Search PubMed⌕ Search

Biomedical subjects

M Ochi

Publications and source records attributed to M Ochi.

At least 73 records · Page 4Linked to original sources
PubMed2000

Coronary bypass surgery using the internal thoracic artery after reconstruction of occluded subclavian artery.

We present two cases with an occluded left subclavian artery requiring coronary artery bypass grafting. A preoperative angiogram confirmed that the subclavian artery, including the internal thoracic artery distal from the occlusion, was thoroughly intact, in both cases. Immediately after reconstructing the subclavian artery using an aortoaxillary bypass with an 8 mm ring-reinforced polytetrafluoroethylene graft, each patient underwent double coronary artery bypass grafting using the affected left internal thoracic artery with either the right internal thoracic artery or a saphenous vein in the same anesthetic setting. Symptomatic relief was excellent. In both cases, a postoperative angiographic study showed good function of the left internal thoracic artery graft supplying blood to the coronary artery through the aortoaxillary bypass graft.

Aged↗
PubMed2000

Repair of articular cartilage defects with cultured chondrocytes in Atelocollagen gel. Comparison with cultured chondrocytes in suspension.

We attempted to repair full-thickness articular cartilage defects in rabbit knee joints with allogeneic cultured chondrocytes embedded in Atelocollagen gel. An articular cartilage defect was created on the patellar groove of the femur. The defect was filled with chondrocytes cultured in the collagen gel and covered with periosteal flap (G group). In three other experimental groups, the same defects were transplanted with chondrocytes in monolayer culture with periosteal flap (M group), periosteal graft only (P group), or left empty (E group). At 4, 12, and 24 weeks after operation, the reparative tissue was analyzed macroscopically and histologically. At 4 weeks after operation, the surfaces of the reparative tissue were smooth, and the defects were filled with reparative tissues that resembled hyaline cartilage in all four groups. However, the reparative tissues degenerated gradually with time in the M, P, and E groups. In contrast, in the G group, the reparative tissue retained its thickness, and there was a steady integration of the grafted tissue into the adjacent normal cartilage at 24 weeks after operation. The results suggest that transplantation of allogeneic chondrocytes cultured in Atelocollagen gel is effective in repairing an articular cartilage defect.

Animals↗
PubMed2000

Influence of trypsin on the biological bonding of cartilaginous surface to bone in rabbits.

Biological healing between cartilage and bone is difficult, because their histological structure and physiological function are completely different, and the healing ability of cartilage is limited. A full-thickness articular cartilage defect was created in the femoral groove of 48 Japanese white rabbits. The defects were filled with a piece of articular cartilage from the contralateral patella with its superficial zone facing down to the defect. Before grafting, a piece of articular cartilage was treated with 0.05% trypsin or phosphate-buffered saline (PBS) for 5 min. The healing process was histologically observed at 2, 4, 8, and 16 weeks after operation. We found that the incorporation process of cartilage implant treated with trypsin was much better than that of PBS-pretreated cartilage. Proliferation and reorganization of chondrocytes in the cartilage implant and subchondral bone ingrowth were observed in the trypsin-pretreated group. Although the observation period in our study was not very long, our results suggest that trypsin pretreatment might be one of the most promising methods to facilitate the repair process between cartilage and bone.

Analysis of Variance↗
PubMed2000

Anterior cruciate ligament augmentation under arthroscopy. A minimum 2-year follow-up in 40 patients.

We present a new surgical technique of anterior cruciate ligament (ACL) augmentation using autogenous hamstring tendons or allogenic fascia lata under arthroscopy for patients in whom considerable ACL remnants with mechanoreceptors are preserved. We review the clinical results of 40 patients who underwent this ACL augmentation, as assessed by manual instability tests, KT-2000 knee arthrometer, Lysholm and Gillquist score, joint position sense and magnetic resonance imaging (MRI), and compare them with those of ACL reconstruction. The side-to-side differences of anterior displacement measured by the KT-2000 knee arthrometer at 30 lbs, an average of 5.3 +/- 2.6 mm preoperatively, was significantly improved to an average of 0.7 +/- 1.8 mm in the augmentation group, while an average of 6.0 +/- 2.4 mm was improved to 1.8 +/- 2.1 mm in the reconstruction group. There was no statistically significant difference between the preoperative values in the two groups, but the postoperative values of the augmentation group were significantly less than those of the reconstruction group. The ratio of anterior terminal stiffness of the augmentation group was 1.2 +/- 1.8, and that of the ACL reconstruction group was 0.7 +/- 0.4. This was a statistically significant difference (P < 0.05). Thus, as for the KT-2000 knee arthrometer, the ACL augmentation group showed significantly better anteroposterior stability and terminal stiffness than the ACL reconstruction group. The final inaccuracy of joint position sense of the augmentation group was 0.7 degrees +/- 0.7 degrees, while that of the reconstruction group was 1.7 degrees +/- 1.2 degrees indicating a significant difference (P < 0.05). This study demonstrates that ACL augmentation, which can preserve ACL remnants with mechanoreceptors, is superior to ACL reconstruction from the viewpoint of position sense and joint stability.

Adolescent↗
PubMed2000

Evaluation of core decompression for early osteonecrosis of the femoral head.

Twenty-six hips (19 patients) with osteonecrosis of the femoral head with stage I or II of the disease, according to the Ficat and Arlet classification, underwent core decompression. Osteonecrosis was confirmed histologically in all 26 hips. Of 19 patients, 7 had prognostic factors traditionally associated with poor outcome including collagen vascular disease and continued use of steroids. The follow-up period averaged 7 years 10 months (range: 2 years 5 months-13 years 8 months) for 17 patients with 24 hips. Two patients died secondary to systemic illness. Seventeen hips (65.4%) had very good or good results using the Ficat criteria. Eight hips (30.8%) needed further operation [total hip arthroplasty (THA) for 7 hips, osteotomy for 1 hip]. Of the 12 hips in patients who had used steroids, 6 hips (50%) were converted to THA. Four hips in patients with systemic lupus erythematosus (SLE) needed THA (100%). We conclude that core decompression provides an effective treatment for steroid-associated osteonecrosis other than in cases with SLE, as well as providing effective treatment for non-steroid-associated osteonecrosis in the early stages of the disease.

Adult↗
PubMed2000

Systemic administration of adenosine A(2A) receptor antagonist reverses increased GABA release in the globus pallidus of unilateral 6-hydroxydopamine-lesioned rats: a microdialysis study.

The ability of adenosine A(2A) receptor antagonists to exhibit antiparkinsonian activity has recently been reported, but the mechanisms of action are still unknown. Since A(2A) receptors have been localized to GABAergic striatopallidal neurons, it is probable that these antagonists affect the activity of these neurons. In the present study, extracellular GABA basal levels were increased in the ipsilateral striatum and globus pallidus following a unilateral 6-hydroxydopamine lesion of the nigrostriatal pathway. The A(2A) receptor-selective antagonist KW-6002 (3mg/kg, p.o.) caused a marked and sustained decrease of extracellular GABA levels in the globus pallidus of the 6-hydroxydopamine-lesioned rats, whereas no changes in GABA levels were observed in the globus pallidus of the non-lesioned rats. Microinjection of the A(2A) receptor agonist CGS21680 (0.005-0.5 microg) into the striatum of non-lesioned animals increased GABA concentrations in the globus pallidus, which was abolished by the voltage-dependent Na(+) channel blocker tetrodotoxin (1 micromol/l) delivered locally to the globus pallidus via the dialysis membrane. Furthermore, intrapallidal infusion of CGS21680 (10 micromol/l) also increased GABA levels in the globus pallidus. These data indicate that GABA release from striatopallidal neurons is regulated through A(2A) receptors in both the striatum and globus pallidus. The reversal of the 6-hydroxydopamine-induced increase in pallidal GABA levels by KW-6002 suggests that the antiparkinsonian effects of A(2A) receptor antagonists occur on the striatopallidal neurons.

Adenosine↗
PubMed2000

Pretibial cyst formation after anterior cruciate ligament reconstruction using auto hamstring grafts: two case reports in a prospective study of 89 cases.

Eighty-nine cases after anterior cruciate ligaments (ACL) reconstruction were followed prospectively with magnetic resonance imaging (MRI). The patients were examined using axial and sagittal MRI at least twice during the postoperative evaluation of reconstructed ACL. Two cases of pretibial cyst formation were observed. At the time of cyst formation, neither patient had any subjective or objective evidence of knee instability. The cyst of one case communicated with the intra-articular. The minimum follow-up period after the surgical excision was 9 months, with no evidence of recurrence. We might speculate that the critical period for cyst formation in both patients occurred at less than 12 months after their ACL reconstruction. We concluded that the cyst formation was most likely due to incomplete graft tendon incorporation within the osseous tunnel.

Adolescent↗
PubMed2000

Cloning and embryonic expression patterns of the zebrafish Runt domain genes, runxa and runxb.

We isolated zebrafish homologues of the Runt-related transcription factor gene family (Runx family), runxa and runxb, and analyzed their developmental expression patterns. The deduced amino acid sequence of Runxa was highly homologous to that of AML1 (also called CBFA2, PEBP2alphaB or Runx1), a critical regulator of mammalian hematopoiesis expressed in cells of the hematopoietic lineage as well as other tissues. During zebrafish development, the runxa gene was not expressed in hematopoietic tissues but in the olfactory placodes and cells attached to the otic vesicles. We identified three kinds of runxb transcripts, which encoded two types of proteins with different N-terminal regions. The Runxb proteins were highly similar to AML2 (CBFA3, PEBP2alphaC or Runx3). The expression sites of the shared region of runxb mRNAs during development were the trigeminal ganglions, dorsal neurons of the neural tube and the lateral line primordia. These findings show that expression patterns of the zebrafish Runx genes are distinct from that of the mammalian genes.

Animals↗
PubMed2000

Impact of sequential grafting of the internal thoracic or right gastroepiploic arteries on multiple coronary revascularization.

OBJECTIVE: The aim of the study is to clarify the efficacy of the sequential anastomotic technique of the arterial conduits for multiple coronary revascularization. BACKGROUND: The internal thoracic artery (ITA) is now widely accepted as a durable conduit for myocardial revascularization. The right gastroepiploic artery (GEA) has been developed as a third in situ arterial graft with an outcome similar to that of the ITA. MATERIAL AND METHOD: One hundred and forty five consecutive patients (116 male, 29 female, mean age 60.4yr) who received sequential grafting of either the ITA or GEA or both were retrospectively analysed. RESULTS: Sequential anastomoses were performed in 121 in situ left ITAs, 36 in situ GEAs and 12 composite right ITAs. No in situ right ITA was anastomosed sequentially. Two to six vessels (mean 3.8) were revascularized for each patient. Of the total 543 bypassed vessels, 432 (79.6%) were reconstructed with the arterial grafts. In 85 patients with quadruple bypass or more, the arterial grafts were able to reconstruct 266 out of 360 (74.0%) target vessels. Seventy one patients (49.0%) were revascularized without venous grafts. The arterial grafts could revascularize 293 out of 310 vessels (94.5%) in the LAD approximately Diagonal region, 83 out of 113 (73.4%) in the distal RCA or Cx region. There were no cardiac events responsible for the arterial grafts in the follow up period. CONCLUSION: In light of our experience, multiple revascularization with in situ arterial sequential grafts is feasible. Aggressive application of this technique provides patients requiring multiple coronary revascularization with favorable long-term results.

Abdomen↗
PubMed2000

Quantitative cell and matrix changes in human humeral head osteoarthritic cartilage.

A new quantitative method was devised both to establish an objective standard for morphometric diagnosis and to determine the extent of degeneration in osteoarthritic cartilage. Eight normal and forty-eight osteoarthritic humeral heads, subsequently confirmed by light microscopy, were obtained at necropsy. The articular cartilage was observed in situ with a laser scanning confocal microscope (LSCM) and morphometric measurements determined cell density (cells/mm), cell volume fraction (%) and mean cell volume (microm3). The osteoarthritic cartilages were classified according to the following four characteristics: increase in thickness, increase in cell volume fraction, decrease in cell volume fraction, and fibrous pannus. Deviations in cell density and cell volume fraction from normal means were calculated as extent of degeneration. Our present approach aims to provide valuable clues, such as objective stereological information and a unique reference for biochemical and traditional morphological analyses, that clinicians will be able to use in combination with other methods in order to establish a reliable diagnosis.

Aged↗
PubMed2000

Pulsed electromagnetic fields promote bone formation around dental implants inserted into the femur of rabbits.

The present study examined the effect of applying a pulsed electromagnetic field (PEMF) on bone formation around a rough-surfaced dental implant. A dental implant was inserted into the femur of Japanese white rabbits bilaterally. A PEMF with a pulse width of 25 microseconds and a pulse frequency of 100 Hz was applied. PEMF stimulation was applied for 4 h or 8 h per day, at a magnetic intensity of 0.2 mT, 0.3 mT or 0.8 mT. The animals were sacrificed 1, 2 or 4 weeks after implantation. After staining the resin sections with 2% basic fuchsin and 0.1% methylene blue, newly formed bone around the implant on tissue sections was evaluated by computer image analysis. The bone contact ratios of the PEMF-treated femurs were significantly larger than those of the control groups. Both the bone contact ratio and bone area ratio of the 0.2 mT- and 0.3 mT-treated femurs were significantly larger than the respective value of the 0.8 mT-treated femurs (P < 0.001). No significant difference in bone contact ratio or bone area ratio was observed whether PEMF was applied for 4 h/day or 8 h/day. Although a significantly greater amount of bone had formed around the implant of the 2-week treated femurs than the 1-week treated femurs, no significant difference was observed between the 2-week and 4-week treated femurs. These results suggest that PEMF stimulation may be useful for promoting bone formation around rough-surfaced dental implants. It is important to select the proper magnetic intensity, duration per day, and length of treatment.

Alloys↗
PubMed2000

Adverse effects of saline neurolysis on a chronically compressed rat sciatic nerve.

We have evaluated the effect of saline neurolysis compared with a simple decompression procedure on chronically compressed sciatic nerves in rats. Eight months after the initiation of nerve compression within a silicone tube, rats were divided into three groups of 35. In group I, saline was injected subepineurially at the compressed segment of the nerve after removal of the tube (decompression plus saline neurolysis). The nerves in group II were treated by removal of the tube only (simple decompression). In group III the tubes were left in place. Adding saline neurolysis to decompression provided no histological, morphometric, electrophysiological, or vascular advantages up to four months, and even gave worse results than simple decompression. We conclude that saline neurolysis has no beneficial effect on a chronically compressed nerve and it is not recommended for clinical use.

Animals↗
PubMed2000

Proprioceptive improvement in knees with anterior cruciate ligament reconstruction.

The correlation between the prospective course of proprioceptive improvement and knee stability after anterior cruciate ligament reconstruction was investigated in 38 patients. Proprioception, on the basis of the patient's capacity to reposition the limb accurately, was evaluated at 3-month intervals for 24 months after hamstring graft anterior cruciate ligament surgery. Knee stability was evaluated concurrently with a KT-2000 knee arthrometer. Thirty patients experienced improvement in postoperative position sense in at least one of the examinations, although eight patients had no improvement at any time. Of the 30 patients who had improvement, 28 maintained improved position sense from 18 months to the final followup. Thirty patients maintained significantly better knee stability for a postoperative period of at least 24 months. These results indicated that a minimum of 18 months after anterior cruciate ligament reconstruction may be needed for complete restoration of the proprioceptive function in knees, although the mean position sense in all patients gradually improved from 9 months. Improvement in postoperative knee stability may have facilitated recovery of proprioception.

Adolescent↗
PubMed2000

Role of off-pump coronary artery bypass grafting in patients with malignant neoplastic disease.

Although the long-term benefits of conventional coronary artery bypass grafting (CABG) are obvious, postoperative morbidity and mortality and the length of recovery associated with cardiopulmonary bypass are the main concerns of cardiac surgeons and cardiologists. The aim of this study was to demonstrate the effectiveness and advantage of the off-pump CABG for patients with concomitant malignant disorders requiring myocardial revascularization. From March 1997 to February 1999, 51 patients underwent off-pump CABG. Of these, there were 9 patients who had concomitant malignant disease requiring noncardiac surgery: gastric cancer (4), urinary bladder cancer (2), cholangioma (1), lung cancer (1) and colon cancer (1). Off-pump CABG was performed through a sternotomy, left thoracotomy or subxiphoid incision. Five patients received single grafting and 4 received double. The mean operative time for the off-pump CABG was 167 min. The total amount of bleeding during the off-pump CABG was 450-890 ml. Simultaneous noncardiac operations were carried out in 5 patients. The other 4 patients underwent subsequent operations for the malignancy uneventfully. In contrast, of the 4 patients with concomitant malignant disorders who underwent standard CABG during the period before the use of off-pump CABG, 2 died without undergoing the subsequent noncardiac operation. Off-pump CABG is quite efficient and is of great advantage in patients with malignancy who require myocardial revascularization in addition to noncardiac surgery for the cancer.

Aged↗
PubMed2000

Effectiveness of an insole with a lateral wedge for idiopathic osteonecrosis of the knee.

For the purpose of investigating the effect of an insole with a lateral wedge, we studied 30 patients (31 knees) aged from 46 to 78 years with idiopathic osteonecrosis of the knee for at least three years. The 18 knees treated with an insole (group I) were matched by age, gender, obesity index, area of lesion, femorotibial angle, stage, and clinical evaluation with 13 treated conservatively without an insole (group II). The clinical results, as rated by a knee score, improved significantly more in group I than in group II. Radiologically, the necrotic area and ratio decreased in group I, whereas in group II they increased. In advanced cases, with stage 4 or a femorotibial angle of more than 180 degrees, the use of an insole did not improve the clinical or radiological findings. The insole is a valuable method of conservative treatment for the early stages of osteonecrosis of the medial femoral condyle.

Aged↗
PubMed2000

Effectiveness of prostaglandin E1 on pulmonary hypertension and right cardiac function induced by single-lung ventilation and hypoventilation.

It is known that prostaglandin E1 (PGE1) is a potent vasodilator and improves red cell deformability. Single lung-ventilation sometimes occurs under lung transplantation, lung cancer surgery and traumatic pneumonectomy, and may result in increased pulmonary resistance, right heart failure and severe hypoxemia. The present experimental study was undertaken to examine the effects of PGE1 on these states induced by single-lung ventilation and hypoventilation. Fourteen pigs weighing 32-33 kg were anesthetized, intubated and ventilated using a respirator and then randomly assigned to two groups, the control group and the PGE1 treated group, 7 pigs each. After median sternotomy to induce severe hypoxemia hypoventilation was induced and then the right hilus pulmonis was cross clamped. Mean blood pressure, mean pulmonary arterial pressure (PAP), pulmonary vessel resistance (PVR), right ventricular stroke work (RVSW) and arterial blood gases (PaO2 and SatO2) were measured at baseline, in the hypoventilation state, and 15 min, 1 hour, and 2 hours after the right hilus pulmonis clamping with hypoventilation. PGE1 (250 microg/20 ml saline) was administered via the central vein starting 15 min after right hilus cross clamping for 1 hour and 45 min in the PGE1 group. PGE1 significantly reduced PAP and PVR, normalized RVSW, and improved PaO2. PGE1 may be useful for the condition of increased pulmonary hypertension during single-lung ventilation and hypoventilation.

Alprostadil↗
PubMed2000

[Clinical usefulness of cross-linked N-telopeptide of type I collagen (NTx) as a bone metastatic marker in patients with prostate cancer--comparison with serum PICP, PINP and ICTP].

Type I collagen cross-linked N-telopeptide (NTx) in urine, the degraded form of type I collagen cross-linked in bone, has been evaluated as a marker of bone resorption. In this study, the clinical usefulness of NTx as a marker of bone metastasis of prostate cancer was compared with that the carboxyterminal propeptide of type I procollagen (PICP), the aminoterminal propeptide of type I procollagen (PINP), and the pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) in serum. We assessed 37 cases of prostatic cancer in which the diagnosis had been confirmed pathologically. The patients were 15 patients with prostatic cancer with bone metastasis (before treatment or during a relapse) (Group 1); 11 patients, with bone metastasis, but for whom treatment was effective and condition had stabilized (Group 2); and 11 patients, with localized prostatic cancer and no evidence of bone metastasis (Group 3). The serum PICP, PINP, and ICTP levels and concentration of NTx in urine were compared among the three groups with the Mann-Whitney U test, with p values less than 0.05 considered significant. Urine NTx concentrations in Groups 1, 2 and 3 were 539.3 +/- 202.9, 160.6 +/- 97.6 and 48.6 +/- 7.6 nMBCE/mMCr, respectively. The differences between the Group 1 and Group 2 and between Group 1 and Group 3 were significant (p < 0.01 and p < 0.001). The differences between Group 1 and Group 3 and between Group 2 and Group 3 were significant for serum PICP, PINP and ICTP concentrations (p < 0.05). The correlation coefficient between urine NTx and each serum bone metabolic marker was 0.8 for PICP, 0.4 for PINP and 0.5 for ICTP. These bone metabolic markers are promising clinical markers of bone metastatic and may be useful for prediction of therapeutic efficacy and recurrence in bone and quantification of the extent of bone metastates.

Biomarkers, Tumor↗