 mm (mean, 14.4 mm). The distance from the capsule to the tear ranged from 1 to 9 mm (mean, 5.0 mm). RESULTS: Thirty-four menisci (71%) healed completely (without a marked visible unhealed area), 10 (21%) healed incompletely, and 4 (8%) showed no evidence of healing. There were no relationships between outcome and age, gender, injured side, or time from injury and rasping. Both the distance from the capsule to the tear and the length of the tear were longer in the unhealed menisci. Stable tears had a high healing rate after meniscal rasping. CONCLUSIONS: Meniscal rasping without suturing is an easy procedure to perform and seems to be a reliable way to repair longitudinal tears in the avascular region of the meniscus, although the healing potential of the procedure is affected by the distance from the capsule to the tear site and the length and the stability of the tear.

Adolescent↗
PubMedDate not supplied

Arthroscopic drilling for chondral, subchondral, and combined chondral-subchondral lesions of the talar dome.

PURPOSE: We investigated the efficacy of drilling as a treatment for chondral (C), subchondral (S), and combined chondral-subchondral (CS) lesions of the talar dome associated with trauma, using magnetic resonance imaging (MRI), ankle arthroscopy, and the ankle-hindfoot scale of the American Orthopaedic Foot and Ankle Society (AOFAS score). TYPE OF STUDY: Case series study. METHODS: Arthroscopic drilling was performed on 72 patients whose lesions were less than 7 mm in diameter. The patients included 45 men and boys and 27 women and girls whose age at the time of surgery was between 14 and 57 years (mean age, 30.7 +/- 9.5 years). They were followed up for 24 to 71 months (mean follow-up, 39 +/- 6.4 months). RESULTS: There were 13 cases of chondral lesions, 10 cases of S lesions, and 49 cases of CS lesions. The MRI findings revealed that in the chondral lesion group, 13 cases were unchanged and 0 deteriorated; in the S lesion group, 2 improved, 8 were unchanged, and 0 deteriorated; and in the CS lesion group, 13 improved, 36 were unchanged, and 0 deteriorated. The arthroscopic findings showed that in the chondral lesion group, 2 improved, 9 were unchanged, and 1 deteriorated; in the S lesion group, all 8 cases deteriorated; and in the CS lesion group, 28 improved, 22 were unchanged, and 0 deteriorated. Drilling did not always improve the MRI and arthroscopic findings of the 3 respective types of lesions. However, the mean AOFAS score at the most recent follow-up was excellent; 91.7 +/- 2.4 points in the chondral lesion group, 93.1 +/- 2.1 points in the S lesion group, and 98.8 +/- 1.2 points in the CS lesion group. CONCLUSIONS: Our study shows that drilling did not always improve the MRI and arthroscopic findings. However, the clinical results obtained as measured by the AOFAS score were excellent.

Adolescent↗
PubMedDate not supplied

Expression of neuropeptides and cytokines at the extensor carpi radialis brevis muscle origin.

To reveal whether neuropeptides and cytokines affect the pathogenesis of tennis elbow, expressions of substance P, calcitonin gene-related peptide, interleukin 1 alpha, and transforming growth factor beta1 at the origin of the extensor carpi radialis brevis muscle were investigated in patients with tennis elbow (n = 10). Innervation in the origin was determined with use of the protein gene product 9.5. Substance P-like immunoreactivity and calcitonin gene-related peptide-like immunoreactivity were observed in the nerve fibers around small vessels without apparent infiltration of inflammatory cells. Cells showing positive interleukin 1 alpha or transforming growth factor beta1 immunoreactivity were noted in small vessels and the dense collagen meshwork in 5 of 10 cases. The results suggested that these neuropeptides and cytokines might promote inflammation and stimulate proliferation and matrix synthesis of fibroblasts, contributing to the pathology of tennis elbow.

Adult↗
PubMedDate not supplied

Role of the periosteal flap in chondrocyte transplantation: an experimental study in rabbits.

To determine the role of the periosteal flap in chondrocyte transplantation for the treatment of articular cartilage defects, a cartilage defect was created on the patellar groove of the rabbit knee. The defect was filled with chondrocytes cultured in collagen gel, and was covered with a periosteal flap the cambial layer of which was facing the patella (P group), or facing down against the bone marrow (M group). The same defect was covered with a periosteal flap that was frozen and thawed three times (F group), and an artificial collagen film (C group). At 3 and 6 months, the defects were filled with reparative tissues that showed a smooth surface and resembled hyaline cartilage in the P, M, and F groups. There were no significant differences between the reparative tissues in the three groups histologically, immunohistochemically, biochemically, and biomechanically, although the collagen film fell down into the defect and the reparative tissue had a fibrous tissue-like appearance. These results showed that the periosteal flap does not have a beneficial humoral or cellular effect on the formation of reparative tissue, suggesting that the periosteal flap might act as a mechanical barrier to prevent leakage of grafted chondrocytes.

Animals↗
PubMedDate not supplied

Allogeneic bone marrow-derived mesenchymal stromal cells promote the regeneration of injured skeletal muscle without differentiation into myofibers.

Half-stratum laceration was performed on the tibialis anterior muscle of Sprague-Dawley (SD) rats as a skeletal muscle injury model. Bone marrow-derived mesenchymal stromal cells (BMMSCs), which were derived from enhanced green fluorescent protein (GFP) transgenic SD rats, were transplanted into the injured site. Tensile strength produced by nerve stimulation was measured for functional evaluation before sacrifice. Specimens of the tibialis anterior muscles were stained with hematoxylin and eosin, and immunohistochemically stained for histological evaluation. Our results showed that transplanted BMMSCs promoted maturation of myofibers histologically and made the injured muscle acquire almost normal muscle power functionally by 1 month after transplantation. However, the results of immunohistochemical staining could not prove that transplanted BMMSCs differentiated into or fused to skeletal myofibers, although it showed that transplanted BMMSCs seemed to differentiate into muscle precursor cells. Therefore, our results indicated that BMMSCs contributed to the regeneration of skeletal muscle by mechanisms other than fusion to myofibers after differentiation.

Animals↗
PubMedDate not supplied

Three-dimensional CT imaging of flexor tendon ruptures in the hand and wrist.

OBJECTIVE: The purpose of this study is to determine the applicability of 3D CT imaging in the evaluation of flexor tendon rupture in the hand and wrist. DESIGN: Twenty-four digits in 22 patients (18 adults, 4 children) with a spectrum of finger flexion disturbances were investigated by a multidetector-row CT scanner, and diagnosed by 3D CT image with the volume rendering technique. The accuracy of the image diagnosis was confirmed operatively in 20 digits. RESULTS: 3D CT imaging gave a precise analysis in all adult cases. It clearly depicted the location of rupture and tendon stump. All of the 12 digits diagnosed from the images as tendon rupture were operated on, and the operational finding correlated well with the diagnosis based on the image. In the children, the image analysis was equivocal. CONCLUSIONS: 3D CT imaging can be useful when the diagnosis of flexor tendon rupture cannot be made based on trauma history and clinical examinations, and can be helpful in surgical planning.

Adolescent↗
PubMedDate not supplied

Arteriovenous malformation of the ring finger. Pre- and postoperative evaluation using three-dimensional computed tomography angiography.

We experienced a case of arteriovenous malformation of the ring finger. The lesion was examined by three-dimensional computed tomography angiography with volume rendering and maximum intensity projection techniques pre- and postoperatively. The images demonstrated the location and extent of the lesion and were quite useful for surgical planning and the evaluation of operative results. Three-dimensional computed tomography angiography may be a valuable diagnostic tool even in the evaluation of peripheral vascular lesions.

Adult↗
PubMedDate not supplied

Evaluation of anterior talofibular ligament lesion using 3-dimensional computed tomography.

OBJECTIVE: The aim of this study was to evaluate the applicability of 3-dimensional computed tomography (3D CT) imaging for the diagnosis of anterior talofibular ligament (ATFL) injury. METHODS: Six patients with lateral instability of ankle joint were examined with 3D CT preoperatively. Three patients had chronic ATFL tear, and the others had os subfibulare. 3D CT images were compared with magnetic resonance imaging and the operative findings. RESULTS: The ATFL in the uninvolved side could be depicted clearly by 3D CT in all patients. In patients with chronic ATFL tear, 3D CT could evaluate the condition of ATFL remnant much better than MRI. In patients with os subfibulare, the relationship between bone fragment and ATFL was clearly imaged in 3D CT. Surgical findings in all patients were correlated well with 3D CT. CONCLUSIONS: This study showed that 3D CT has the possibility of being a useful diagnostic tool for evaluation of ATFL lesion.

Adolescent↗