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T Akisue

Publications and source records attributed to T Akisue.

17 recordsLinked to original sources
PubMed2001

Establishment and characterization of cell line TNMY1 derived from human malignant fibrous histiocytoma.

Although malignant fibrous histiocytoma (MFH) is one of the most common soft tissue sarcomas, its pathogenesis remains unclear. In this study, a cell line derived from human MFH, TNMY1, was established from a metastatic chest-wall lesion of a 60-year-old woman with MFH. The TNMY1 cell line was passaged 95 times, and it still retained the biological characteristics of the original tumor. TNMY1 consists of spindle-shaped cells and pleomorphic cells associated with multinucleated giant cells. Immunohistochemical studies showed that the spindle-shaped and pleomorphic cells were positive for vimentin, CD68 and alpha-smooth muscle actin, but negative for epithelial membrane antigen, desmin, muscle actin, alpha-sarcomeric actin, myoglobin, lysozyme and S-100 protein. The cells expressed collagen types I, III and V. These results indicate that MFH may originate from mesenchymal stem cells with the potential to differentiate into either fibroblasts or histiocytes. An elevated level of collagen type V mRNA expression is considered to support a diagnosis of MFH.

Animals↗
PubMed2001

Paratibial cyst associated with wear debris after total knee arthroplasty.

We present a case in which a synovial cyst arose from the proximal tibia and expanded in the calf of a patient after total knee arthroplasty. A cystogram showed a direct communication between the joint cavity and the cyst, apparently associated with a screw that penetrated the tibial cortex. Histologic examination of the cyst showed an inflammatory reaction, including macrophages, foreign body giant cells, and metal and polyethylene particles. To our knowledge, this is the first case report illustrating a paraosseous cyst that developed after total knee arthroplasty. Wear debris from the total knee prosthesis may have been responsible for this unusual cyst.

Arthroplasty, Replacement, Knee↗
PubMed2001

Elastofibroma in shoulder osteoarthritis: a theoretical concept of the etiology.

A case of unilateral, subscapular elastofibroma dorsi secondary to degenerative osteoarthritis in the ipsilateral glenohumeral joint is presented. A 69-year-old woman had experienced symptoms of osteoarthritis in the right shoulder since contracting septic arthritis when she was 7 years old. The patient noticed a soft tissue mass in the right subscapular region when she was 65 years old. The range of motion of the glenohumeral joint was severely restricted. Histopathologic examination of the excised mass revealed elastofibroma. The authors think the excessive scapulothoracic motion was important in formation of the lesion. This case indicates that elastofibroma is not a true neoplasm but a reactive lesion formed by repetitive minor trauma.

Aged↗
PubMed2000

Solid aneurysmal bone cyst in the humerus.

We report on a 69-year-old woman with a solid variant of aneurysmal bone cyst (solid ABC) in the left humerus with a pathological fracture. Radiographically, the lesion exhibited a relatively well-defined osteolytic lesion in the diaphysis of the left humerus. On magnetic resonance (MR) imaging, the medullary lesion exhibited a homogeneous signal intensity isointense with surrounding normal muscles on the T1-weighted images and a mixture of low and high signal intensity on the T2-weighted images. Contrast-enhanced T1-weighted images revealed diffuse enhancement of the entire lesion. The pathological study showed a proliferation of fibroblasts, histiocytes, chronic inflammatory cells and numerous multinucleated giant cells in a collagenous matrix. Abundant osteoid formation in the matrix was observed, but the cells were devoid of nuclear atypia. Aneurysmal cystic cavities were absent. A review of the English literature found 22 cases of solid ABC of the long bones.

Aged↗
PubMed2000

The spatial location of impingement in total hip arthroplasty.

Impingement between acetabular and femoral components produces wear debris and results in abnormal loads on the edge of the implant. To characterize further the spatial location of impingement and the design and alignment factors associated with impingement, we reviewed 111 retrieved acetabular components from a single manufacturer. The location of impingement in the pelvis was determined by combining the location of impingement in the retrieved implants and the spatial orientation of the acetabular components measured from available radiographs. Evidence of impingement was identified in 39% of the retrieved implants and involved the posterior portion of the acetabulum in all cases. Posterior impingement was probably the result of femoral extension and external rotation, a motion that occurs during the toe-off phase of the gait cycle. Cups with impingement were more anteverted than those without impingement (P = .016). There was a significant inverse association between impingement and the size of the femoral head, and the mean head-to-neck diameter ratio for implants with impingement was smaller than that for implants without impingement (P < .0001). Factors that appear to be associated with impingement include i) excessive cup anteversion combined with posterior positioning of the extended rim and ii) femoral components with relatively small head-to-neck diameter ratio.

Adult↗
PubMed1999

Polyethylene wear vector in vivo: a three-dimensional analysis using retrieved acetabular components and radiographs.

Polyethylene wear of the acetabular component can be described as one or more vectors. To help clarify the mechanisms of wear advancement in vivo, we used a combination of retrieved implants and radiographs to describe the three-dimensional wear vectors in total hip arthroplasty. The wear vectors in 41 retrieved implants from a single manufacturer were measured with use of the shadowgraph technique, and the spatial orientation of each implant was calculated from serial anteroposterior pelvic radiographs. On the basis of the combination of the wear vector in the implant and implant orientation in the pelvis, the wear vectors in vivo were determined. The mean wear vector was directed 8.1 degree lateral in the coronal plane and 4.1 degree posterior in the sagittal plane. The wear vectors in vivo showed a relatively wide range of directions, not necessarily coinciding with the commonly presumed resultant force in the hip. The wear vectors were not associated with the spatial orientation of the acetabular components, but cups with impingement demonstrated more anterior wear than did those without impingement. Our results suggest that the process of polyethylene wear is not as simple as previously described and that several factors influence advancement of wear in vivo.

Acetabulum↗
PubMed1999

Multidirectional deformation in fully congruent acetabular components.

Most clinical studies have used femoral head migration as an index of acetabular wear, but a previous study showed multiple wear vectors in 30% of retrieved acetabular components with noncongruent liners. The origin of multiple wear vectors is unclear, and it has been suggested that polyethylene creep in a noncongruent shell might influence deformation on the articular surface. We used shadowgraph and volumetric methods to evaluate the extent and direction of surface deformation of 37 retrieved polyethylene liners that were fully congruent to a single design of metal backing. The results show that multiple deformation vectors are relatively common in retrieved acetabular cups (27% in this study) and are independent of congruency between liner and metal backing, rim impingement, and backside creep. Polyethylene liners with multiple wear vectors were significantly thinner than those of cups with a single vector. The origin of multiple vectors is still unclear, but clinical and laboratory studies measuring linear wear alone without recognizing multiple vectors underestimate total in vivo volumetric wear.

Acetabulum↗
PubMed1998

Requirement of GM2 ganglioside activator for phospholipase D activation.

Sequence analysis of a heat-stable protein necessary for the activation of ADP ribosylation factor-dependent phospholipase D (PLD) reveals that this protein has a structure highly homologous to the previously known GM2 ganglioside activator whose deficiency results in the AB-variant of GM2 gangliosidosis. The heat-stable activator protein indeed has the capacity to enhance enzymatic conversion of GM2 to GM3 ganglioside that is catalyzed by beta-hexosaminidase A. Inversely, GM2 ganglioside activator purified separately from tissues as described earlier [Conzelmann, E. & Sandhoff, K. (1987) Methods Enzymol. 138, 792-815] stimulates ADP ribosylation factor-dependent PLD in a dose-dependent manner. At higher concentrations of ammonium sulfate, the PLD activator protein apparently substitutes for protein kinase C and phosphatidylinositol 4,5-bisphosphate, both of which are known as effective stimulators of the PLD reaction. The mechanism of action of the heat-stable PLD activator protein remains unknown.

Amino Acid Sequence↗
PubMed1998

Purification of a heat-stable activator protein for ADP-ribosylation factor-dependent phospholipase D.

A heat-stable activator for ADP-ribosylation factor (ARF)-dependent phospholipase D (PLD) was purified to near homogeneity from rat kidney cytosol by a sequential column chromatography. The purified activator has a molecular mass of 23 kDa on SDS-PAGE. Using a partially purified ARF-dependent PLD from rat kidney, the activator synergistically stimulates PLD with ARF in time- and dose-dependent manner. In the absence of ARF, the activator has little or no effect. The purified activator also stimulates PLD under several conditions including permeabilized cell system, suggesting that the activator is a physiologically relevant regulator of PLD.

ADP-Ribosylation Factors↗
PubMed1996

Reconstitution of GTP-gamma-S-dependent phospholipase D activity with ARF, RhoA, and a soluble 36-kDa protein.

For activation of kidney membrane phospholipase D (PLD), cytosol is absolutely needed in addition to GTP-gamma-S. The active component of cytosol consists of three protein factors: ADP-ribosylation factor, RhoA, and a soluble 36-kDa protein. Any combination of these two factors synergistically activates PLD to some extent, but the presence of the three factors causes full activation. The 36-kDa protein is stable at 60 degrees C but inactivated at 80 degrees C for 10 min. Tissue distribution of the 36-kDa protein roughly coincides with that of PLD, suggesting physiological relevance of the protein in the regulation of PLD.

ADP-Ribosylation Factors↗
PubMed1995

Mammalian phospholipase D: activation by ammonium sulfate and nucleotides.

Phospholipase D (PLD) associated with the rat kidney membrane was activated by guanine 5'-[gamma-thio]triphosphate and a cytosol fraction that contained ADP-ribosylation factor. When assayed by measuring the phosphatidyl transfer reaction to ethanol with exogenously added radioactive phosphatidylcholine as substrate, the PLD required a high concentration (1.6 M) of ammonium sulfate to exhibit high enzymatic activity. Other salts examined were far less effective or practically inactive, and this dramatic action of ammonium sulfate is not simply due to such high ionic strength. Addition of ATP but not of nonhydrolyzable ATP analogue adenosine 5'-[beta, gamma-imido]diphosphate further enhanced the PLD activation approximately equal to 2- to 3-fold. This enhancement by ATP needed cytosol, implying a role of protein phosphorylation. A survey of PLD activity in rat tissues revealed that, unlike in previous observations reported thus far, PLD was most abundant in membrane fractions of kidney, spleen, and liver in this order, and the enzymatic activity in brain and lung was low.

Adenosine Triphosphate↗
PubMed1995

Potential role of protein phosphorylation in GTP-gamma-S-dependent activation of phospholipase D.

Mammalian phospholipase D (PLD) is known to require nearly absolutely guanosine 5'-Q-3-thiotriphosphate (GTP-gamma-S) and a small G-protein for its activation. In streptolysin-Q-permeabilized HL-60 cells, phorbol ester or diacylglycerol enhanced greatly this PLD activation in the presence of ATP-Mg2+. Non-hydrolysable ATP analogue was inactive. This phorbol-ester-induced PLD activation was completely counteracted not only by protein kinase C (PKC) inhibitors but also by tyrosine kinase inhibitors. In cell-free lysates, the GTP-gamma-S-dependent activation of PLD was stimulated by ATP-Mg2+. This stimulation by ATP-Mg2+ did not respond to phorbol ester nor was it inhibited by PKC inhibitors, but was fully restrained by tyrosine kinase inhibitors. The results suggest that protein phosphorylation reactions by PKC and tyrosine kinase may take part, possibly in this order, in the small G-protein-coupled PLD activation.

Adenosine Triphosphate↗
PubMedDate not supplied

Ossified intramuscular hemangioma: multimodality imaging findings.

Whereas calcification of hemangiomas is common, ossification is unusual. Multimodality imaging findings of a rare case of an ossified intramuscular hemangioma in the calf of a 24-year-old woman are presented. Radiographic, computed tomographic, magnetic resonance (MR), scintigraphic, and histologic features of this case are reported. The radiologic differential diagnosis of an ossified mass in soft tissue is also discussed.

Adult↗
PubMedDate not supplied

Intraosseous lipoma of the humeral head: MR appearance.

Intraosseous lipoma is the rarest benign primary bone tumor. We report a case of juxtaarticular intraosseous lipoma in the humeral head of a 50-year-old man. Roentgenographic, computed tomographic (CT), magnetic resonance (MR), scintigraphic, and histologic findings of this case are presented.

Biopsy, Needle↗