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H Morimoto

Publications and source records attributed to H Morimoto.

At least 181 records · Page 10Linked to original sources
PubMed1987

Use of sulfonated probes for in situ detection of amylase mRNA in formalin-fixed paraffin sections of human pancreas and submaxillary gland.

A sulfonated probe and its applicability to in situ hybridization is described and discussed. The DNA probes were modified by introducing an antigenic sulfone group into the cytidine residues of the denatured DNA (Budowsky EI, Sverdlov ED, Monastyrkaya GS: New method of selective and rapid modification of the cytidine residues. FEBS Lett 25:201, 1972). Hybridization of the sulfonated DNA with the target nucleic acid sequences was confirmed by an avidin-biotin peroxidase complex method using a monoclonal antibody specific to sulfonated DNA. The detection limit of this system was estimated to be about 1.25 pg of actual target sequences by dot blot hybridization analysis. When the sulfonated probes of human amylase cDNA were applied to in situ hybridization immunohistochemistry on formalin-fixed paraffin sections of the human pancreas and submaxillary gland, hybridization signals were clearly localized in the cytoplasm of the acinar cells of the pancreas, and in the serous cells of the submaxillary gland. Suitable probe lengths for in situ hybridization immunohistochemistry were between 100 and 800 bases. The in situ hybridization technique utilizing a sulfonated DNA probe is sensitive, simple, and easy to perform and applicable to studies of cell biology.

Amylases↗
PubMed1986

Oxygen equilibrium study and light absorption spectra of Ni(II)-Fe(II) hybrid hemoglobins.

Ni(II)-Fe(II) hybrid hemoglobins, in which hemes in either the alpha or beta subunit are substituted with Ni(II) protoporphyrin IX, have been prepared and characterized. Since Ni(II) protoporphyrin IX binds neither oxygen nor carbon monoxide, the oxygen equilibrium properties of the Fe subunit in these hybrid hemoglobins were specifically determined. K1 values, namely the equilibrium constants for the first oxygen molecule to bind to hemoglobin, agreed well for these hybrid hemoglobins with the K1 value of native hemoglobin A in various conditions. Therefore, Ni(II) protoporphyrin IX in these hybrid hemoglobins behaves like a permanently deoxygenated heme. Both Ne-Fe hybrid hemoglobins bound oxygen non-co-operatively at low pH values. When the pH was raised, alpha 2 (Fe) beta 2 (Ni) showed co-operativity, but the complementary hybrid, alpha 2 (Ni) beta 2 (Fe), did not show co-operativity even at pH 8.5. The light absorption spectra of Ni(II)-Fe(II) hybrid hemoglobins indicated that the coordination states of Ni(II) protoporphyrin IX in the alpha subunits responded to the structure of the hybrid, whereas those in the beta subunits were hardly changed. In a deoxy-like structure (the structure that looks like that observed in deoxyhemoglobin), four-co-ordinated Ni(II) protoporphyrin IX was dominant in the alpha (Ni) subunits, while under the conditions that stabilized an oxy-like structure (the structure that looks like that observed in oxyhemoglobin), five-co-ordinated Ni(II) protoporphyrin IX increased. The small change observed in the absorption spectrum of the beta (Ni) subunits is not related to the change of the co-ordination number of Ni(II) protoporphyrin IX. Non-co-operative binding of oxygen to the beta subunits in alpha 2 (Ni) beta 2 (Fe) accompanied the change of absorption spectrum in the alpha (Ni) subunits. We propose a possible interpretation of this unique feature.

Ferrous Compounds↗
PubMed1986

Properties of chemically modified Ni(II)-Fe(II) hybrid hemoglobins. Ni(II) protoporphyrin IX as a model for a permanent deoxy-heme.

Chemical modifications, NES-Cys(beta 93), des-Arg(alpha 141), and both modifications on the same molecule, were made to Ni-Fe hybrid hemoglobins, and their effect on individual subunits was investigated by measuring oxygen equilibrium curves, the Fe(II)-N epsilon (His F8) stretching Raman lines, and light-absorption spectra. The oxygen equilibrium properties indicated that modified Ni-Fe hybrid hemoglobins remain good models for the corresponding deoxy ferrous hemoglobins, although K1, the dissociation equilibrium constant for the first oxygen to bind to hemoglobin, was decreased by the chemical modifications. Resonance Raman spectra of deoxy alpha 2 (Fe) beta 2 (Ni) and light-absorption spectra of deoxy alpha 2 (Ni) beta 2 (Fe), revealed that the state of alpha hemes in both hybrid hemoglobins underwent a transition from a deoxy-like state to an oxy-like state caused by these chemical modifications when K1 was about 3 mm Hg (1 mm Hg approximately 133.3 Pa). On the other hand, the state of beta hemes in hybrid hemoglobins was little affected, when K1 was larger than 1 mm Hg. Modified alpha 2 (Fe) beta 2 (Ni) gave a Hill coefficient greater than unity with a maximum of 1.4 when K1 was about 4 mm Hg. The two-state model predicts that the K1 value at the maximum Hill coefficient should be much larger than this value. For oxygen binding to unmodified alpha 2 (Ni) beta 2 (Fe), oxygen equilibrium data suggested no structural change, while the spectral data showed a structural change around Ni(II) protoporphyrin IX in the alpha subunits. A similar situation was encountered with modified alpha 2 (Ni) beta 2 (Fe), although K1 was decreased as a result of the structural changes induced by the modifications.

Ferrous Compounds↗
PubMed1986

Actin filaments and tumorigenicity in a Fischer rat embryo fibroblast cell line (3Y1) transformed by ultraviolet-irradiated HSV.

The characteristics of the cytoskeleton of a Fischer rat embryo fibroblast cell line (3Y1) transformed by ultraviolet (UV)-irradiated HSV were studied by indirect immunofluorescence using anti-actin IgG. Parental 3Y1 cells possessed well-developed actin filaments, while 3Y1 cells transformed by UV-irradiated HSV also retained well-developed actin filaments. Transformed cells were divided into 2 groups according to tumorigenicity in newborn Fischer rats; one had a strongly tumorigenic potential and the other a weakly tumorigenic potential. Tumor-derived cell lines exhibited a highly tumorigenic potential, and were also divided into 2 groups, one with well-developed actin filaments and the other without well-developed actin filaments. Our results suggested that transformation or tumor formation by HSV is a multi-step process and that morphological loss of actin filaments in the cells is not essential to the tumorigenic potential of the cells transformed by HSV.

Actins↗
PubMed1986

Binding studies of [3H]lyngbyatoxin A and [3H]debromoaplysiatoxin to the phorbol ester receptor in a mouse epidermal particulate fraction.

The preparation of [3H]lyngbyatoxin A by catalytic triton-proton exchange of lyngbyatoxin A and [3H]debromoaplysiatoxin by tritiation-debromination of aplysiatoxin is described. The dose-response curves for the binding of [3H]lyngbyatoxin A and [3H]debromoaplysiatoxin to a mouse epidermal particulate fraction are virtually the same as the one previously described for [3H]12-O-tetradecanoylphorbol-13-acetate ([3H]TPA). The specific binding of [3H]TPA, [3H]-lyngbyatoxin A and [3H]debromoaplysiatoxin to the mouse epidermal particulate fraction is inhibited to the same degree by unlabeled TPA, teleocidin, lyngbyatoxin A, aplysiatoxin and debromoaplysiatoxin. This study indicates that TPA, lyngbyatoxin A and debromoaplysiatoxin bind to the same high affinity receptor in mouse skin.

Animals↗
PubMed1986

Characteristic regional prevalence of HTLV-I in Shimane Prefecture.

Serological survey for human T-lymphotropic virus type I (HTLV-I) was performed in Shimane Prefecture, Japan, located on the coast of Japan sea. The rates of anti-adult T-cell leukemia-associated antigen-positive sera were 4.2% and 6.9% respectively for males and females. The rate increased with age, particularly in females. From the geographical point of view, the Oki Islands and a very small focus in Shimane-cho had high rates of anti-adult T-cell leukemia-associated antigen positives. Even within the Oki Islands, there was a big difference in the rate of seropositives between Dozen and Dogo which are only 10 km apart. The focus, Shimane-cho, has a population of 299. Even within a small area, there is a tendency of HTLV-I carriers to form a very narrow focus.

Adolescent↗
PubMed1986

Stable integration of woodchuck hepatitis virus DNA in transplanted tumors and established tissue culture cells derived from a woodchuck primary hepatocellular carcinoma.

The fate of integrated woodchuck hepatitis viral (WHV) DNA was systematically investigated in DNA samples from primary hepatocellular carcinoma (HCC) of woodchucks, solid tumors transplanted in athymic mice derived from a primary HCC of woodchuck, and an established cell line of tissue culture originating from the transplanted tumor. In four of five woodchuck primary HCCs, WHV DNA integration was demonstrated in addition to various amounts of extrachromosomal replicative intermediate WHV DNA. The integration pattern of the primary HCCs does not indicate a common integration site on the host chromosome. The integration pattern in the established cells is identical to that in the transplanted tumor and similar but slightly different from that of the primary HCC. No extrachromosomal or replicative intermediates of WHV DNA were detected in the transplanted tumors or in the established cells of tissue culture. There are three integration sites on the chromosomes of the established cells. Results of Southern hybridization and restriction maps of cloned fragments suggest that all of these integrated WHV DNA sequences are not a complete genome but a part of the genome. A small portion corresponding to the cohesive region of the genome was not detected in all of these integrated WHV DNA. A positive role of WHV DNA integration on the generation of HCC is strongly suggested by the high incidence of WHV DNA integration in woodchuck primary HCCs and the stable maintenance of a certain mode of WHV DNA integration in the hepatoma-derived cell populations during passages of transplantation or serial growth of tissue culture.

Animals↗
PubMed1986

[A resected case of collision tumor of hepatocellular carcinoma and primary liver rhabdomyosarcoma].

Primary liver sarcoma is rare and especially its coexistence with hepatocellular carcinoma is extremely rare. We have collected eight cases of their coexistence in the literatures. The patient was a 62-year-old male complaining of right hypochondralgia and general malaise for about one month. CT scanning revealed the liver tumor and right hepatic lobectomy was performed. The tumor was sized in 14 by 9 by 9 cm and composed of hepatocellular carcinoma and rhabdomyosarcoma, which were were collided. Apparent striations in the rhabdomyosarcoma cells was observed under light-microscope. Alphafetoprotein, of which serum level was extraordinarily high, was detected only in hepatocellular carcinoma by special stains. He discharged one month after operation. He was readmitted due to recurrence and received trans-arterial embolisation therapy and systemic chemotherapy. Though transient effect was obtained. He died forty-five days after operation. Autopsy revealed that recurrent liver tumors consisted of only hepatocellular carcinoma and that no other tumorous lesion was found in the other parts of the body. Rhabdomyosarcoma was proved to be primary tumor the liver.

Carcinoma, Hepatocellular↗
PubMed1986

[Results of in vitro chemosensitivity assays: human tumor clonogenic and scintillation assay].

The authors reviewed their experiences to date with chemosensitivity testing of 629 tumors by human tumor clonogenic assay (HTCA) and of 199 tumors by scintillation assay (SA). HTCA and SA were both performed using a double-layer-soft-agar system with continuous exposure of cells to one concentration of standard anticancer drugs. Overall, 60% of specimens in HTCA and 58% in SA produced significant growth in vitro. HTCA was 52% (13/25) reliable for predicting in vivo sensitivity, and 95% (36/38) reliable for in vivo resistance, whereas SA was 40% (8/20) reliable for in vivo sensitivity and 88% (21/24) for in vivo resistance. The current results indicate that there is no particular difference in the success rate and in the predictive accuracy for in vivo sensitivity and resistance between HTCA and SA. Therefore, it is doubtful whether only clonogenic tumor cells among whole tumor cell populations should be selected in assessing the chemosensitivities of human tumors. In vitro success rates were variable, depending on the tumor histology. In vitro growth of gastric cancer specimens was characteristically lower than that of colon cancer specimens (48% and 60% in HTCA, and 46% and 68% in SA, respectively). (p less than 0.005). Optimal in vitro-in vivo drug concentrations and culture conditions are still being defined. Correlation studies of in vitro-in vivo responses of gastrointestinal cancers suggested that in vitro concentrations of 5-fluorouracil and mitomycin C used in this study were considerably higher than their optimal doses. Tumor cell heterogeneity poses significant problems in the clinical use of chemosensitivity assays. The question arises as to whether a single biopsy specimen is representative of a patient's disease. In this last study, we sought evidence of tumor heterogeneity by comparing chemosensitivity responses between: 1) different portions of a single tumor, 2) a primary and a metastatic biopsy taken from a patient on the same day, and 3) different metastases from a patient taken on the same day. The results demonstrated the presence of considerable heterogeneity of response to chemotherapy among different tumors from the same patient, and even within the same tumor. The reported discrepancies of in vitro and in vivo sensitivity may be due to such therapeutic heterogeneity among tumors.

Antineoplastic Agents↗
PubMed1985

Studies on the effects of various types of surgery on electrical and contractile activities of the canine stomach.

In order to clarify the gastric electrical and contractile activity after various types of surgery, 32 mongrel dogs equipped with bipolar electrodes on the anterior wall of the stomach underwent various types of operations. The basic electric rhythm (BER) frequency after middle segmental gastrectomy (MSG) with SPV was markedly reduced, but gradually returned to show synchronization with that of the preoperative value. The propagation velocity of the BER decreased. Dysrhythmias were observed to occur in high incidence in the early postoperative period, but were transient occurrences. High-frequency-dysrhythmias were observed in cases of MSG with pyloroplasty (PP). PP increased the frequency of dysrhythmias probably due to deranging the electric insulator of the pyloric ring. In cases of upper segmental gastrectomy, the BER frequency didn't synchronize with that of the preoperative state even in the late postoperative period. The gastric motility after MSG with SPV recovered in the late postoperative period, so the pyloric ring could be preserved. After massive distal small bowel resection, propagation velocity of the BER of the stomach were markedly decreased. Of the 5 gut hormones examined, only CCK correlated with the propagation velocity of the BER.

Animals↗