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Biomedical subjects

R Tanaka

Publications and source records attributed to R Tanaka.

At least 757 records · Page 42Linked to original sources

[Multiple cerebrovascular occlusive disease associated with neurofibromatosis].

Multiple cerebrovascular occlusive disease is rarely seen in patients with neurofibromatosis. Two cases of such lesions are presented and literatures dealing with the clinical and angiographical aspects of this occlusive disease are reviewed. Case 1; A 38-year-old normotensive man had sudden onset of vomiting, left hemiparesis and disturbance of consciousness, one day before the admission. He had family history of neurofibromatosis, and examination showed café au lait spots over the body. CT scans revealed a subcortical hematoma in the right temporal lobe. Angiogram revealed multiple occlusive lesions of the cerebral arteries, including occlusions of the right internal carotid artery (ICA) at the distal end, middle (MCA) and anterior (ACA) cerebral artery at the proximal portion, and stenosis of the left ICA and ACA. Abnormal vascular networks at the base of the brain were also seen bilaterally. Decompressive craniectomy, removal of the hematoma and bilateral ventricular drainage were performed. Postoperative course was excellent. Angiogram performed five and a half years later, during which time without any surgical procedures, demonstrated no apparent angiographic differences from the previous one. Case 2; A 29-year-old woman without family history of neurofibromatosis presented with sudden onset left hemiparesis. Café au lait spots were found over the body. A CT scan revealed small infarctions in the territory of the right MCA, and angiogram demonstrated multiple occlusive lesions of the cerebral arteries, including stenosis of the bilateral ICA, the left MCA, both ACAs at the proximal portion, and the right posterior cerebral artery, and occlusions of the right MCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Case of cerebral aneurysm producing the aberrant regeneration of the oculomotor nerve].

We reported a 61-year-old woman who developed the associated movements in oculomotor muscles after the clipping of the IC-PC aneurysm which had produced the oculomotor palsy. It has generally been assumed that the phenomenon is the result of an aberrant regeneration of oculomotor nerve fibers. The sign of the aberrant regeneration may include any of the following: Pseudovon Graefe sign: retraction and elevation of the lid on downward gaze. Gaze lid dyskinesis: elevation of the involved lid on adduction of the eye. Inability to elevate or depress the globe: the globe neither elevates nor depress in up or down gaze. Retraction of the globe: the globe can be seen to retract on vertical movement. Adduction of the involved eye on attempted depression or elevation. Pseudo-Argyll Robertson pupil: the dilated pupil will not react to light but will contract when the medial rectus, inferior rectus, or elevators of the eye are stimulated. Monocular optokinetic response: in testing the vertical optokinetic response, the normal eye responds as usual but the affected eye either remains stationary or will show a slight horizontal nystagmus. All but category 4 were noted in our case.

Female↗

Blast crisis of chronic myelogenous leukemia with tumor formation characterized by T-cell features--a case report.

We report a case of chronic myelogenous leukemia (CML) associated with pronounced peripheral lymphadenopathy, with the cells having the philadelphia (Phl) chromosome and T-cell features. A 23-year-old man who was diagnosed as having CML and treated with busulfan was admitted to our hospital because of increasing hepatosplenomegaly and pronounced lymphadenopathy. An axillary lymph node biopsy disclosed that the malignant cells formed rosettes with neuraminidase-treated sheep red blood cells (En) (95.0%) and were positive for Leu 1 (91.8%). Of the cytochemical reactions, peroxidase was negative and periodic acid-Shiff, acid alpha-naphthyl acetate esterase and beta-glucuronidase were all positive. The karyotype of the bone marrow cells was 46 XY Phl positive (22q-), and that of the lymph node cells was 51 XY Phl positive +8, +9, +18, +19, +21, 22q-. He was treated with various anti-leukemic agents and irradiation. Despite such treatments, he died of pneumonia. This is a report of a CML patients with blast crisis and tumor formation characterized by T-cell features.

Adult↗

Cerebral hemodynamics in patients with moyamoya disease. A study of the epicerebral microcirculation by fluorescein angiography.

Fluorescein angiography was performed in 12 hemispheres of eight young patients with moyamoya disease to study the epicerebral microcirculation. Regional circulation time and the time interval between carotid injection of the dye and first filling of the cortical arteries were various and prolonged in the most parts. There were nonfilling areas by carotid injection of the dye in six hemispheres. By venous injection, the dye appeared in all vessels of the exposed areas. Extravasation of the dye was seen in four hemispheres. The degree of these abnormalities of the epicerebral microcirculation was well correlated with the findings in conventional cerebral angiography.

Adolescent↗

Scanning electron microscopy of experimentally induced hepatocellular carcinoma.

Hepatocellular carcinomas (HCC) induced in rats by diethylnitrosamine were observed by light microscopy (LM) and scanning electron microscopy (SEM). Liver cirrhosis did not develop. The tumors were of 4 types; trabecular, glandular, adenoid and hyperplastic nodular (HN). SEM demonstrated that trabecular lesions were packed with many layers of HCC cells which had in some places bile canaliculi on the intercellular surfaces with sparse microvilli. Glandular lesions were composed of gland-like structures having columnar or cuboidal cells with numerous microvilli on the hemispherical apex. Glandular lumens were bordered from intercellular spaces by the zona occludens. The glandular structures were derived from the exterior of the trabecular lesions and were closed at both ends, as confirmed by reconstruction of serial sections. Adenoid lesions, which had gland-like structures in the trabecula, were often observed between purely trabecular and purely glandular lesions. HN-type lesions composed of two-cell-thick plates were mostly located at the peripheral parts of the HCC tumor and were continuous with other lesions. HN-type lesions had markedly dilated bile canaliculi and well-developed microvillous projections on the intercellular surfaces. The HN-type lesions had structures similar to those of late HN. The existence of lesions indistinguishable from late HN in the periphery of HCC tumors indicates the HCC develop from HN. In summary, the rat HCC were of 4 types of lesions which had characteristic histological and cytological structures, but which were connected with each other, changing gradually from one to the other.

Animals↗

Scanning electron microscopy of experimentally induced sequential alterations of rat liver hyperplastic nodules.

Rat liver hyperplastic foci (HF) and hyperplastic nodules (HN) induced by diethylnitrosamine (DEN) according to the method of Solt and Farber were observed by light microscopy (LM) and scanning electron microscopy (SEM). Liver cirrhosis was not observed. HF, which were composed of basophilic hepatocytes arranged usually in two-cell-thick plates and occasionally one-cell-thick plates, were followed by early HN, which were composed of eosinophilic hepatocytes with enlarged nuclei and prominent nucleoli, at 4 weeks after DEN administration. SEM revealed that hepatocytes in HF had smooth surfaces and dilated bile canaliculi with a few short microvilli. Early HN (4 and 6 weeks) were composed of two-cell-thick plates of hepatocytes, whose intercellular surfaces were covered with numerous microvillous projections. Bile canaliculi were dilated and had numerous short microvilli. Late HN (6 and 8 months) were composed of eosinophilic hepatocytes, which were irregular in shape and size. Their nuclei were enlarged and nucleoli were prominent. Hepatocytes were arranged in two-cell-thick plates, but never in many-cell-thick plates. Bile canaliculi were larger than sinusoids. The bile canaliculi had numerous diverticula, but the zona occludens was present. Microvillous projections of intercellular surfaces of hepatocytes were more numerous than those of early HN. Fenestrae of the sinusoidal endothelium were lost in most parts. Kupffer cells were not seen in any stage of HN. HN progressed gradually toward hepatocellular carcinoma.

Animals↗

Inhibition of glia maturation factor-induced mitogenesis in glioblasts by calmodulin antagonists.

The growth inhibitory activity of calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) and trifluoperazine (TFP), was analyzed by the use of rat fetal glioblasts stimulated by glia maturation factor (GMF) or rat astrocytoma cells (C6). The inhibitory effect of W-7 on GMF-induced DNA synthesis of glioblasts was apparent when the drug was added within 10 h after the stimulation by GMF (late G1 phase), but was not shown when W-7 was added at 12 h or later (S phase). The intracellular calmodulin content was built up concurrently with the increase in the DNA synthesis in S phase. The half-maximal inhibition (ID50) of GMF-induced DNA synthesis in glioblasts was observed at 16.5 microM of W-7 or 9.0 microM of TFP. ID50 of DNA synthesis in exponentially growing C6 cells was approximately 3 times higher than that in glioblasts: 24 microM of TFP and as high as 40 microM of W-7. ID50 of growth rate of C6 cells was 15 microM of TFP which was comparable to the ID50 dose for the inhibition of DNA synthesis. Both calmodulin antagonists and W-5, a dechlorinated analog of W-7, however, elicited a curious activation of DNA synthesis of glioblasts at low concentrations (lower than 10 microM of W-7 and W-5, or lower than 5 microM of TFP), indicating non-specific effects of calmodulin antagonists on DNA synthesis. These results suggest that calmodulin antagonists have two conflicting effects on DNA synthesis: the stimulation of DNA synthesis at lower concentrations, and inhibition at higher concentrations.

Animals↗

Characterization and partial purification of neuroblastoma growth inhibitory factor from the culture medium of glioblasts.

Neuroblastoma growth inhibitory factor (NGIF) exists in the conditioned medium of normal rat glioblasts. When neuroblastoma cells (Neuro2a, NS-20Y, and N1E-115) were cultured in the presence of the factor, the cell growth rates and DNA synthesis were markedly inhibited and the morphological differentiation including neural process formation was induced. However, the factor neither altered the growth rate nor the morphology of non-neuronal cells such as glial cell lines (C6 and 354A) or fibroblast (3T3). The molecular weight of the factor was estimated to be 75,000 Mr by gel filtration with Bio-Gel P-200, and the isoelectric point was 5.8. The factor was devoid of esteropeptidase activity, and susceptible to protease and thermal treatment. The growth inhibitory action of the factor was unrelated to the intracellular contents of cyclic AMP and GMP. The ability of NGIF to suppress preferentially the neural growth suggests its regulatory role in normal brain development.

Animals↗

Rupture of anterior communicating artery aneurysm during transsphenoidal surgery for pituitary adenoma.

The case of a 55-year-old man with a nonfunctioning pituitary adenoma associated with an anterior communicating artery aneurysm that ruptured during transsphenoidal surgery is presented. This small aneurysm was not detected on bilateral angiography of the carotid artery before surgery. Computed tomography (CT) scans showed the pituitary adenoma extending to the suprasellar region and the sphenoid sinus. After intracapsular removal of the tumor, cerebrospinal fluid from an intraspinal catheter became bloody and CT scans disclosed massive subarachnoid hemorrhage. Repeated angiography revealed a tiny anterior communicating artery aneurysm, which was clipped on the 37th day after the operation. Risk factors in the procedure of transsphenoidal surgery, especially of a pituitary adenoma with suprasellar extension, are discussed.

Adenoma↗

Computed tomographic demonstration of the effect of proximal parent artery ligation for giant intracranial aneurysms.

Four patients with giant intracranial aneurysms, which measured over 2.5 cm in diameter, were treated by ligation of the proximal parent artery. The location of the aneurysms were intracavernous in two patients, paraophthalmic in one patient, and vertebral in the other patient. The effect of ligation was followed by repeated computed tomography scans with angiographic correlation. The aneurysms thrombosed soon after ligation, and with time, gradually organized with a reversal of the mass effect. Five years after the ligation, one aneurysm thrombosed completely and lost its mass effect upon the adjacent structures. For giant aneurysms treated with ligation of the proximal parent artery, computed tomography scans are a useful method for continuing review, producing precise information concerning actual size, thrombus formation, and various pathological changes.

Adult↗

Bacteriophage distribution in human faeces: continuous survey of healthy subjects and patients with internal and leukaemic diseases.

In order to elucidate the ecological role of bacteriophages in the human intestine, we analysed the numbers of coliphages and of coliphage strains present in faecal samples collected from healthy individuals and from patients with certain intestinal diseases. The isolated phages were grouped according to their serological properties. The samples with low phage titres, observed in both healthy subjects and patients, contained mainly temperate phages (many were related to phi 80 and lambda), and those with higher titres, observed in patients, contained virulent phages. From successive surveys of coliphages and their host, Escherichia coli, in faecal samples of each subject, it was concluded that temperate phages are maintained in the human intestine through spontaneous induction of lysogenic bacteria. Qualitative and quantitative differences existed between phages isolated from faecal samples from healthy subjects and from patients. Simultaneous changes in the distribution patterns of coliphages and of the clinical symptoms were observed in a continuous survey of a leukaemic patient in a protective environmental ward.

Coliphages↗

Simultaneous occurrence of acute myelogenous leukaemia and multiple myeloma without previous chemotherapy.

A patient with simultaneous occurrence of multiple myeloma and acute myelogenous leukaemia without previous chemotherapy was studied. Indirect immunofluorescence and protein A-coupled ox red blood cells rosette technique by use of anti-idiotype (Id) antibody showed some T cells with receptors of idiotypic specificity identical with that of the secreted myeloma protein. Plaque forming cell assay showed the presence of Id producing peripheral blood lymphocytes with EB virus receptor, probably B cells. These observations strongly suggest that multiple myeloma was not the result of a neoplastic transformation of the most differentiated B cells, plasma cell, but of lymphoid stem cells capable of differentiating to either B or T cells. However, there was not a detectable population of myeloblasts that expressed the same idiotype. Chromosomal analysis revealed a deletion of the long arm of chromosome 8 in myeloblasts but not in T or B cells. These results support the hypothesis of separate clonal origins for the leukaemic and myeloma components in this case.

Aged↗