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Biomedical subjects

K Takaoka

Publications and source records attributed to K Takaoka.

At least 19 recordsLinked to original sources
PubMed1992

Bone mineral density in the proximal femur and hip fracture type in the elderly.

Bone mineral density (BMD) in the contralateral proximal femur in 100 female elderly patients with hip fracture and the 35 controls without hip fracture were investigated using dual-photon absorptiometry. The hip fracture patients were divided into intracapsular fracture (n = 53) and extracapsular fracture (n = 47) groups, and these two groups were further divided into five subgroups according to fracture site: intracapsular fracture type 1 (transcervical fracture, n = 29) and type 2 (subcapital fracture, n = 24); extracapsular fracture type 1 (intertrochanteric line fracture, n = 13), type 2 (pertrochanteric fracture, n = 28), and type 3 (combined type of pertrochanteric and subtrochanteric fracture, n = 6). The intracapsular fracture group showed BMD values similar to those of controls; the extracapsular fracture group showed significantly lower BMD values than controls. When these two were subclassified into five subgroups, different results were seen in terms of BMD value in the proximal femur and fracture types; intracapsular fracture type 1 showed BMD values equivalent to those of controls; on the other hand, type 2 showed significantly lower BMD value than controls, and the BMD distribution in the proximal femur among the extracapsular fracture subgroups 1-3 differed, although all of them showed significantly lower BMD values than controls. The degree of trauma causing the fractures was also assessed according to available anamnestic data, but no significant difference was found in trauma tendency between the intra- and the extracapsular fracture group or among the subgroups in each group.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1992

Immunohistochemical, autoradiographic and electron microscopic studies on the transformation of fibroblasts into chondrocytes in the mouse subfascia induced by bone morphogenetic protein.

Functional morphology on the transformation of fibroblasts into chondrocytes induced by bone morphogenetic protein (BMP) was studied by light and electron microscopy using 35S autoradiography and immunohistochemistry for S-100 protein and type-II collagen. A pellet containing BMP obtained from a murine osteosarcoma was transplanted into the mouse subfascia. By 3 days after implantation, many typical fibroblasts, which were free of the silver grains for 35S and devoid of both S-100 protein and type-II collagen, entered the pellet region. By 5 days, the fibroblasts in the pellet region became polygonal in shape, and cytoplasmic vesicles and vacuoles appeared, both containing a homogeneous substance of low electron density. At 5 days, autoradiography revealed many silver grains for 35S over the Golgi apparatus and vesicles and vacuoles of the cells in the pellet region as well as over the surrounding extracellular matrix. Moreover, the cells at 5 days displayed immunoreactivity to both proteins. The extracellular matrix around the cell began to show clear metachromasia and increased in amount with time. At 9 days all the cells in the pellet region were round or oval in shape and surrounded by an abundant cartilaginous matrix. The rough endoplasmic reticulum and Golgi apparatus were extremely well developed, and a large number of vacuoles and vesicles were seen in the cytoplasm. These cells showed intense immunoreactivity to both proteins, and strong accumulation of sulfur was visualized in the extracellular matrix by autoradiography. These results suggest that the fibroblasts in the pellet region change into chondroblasts by 5 days, and become typical chondrocytes by 9 days.

Animals↗
PubMed1992

Immunolocalization of alkaline phosphatase in osteoblasts and matrix vesicles of human fetal bone.

A monoclonal antibody raised against alkaline phosphatase (ALP) of human osteosarcoma was used to localize this enzyme in human fetal bone tissue. For light microscopy, the presence of alkaline phosphatase in osteoblasts and osteocytes was demonstrated by use of an avidin-biotin immunoperoxidase procedure. Electron microscopic immunolocalization was accomplished with an indirect immunoperoxidase method which revealed a concentration of the enzyme on matrix vesicle and osteoblast plasma membranes. In addition, many vesicular protrusions arising from areas of plasma membrane on the lateral surfaces of adjacent osteoblasts were strongly immunolabeled. Immunostaining for ALP was absent in vesicles which contained fine crystallites. Alkaline-phosphatase-rich matrix vesicles may play a significant role in the mineralization of the extracellular matrix.

Alkaline Phosphatase↗
PubMed1992

Ossification of the ligamentum flavum induced by bone morphogenetic protein. An experimental study in mice.

Ossification of the ligamentum flavum and secondary spinal-cord compression were produced experimentally in mice by implanting bone morphogenetic protein (BMP) in the lumbar extradural space. The ligamentum flavum became hypertrophied and ossified, and protruded into the spinal canal. The thickness of the ossified ligament increased gradually with time, leading to compression and deformation of the spinal cord which showed various degrees of degeneration. Demyelination occurred in the posterior and lateral white columns and neuronal loss or chromatolysis in the grey matter. The pathological findings in the experimental animals closely resemble those found in the human disease and suggest that BMP may be a causative factor of ossification of the ligamentum flavum in man. This experimental model may be useful for the study of myelopathy caused by gradual spinal-cord compression.

Animals↗
PubMed1992

Rotational osteotomy for non-traumatic avascular necrosis of the femoral head.

We reviewed 41 hips in 40 patients at three to 11 years (average 6.3 years) after Sugioka transtrochanteric rotational osteotomy for non-traumatic avascular necrosis of the femoral head. The clinical results were excellent or good in 23 hips (56%) and the radiological success rate was 56%. Failure was due to fracture of the femoral neck, nonunion of the osteotomy, secondary collapse, or osteoarthritis. Nonunion and femoral neck fracture were more common after the use of the large screws described by Sugioka than with AO blade plates. Secondary collapse was significantly more common when less than one-third of the posterior articular surface was intact (p = 0.002). Postoperative degenerative changes were seen in cases with stage III avascular necrosis. We conclude that success depends to a large extent on the amount and stage of necrosis of the femoral head, but that careful technique and the use of AO hip plates may increase the likelihood of a satisfactory result.

Adult↗
PubMed1992

[Three cases of chronic respiratory tract lesions associated with adult T-cell leukemia (ATL)].

Three cases of chronic respiratory tract lesions as a complication of adult T-cell leukemia (ATL) are reported. Case 1 was seropositive for HTLV-1 on recent examination following treatment of bronchiolitis. Chest radiograph revealed over inflation of the lungs and bilateral diffuse small nodular shadows. Pulmonary function test resulted hypoxemia and mixed ventilation disorder. Pathological examination confirmed lymphocytic infiltration of the bronchiolar wall. Both clinically and pathologically the patient was diagnosed as having diffuse panbronchiolitis (DPB). Therefore, this case was considered to be the bronchiolar type of HTLV-1 associated bronchiolo-alveolar disorder (HABA). The other two cases with smoldering or chronic ATL presented with long-standing symptoms of productive cough due to chronic respiratory lesions. We consider that all three cases had HTLV-1 virus associated pulmonary lesions, but with different clinical and pathological presentations. Among 12 cases of bronchiolitis experienced at our hospital, three were positive for HTLV-1.

Adult↗
PubMed1992

Efficacy of alumina ceramic heads for cemented total hip arthroplasty.

Fifty-seven cemented total hip arthroplasties (THAs) were reviewed in cases of osteoarthrosis secondary to congenital dysplasia or dislocation. The bearing surface of the prosthesis used in this series consists of a polyethylene acetabular component on an alumina ceramic head. All acetabular components were positioned at the same level as the original acetabulum, and an autologous femoral head graft was performed for 18 hips. The follow-up period ranged from five to eight years, averaging six years two months. The latest survey showed excellent and good results for 53 hips (92.9%). Four acetabular components (7%) and two femoral components (3.5%) showed roentgenographic evidence of loosening. Only one hip (1.8%) had to be treated with revision surgery for femoral component loosening. None of the cases suffered a broken ceramic head. The use of a total hip prosthesis with an alumina ceramic head in THA is likely to lead to excellent results for patients with osteoarthrosis of the hip.

Adult↗
PubMed1992

[A case of renal cell carcinoma with lung metastasis and local recurrence effectively treated with nephrectomy and UFT].

A 74-year-old woman was admitted on July 18, 1989 for an abnormality on her chest roentgenogram. Right renal tumor with bilateral pulmonary metastasis was detected and right nephrectomy was performed. Because of the progression of pulmonary metastasis and the local recurrence after surgery, UFT was orally administered at a dose of 300 mg everyday since Dec. 12, 1989. The chest roentgenogram on Nov. 21, 1990 showed progression of lung lesions. But at the 20 th month after the beginning of chemotherapy, both lung lesions disappeared completely and local recurrence around the operative wound strikingly improved. This is a rare case of renal cell carcinoma with local recurrence and lung metastasis successfully treated with UFT.

Administration, Oral↗
PubMed1992

Bipolar prosthetic replacement for the treatment of avascular necrosis of the femoral head.

Eighty-three hips in 66 patients with nontraumatic avascular necrosis of the femoral head (ANFH) showing evidence of severe collapse or secondary osteoarthritic changes were treated with surgical implantation of bipolar hip prostheses either with or without cement fixation of femoral stems. The cases were observed for more than three years (range, three to ten years seven months; average, five years seven months) and assessed in terms of functional and roentgenographic results. These data were compared with the results of classic hemiarthroplasties using fixed head prostheses (Austin-Moore-type with curved or straight stem) that were performed at the authors' institutions before 1980. The results confirm that the clinical outcome is improved with use of the bipolar prosthesis. Satisfactory results (a score of 80 or greater on a hip function scoring system proposed by the Japanese Orthopaedic Association) were maintained throughout the follow-up period in most cases (71 of 83 hips) with the bipolar prosthetic replacements. In a group of patients with unsatisfactory results (12 hips), proximal migration of prosthetic head was seen in two cases. The incidence of proximal migration of bipolar heads, including those exhibiting minimal movement, was significantly lower when compared with that observed in an Austin-Moore-type head-fixed prosthesis group (7/83 versus 12/19) during a comparable postoperative follow-up period. It is noteworthy that the proximal migration of the bipolar head was not progressive, and, in most cases observed more than five years, the cartilaginous spaces of acetabulum were preserved, whereas in the Austin-Moore-replaced group, the migration was evident and progression occurred within three years of surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Experimental steroid-induced osteonecrosis in adult rabbits with hypersensitivity vasculitis.

Osteonecrosis (ON) was experimentally induced in rabbits by employing a combined protocol of hypersensitivity vasculitis and administration of high-dose corticosteroids. Thirty-five adult rabbits were used: five were injected twice with horse serum (Group A), five were injected three times with methylprednisolone acetate (Group B), 20 were treated with a combination of horse serum and methylprednisolone acetate (Group C), and five were used as a control (Group D). Both femurs of each rabbit were obtained one to five weeks after the final treatment and were histologically examined. There was no evidence of ON in Groups A, B, and D, whereas vasculitis was prominent in the femurs of Group A rabbits. In Group C, 14 of 20 specimens (70%) showed histologic evidence of ON in the femoral metaphysis: seven showed marrow necrosis and seven marrow and trabecular necrosis. Intramedullary hemorrhage was detected in eight animals. All specimens that showed ON or marrow necrosis revealed arteriopathy (i.e., severe damage to the vascular wall structure of arterioles). These findings were similar to those observed in early ON of clinical materials. The authors conclude that arteriopathy plays an important role in the pathogenesis of ON.

Animals↗
PubMed1992

The fate of nontraumatic avascular necrosis of the femoral head. A radiologic classification to formulate prognosis.

One hundred fifteen hips in 87 patients with non-traumatic avascular necrosis of the femoral head (ANFH) (men, 54; women, 33) (steroid induced, 49; alcoholic, 21; idiopathic, 17) were radiologically classified into six distinct types (Types 1A, 1B, 1C, 2, 3A, and 3B) based on the following: (1) the size and location of the necrotic area in relation to the weight-bearing surface of the acetabulum as seen on anteroposterior views in the standing position and (2) initial roentgenographic abnormalities. The natural course of the disorder in each group were observed for more than two years (range, two to 18 years; mean, five years). Of the 79 hips without collapse of the femoral heads (Stage II) at the beginning of follow-up evaluation, 42 femoral heads subsequently collapsed. These collapses took place predominantly in cases involving Types 1C, 2, and 3B. Conversely, the incidence of collapse was significantly low in the other groups (Types 1A, 1B, and 3A). Collapse of the femoral head occurred in 78 femoral heads of 115. The incidences of collapse by group was 0% for Type 1A, 19% for Type 1B, 94% for Type 1C, 100% for Type 2, 12% for Type 3A, and 100% for Type 3B. These data indicate that this radiologic classification of necrosed femoral heads is useful for evaluation of the risk of collapse or for prognosis of the affected hip joints as well as for choosing an appropriate treatment modality, either conservative or surgical, during the early stages of ANFH.

Female↗
PubMed1992

Intraosseous arterial architecture in nontraumatic avascular necrosis of the femoral head. Microangiographic and histologic study.

To determine the vascular architecture of nontraumatic avascular necrosis of the femoral head (ANFH), 38 femoral heads procured from 31 ANFH patients were studied by microangiographic and histologic methods. Microangiography showed that the head was consistently stratified into three zones: the normal vascular, the reparative vascular, and the avascular. Microangiographic abnormalities were closely correlated with the histologic changes in each zone. The extent of the necrotic area proved to depend on the extent and number of involved intraosseous nutrient arteries. Circumscribed necrosis accompanied interruption of the lateral epiphyseal arteries in their intra-capital portion. Extensive necrosis resulted from multiple vascular involvement, which included not only the lateral epiphyseal arteries, but also the superior and inferior metaphyseal arteries. Histologic examination of different levels of the nutrient arteries revealed many intraosseous pathologic vascular changes in apposition to the ischemic episode of the femoral head. Interruption of the blood supply causing ANFH occurs in the intracapital arteries probably because of vascular wall damage, and the extent of necrosis depends on the number of the involved nutrient arteries and their proximity to the intracapital site of origin.

Adult↗
PubMed1992

Evaluation of polylactic acid homopolymers as carriers for bone morphogenetic protein.

Polylactic acid (PLA) homopolymers with molecular weights of 105,000; 21,000; 3300; 650; and 160d (PLA105000, PLA21000, PLA3300, PLA650, and PLA160, respectively) were prepared and evaluated as carriers for bone morphogenetic protein (BMP). Composites consisting of 4 mg of water-soluble, semipurified BMP and 100 mg of one of the PLA homopolymers were implanted into the dorsal muscles of mice. PLA105000/BMP, PLA21000/BMP, PLA3300/BMP, and PLA160/BMP composites failed to induce new bone formation; PLA105000, PLA21000, and PLA3300 elicited foreign-body reactions or chronic inflammation (or both), and PLA160 produced tissue necrosis. PLA650/BMP composites induced cartilage formation within one week and induced bone with hematopoietic marrow at three weeks postimplantation. PLA650/BMP composites were completely absorbed and replaced by new bone. The results suggest that within this group of PLA homopolymers, PLA650 may be the only type suitable for use as a BMP carrier.

Animals↗
PubMed1992

[A case of Swyer-James syndrome with bilateral lesions].

A 16-year-old female was admitted for the treatment of bronchial asthma. She had a history of measles pneumonia at four years of age. Her chest radiograph revealed right unilateral hyperlucency. She was diagnosed as having Swyer-James syndrome from the results of computed tomography, pulmonary angiography, bronchoscopy, and perfusion-ventilation scintigrams, which revealed unsuspected bilateral involvement, and irregularity of severity and distribution. In addition, she had a hypoplastic right upper bronchus, pulmonary hypertension, pneumothorax, and bronchial asthma. The findings of bilateral involvement, irregular distribution, and bronchial lesions strongly suggest that the etiology in this case was damage to the airways caused by measles infection in childhood.

Adolescent↗
PubMed1991

Telopeptide-depleted bovine skin collagen as a carrier for bone morphogenetic protein.

The telopeptide of type I collagen is thought to be responsible for causing immunogenic response when introduced into xenogenic hosts. To eliminate this problem, solubilized bovine skin collagen was filtered through a millipore membrane, digested repeatedly with pepsin to remove telopeptides, and used as a carrier for a water-soluble, partially-purified fraction of bone morphogenetic protein (BMP) in mice. Composite implants of this telopeptide-depleted collagen and the partially-purified BMP fraction consistently elicited ectopic bone formation in mice 3 weeks postimplantation. When implanted alone, collagen or BMP failed to show this response. Collagens, prepared by use of conventional methods (acid-solubilized collagen, or collagen-digested once with pepsin) were also assessed as carriers for BMP, but were found to be inferior in terms of consistency of bone formation and amount of induced bone mass. The results suggest that telopeptide-depleted collagen permitted a gradual release of purified BMP for induction of bone, with minimal immunogenic interference. Consequently, this collagen carrier represents an important development for future clinical application of BMP.

Amino Acids↗
PubMed1991

Monoclonal antibody against human bone alkaline phosphatase.

A monoclonal antibody which reacts preferentially with human bone alkaline phosphatase (AP) has been developed using human osteosarcoma bone AP as an immunogen. The antibody with the highest selectivity shows about three- and a-half fold greater binding to bone than to liver AP. The selectivity was confirmed using mixtures of authentic samples of the bone and liver isoenzymes. Its selectivity was also shown by measurements of bone AP in sera from patients with either bone or liver diseases. Such a selective antibody could lead to the development of a monoclonal antibody highly specific for bone AP which can be used for a more sensitive approach for quantitative analysis of the isoenzyme.

Alkaline Phosphatase↗
PubMed1991

Preservation of ectopically induced bone in the mouse by estradiol.

The effects of estrogen on bone formation and bone resorption were examined in an experimental model of ectopic bone induction. In this experimental model, ectopic ossicles of uniform size were elicited reproducibly in three weeks by implanting pellets containing murine osteosarcoma derived bone morphogenetic protein (BMP), into the muscles of mice. Thereafter the induced ossicles showed a gradual reduction in bone mass due to negative bone balance. To estimate the effects of estrogen on bone formation and bone resorption, beta-estradiol-3-benzoate was administered exogenously to host mice from day 21 to day 41 (0.45 micrograms/g body weight, on alternate days, 10 treatments). Radiologic and histologic analysis confirmed the positive effect of estradiol on preserving bone mass over this period. Quantitative analysis showed an increase in the Ca content in ossicles after 21 days of estradiol treatment (139.1% of the baseline value on day 21). In the control group, the bone mass was reduced (47.4% of that on day 21). Bone resorption was determined by the reduction in 45Ca radioactivity from ossicles prelabeled with this radioisotope before estradiol administration. The rate of loss of the prelabeled 45Ca radioactivity was suppressed by estradiol (68.8% of prelabeled value in estradiol treated group and 87.7% in control group). The effect of exogenous estrogen on the bone forming phase of bone turnover in the ossicles was quantified by incorporation of 45Ca and 3H-proline. These bone formation parameters were increased to 2.2 and 1.9 times higher than those of the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗