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Biomedical subjects

M Ueda

Publications and source records attributed to M Ueda.

At least 1,081 records · Page 60Linked to original sources
PubMed1989

Prognostic significance of epidermal growth factor receptor in esophageal squamous cell carcinomas.

The prognostic value of epidermal growth factor (EGF) receptor level was studied in 32 patients with esophageal squamous cell carcinoma. The EGF receptor levels of tumors were measured by iodine 125 (125I)-EGF binding assay, and the patients subsequently were divided into two groups: a group with high EGF binding capacities (greater than or equal to 2.5% of input), and a group with low EGF binding capacities (less than 2.5% of input). The cumulative survival rates for the two groups were calculated by the Kaplan-Meier method. The generalized Wilcoxon test indicated that the survival rate of the high EGF binding group was significantly lower than that of the low EGF binding group (P less than 0.05). In tumors from two patients with the highest EGF receptor levels, EGF receptor gene amplification was observed. These patients developed mediastinal lymph node metastasis and died 4 and 11 months after surgery, respectively. These results suggest that elevated EGF receptor level is a significant prognostic indicator for esophageal squamous cell carcinoma.

Aged↗
PubMed1989

Solubilization and characterization of erythropoietin receptor from transplantable mouse erythroblastic leukemic cells.

Functional erythropoietin (Ep) receptor (Ep-R) on transplantable mouse leukemic cells was solubilized by 3[(3-cholamidopropyl)dimethyl ammonio]-1-propanesulfate (CHAPS). An assay of the solubilized Ep-R was established: (1) radioiodinated Ep was bound to the solubilized Ep-R, (2) Ep.Ep-R complexes were covalently cross-linked, (3) the cross-linked products were selectively precipitated by polyethylene glycol, (4) the products were separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and (5) the Ep.Ep-R cross-linked products were measured. Optimal conditions to yield the cross-linked products and to stabilize the solubilized Ep-R were found. The solubilized Ep-R had properties similar to those of Ep-R on the membrane with respect to binding with Ep and the cross-linked products. These results would be exploited to allow purification of Ep-R.

Animals↗
PubMed1989

A dicarba analog of beta-atrial natriuretic peptide (beta-ANP) inhibits guanosine 3',5'-cyclic monophosphate production induced by alpha-ANP in cultured rat vascular smooth muscle cells.

The synthesis and biological properties are described of [Asu7,23']-beta-ANP-(7-28) (Asu, L-alpha-aminosuberic acid), a dicarba analog of beta-atrial natriuretic peptide (beta-ANP, an antiparallel dimer of human alpha-ANP with the chains linked by 7-23' and 7'-23 disulfide bonds). This Asu-analog (referred to as analog III) displaced 125I-alpha-ANP specifically bound to cultured rat vascular smooth muscle cells (VSMC) with an apparent Ki of 2.1 x 10(-8) M, but did not stimulate formation of intracellular cGMP at 10(-8) -10(-5) M. Analog III inhibited the alpha-ANP-stimulated cGMP production in VSMC competitively with a pA2 value of 7.45 and behaved as an antagonist of alpha-ANP in rat aorta smooth muscle relaxation. In addition, beta-ANP was also shown to inhibit the alpha-ANP-induced cGMP production in a dose-dependent manner. The mechanism of action of beta-ANP is also discussed.

Animals↗
PubMed1989

Comparison of vascular and platelet thromboxane A2/prostaglandin H2 receptors in the pig.

We compared the properties of vascular and platelet thromboxane A2/prostaglandin H2 receptors in the pig. The binding profiles of U46619, several prostaglandins and thromboxane A2/prostaglandin H2 receptor antagonists to the aorta and platelet receptors were almost the same irrespective of whether the agonist ([3H]U46619) or the antagonist ([3H]SQ29,548) radioligand was used, except that the receptor density in the latter was 4 times higher than that in the aorta. The antagonists suppressed U46619-induced contraction of pig coronary artery and secondary aggregation of platelets at potencies comparable to their KI values in the binding experiments. On the other hand, the responses of the artery specimens to U46619 and the prostaglandins differed from those of the platelets. Thus, the binding sites in the vascular and platelet receptors seem to be the same or quite similar, but there seem to be different mechanism(s) leading the agonistic binding signal to final responses.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1989

Selective killing of squamous carcinoma cells by an immunotoxin that recognizes the EGF receptor.

We have conjugated a murine monoclonal antibody (B4G7) against the human epidermal growth factor (EGF) receptor to gelonin, a 60S ribosome inactivating protein, via N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP) and 2-iminothiolane. The B4G7-gelonin conjugate bound to the cell surface in proportion to the number of EGF receptors and competed with B4G7 antibody for binding to EGF receptors. The conjugate killed EGF receptor-hyperproducing squamous carcinoma cells (A431, NA, Ca9-22, TE5), and to some extent, human fibroblasts (HFO). It did not kill EGF receptor-deficient small-cell lung cancer cells (H69) and mouse fibroblasts (Swiss/3T3). Free B4G7, gelonin or a mixture of B4G7 and gelonin did not kill A431 cells. The number of EGF receptors was correlated to cytotoxicity at 10(-8) M of the conjugate, and the data were fitted to the regression equation: y = -35.83 log x +233.4 (correlation coefficient = -0.9995). These results suggest that the B4G7-gelonin conjugate may be a useful weapon for targeting therapy to squamous-cell carcinomas.

Animals↗
PubMed1989

Expression of epidermal growth factor receptors in four histologic cell types of lung cancer.

Lung cancer tissues from 68 patients were examined for epidermal growth factor (EGF) receptor levels and EGF receptor gene copy numbers. Histologic cell types of these lung cancer tissues included squamous-cell carcinoma (n = 30), adenocarcinoma (n = 28), large-cell carcinoma (n = 4), and small-cell carcinoma (n = 6). Tissues of squamous-cell carcinoma exhibited exceptionally high 125I-EGF binding activity, and those of small-cell carcinoma showed no EGF binding activity. Southern blot hybridization analysis revealed EGF receptor gene amplification in the squamous-cell carcinomas with high EGF binding activity. The EGF receptor levels in squamous-cell carcinomas and adenocarcinomas were compared with their pathological staging grouping and pathological findings, including degree of differentiation, diameter of tumor, and lymph node metastasis. However, unlike previous reports on breast and bladder cancers, there was no obvious correlation between these pathological characteristics and the EGF receptor levels of lung cancer.

Adenocarcinoma↗
PubMed1989

Expression and characterization of erythropoietin receptors on normal human bone marrow cells.

We studied the specific binding of 125I-labeled bioactive recombinant human erythropoietin (Epo) to human bone marrow mononuclear cells (BMNC) obtained from normal subjects. The 125I-labeled Epo bound specifically to the BMNC. Scatchard analysis of the data showed two classes of binding sites; one high affinity (Kd 0.07 nM) and the other low affinity (Kd 0.38 nM). The number of Epo binding sites per BMNC was 46 +/- 16 high-affinity receptors and 91 +/- 51 low-affinity receptors. The specific binding was displaced by unlabeled Epo, but not by other growth factors. Receptor internalization was observed significantly at 37 degrees C, but was prevented by the presence of 0.2% sodium azide. These findings indicate that human BMNC possess two classes of specific Epo receptors with characteristics of a hormone-receptor association.

Binding, Competitive↗
PubMed1989

The calpain-calpastatin system in hematopoietic cells.

Calpain I requires low Ca2+ for activation and calpain II requires high Ca2+. It was generally accepted that erythrocytes contain calpain I and calpastatin, but no calpain II. We have recently found, however, that nucleated chicken erythrocytes contain both calpains I and II in addition to calpastatin. The finding is significant in rectifying the previous view that the chicken has only one molecular species of calpain, whereas mammals have two. Another erroneous view which prevailed previously was that polymorphonuclear (PMN) cells contain only one calpain species. We could also recently demonstrate that pig PMN cells do contain both calpains I and II. The cloning of cDNAs for calpastatin enabled us to utilize them as the probes in studying the expression of calpastatin in various hematopoietic cell-line cells. We found that several T cells infected with human retrovirus HTLV-I markedly increased the production of calpastatin, which could be measured both by calpain-inhibition assay and by Western blot analysis, but the level of mRNA for calpastatin did not significantly change when compared with noninfected T cells. The increase in calpastatin protein always parallels with the expression of interleukin 2 receptor protein by the HTLV-I-infected T cells, although the biological implication of such phenomena is almost entirely unknown yet.

Animals↗
PubMed1989

Pancreatic-type hyperamylasemia in end-stage renal disease.

Pancreatic-type isoamylase (P-type) and salivary-type isoamylase (S-type) activities were determined by the wheat protein inhibitor method in 29 patients with end-stage renal disease and in 38 healthy volunteers. Serum levels of total amylase (322 +/- 43 units/liter) and P-type (212 +/- 39 units/liter) in ESRD were significantly higher than those of controls (total: 142 +/- 7 units/liter, P less than 0.01; P-type: 52 +/- 4 units/liter, P less than 0.01). There was no significant difference between S-type activities in ESRD (110 +/- 16 units/liter) and in controls (90 +/- 6 units/liter). The ratios of amylase clearance to creatinine clearance (Cam/Ccr) and S-type clearance to creatinine clearance (Cs-amy/Ccr) rose significantly in ESRD(Cam/Ccr: 5.7 +/- 0.6%; Cs-amy/Ccr: 4.3 +/- 0.55%) compared to controls (Cam/Ccr: 3.2 +/- 0.24%, P less than 0.01; Cs-amy/Ccr: 2.1 +/- 0.17%, P less than 0.01). The ratio of P-type clearance to creatinine clearance (Cp-amy/Ccr) revealed no significant difference between ESRD (5.5 +/- 0.54%) and controls (5.6 +/- 0.42%). The renal excretion of P-type appeared to be more impaired than that of S-type in ESRD.

Adult↗
PubMed1989

Isolation and characterization of monoclonal antibodies to human parainfluenza virus type 4 and their use in revealing antigenic relation between subtypes 4A and 4B.

Eighty monoclonal antibodies (MAbs) against parainfluenza virus type 4(PIV-4) were isolated and characterized. Of 50 MAbs against PIV-4A, 14 reacted with the nucleocapsid (NP) protein, 11 with the hemagglutinin-neuraminidase (HN) glycoprotein, 6 with the fusion (F) glycoprotein, and 19 with the matrix (M) protein. With the aid of the PIV-4A and PIV-2 specific MAbs showing cross-reactivity with PIV-4B, the structural proteins of PIV-4B were identified. gp72, p65, gp65, gp55, p53, and p40 of PIV-4B were assigned to HN, NP, Fo, F1, P, and M proteins, respectively. Based on the results, specificities of the MAbs against PIV-4B were determined. Of 30 hybridoma clones against PIV-4B, 13 clones were found to produce antibodies against the NP protein, 7 against the HN protein, and 10 against the F protein. Epitope mapping of these MAbs was performed with competitive binding assays in ELISA. According to their biological activities, the MAbs against the HN protein of either PIV-4A or 4B could be divided into three groups. The first group showed high hemagglutination inhibition (HI), hemolysis inhibition (HLI), and neutralizing (NT) activities. The second group showed high NT activity, but could not block hemagglutination. The final group showed a lower level of all activities. The MAbs against the F protein of PIV-4A and against PIV-4B were divided into two groups. Some MAbs against the F protein had high titer of NT, suggesting that the F protein had neutralizing-related epitopes. Antigenicity of the NP protein was highly conserved among subtypes of PIV-4. On the other hand, the MAbs against the HN and the F proteins showed high reactivity with the homologous subtype viruses, but low reactivity with the heterologous subtype viruses, indicating that the external glycoproteins exhibited antigenic variations between two subtypes of PIV-4. When the immunological interrelationship among various paramyxoviruses was analyzed. PIV-4 was found to be antigenically related to PIV-2, SV 5, and mumps virus.

Animals↗
PubMed1989

Dihydropyrimidines: novel calcium antagonists with potent and long-lasting vasodilative and antihypertensive activity.

The novel calcium antagonists 3-N-substituted-3,4-dihydropyrimidines 1 and 9 and 3-N-substituted-dihydro-pyrimidin-2(1H)-ones 8 were regioselectively synthesized in good yields. Compounds 1 [especially 1s [R1 = (CH2)2N(benzyl)(2-naphthylmethyl), R2 = i-Pr, X = 0-NO2] and 1t [R1 = (CH2)2N(benzyl)(3,4-dichlorobenzyl), R2 = i-Pr, X = 0-NO2]] exhibited not only more potent and longer lasting vasodilative action but also a hypotensive activity with slow onset as compared with dihydropyridines. Moreover, some dihydropyrimidines [1q [R1 = (CH2)2N(benzyl)(3-phenylpropyl), R2 = CH2(cyclopropyl), X = 0-NO2], 1s, and 1t] were weaker in blocking atrioventricular conduction in anesthetized open-chest dogs and less toxic than the dihydropyridines.

Animals↗
PubMed1989

Peroxisomal acetoacetyl-CoA thiolase and 3-ketoacyl-CoA thiolase from an n-alkane-utilizing yeast, Candida tropicalis: purification and characterization.

Acetoacetyl-CoA thiolase (Thiolase I) and 3-ketoacyl-CoA thiolase (Thiolase III) found in peroxisomes of an n-alkane-utilizing yeast, Candida tropicalis pK 233, were each purified to homogeneity by successive column chromatographies. Thiolase I was composed of six identical subunits whose molecular masses were 41,000 Da, and Thiolase III was a homodimer composed of 43,000 Da subunits. The results of limited proteolysis of the respective thiolases indicated that they were quite different in peptide components. Furthermore, these enzymes were immunochemically distinguishable. The kinetic studies showed that the substrates with long chains were degraded exclusively by Thiolase III, while acetoacetyl-CoA was degraded preferentially by Thiolase I. Thus, in the yeast, the complete degradation of fatty acids is suggested to be carried out efficiently in peroxisomes.

Acetyl-CoA C-Acetyltransferase↗
PubMed1989

Actions of a novel thromboxane A2-receptor antagonist, S-145, on isolated monkey and cat arteries.

The effects of a novel thromboxane (Tx) A2-receptor antagonist, S-145, were investigated mainly in helical strips of monkey and cat arteries. S-145 (3 x 10(-10) to 3 x 10(-9) M) attenuated the contraction induced by U46619 (2 x 10(-10) to 10(-7) M), which produced concentration-dependent contraction in monkey cerebral, coronary, and mesenteric arteries, and cat cerebral arteries. The attenuation in the different monkey arteries did not differ much, and it tended to be greater in cat cerebral arteries than in monkey at concentrations of less than 10(-9) M S-145. S-145 also suppressed contractions in cat cerebral arteries induced by prostaglandin (PG) F2 alpha, PGE2, and PGD2. However, S-145 did not affect the contractile responses to PGF2 alpha in cat iris sphincter muscle and to PGE2 in guinea pig ileum. In cat mesenteric arteries, S-145 did not affect contractions induced by norepinephrine or K+, or relaxations induced by PGI2 or adenosine. The addition of S-145 (10(-9)-10(-8) M) produced a transient contraction in cat cerebral arteries, and when S-145 (3 x 10(-11) to 3 x 10(-7) M) was cumulatively added, the contraction was not produced. The measurement of antagonistic potency of S-145 was not complicated by its agonistic effect, since the former potency was always determined after confirming absence of the latter effect. These results suggest that S-145 is a potent TxA2-receptor antagonist with partial agonistic activity in vascular smooth muscle. PGF2 alpha, PGE2, and PGD2, however, at least in part, seemed to interact with the TxA2 receptor in vascular smooth muscle.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1989

Immunological response of monkeys infected intranasally with human parainfluenza virus type 4.

This report describes our attempt to establish an experimental animal model for human parainfluenza virus type 4A (HPIV-4A) and 4B (HPIV-4B) infection, which was used to study the immune response to the viruses. Monkeys were inoculated intranasally with the viruses, and at 10 weeks post-infection they were re-infected with homologous subtype viruses. Virus-specific IgM and IgG serum antibodies were measured by ELISA. A small peak of IgM antibody was detected in the monkeys re-infected with HPIV-4B, whereas this response was not detected after re-infection with HPIV-4A. Virus-specific IgA and IgE antibodies were not detected in sera following infection and re-infection with HPIV-4. However virus-specific IgA and IgE antibodies were found in the saliva and nasal exudates of monkeys infected with either HPIV-4A or -4B. Re-infection of monkeys with HPIV-4B also stimulated an IgA and IgE response. To our knowledge this is the first description of an experimental animal. The kinetics of haemagglutinin-inhibition and neutralization (NT) antibodies were similar to that of virus-specific IgG antibodies. The NT titres of sera from HPIV-4A-infected monkeys were enhanced by the addition of complement, whereas complement did not affect the NT activity of sera obtained from HPIV-4B-infected animals. Antigenic specificities of IgG antibody induced by HPIV-4 infection were analysed with radioimmunoprecipitation followed by SDS-PAGE. Anti-NP, -HN and -F antibodies appeared 2 weeks after infection, and the highest titres were found 2 weeks after re-infection. Anti-F antibody production followed a biphasic pattern previously observed in mumps virus infection.

Animals↗
PubMed1989

Treatment of malignant melanoma by selective thermal neutron capture therapy using melanoma-seeking compound.

As pigment cells undergo melanoma genesis, accentuated melanogenesis concurrently occurs in principle. Subsequent to the understanding of intrinsic factors controlling both processes, we found our selective melanoma neutron capture therapy (NCT) using 10B-dopa (melanin substrate) analogue, 10B1-p-boronophenylalanine (10B1-BPA), followed by 10B(n, alpha)7Li reaction, induced by essentially harmless thermal neutrons, which releases energy of 2.33 MeV to 14 mu, the diameter of melanoma cells. In vitro/in vivo radiobiological analysis revealed the highly enhanced melanoma killing effect of 10B1-BPA. Chemical and prompt gamma ray spectrometry assays of 10B accumulated within melanoma cells after 10B1-BPA administration in vitro and in vivo show high affinity, e.g., 10B melanoma/blood ratio of 11.5. After successfully eradicating melanoma transplanted into hamsters with NCT, we advanced to preclinical studies using spontaneously occurring melanoma in Duroc pig skin. We cured three melanoma cases, 4.6 to 12 cm in diameter, by single neutron capture treatment. Complete disappearance of melanoma was obtained without substantial side effects. Acute and subacute toxicity as well as pharmacodynamics of 10B1-BPA have been studied in relation to therapeutic dosage requirements. Clinical radiation dosimetry using human phantom has been carried out. Further preclinical studies using human melanoma transplanted into nude mouse have been a useful model for obtaining optimal results for each melanoma type. We recently treated the first human melanoma patient with our NCT, using essentially the method for Duroc pig melanoma, and obtained similar regression time course leading to cure.

Animals↗
PubMed1989

Assessment of cardiopulmonary baroreflex function in hypertensive and normotensive subjects with or without hypertensive relatives.

1. To investigate whether cardiopulmonary baroreflex control contributes to the pathogenesis and progression of hypertension, we have evaluated the function of the cardiopulmonary baroreflex in 22 patients with essential hypertension and in 17 volunteers with normotension. The normotensive group consisted of 8 subjects with a family history of hypertension and nine with no family history. 2. Forearm vascular resistance (FVR) and central venous pressure (CVP) were measured under control conditions when -10 mmHg lower body negative pressure was applied; the cardiopulmonary slope (CPS = delta FVR/delta CVP) was calculated as an index of the cardiopulmonary baroreflex function. 3. CPS was significantly higher in hypertensives (6.0 +/- 3.93 [s.d.], P less than 0.01) and also tended to be higher in normotensives with a family history of hypertension (3.9 +/- 3.53, P less than 0.05), compared with normotensives without a family history of hypertension (1.7 +/- 0.88). 4. When the hypertensives were divided into two groups, depending on whether CPS was greater or less than 6.0 units, cardiac wall thickness (20 +/- 1.6 mm vs 23 +/- 3.2 mm, P less than 0.05) and the renal vascular resistance (20.9 +/- 6.52 units vs 28.9 +/- 7.32 units, P less than 0.05) were both significantly higher in the Low CPS group. 5. These findings suggest that cardiopulmonary baroreflex function was augmented even in normotensive subjects with hypertensive relatives, as compared with those without hypertensive subjects. Furthermore, cardiopulmonary baroreflex function was augmented in the early stages of hypertension and diminished further with increasing severity.

Adult↗
PubMed1989

An autopsy case of cholesterol embolism following percutaneous transluminal coronary angioplasty and aortography.

A 67-year-old woman with a 6-year history of angina pectoris underwent percutaneous transluminal coronary angioplasty. Just after manipulation of the guiding catheter during a second attempt at angioplasty and aortography, the patient developed intestinal obstruction with peritonitis. Laparotomy was performed, and surgical specimens taken during surgery revealed necrosis and perforation of the small intestine. Microscopical examination proved that this was the result of multiple fresh cholesterol emboli in the arteries. Postoperatively, renal failure and sepsis developed, and the patient died 13 days after surgery. Autopsy revealed multiple cholesterol emboli in arteries of the intestine, spleen, pancreas, liver and kidneys. This case demonstrates that cholesterol embolism can be a serious complication of percutaneous transluminal coronary angioplasty.

Aged↗