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O Tanaka

Publications and source records attributed to O Tanaka.

At least 19 recordsLinked to original sources
PubMed1995

Magnetic resonance imaging of femoral marrow in patients with myelodysplastic syndromes or leukemia.

We evaluated magnetic resonance imaging (MRI) of femoral marrow in 85 untreated adult patients with myelodysplastic syndromes (MDS) (N = 27), aplastic anemia (N = 9), and leukemia (N = 49). Images of femoral marrow were obtained using a T1-weighted spin-echo (SE) method and a short T1 inversion recovery (STIR) technique. In patients with MDS, the change in MRI pattern from a fatty or nodular pattern to a uniform pattern correlated with disease progression. Evolution to acute leukemia in MDS patients was associated with a higher signal intensity on STIR images (lower signal intensity on T1-weighted SE images) and an extended area of involvement. The femoral marrow in patients with de novo acute myeloid leukemia (AML) showed increased signal and varied patterns (scattered to uniform) on STIR images. However, the faint pattern (grade 4a) was characteristic of M2 AML. In patients with chronic myelogenous leukemia (CML) in the chronic phase, increased leukemic mass was represented by replacement of the femoral marrow with a region of abnormal signal intensity. The extent of involved areas in these CML patients correlated with the spleen size. This study indicates that MRI of femoral marrow is an important tool for the accurate diagnosis and management of patients with MDS and leukemia that may function as an adjunct to bone marrow aspiration and biopsy.

Adipose Tissue↗
PubMed1995

Ultrastructure of developing muscle in the upper limbs of the human embryo and fetus.

BACKGROUND: The ultrastructure of the myogenesis, which proceeds along with the appearance of muscle-specific proteins and isozymes, has not been fully described in the upper limb of staged human embryos. METHODS: Eight human embryos (Carnegie stage 14-22) and two fetuses (11 and 12 weeks of gestation) were fixed with 5% glutaraldehyde, 4% paraformaldehyde, and 0.2% picric acid in 0.1 M phosphate buffer, pH 7.2. The upper limbs were dissected out and processed for transmission electron microscopy, and sections of the biceps brachii muscle were cut and examined. RESULTS: At stage 14, the myoblasts were loosely scattered in the ventral proximal region of the upper limb bud and had a small amount of cytoplasm with a few intracellular organelles. At stage 16, the myoblasts were spindle shaped and oriented parallel to the axis of the upper limb bud. These cells had irregularly shaped nuclei with prominent nucleoli, rough endoplasmic reticulum (ER), and mitochondria, but no myofilaments were observed. At stages 17-19, rough ER, free ribosomes, and mitochondria increased in number and thick and thin filaments with faint Z-lines appeared in the peripheral cytoplasm of the myotube. The plasma membranes of some neighboring myotubes were continuous, suggesting that these cells were in the initial stages of the fusion process. At stage 22, the striated pattern of the myofilaments became evident and tubular structures appeared around them and near the plasma membrane. In the fetus at the 11th week, the basal lamina began to surround the myotubes, and T-tubules with sarcoplasmic reticulum were observed. Dyads and triads were observed in the myotube of the 12th week fetus. CONCLUSION: These findings suggest that rapid myogenesis occurs during the late embryonic period in human upper limbs and that the ultrastructural characteristics of mature myotubes are established during the early fetal period.

Arm↗
PubMed1995

Histochemical differences of the lectin affinities of backbone polylactosamine structures carrying the ABO blood group antigens in papillary carcinoma and other types of thyroid neoplasm.

Endo-beta-galactosidase from Escherichia freundii cleaves linear polylactosamine structure as follows: R-GlcNAc-beta 1-3Gal-beta 1-4GlcNAc-beta 1-R' + H2O-->R-GlcNAc-beta 1-3Gal + GlcNAc-beta 1-R'. Staining with Griffonia simplicifolia agglutinin II (GSA-II) following enzyme digestion reveals the distribution of R-GlcNac-beta 1-3Gal-beta 1-4GlcNAc-beta 1-R' structures in tissue sections. In this study, the procedure was applied to formalin-fixed, paraffin-embedded tissue sections from 26 cases of papillary carcinomas including 2 follicular variants, 8 follicular carcinomas, 7 adenomas, 1 anaplastic carcinoma and 1 medullary carcinoma in order to investigate whether different types of polyactosamine-containing structure are produced in these thyroid neoplasms. Simultaneously, the susceptibility of the ABH antigens expressed in these neoplastic cells to endo-beta-galactosidase digestion was examined. Most of the papillary carcinoma cells from all the individuals examined were strongly stained by GSA-II following enzyme digestion. Without enzyme digestion, little or no reactivity with GSA-II was observed. Among other types of neoplasms, only one case of follicular carcinoma exhibited reactivity with GSA-II following enzyme digestion. ABH antigens were expressed in 22 cases of papillary carcinomas, 2 adenomas, 5 follicular carcinomas and 1 anaplastic carcinoma, and their expression was dependent on the ABO blood group of the patients. Endo-beta-galactosidase digestion resulted in the elimination of these antigens not only in papillary carcinomas but also in other neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)

ABO Blood-Group System↗
PubMed1995

Electrogastrography prior to and following total gastrectomy, subtotal gastrectomy, and gastric tube formation.

On electrogastrography (EGG) spectral analysis, an activity of 3 cycles per minute (cpm) is supposed to be specific for the stomach. After total or subtotal gastrectomy, the original site of the stomach is occupied mainly by the intestine. We attempted to determine if intestinal activity could be recorded in this region with EGG. Epigastric recordings were performed in patients prior and following gastrointestinal or control surgeries. Spectral analysis, using the maximal entropy method and ensemble means was applied to data analysis from these recordings. Preoperatively, the majority of the power peaks were found around 3, 6, and 11 cpm. The postprandial-to-fasting power ratio of all of these power peaks increased significantly postprandially (P < 0.05-0.01). Following total gastrectomy, the power peak around 3 cpm disappeared or was significantly diminished in amplitude (P < 0.05). The postoperative-to-preoperative power ratio ranged from 0.03 to 0.10 (P < 0.001-0.01). However, the power peak around 11 cpm did not significantly change prior to or following total gastrectomy, and the 11 cpm peak appeared relatively dominant. Simultaneous manometric studies in the Roux limb demonstrated a correlation between the power spectral frequency of EGG and manometry at 11 cpm. Therefore, the 11 cpm peak appeared to reflect jejunal or Roux limb electrical activity. The postoperative to preoperative power ratio for the 3 cpm also was significantly reduced following subtotal gastrectomy and gastric tube formation in patients in the postprandial state (P < 0.05-0.001).

Adult↗
PubMed1995

Localization of mRNAs of voltage-dependent Ca(2+)-channels: four subtypes of alpha 1- and beta-subunits in developing and mature rat brain.

The heterogeneous gene expression for four subtypes of alpha 1 (A,B,C,D)- and beta (beta 1,beta 2,beta 3,beta 4)-subunits of voltage-dependent calcium channels was demonstrated in developing and adult rat brain by in situ hybridization histochemistry. In the adult rat brain the gene expression for A- and B-subtypes was predominant in the cerebellar cortex and hippocampal neuronal layers, with the A-subtype expressed most intensely in the Purkinje cells, while the expression for C- and D-subtypes was predominant in the olfactory mitral and granule cells and the dentate granule cells. The expression of beta 1-mRNA was prominent in the olfactory mitral cells and dentate granule cells whereas that of beta 2-mRNA was evident in the hippocampal neuronal layers and cerebellar Purkinje cells. The expression of beta 3-mRNA was prominent in the olfactory mitral and internal granule cells and medial habenula, whereas that of beta 4-mRNA in the olfactory mitral cells and cerebellar Purkinje and granule cells. Comparison between the expression patterns for individual alpha- and beta-subunits suggests that the beta 4-subunit contributes to P-type channel, whereas the beta 1- and beta 3-subunits contribute respectively to D- and C-subtypes of L-type channels, although dissociation in the expression patterns were also noted in several brain regions. In addition to neuronal populations, the gene expression for the C-subtype of L-type channel was detected at substantial level in glial cells. In developing brains, the genes for the all subtypes of alpha 1- and beta-subunits were expressed in the mantle zones, but not the ventricular zones, of the entire neuraxis and the expression was more or less attenuated during early postnatal periods in most of the brain regions except for the olfactory bulb, hippocampus and cerebellar cortex, suggesting that the Ca(2+)-channels are intimately involved in the neuronal differentiation.

Age Factors↗
PubMed1995

Chemotherapy of human small-cell gastrointestinal carcinoma xenografts in nude mice.

We established two xenografts of small-cell carcinoma (SCC) arising in the oesophagus or the stomach, designated TEG13 and TSG15, and investigated the responses to experimental chemotherapy on these strains. Both tumours were classified as the intermediate cell type of SCC composed of small cells having neuroendocrine features in terms of morphology, argyrophil property, and immunoreactivity for neuron-specific enolase. Mitomycin C, cisplatin, and cyclophosphamide were judged to be effective against both strains. Particularly, cisplatin produced almost complete regression of tumour growth of the TEG13 strain. Etoposide proved effective only against the TSG15 strain. Moreover, the combined treatment with etoposide and cisplatin produced the most pronounced antitumour effect against the TSG15 strain. These studies suggest that cisplatin may be a key drug for chemotherapy of oesophageal SCC, and etoposide plus cisplatin treatment may be especially recommended in the treatment of gastric SCC. Mitomycin C should be re-evaluated in gastrointestinal SCC.

Aged↗
PubMed1995

Relationship between associations of NOR and chromosomal anomalies in the abnormal embryos of nonobese diabetic and STZ-diabetic mouse.

Associations of nucleolar organizing regions (NORs) in the postimplantation stage embryos of nonobese diabetic (NOD) mice, and diabetic ICR mice induced by streptozotocin (ST), were studied to investigate the possible cause of the numerical anomalies of the chromosomes in their abnormal embryos. The incidence of NOR associations in abnormal embryos from diabetic NOD (NOD-DM) and STZ-diabetic mice was 11.7 and 7.7%, respectively. This incidence was significantly higher than that (1.2%, p < 0.05) of normal embryos from ICR mice which were used as control. From the results analyzed cytogenetically it was suggested that the higher incidence of chromosomal numerical anomalies in the embryos from NOD-DM and STZ-diabetic mice were caused by the chromosomal nondisjunction induced by associations of NORs. Furthermore, it was suggested that NOD-DM embryos have a tendency to increase the associations of NOR in a diabetic condition together with other factors such as autoimmune disease, however a diabetic condition alone induced chromosomal anomalies. Regarding relationships between the incidence of associations of NOR and the types of malformed embryos, it was also clear that all of the abnormal embryos from NOD-DM and STZ-diabetic mice had a high incidence of associations of NOR, and that the incidence was not related to the types of congenital anomalies. Furthermore, in the mal-developed tissue of embryos from STZ-diabetic mice, many chromosomal anomalies were found (26.6%), and the incidence was similar to that of whole embryos (22.6%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Long-term results of surgical treatment of intracardiac tumors. Effectiveness and limitation of surgical treatment.

Twenty-five cases of intracardiac tumors were operated upon from 1975 through 1994. Twenty-four operative survivors were followed up. The follow-up period ranged from 2 months to 19 years with an average of 8 years. The histological diagnoses of the tumors were as follows: benign tumors 21 (myxoma 20, leiomyoma 1) and malignant tumors 4 (sarcoma 3, carcinoma 1). In 21 cases, tumors had cardiac origins, while there were four intracardiac tumors which had originated in other organs and extended transvenously to the intracardiac cavity (leiomyoma 1, sarcoma 2, carcinoma 1). The results of surgical treatment of intracardiac benign tumors were satisfactory, regardless of their origins and multiplicity, both in the short-term and in the long-term. On the other hand, the long term results for malignant intracardiac tumors were extremely poor, although their excision or resection had a beneficial effect on the hemodynamics in patients with congestive heart failure or cardiogenic shock.

Adult↗
PubMed1995

Vestibulocochlear defects and effects of deuterium oxide in mutant bustling (BUS) mice.

Bustling mouse (BUS/Idr: bus) is a mutant mouse strain which exhibits bustling/hyperkinetic behavior and functional disorders related to the vestibulocochlear system such as rapid circling and loss of auditory startling response. In homozygous (bus/bus) mice this phenotype develops progressively after birth and has been shown from cross experiments to be inherited by a single autosomal recessive gene. Using light and electron microscopy, we examined the development of pathological changes in the inner ear of homozygous mice. Effects of deuterium oxide, which has been shown to influence vestibular function, on the abnormal behavior of homozygous mice of different ages were also examined. Pathological changes of the inner ear including impairment and/or loss of auditory hair cells, deformation and/or loss of the inner and outer tunnels of the organ of Corti, hypoplasia of the otoliths, and decrease in number of neurons of the spiral genglion were observed in the homozygous mice starting before the weaning stage and progressively thereafter, but not in the heterozygous mice. Although histological changes were also noted in the crista ampullaris and maculae, they were less evident than those in the cochlea at least until the mice were 6 weeks old. Administration of deuterated physiological saline (8-16 ml/kg, per os) tended to decrease the abnormal behavior of the homozygous mice, including rapid circling. These morphological and functional findings suggest that BUS mice may be a useful model for analysis of the pathogenesis of vestibulo-cochlear disorders.

Animals↗
PubMed1995

Opaque eyes developed in transgenic mice with T-cell receptor delta gene.

PURPOSE: During the generation of transgenic mice (TGs) introduced with mouse T-cell receptor delta (TCR delta) gene, the authors found a TG line with corneal opacity that coincided with the presence of the transgene. The authors investigated the pathogenesis and molecular mechanisms of this corneal opacity in this line. METHODS: The pathologic features and pathogenesis of the corneal opacity in TGs were examined histologically using transmission and scanning electron microscopy, as well as light microscopy. DNA and RNA blot analyses were performed to examine the copy number and the expression of the transgenes, respectively. RESULTS: Histologically, edema of the corneal epithelium and adhesion of the iris to the cornea were observed in adult TGs. In the developmental analysis, the authors first observed relative hypoplasia of the ciliary body on day 18 of gestation and dysgenesis of the anterior chamber angle from postnatal day 2. Corneal opacity was observed from postnatal day 8, coinciding with the histologic vesicular change of the epithelium. No inflammation was observed through its life. In the sublines that have different copy numbers of the transgene, the occurrence of the opacity depended on the copy number of the transgene. Expression of the transgene in the thymus was consistent with the number of the introduced transgene. CONCLUSION: In a TCR delta TG line, the overexpression of transgenes coincided with abnormal development of the ocular anterior segment and the corneal opacity. Pathogenesis is described, and possible molecular mechanisms are discussed.

Animals↗
PubMed1995

The effects of PSK, a biological response modifier, on congenital ocular abnormalities induced by X-ray irradiation.

The antiteratogenic effects of PSK, a biological response modifier, were examined using histological and developmental analysis. The whole bodies of pregnant mice were irradiated with X-rays and injected with PSK within ten minutes after irradiation on day 7 of gestation (E7). The foetuses on E18 were examined and a high incidence of malformations were observed in X-ray irradiated embryos. Microphthalmia was the most frequent malformation. PSK administration suppressed the X-ray irradiation-induced ocular anomalies in not only the frequency, as deduced by external observation, but also in histopathological changes in the retina, lens, and cornea. In particular, the incidence of lens aplasia was significantly decreased by PSK administration. Developmental analysis using E10 and E13 embryos revealed that the decrease in the incidence of histopathological changes was first observed within 72 hours after PSK administration. In addition, X-ray irradiation-induced early foetal death (E10-13) was also suppressed by PSK administration. The possible mechanisms of the antiteratogenic effects of PSK are discussed.

Abnormalities, Radiation-Induced↗
PubMed1995

[The left-sided atrioventricular replacement of corrected transposition of the great arteries through a left thoracotomy].

In a 17-year-old female with dextrocardia and corrected transposition of the great arteries, whose VSD and PFO had been surgically closed through median sternotomy two years previously, the left-sided atrioventricular valve replacement was performed for its severe insufficiency. The left anterolateral thoracotomy was chosen to have good visual field and to prevent unnecessary dissection of the adhesion. The postoperative course was uneventful.

Adolescent↗
PubMed1994

Localization of mRNAs for three novel members (beta 3, beta 4 and gamma 2) of phospholipase C family in mature rat brain.

In mature rat brain, PLC beta 3 mRNA was detected weakly only in the pituitary gland and the cerebellar Purkinje and granule cells whereas PLC beta 4 mRNA was expressed intensely in the olfactory mitral cells, thalamic nuclei, medial habenula, pituitary gland and cerebellar Purkinje and granule cells. The beta 4 mRNA was also detected discretely in large neurons of presumably cholinergic nature, scattered rather evenly throughout the caudate putamen and diagonal band, although no significant expression was seen in the medium spiny neurons in the caudate putamen, and the hippocampal pyramidal cells and dentate granule cells. PLC gamma 2 mRNA was localized only in the Purkinje and granule cells in the vermal portions of lobules IX and X of the cerebellum, and in the adenohypophysis.

Aging↗
PubMed1994

Contribution of RGD sequence to neuronal migration in developing cerebral cortex.

The RGD sequence (Arg-Gly-Asp) is known to bind integrins and the synthetic RGD tripeptide inhibits cell adhesion and migration of cultured neuronal cells. However, it is not known whether migration of neuronal precursors in vivo during the cortical histogenesis of the mammalian telencephalon depends on the RGD sequence. To examine this possibility, the RGD peptide was injected into the telencephalic vesicle of mouse embryos. A hypoplastic cortical plate was induced and histological analysis and BrdU-immunohistochemistry revealed that the RGD sequence is involved in neuronal migration and proliferation in the telencephalon during formation of the cortical plate.

Amino Acid Sequence↗
PubMed1994

Transgenic mice overexpressing human vasoactive intestinal peptide (VIP) gene in pancreatic beta cells. Evidence for improved glucose tolerance and enhanced insulin secretion by VIP and PHM-27 in vivo.

Vasoactive intestinal peptide (VIP), a 28-amino acid peptide hormone, plays many physiological roles in the peripheral and central nervous systems. It has been proposed that endogenous VIP released from VIP-containing nerves is involved in the regulation of the secretory function of the endocrine pancreas. To test this hypothesis in vivo, we produced transgenic mice carrying the human VIP/peptide histidine methionine 27 (PHM-27) gene under the control of insulin promoter. In immunohistochemical analyses of islets, all the islet beta cells of transgenic mice were intensely stained for both VIP and PHM-27, consistent with the fact that these two peptides are encoded in a single mRNA (Itoh, N., Obata, K., Yanaihara, N., and Okamoto, H. (1983) Nature 304, 547-549). VIP was efficiently secreted from isolated transgenic islets in vitro. The blood glucose assays in free-fed mice indicated that the transgene lowered the blood glucose levels of transgenic mice (128 +/- 4 mg/dl) by about 20% below control levels (155 +/- 6 mg/dl). In the glucose tolerance test, at 60 min after glucose administration, the transgenic blood glucose levels (129 +/- 12 mg/dl) were much lower than control levels (175 +/- 13 mg/dl). The transgenic serum insulin levels at 15 min after glucose administration were 2.5-3.0-fold higher than control levels. The transgene was also effective in ameliorating glucose intolerance of 70% depancreatized mice. These results indicate that VIP and PHM-27 produced from the transgenic beta cells efficiently enhance glucose-induced insulin secretion from beta cells by an autocrine mechanism. These results also suggest that genetic manipulation of islet beta cells by the human VIP/PHM-27 gene or delivery of VIP to beta cells may ultimately provide a valuable approach to enhancing insulin secretion in clinical diabetes.

Animals↗
PubMed1994

Different characteristics of hepatoid and non-hepatoid alpha-fetoprotein-producing gastric carcinomas: an experimental study using xenografted tumors.

The characteristics, including metastatic potential, of 5 xenografts of alpha-fetoprotein (AFP)-producing gastric carcinomas in nude mice, designated TSG1, TSG3, TSG11, TSG17 and TSG20, were examined. Of these xenografts, TSG1, TSG11 and TSG20 were regarded as hepatoid adenocarcinomas based on their morphological resemblance to hepatocellular carcinoma, frequent immunoreactivity for liver-cell markers, and excessive production of AFP with a high concanavalin A (Con-A)-binding property of hepatic type. On the other hand, TSG3 and TSG17 tumors showed the features of poorly differentiated medullary adenocarcinoma with scattered AFP-positive cells consistent with low AFP levels in mouse sera, and negative immunoreactivity for other liver-cell markers. Ultrastructurally, these tumors were composed of undifferentiated cells with a little adenocarcinomatous differentiation. Moreover, the AFP produced by TSG3 and TSG17 tumors had an extremely high Con-A nonbound fraction (80% to 90%), which was different from that of the hepatic or yolk-sac types. Therefore, both TSG3 and TSG17 tumors were regarded as non-hepatoid, poorly differentiated adenocarcinomas which could be differentiated from any types of AFP-producing gastric carcinoma. Furthermore, cells from hepatoid adenocarcinoma strains (TSG1, TSG11 and TSG20) injected into the spleens of nude mice produced liver metastases in all the mice examined, whereas cells from non-hepatoid carcinoma strains (TSG3 and TSG17) produced few or no liver metastases. Our data show that some non-hepatoid AFP-producing gastric carcinomas have lower liver-metastasizing potential than hepatoid AFP-producing gastric carcinomas.

Adenocarcinoma↗
PubMed1994

Patterns of lymphatic spread in thoracic esophageal cancer.

BACKGROUND: The cervical nodes have been excluded from the category of regional nodes in cases of thoracic esophageal cancer in the present TNM classifications. METHODS: One hundred and forty-one patients with thoracic esophageal cancer who had undergone extensive radical lymphadenectomy were included in the study. The patterns of early lymph node metastasis from the disease, in terms of lymph node metastases from the intramural tumors or those found in patients with a single metastatic node, were studied. Prognostic significance of the removal of the positive nodes also was examined in relation to the metastatic sites. RESULTS: Of the 47 patients with intramural cancer, only 21% had nodal metastases confined to the mediastinum, 11% had positive cervical nodes, and 23% had jumping metastases to the extramediastinal nodes. Of the 31 patients with a single metastatic node, 61% showed metastasis in a jumping fashion, and 19% had a positive node in the neck. Seventy-four (79.6%) of the 93 patients with vessel invasion also had lymph node metastases, whereas 20 (41.7%) of the 48 patients without vessel invasion had metastases to the lymph nodes (P < 0.001). The 5-year projected survival rate for patients with positive cervical nodes was 27%, with no significant difference in survival rate compared with that for patients with metastatic nodes in the mediastinum or the abdomen. The number of involved nodes was related significantly to outcome: The 5-year survival rates for the 45 patients with negative nodes the 66 patients with one to four positive nodes were 71.8 and 34.2%, respectively (P < 0.01), whereas none of the 27 patients with five or more positive nodes survived more than 3 years after the operation (P < 0.001). CONCLUSIONS: The cervical nodes should be included in the category of regional nodes in cases of thoracic esophageal cancer on the basis of the patterns of early lymph node metastases and the prognostic significance of a lymphadenectomy for metastases to these nodes.

Abdomen↗