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Biomedical subjects

H Hamada

Publications and source records attributed to H Hamada.

At least 415 records · Page 23Linked to original sources
PubMed1991

[A case of acute myocardial infarction due to coronary spasm].

The patient was a 47 year-old man, who has been known to have effort angina since September 1989. His exercise stress ECG has revealed ST elevation in V2-V4 with maximum exercise. He experienced severe chest pain lasting for an hour on the way to his office in the early morning on November 16, 1989, and was admitted to our hospital. His ECG and laboratory findings indicated typical acute anteroseptal myocardial infarction, but the coronary arteriography (CAG) which was performed 7 hours after the onset showed no significant stenotic lesion. After administrating nitrate and calcium antagonist, he has had no attack of angina pectoris and his exercise stress test has revealed no ST-T changes on his ECG. 1 month later, while antianginal drugs were discontinued in order to perform an ergonovine stress test, the patient frequently complained of left anterior chest pain with remarkable ST elevation in precordial leads on his ECG. The CAG at chronic stage revealed that there was a 99% stenosis at Segment 6 of the left anterior descending artery (LAD) which was supplied with good collateral flow from the right coronary artery. The LAD was completely occluded at Segment 6 after intracoronary administration of ergonovine maleate 0.005 mg to the left coronary artery. After the intracoronary infusion of isosorbide dinitrate, there was no significant stenosis seen in the LAD except the minimum wall irregularity at Segment 6. These findings suggested that coronary spasm might play a major role of the occurrence of acute myocardial infarction in this case.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium Channel Blockers↗
PubMed1991

[Study on the clinical usefulness of NCC-ST-439 in breast cancer].

We investigated the usefulness of NCC-ST-439, a new tumor marker in breast cancer. The positive rate of NCC-ST-439 in cases of primary breast cancer was 46.9%. In cases of primary breast cancer, there were no significant differences in average and positive rate among each group of patient age, tumor size, number of metastatic node, clinical stage and status of hormone receptor (ER, PgR). The positive rate of NCC-ST-439 in early breast cancer was as high as that in advanced case. NCC-ST-439 had better sensitivity than CEA and CA15-3, and decreased in serum level after the curative operation. We concluded that NCC-ST-439 is useful as a screening marker for the detection of early breast cancer and as a post operative monitoring marker for the surveillance of the recurrence.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1991

Esophagocutaneous fistula after anterior cervical spine surgery and successful treatment using a sternocleidomastoid muscle flap. A case report.

An esophagocutaneous fistula following anterior cervical fusion is rare. A 61-year-old man had cervical myelopathy because of ossification of the posterior longitudinal ligament of the cervical spine. Anterior decompression of the cervical spine and anterior fusion with strut bone grafting were performed. A second anterior fusion was done because the graft was dislodged after the patient fell out of bed one month after surgery. An esophagocutaneous fistula occurred three months after the second anterior surgery. One of the causes of this esophagocutaneous fistula was considered to be a pressure necrosis of the esophagus because of to projection of the bone graft. Conservative treatment, which consisted of wound drainage and intravenous administration of antibiotics, was tried but was unsuccessful. A good result was achieved by cancellous bone grafting, closure of the esophageal fistula, and transposition of a sternocleidomastoid muscle flap to the interspace between the esophagus and the cervical spine.

Cervical Vertebrae↗
PubMed1990

Detection of 300-kilodalton membrane protein in adriamycin-resistant human tumor cells by a monoclonal antibody MRK18.

To characterize the membrane changes related to adriamycin (ADM) resistance in tumor cells, we have developed monoclonal antibodies against an ADM-resistant subline of human myelogenous leukemia K562 (K562/ADM), and reported the overexpression of P-glycoprotein and 85-kDa protein as determined by the antibodies. In the present study, we have established a monoclonal antibody, MRK18, with higher reactivity to K562/ADM than to K562. MRK18 also showed higher reactivity to other human ADM-resistant lines, 2780AD and Hattori/ADM, than the corresponding parental lines. MRK18 also reacted to human breast cancer MCF-7 and human T-lymphoma CCRF-CEM which have never been exposed to anticancer agents in culture. MRK18 recognized a 300-kDa membrane protein of K562/ADM and MCF-7 and inhibited the growth of these cell lines in culture. These results indicate an induction of the 300-kDa protein during the development of ADM resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

Mouse-human chimeric antibody against the multidrug transporter P-glycoprotein.

In an effort to devise an effective treatment for human drug-resistant cancers, we have generated a monoclonal antibody, MRK16, reactive to the multidrug transporter P-glycoprotein. The monoclonal antibody inhibited the growth of human drug-resistant tumor cells in a xenograft model, suggesting its potential usefulness in the immunotherapy of drug-resistant cancers. In this study, we have developed a recombinant chimeric antibody in which the antigen-recognizing variable regions of MRK16 are joined with the constant regions of human antibodies. When human effector cells were used, the chimeric antibody, MH162, was more effective in killing drug-resistant tumor cells than the all-mouse monoclonal MRK16. The chimeric antibody against the multidrug transporter P-glycoprotein will be a useful agent in immunotherapy of human drug-resistant cancers.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

The concentration of tissue plasminogen activator and urokinase in plasma and tissues of patients with ovarian and uterine tumors.

The concentrations of tissue plasminogen activator (t-PA) and urokinase (UK) were measured in the plasma of patients with benign or malignant ovarian and uterine tumors. Plasma levels of t-PA were higher in patients with malignant ovarian and uterine tumors than in patients with benign tumors. Plasma UK levels were, however, not different between patients with ovarian and uterine tumors (benign or malignant) and normal persons. The concentrations of t-PA and UK of tissues of uterine myoma were lower than those in normal uterine muscular layer. UK levels of tissues of endometrial and cervical cancers were significantly higher than those in normal endometrium and uterine cervix, whereas t-PA levels were not different between these tumors compared with those in normal uterine tissues.

Female↗
PubMed1990

A novel octamer binding transcription factor is differentially expressed in mouse embryonic cells.

We have identified a novel octamer binding factor (Oct-3) in P19 embryonal carcinoma cells. Oct-3, which recognizes the typical octamer motif (ATTTGCAT) as well as the AT-rich sequence TTAAAATTCA, is present in P19 stem cells but disappears when the cells are induced to differentiate by retinoic acid (RA). Cloned cDNA corresponding to Oct-3 encodes a protein of 377 amino acids. Oct-3 has a conserved POU domain, but the remaining part is distinct from other POU domain-containing proteins such as Oct-1 and Oct-2. mRNA of 1.5 kb coding for Oct-3 is abundant in P19 stem cells but is dramatically repressed during RA-induced differentiation. Repression of the 1.5 kb mRNA is rapid and specific to RA. In mouse, oct-3 mRNA is undetectable in all the adult organs examined. The N-terminal proline-rich region of Oct-3, when fused to the DNA binding domain of c-Jun, functions as a transcriptional activating domain. We suggest that Oct-3 is a novel octamer binding transcription factor that is developmentally regulated during mouse embryogenesis.

Amino Acid Sequence↗
PubMed1990

Monoclonal anti-P-glycoprotein antibody-dependent killing of multidrug-resistant tumor cells by human mononuclear cells.

Mouse monoclonal antibodies (MRK16 and MRK17) against human multidrug-resistant cancer cell lines were tested for antibody-dependent cytotoxicity mediated by human blood mononuclear cells, using a 4-h 51Cr release assay. MRK16 (IgG2a isotype) was shown to be more effective than MRK17 (IgG1 isotype). Moreover, when four pairs of drug-resistant and their parent sensitive human cancer cells were tested for antibody-dependent cell-mediated cytolysis (ADCC) using MRK16, only the drug-resistant cell lines were susceptible to ADCC reaction. When highly purified lymphocytes (greater than 99%) and monocytes (greater than 97%) were isolated from blood mononuclear cells by centrifugal elutriation and adherence, MRK16 promoted both lymphocyte- and monocyte-mediated tumor cell killing, whereas MRK17 induced only a lymphocyte-mediated ADCC reaction. These results suggest that MRK16 of IgG2a subtype may be a useful therapeutic agent in eradication of drug-resistant cancer cells expressing P-glycoprotein through ADCC reaction.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

Specialized localization of P-glycoprotein recognized by MRK 16 monoclonal antibody in endothelial cells of the brain and the spinal cord.

This communication describes the cellular and ultrastructural localization in the central nervous system of P-glycoprotein (P-GP) recognized by a murine monoclonal antibody, MRK 16. At the ultrastructural level P-GP was strictly confined to the luminal surface of the endothelial cells which comprise the capillary vessels of the brain and the spinal cord. No P-GP was found in the endothelial cells of other organs. Our findings may be useful as a means to define the blood-brain barrier, and they imply that the blood-brain barrier is anatomically characterized by the presence of intercellular tight junctions between continuous nonfenestrated endothelial cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

Enhancement of the fibrinolytic activity in plasma by oral administration of nattokinase.

The existence of a potent fibrinolytic enzyme (nattokinase, NK) in the traditional fermented food called 'natto', was reported by us previously. It was confirmed that oral administration of NK (or natto) produced a mild and frequent enhancement of the fibrinolytic activity in the plasma, as indicated by the fibrinolytic parameters, and the production of tissue plasminogen activator. NK capsules were also administered orally to dogs with experimentally induced thrombosis, and lysis of the thrombi was observed by angiography. The results obtained suggest that NK represents a possible drug for use not only in the treatment of embolism but also in the prevention of the disease, since NK has a proven safety and can be massproduced.

Administration, Oral↗
PubMed1990

Growth dynamics of the heart from perinatal period to childhood.

In order to obtain information useful for the diagnosis of fetus and newborn heart disease, we established a theoretical model of perinatal cardiac growth. We measured with the use of ultrasonic cross-section imaging system the mitral valve ring dimension, tricuspid valve ring dimension, and total cardiac dimension as morphological parameters of the heart in 45 cases composed of fetuses and children. The obtained data were entered into a computer. With the use of these data, simulation was made on the basis of the general theory of biological development. The present simulation showed that from the fetal stage to childhood the growth rates of the foregoing three morphological parameters mutually differ, but during the period of growth to the age of 12 years of the present study, they all demonstrated continuous growth up to 3 1/2 years after birth when they reached a growth saturation level.

Aging↗
PubMed1990

Ovarian clear-cell carcinoma producing estradiol and human chorionic gonadotropin.

A case of clear-cell carcinoma of the ovary in a 52-year-old woman having an unusual menstrual history is presented. Serum concentrations of human chorionic gonadotropin (hCG) and estradiol were 120 mIU/ml and 86 pg/ml, respectively, while the serum FSH level was 43 mIU/ml. Immunohistochemistry of the tumor revealed positive staining for both hCG and estradiol in the tumor cells.

Adenocarcinoma↗
PubMed1990

[Study of a monoclonal antibody against new epithelial membrane antigens of transitional cell carcinoma].

Immunizing mice with a transitional cell cancer (TCC) tissue in the renal pelvis, we produced a monoclonal antibody (EH14) against new epithelial antigens. After the mice were immunized repeatedly, their splenic cells were harvested and fused with NS/1 myeloma cells. The normal kidney tissue of the same patient was used on Dot blots to select the hybridoma. A a result, one hybridoma whose antibody (EH14) reacted very strongly with TCC but only faintly with normal kidney tissue or normal bladder mucosa was obtained. On immunohistochemistry, EH14 stained all of the 29 TCC tissues. EH14 also stained uterus cancer (7/7) and gastric cancer (6/6) as well as the normal squamous cell and many types of the normal epithelium. All of the lymphnodes containing metastatic bladder cancer were strongly stained with EH14. EH14, however, did not stain interstitial tissues, muscles and sarcomas. The molecular weight of the antigen recognized by EH14 was 14KD and 28 KD on Western blot analysis, and the antigen was stable with formalin or ethanol. The antigen was not the same as that reported previously, and may be useful as a histological marker of TCC.

Animals↗
PubMed1990

[Immunological diagnosis of multidrug resistant cancer in urological malignancies].

A monoclonal antibody, MRK16, recognizing specifically an epitope of P-glycoprotein (P-GP) was used to determine the degree of expression of P-GP in kidney and urinary bladder cancers. Immunohistochemistry, immunoelectronmicroscopy, and immunoprecipitation were used for this study. Expression of P-GP was found in 6 of 20 kidney cancers treated without anticancer drugs. Also expression of P-GP was found in 17 of 47 urinary bladder cancers. 11 of 31 in primary cases, 0 of 5 in recurrent cases treated without anticancer drugs, and 6 of 11 in recurrent cases treated with anticancer drugs were positively expressed. These results indicate that a certain proportion of kidney and urinary bladder cancers intrinsically acquired multidrug resistance, and also that prior administration of anticancer drugs may induce P-GP in initially negative tumors. We also succeeded to detect MDR1 mRNA by means of in situ hybridization. From our present data, our methods to detect P-GP and MDR1 mRNA appeared to be very useful from the point of clinical application.

ATP Binding Cassette Transporter, Subfamily B, Mem↗