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Biomedical subjects

M Tomonaga

Publications and source records attributed to M Tomonaga.

At least 235 records · Page 13Linked to original sources
PubMed1994

[Abscess formation in a Rathke's cleft cyst].

A 66-year-old woman with a diagnosis of asymptomatic Rathke's cleft cyst had been observed for almost 2 years and was admitted to our hospital in June 1992 because of high fever and loss of consciousness. Ophthalmological examination revealed right Horner's sign and ophthalmoplegia. A tentative diagnosis of bacterial meningitis was made based on the results of a lumbar puncture. T1-weight MRI showed a marked increase in the size of the suprasellar cystic mass lesion compared to the MRI images obtained 2 years earlier. Hence, the preoperative diagnosis was pituitary abscess. Both transsphenoidal and nasal drainage of the abscess were performed. The pathological findings were consistent with a Rathke's cleft cyst and showed chronic inflammatory cells. The postoperative course was uneventful and the patients eye movements recovered completely. The possible mechanisms of abscess formation in Rathke's cleft cyst are discussed.

Aged↗
PubMed1994

Maffucci's syndrome associated with intracranial chordoma: case report.

This report discusses Maffucci's syndrome associated with intracranial chordoma. Of the 170 reported cases of this syndrome, only 27 have been associated with intracranial lesions and none was involved with intracranial chordoma. Chordomas are occasionally difficult to differentiate from chondroma and chondrosarcoma. An immunohistochemical analysis was able to prove, however, that the chordoma of this case significantly differed from chondroma and chondrosarcoma.

Biomarkers, Tumor↗
PubMed1994

[Co-operative study of all-trans retinoic acid as a differentiation induction therapy of acute promyelocytic leukemia].

Efficacy and safety of tretinoin (all-trans retinoic acid, ATRA, Ro01-5488) for refractory and relapsed acute promyelocytic leukemia were studied by multi-institutional study in Japan. 22 out of 27 (81.5%) patients with previously untreated who were intolerable to chemotherapy, relapsed and refractory were achieved CR. And 4 out of 11 (36.4%) in relapsed patients who received ATRA remission induction therapy previously responded. Side effects, such as dryness of the lip and skin, headache, increase of triglyceride, beta-lipoprotein and lactate dehydrogenase, were observed in 36 of 41 eligible patients (87.8%) but these were well tolerated. In addition to these, hyperleukocytosis in 4 cases and retinoic acid syndrome in 3 cases were observed. However, all patients were prescribed tretinoin again by adequate management.

Administration, Oral↗
PubMed1994

Cancer incidence in atomic bomb survivors. Part III. Leukemia, lymphoma and multiple myeloma, 1950-1987.

This paper presents an analysis of data on the incidence of leukemia, lymphoma and myeloma in the Life Span Study cohort of atomic bomb survivors during the period from late 1950 through the end of 1987 (93,696 survivors accounting for 2,778,000 person-years). These analyses add 9 additional years of follow-up for leukemia and 12 for myeloma to that in the last comprehensive reports on these diseases. This is the first analysis of the lymphoma incidence data in the cohort. Using both the Leukemia Registry and the Hiroshima and Nagasaki tumor registries, a total of 290 leukemia, 229 lymphoma and 73 myeloma cases were identified. The primary analyses were restricted to first primary tumors diagnosed among residents of the cities or surrounding areas with Dosimetry System 1986 dose estimates between 0 and 4 Gy kerma (231 leukemias, 208 lymphomas and 62 myelomas). Analyses focused on time-dependent models for the excess absolute risk. Separate analyses were carried out for acute lymphocytic leukemia (ALL), acute myelogenous leukemia (AML), chronic myelocytic leukemia (CML) and adult T-cell leukemia (ATL). There were few cases of chronic lymphocytic leukemia in this population. There was strong evidence of radiation-induced risks for all subtypes except ATL, and there were significant subtype differences with respect to the effects of age at exposure and sex and in the temporal pattern of risk. The AML dose-response function was nonlinear, whereas there was no evidence against linearity for the other subtypes. When averaged over the follow-up period, the excess absolute risk (EAR) estimates (in cases per 10(4) PY Sv) for the leukemia subtypes were 0.6, 1.1 and 0.9 for ALL, AML and CML, respectively. The corresponding estimated average excess relative risks at 1 Sv are 9.1, 3.3 and 6.2 respectively. There was some evidence of an increased risk of lymphoma in males (EAR = 0.6 cases per 10(4) PY Sv) but no evidence of any excess in females. There was no evidence of an excess risk for multiple myeloma in our standard analyses.

Adolescent↗
PubMed1994

[Allogeneic bone marrow transplantation for two patients with acute myeloid leukemia with trilineage myelodysplasia (T-MDS)].

Case 1: A 26-year-old female was admitted because of leukocytosis with 43.6% myeloblasts and 33.6% monocytes, and trilineage myelodysplasia (T-MDS) was detected on bone marrow (BM) smear. She was diagnosed as having acute myeloid leukemia (AML) (M4) with T-MDS and was treated with the Japan Adult Leukemia Study Group (JALSG) AML87 protocol. After completion of chemotherapy, leukemic myeloblasts remained minimally and myelodysplastic changes were still detected on BM smear. She underwent allo-BMT from an HLA-identical sibling. The conditioning regimen consisted of busulfan and cyclophosphamide. Cyclosporine A and short term methotrexate were administered prophylactically for graft-versus-host disease (GVHD). She developed slight veno-occlusive disease and pancytopenia, which improved soon. She is surviving free of disease for 37 months from BMT. Case 2: A 41-year-old male was diagnosed as having T-MDS AML (M2) and achieved complete remission with the AML89 protocol, but relapsed soon. He underwent allo-BMT from an HLA-identical sibling. The conditioning regimen and prophylaxis against GVHD were the same as in case 1. He developed mild acute GVHD, pleural effusion and later mild chronic GVHD. These improved soon. He is surviving free of disease for 21 months from BMT. Some reports suggest that intensive chemotherapy can induce CR in 40%-70% of patients with T-MDS AML, but most of them tend to relapse and rarely survive long. We consider that the best strategy for treatment of T-MDS AML is allo-BMT at present, if suitable donors are available.

Adult↗
PubMed1994

[Symptomatic Rathke's cleft cyst: a clinicopathologic study of 9 cases].

Nine cases of symptomatic Rathke's cleft cyst are reported. Their most frequent signs and symptoms included headache, chiasmal syndrome and hypopituitarism, while one of the cases developed a sudden onset of headache and vomiting following diabetes insipidus. Endocrinological findings showed a decreased ACTH, gonadotropin and growth hormone more frequently while there were 2 cases of hyperprolactinemia and 1 case of diabetes insipidus. In a neuroradiological examination, a plain skull X-ray showed 5 cases of ballooning of the sella turcica, and a CT scan demonstrated a low to high density of the cyst and 2 cases of marginal enhancement of the cyst. MRI mostly demonstrated a well delineated mass at the sella extending mostly into the suprasellar region and a low to high intensity of the cyst in the T1-weighted image. Two cases were marginally enhanced after gadolinium DTPA administration. The pathological examination, done on 6 cases, showed either single or multiple layers of the epithelium which were mostly ciliated. The epithelium was positive in PAS and Alcian blue in all cases and a histochemical examination showed 3 cases to be positive in EMA and 2 cases positive in CEA. A resection of the cyst wall and an opening of the cyst is thus recommended in symptomatic cases. Therefore, the transsphenoidal approach should be the choice of treatment in an intra- and suprasellar extension of the cysts with sellar enlargement.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Randomized study of individualized induction therapy with or without vincristine, and of maintenance-intensification therapy between 4 or 12 courses in adult acute myeloid leukemia. AML-87 Study of the Japan Adult Leukemia Study Group.

BACKGROUND: It was assessed whether addition of vincristine (VCR) to remission induction therapy would increase the complete remission (CR) rate, and, secondarily, whether 12 courses of maintenance-intensification therapy would produce longer survival than 4 courses in adult acute myeloid leukemia (AML). METHODS: A randomized comparison of individualized induction therapy was conducted between daunorubicin, behenoyl cytarabine, 6-mercaptopurine, and prednisolone with or without VCR. After 3 courses of intensive consolidation therapy, maintenance-intensification therapy was randomized to 4 or 12 courses given every 6 weeks. RESULTS: Of 265 patients registered, 252 were evaluable. CR was obtained in 78%; 80% in 205 patients of age younger than 60 years, and 65% in 47 of age 60 years or older. Addition of VCR reduced the CR rate significantly (84% to 70%, P = 0.007). Predicted 4-year survival, continuing CR, and disease-free survival (DFS) rates of 196 CR patients are 45%, 41%, and 35%, respectively. Patients receiving 12 courses of maintenance-intensification showed better DFS. By multivariate analyses, significant factors for achievement of CR were performance status 0 to 2, age younger than 60 years, and no VCR; and those for longer DFS were achievement of CR by one course, age younger than 50 years, and French-American-British (FAB) classification M3 or M5. Among 131 patients randomized to the maintenance, the administration of 12 courses was the most important factor (P = 0.0040) for longer DFS, followed by FAB M3 or M5, and by achievement of CR by one course. CONCLUSIONS: Addition of VCR in remission induction therapy was harmful, and longer intensive maintenance therapy prolonged DFS in adult AML.

Acute Disease↗
PubMed1993

Aqueductal stenosis due to mesencephalic venous malformation: case report.

The authors report the case of a 43-year-old woman with a venous malformation of the mesencephalon occluding the sylvian aqueduct. Neuroradiological investigations suggested aqueductal stenosis, while the presence of a venous malformation was diagnosed by both magnetic resonance imaging and an angiogram, and was visualized using a neuroendoscope. This is the first reported instance of a venous malformation being observed in situ and the subependymal course taken.

Adult↗
PubMed1993

An observation of the third ventricle under flexible fiberoptic ventriculoscope: normal structure.

The third ventricle, which is deeply seated in the center of the brain, is one of the most inaccessible regions from which to obtain information before surgery. A new flexible fiberoptic endoscope for examination of the ventricles is presented herein. The main advantages of this new device over existing fiberoptic instruments are the extended flexibility of the tip and its small diameter. Using this endoscope, one can observe the third ventricle in situ in patients with hydrocephalus associated with various lesions. The neural and vascular structures in the inner wall of the third ventricle are also illustrated.

Cerebral Ventricles↗
PubMed1993

Use of multiple-alternative matching-to-sample in the study of visual search in a chimpanzee (Pan troglodytes).

Visual search in a chimpanzee (Pan troglodytes) and in humans (Homo sapiens) were compared under the multiple-alternative matching-to-sample (MTS) procedure, in which a sample stimulus was followed by one positive (target) and several negative comparison stimuli (distractors). Reaction times in the chimpanzee were affected by the number of distractors, the target-distractor similarity, and the uniformity of search display. Similar results were also obtained from humans and suggest that the performance by the chimpanzee may involve the same visual information-processing capabilities as those required in the human visual search performance. The multiple-alternative MTS is useful for studying various visual perceptual-cognitive abilities of animals including chimpanzees.

Animals↗
PubMed1993

A unique case of t(15;17) acute promyelocytic leukaemia (M3) developing into acute myeloblastic leukaemia (M1) with t(7;21) at relapse.

This report describes a case of t(15;17) acute promyelcytic leukaemia (APL, FAB subtype M3) with dysgranulopoiesis at diagnosis in a patient who developed myelodysplasia (MDS) and then a second phenotype of t(7;21) acute myeloblastic leukaemia (AML, FAB subtype M1) at the time of relapse. To our knowledge, there is no report of a second phenotype of AML occurring after complete remission (CR) of APL. Furthermore, this is the first report of chromosomal abnormality t(7;21) in a case of AML. Several hypotheses for this unusual course of APL are discussed.

Bone Marrow↗
PubMed1993

Analysis of BCR/ABL abnormalities in mRNA from 20-year-old paraffin-embedded tissue for BCR/ABL rearrangement by polymerase chain reaction.

We studied whether it is possible to obtain sufficient mRNA from old paraffin-embedded samples of spleen and bone marrow for reverse transcription and polymerase chain reaction analysis. Spleen tissue from 6 subjects with chronic myelogenous leukemia was studied for rearrangement of BCR and ABL genes. Analysis was successful in 4 cases. These data indicate the feasibility of retrospective analysis of tissue samples of special interest by molecular techniques.

Adult↗
PubMed1993

Flexible endoneurosurgical therapy for aqueductal stenosis.

We successfully managed 11 patients with aqueductal stenosis of adult or adolescent onset, with no mortality or significant morbidity, by using a flexible ventriculoscope to perform either a third ventriculostomy or an aqueductal plasty. A flexible fiberoptic ventriculoscope and its accessories were newly developed, and surgical techniques were improved. For all patients, cinemagnetic resonance imaging was a critical part of the preoperative and postoperative evaluation of cerebrospinal fluid flow in the third ventricle and in the aqueduct of Sylvius. All of the 11 patients showed patency to cerebrospinal fluid flow at the aqueduct of Sylvius and the floor of the third ventricle. Only one patient subsequently required a lumboperitoneal shunt. Flexible endoneurosurgical management is simple and safe and allows in situ observation and the ability to perform biopsies. Therefore, flexible endoneurosurgical third ventriculostomy and aqueductal plasty are now considered our treatment of choice for aqueductal stenosis in adults and adolescents.

Adolescent↗
PubMed1993

Extracranial aneurysm of the posterior inferior cerebellar artery: case report.

The authors report the unusual case of an aneurysm arising from the extracranial portion of the left posterior inferior cerebellar artery (PICA). The patient was a 39-year-old woman who developed a subarachnoid hemorrhage. The hemorrhage was in the basal, ambient, and Sylvian cisterns, but not in the ventricles. There were no focal neurological deficits, and the clinical grading was 1. On cerebral angiograms, the PICA was found to originate from the vertebral artery as low as 17.9 mm below the foramen magnum and to enter into the spinal canal through the intervertebral foramina of C1-C2. The artery went up to the posterior fossa and had only the cranial loop with an absence of the caudal loop. The saccular aneurysm hung on the initial segment of the PICA and was located at the C1 level. The patient developed motor aphasia and hemiparesis on the right side 15 days after onset, and an infarction was disclosed in the boundary zones of the left parietal lobe on a computed tomographic scan. The aneurysm was successfully obliterated by a neck clipping 2 months later, and the patient was discharged in good condition. The literature discussing PICA aneurysms in the extracranial, as well as distal, portion is reviewed.

Adult↗
PubMed1993

Tests for control by exclusion and negative stimulus relations of arbitrary matching to sample in a "symmetry-emergent" chimpanzee.

In the present experiments, controlling relations in arbitrary matching-to-sample performance were tested in a 9-year-old female chimpanzee who showed statistically significant emergence of symmetry in previous two-choice conditional discrimination experiments. In Experiment 1, a novel (undefined) sample stimulus was followed by a pair of trained (defined) and undefined comparison stimuli to assess the control by exclusion in arbitrary matching. The chimpanzee selected the undefined shape comparison, excluding the defined one, in color-sample-to-shape-comparison probe trials, although stimulus preferences were relatively stronger than control by exclusion in shape-sample trials. An additional test for control by relations of the sample to the positive comparison (S+ control) showed that her behavior was also under the control of relations of the sample to the positive comparison. In Experiment 2, a defined sample was followed by a pair of negatively defined and undefined comparisons to test control by the relations of the sample to the negative comparison. (S- control). The subject selected undefined comparisons in both color-shape and shape-color test trials. These results clearly indicate that the conditional discrimination behavior of this "symmetry-emergent" chimpanzee was under both S+ and S- control. Furthermore, her performance was also under control by exclusion in color-shape arbitrary matching, unlike other chimpanzees who showed no evidence of symmetry but only S+ control of arbitrary matching.

Animals↗
PubMed1993

Detection of monoclonal hematopoiesis using restriction fragment length polymorphism (RFLP) of phosphoglycerokinase (PGK) gene in a patient with hypoplastic myelodysplastic syndrome (MDS).

A clonal analysis of hematopoiesis in a hypoplastic MDS patient was performed. Monoclonal utilization of PGK gene on her two X chromosomes was detected by Southern blot analysis of the bone marrow cells using a PGK probe after methylation-sensitive restriction enzyme treatment. This is compatible with monoclonal construction of her hematopoiesis, confirming MDS nature with a progression of her morphological dysplasia in bone marrow cells. RFLP of PGK gene on X chromosome is thus useful to detect a monoclonality in hematopoietic diseases.

Adolescent↗