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J Aoki

Publications and source records attributed to J Aoki.

At least 163 records · Page 9Linked to original sources
PubMed1991

[MR evaluation of wallerian degeneration of the pyramidal tract].

This study is based on 135 magnetic resonance (MR) exams of 110 patients with wallerian degeneration of the pyramidal tract shown on MR images acquired on a mid field imaging scanner. The MR findings of wallerian degeneration were abnormal signal band along the course of the pyramidal tract and ipsilateral brain stem shrinkage. In all 110 cases an abnormal signal band was seen on T2-weighted spin-echo images, that is, a hypointense band in four exams between 30 days and 116 days after onset of symptoms, and hyperintense bands in 122 exams. The hyperintense signal on T2-weighted images was shown in most cases after 200 days from the onset. In one case a signal of the pyramidal tract showed a hyperintense band at 7 days, hypointense at 30 days, and hyperintense again at 123 days after onset. Sequential MR exams of another case showed gradual narrowing of the hyperintense signal band and progression of the ipsilateral brainstem shrinkage. The narrowing of the pyramidal tract and the ipsilateral brain stem shrinkage tended to be shown after 6 months from onset.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Neural cell adhesion molecule mediates contact-dependent inhibition of growth of near-diploid mouse fibroblast cell line m5S/1M.

A near-diploid mouse fibroblast cell line m5S/1M used in this study shows a high sensitivity to contact-dependent inhibition of growth, and the addition of EGF causes both morphological change and loss of contact-dependent inhibition of growth. The m5S/1M cell and its transformants obtained by x-ray irradiation have been used to search for the cell surface glycoproteins that are responsible for the growth regulation via cell-cell interactions. Lectin blotting analyses showed that the expression of the cell surface glycoprotein of 140 kD (140KGP) is highly sensitive to the transformation induced either by x-ray irradiation or by the EGF stimulation. We purified the 140KGP and found that it was composed of two glycoproteins. The major component of 140KGP was identified as neural cell adhesion molecule (NCAM) by amino acid sequence analyses of the peptide fragments and by the cross-reactivity with anti-NCAM mAb, clone H28.1.2.3. Monoclonal antibody against 140KGP (clone LN-10) recognizes all three isoforms of NCAM expressed on m5S/1M cell and showed that the expression of NCAM was highly sensitive to the transformation. Furthermore, the immobilized LN-10 strongly inhibited the growth of actively proliferating m5S/1M cells and the LN-10 in a soluble form showed a significant growth-stimulating effect on the confluent quiescent cultures of m5S/1M cells. The results show that NCAM plays a major role in the contact-dependent inhibition of growth of m5S/1M, and that NCAM might be involved in the regulation of cell growth during embryogenesis and formation of nervous systems.

Amino Acid Sequence↗
PubMed1991

Development of a high-resolution digital tomosynthesis system and its clinical application.

Conventional tomography has been criticized for its low contrast caused by scattered radiation and tomographic blur. The authors developed a digital tomosynthesis system as a substitute for conventional tomography. With the image processor in the system, two types of postprocessing can be performed to improve the quality of synthesized tomograms. One-dimensional spatial frequency filtering effectively reduces linear tomographic blur and enhances image information when an appropriate filter is used. Correction of structure mottle helps enhance the image clarity. The system allows reconstruction of tomograms at any desired depth and performance of tomosynthetic angiography and dual-energy subtraction. The system solves some of the problems associated with plain tomography and dual-energy subtraction and provides diagnostic clinical images.

Humans↗
PubMed1991

Sugar-specific inhibitory effects of wheat germ agglutinin and phytohemagglutinin-E4 on histamine release induced by basic secretagogues from rat peritoneal mast cells and their possible action sites.

The histamine release induced by compound 48/80, bradykinin or polyethylenimine with a molecular weight of 600 (PEI6) was inhibited by wheat germ agglutinin (WGA) and phytohemagglutinin E-subunits (PHA-E4), and the inhibition was specifically reversed by N-acetyl glucosamine and N-acetyl galactosamine, respectively. Concanavalin A (Con A) and phytohemagglutinin L-subunits (PHA-L4) did not inhibit the histamine release induced by compound 48/80, bradykinin or PEI6. The histamine release induced by substance P was also inhibited sugar-specifically by WGA and PHA-E4. The binding sites for compound 48/80, bradykinin, PEI6 and substance P, therefore, seemed to especially overlap each other. These binding sites were found to be glycoproteins having affinities to WGA and PHA-E4, but not to Con A and PHA-L4. The binding of WGA and PHA-E4 to the glycoproteins resulted in inhibition of the interaction between the basic secretagogues including bradykinin and substance P and their binding sites on the mast cells. The bindings of five lectins to mast cell glycoproteins were examined by lectin-blotting. Several glycoproteins, which had specific affinities to WGA and PHA-E4, but not to Con A and PHA-L4 were detected. We assumed that the binding sites for basic secretagogues which are coupled with histamine-releasing mechanisms exist among these glycoproteins. A 41-kDa protein (alpha-subunit of pertussis toxin-sensitive G protein) was not detected by WGA, suggesting that the binding sites for the basic secretagogues were not G proteins.

Acetylgalactosamine↗
PubMed1991

[Clinicopathological study of nephropathy in patients with rheumatoid arthritis].

We carried out a retrospective study to investigate the clinical and pathological findings in 31 patients with rheumatoid arthritis (RA). In clinical findings, 17 patients showed nephrotic syndrome, five had isolated proteinuria, two had proteinuria and hematuria and seven had renal failure. In pathological findings, there were 16 patients with membranous nephropathy (MN), two with proliferative glomerulonephritis (DPGN), two with minor glomerular abnormality (MGA), six with amyloidosis, 2 with tubulointerstitial nephritis, and three patients had accompanying lupus nephritis. Eleven of 16 with MGN had been treated with gold, bucillamine or D-penicillamine, so they were diagnosed as drug induced MGN. In the other five patients, we could not decide which drugs induced the nephropathy. The 2 cases of MGA were associated with nephrotic syndrome and acute renal failure, which were caused by non-steroidal antiinflammatory drugs. There were two cases of non-Ig A DPGN, which was regarded as the native nephropathy in RA. The three cases with lupus nephritis were diagnosed as systemic lupus erythematosus by the criteria of the American Rheumatism Association (ARA). In conclusion, the nephropathy in patients with RA was varied and renal biopsy was a useful examination.

Adult↗
PubMed1991

Abscessed leiomyosarcoma of the ileum.

A-49-year-old man was admitted because of a lower abdominal mass. During the five days prior to admission, he had noted fever and lower abdominal pain. Palpation of the abdomen revealed a tender mass, 10 cm in diameter, in the suprapubic region. An x-ray revealed an irregular collection of gas, 9 cm in diameter, in the pelvic cavity, which appeared as a mirror image when the patient was upright. Based on the physical finding and the results of a barium enema, abdominal CT, MRI, and small intestine imaging, a diagnosis of leiomyosarcoma of the ileum was made. Excision of the tumor and part of the small intestine was performed. A saccular tumor, 11 x 6 x 5 cm, was found 1.0 m from the cecum and growing out of the wall of the ileum. A large amount of pus was found inside the cavity. The pathological diagnosis was leiomyosarcoma.

Abscess↗
PubMed1991

[A study on the appropriate fixation for the procedures for the better preservation of cellular antigenicity and morphology of the blood smear in immunocytochemistry: an improvement of the immunostain technique using alkaline-phosphatase (ALP) as a labeling enzyme].

The authors previously reported a new coloration method which utilized hexazotized newfuchsin as a coupler for the immuno-enzyme-cytochemistry. This procedure used alkaline-phosphatase (ALP) as the labeling enzyme. The insolubility of the reaction product to organic solvents made it possible to prepare permanent slides. However, this suffered from several drawbacks, due to the fixation procedures, in the preservation of better morphology and antigenicity of the cell. The present study was undertaken to overcome such problems by modifying the fixation procedure. The study utilized twenty monoclonal and polyclonal antibodies commonly used in immunohematological staining. Various fixative solutions and timing of fixation were evaluated. The results indicated that; 1) the best fixative solution was a mixture of buffered paraformaldehyde (PFA) and acetone (10 ml 40% PFA solution, 10 ml pH 6.6 0.02 M phosphate buffer, 20 ml distilled water, 60 ml acetone, with pH adjusted to 6.6-7.4 with HCl) and 2) the fixation should be performed just before the immunostain. The results further showed that unstained smear slides, when freshly air dried and stored in a desicator, could maintain various differentiation antigens (CD2, 3, 4, 5, 8, 10, 14, 15, 16, 19, 25, L26, HLA-DR) for at least 4 weeks without any change in the immuno-reactivity. Thus, we conclude that this improved fixation procedure is an optimum fixative and should be used in routine application of the immunostain method for blood smears.

Alkaline Phosphatase↗
PubMed1990

Osteoid osteoma of the elbow. A review of six cases.

Six cases of osteoid osteoma of the elbow were reviewed to determine the spectrum of clinical, pathologic and radiologic findings. Since osteoid osteoma of the elbow may masquerade as a nonspecific synovitis, the diagnosis is challenging and frequently delayed. The histology is, however, indistinguishable from that of osteoid osteoma occurring in typical locations. The radiologic features of osteoid osteoma of the elbow include the following triad: (a) osteosclerosis, usually a dominant feature at initial imaging and typically enveloping the nidus; (b) joint effusion; and (c) periosteal reaction that can involve both the bone in which the osteoid osteoma arises and adjacent bones. Awareness of these features will facilitate correct diagnosis, thereby facilitating timely and appropriate treatment.

Adult↗
PubMed1990

Osteoblastoma of the spine. A review of 75 cases.

Clinical and radiologic features of 75 cases of osteoblastoma of the spine were reviewed. In addition to pain, which was the most frequent complaint, 18 patients demonstrated objective neurologic deficit, while scoliosis was observed in 17 patients. Aspirin yielded pain relief in 13 patients. Pathologic fracture was not encountered. The radiologic and histologic characteristics of osteoblastoma of the spine are indistinguishable from those arising in other sites. The typical lesion exhibited a well-defined, geographic margin with a sclerotic, frequently lobulated border. Approximately one half of the cases were predominantly lucent, the remainder displaying varying degrees of matrix mineralization. Distribution of the osteoblastomas through the spinal axis was as follows: cervical-29, thoracic-16, lumbar-17, sacral-13. Other significant findings included posterior element involvement in 73 of 75 cases, and a striking male to female ratio of 2.5 to 1.

Adult↗
PubMed1990

[Effect of maternally derived antibody levels on antibody responses to canine parvovirus, canine distemper virus and infectious canine hepatitis virus after vaccinations in beagle puppies].

Antibody titers against canine parvovirus (CPV), canine distemper virus (CDV) and infectious canine hepatitis virus (ICHV) in serum were measured in 6 beagle dams and their 38 puppies bred in our colony, in order to clarify the effects of maternally derived antibodies to antibody responses against the viruses after vaccinations in puppies. Correlation coefficient on antibody titers between puppies and dams were CPV: r = 0. 7935, CDV: r = 0.8194 and ICHV: r = 0.8105. Mean maternal antibody positive rates in 7-day-old puppies from their dams were CPV: 67%, CDV: 46% and ICHV: 45%. Mean half-lives of the maternal antibodies in puppies were estimated to be CPV: 13.5 days, CDV: 15.1 days and ICHV: 15.4 days. The antibody response against CPV vaccination in puppies was mainly observed in dogs being titers of less 1:5 and positivity was 39% (15/38 puppies) after 1st vaccination at 42 days after birth, and 82% (31/38 puppies) after 2nd vaccination at 70 days. That against CDV vaccination (at 56 days after birth) was seen highly in dogs being titers of less 1:10 and positivity was 53% (20/38). Also that against ICHV vaccination (at 56 days after birth) was seen frequently in dogs being titers of less 20 holds and the rate was 87% (33/38). From these results, it was estimated that the age when high antibody response against each vaccination could be expected in puppies might be CPV: between 40 and 69 days, CDV: between 32 and 92 days and ICHV: between 31 and 52 days, respectively.

Age Factors↗
PubMed1990

HLA epitopes detected by serology.

There is evidence that many of the so-called multispecific cytotoxic antisera react to the amino acid-defined epitopes of the HLA-A and B loci molecules. This evidence is based on the finding that a group of sera produced allelic reactions which corresponded to amino acid substitutions. Antisera for 29 amino acid variants were identified at 67 variable residues on the A locus and for 17 of the 51 variable sites on the B locus. The results were validated by showing that the reactions produced by testing cells from 111 individuals on an epitope typing tray fit the Hardy Weinberg equilibrium. This means that the alleles defined by the antisera behaved as alleles in the random population. Tests of homozygous cells on the epitope typing trays produced completely mutually exclusive reaction patterns as expected on the basis of the amino acid substitutions. Two examples are cited in which immunization across a single HLA "antigen" difference existed between donor and recipient, resulting in a "multispecific" antiserum. The specificities contained in the serum exactly fit an amino acid difference between the donor and recipient.

Alleles↗
PubMed1990

HLA class II epitope detection by serology.

The amino acid sequence for the Class II specificities on 70 homozygous cell lines was compared with the cytotoxic reactions produced by 13,000 allogenic antisera against these lines. Many of the cytotoxic reaction patterns correlated completely with unique amino acids at a given residue. Therefore, we inferred that the antibodies were reacting directly with these amino acid-defined residues. Among 131 variable DRB1 residues, several well-correlated antisera were found to 64 (49%). Among 94 DQB1 residues, antibodies were found to 59 (63%). The location of these serologically defined epitopes on the molecule is shown in the table. We conclude that much of the serologic reactions of Class II can be explained by reactivity to the amino acid-defined epitopes. It can be shown that many of the sera that were previously considered multispecific are directed against these epitopes. These serologically defined epitopes are clearly immunogenic and are probably important in transplant matching.

Amino Acid Sequence↗
PubMed1990

Nodular glomerulosclerosis in a patient showing impaired glucose tolerance.

We report a case showing typical diabetic nodular glomerulosclerosis without retinopathy or other apparent clinical findings of DM except for impaired glucose tolerance. The 57-year-old man had a family history but no personal history of DM. In an extensive examination for DM, the results of funduscopy, daily profile of serum glucose and hemoglobin Alc were entirely within normal limits. However, the oral glucose tolerance test was abnormal. A renal biopsy showed typical nodular lesions (Kimmelstiel-Wilson's lesions). Previously, the interesting feature of transient proteinuria had been recognized. Although hypocellular nodular lesions by light microscopy are characteristic of diabetic nephropathy, renal amyloidosis, carbon disulfide intoxication, multiple myeloma and light chain disease, we concluded that the present lesions had resulted from diabetic nephropathy based on the family history, patient history, impaired glucose tolerance, immunofluorescent findings and electron microscopic observations.

Diabetic Nephropathies↗
PubMed1989

Primary tumors of the patella. A review of 42 cases.

This study reports 42 cases of histologically proven and radiographically correlated primary patellar tumors. Despite diverse histologic diagnoses, the radiographic appearances of benign as opposed to malignant patellar neoplasms are essentially indistinguishable. Although the literature suggests that giant cell tumor is the most frequent benign tumor of the patella, the most common benign neoplasm in this series is chondroblastoma (16 cases). Only four primary malignant lesions were encountered, three cases of lymphoma and one case of hemangioendothelioma. Since 38 (90%) of the 42 cases were benign, a benign etiology should be strongly favored, notwithstanding the radiographic appearance, whenever a primary patellar tumor is encountered.

Adolescent↗
PubMed1989

Giant cell tumor of the scapula. A review of 13 cases.

This study reviews the demographic, radiologic, and histologic characteristics of 13 cases of an important primary skeletal neoplasm, giant cell tumor of bone, occurring in an uncommon location, the scapula. That eight of 13 patients presented prior to 20 years of age contrasts significantly with the typical age distribution (between 20-40 years) encountered in giant cell tumors arising in long bones. As it does elsewhere in the skeleton, giant cell tumor of the scapula frequently demonstrates cystic and/or telangiectatic components on histologic examination. The radiologic appearances of giant cell tumor in the scapula and in more typical locations are similar and include: (1) well-defined (geographic) margins, occasionally with a delicate sclerotic rim, (2) prominent trabeculations, (3) "expanded" bone contour, (4) frequent extension to the subchondral plate, and (5) absence of internal mineralization. Tumor sites within the scapula included: coracoid process, acromion, and body (three cases each); glenoid (two cases); and superior and inferior angles (one case each).

Adolescent↗