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Biomedical subjects

G Tamura

Publications and source records attributed to G Tamura.

At least 181 records · Page 10Linked to original sources

Molecular cloning of the glucoamylase gene of Aspergillus shirousami and its expression in Aspergillus oryzae.

The glucoamylase enzyme (GAase) gene from Aspergillus shirousami was cloned and sequenced from genomic and cDNA libraries. The genomic gene was located in the 5.4 kb EcoRI fragment. The deduced amino acid sequence of GAase contained 639 amino acid residues with a relative molecular mass of approximately 68,000 daltons (non-glycosylated form). The genomic gene of A. shirousami GAase was introduced into Aspergillus oryzae. These transformants had increased GAase and raw starch degradation (RSD) activity in culture media and in rice-koji extracts. Analysis by Southern, Northern, SDS-PAGE, and Western blot techniques confirmed the foreign gene was correctly transcribed, translated, and expressed in A. oryzae.

Amino Acid Sequence↗

Eosinophil and neutrophil production of leukotriene C4 and B4: comparison of cells from asthmatic subjects and healthy donors.

Production of LTC4 and LTB4 by eosinophils and neutrophils was compared between nine asymptomatic asthmatic subjects and eight healthy donors. We observed a statistically significant difference in LTC4 generated by eosinophils, but not LTB4 produced by neutrophils. These findings suggest a quantitative difference in eosinophils between asthmatic subjects and healthy donors.

Asthma↗

Karyometric and DNA content analyses of cancer cells in stage III breast cancer with reference to prognosis.

Karyometric and DNA content analyses were simultaneously performed on 32 cases of stage III invasive ductal breast cancer using an image analysis system. From the karyometric analysis, the nuclear areas (NAs; microns 2) were (mean +/- SD) 36.27 +/- 9.40 in five-year survivors (n 17) and 57.14 +/- 13.26 in non-survivors (n 15). The nuclear shape factors (NSFs; NSF = 4 pi X NA/NP2; NP, nuclear perimeter) were 0.756 +/- 0.037 in survivors and 0.716 +/- 0.040 in non-survivors. The NA was significantly larger (P less than 0.01) and the NSF significantly lower (P less than 0.01) in non-survivors than in survivors. From the DNA content analysis, the DNA content values (c; see Measurements section) were +/- 2.59 +/- 0.70 in survivors and 3.72 +/- 1.08 in non-survivors. The percentages of aneuploid cells over 4c were 7.10 +/- 9.89 in survivors and 23.07 +/- 20.19 in non-survivors. The DNA content and the percentage of aneuploid cells over 4c were significantly higher (P less than 0.01) in non-survivors than in survivors. This method may be valuable for estimating the prognosis of patients with invasive ductal carcinoma of the breast.

Adult↗

[A histological evaluation of the therapeutic effects and the clinical findings in prostatic carcinomas].

A histological evaluation of the effects of therapy has been conducted on 22 prostatic carcinoma cases, according to the criterion proposed by the committee to establish the general rule for clinical and pathological studies judging the effects of therapy in cases of prostatic cancer. Studied in particular was the relation between the histological effects of therapy and the clinical course. Marked therapeutic effects were observed in cases of low grade tumors. Further, the patients' prognosis tended to be affected by the histological grade rather than by the histological effect of the treatment. The course of the serum total acid phosphatase levels tended to correlate with the histological effect of the treatment.

Acid Phosphatase↗

Secretory carcinoma coexistent with mucinous carcinoma in the breast. Report of a case.

Secretory carcinoma and mucinous carcinoma were found to coexist in the breast of a 67-year-old post-menopausal woman, although the tumors were separated by a thin fibrous septum. Histochemically, intra- and extracellular secretory materials in both carcinomas were strongly positive for alcian blue, PAS and mucicarmine staining, but immunohistochemically negative for alpha-lactalbumin and CEA. Membrane-bound intracytoplasmic vacuoles showing emiocytosis were observed in both the secretory and mucinous carcinomas by electron microscopy. No differences were observed between the tumor cells of secretory carcinoma and those of mucinous carcinoma by histochemistry, immunohistochemistry and electron microscopy. However, there were definite statistically significant differences in the results of morphometry of tumor cell nuclei. Secretory carcinoma is considered to be an anaplastic variant type of mucinous carcinoma.

Adenocarcinoma, Mucinous↗

Pharmacological effect of KC-404 on leukotriene release from human leukocytes induced by ionophore A23187.

Release of leukotriene (LT) B4, LTC4 and histamine from human peripheral mixed leukocytes stimulated with calcium ionophore A23187 was evaluated. The amounts of LTB4 and LTC4 in supernatants were analyzed by high performance liquid chromatography and histamine was measured by an automated fluorometric technique. A time-course study demonstrated the characteristic patterns of the release of these mediators. LTB4 and LTC4 were more slowly released than histamine and the release of these LTs was inhibited by KC-404, a novel anti-asthmatic drug which has no effect on histamine release.

Calcimycin↗

A production of Dermatophagoides farinae allergen-specific IgE and Ig(G + M) antibodies by cultured peripheral blood mononuclear cells of patients with extrinsic bronchial asthma.

Using a modified reverse hemolytic plaque assay, we measured in vitro production of Dermatophagoides farinae allergen-specific IgE and Ig(G + M) antibodies by peripheral blood mononuclear cells in 19 patients with extrinsic bronchial asthma. Circulating the allergen-specific IgE was estimated by means of the Phadebas radioallergosorbent test system. We found a significant difference in the production of the allergen-specific IgE antibody by the cells between asthmatic patients with positive and negative circulating the allergen-specific IgE.

Adolescent↗

Neurokinin A-induced bronchial hyperresponsiveness to methacholine in Japanese monkeys.

The present study was designed to investigate whether neurokinin A (NKA) and substance P (SP) increase bronchial responsiveness to methacholine (MCh). Before and 1, 2, 3 and 4 weeks after three Japanese monkeys had inhaled 10(-8) M NKA and 10(-8) M SP for 2 min, bronchial responsiveness to inhaled MCh was evaluated. Pulmonary flow resistance (R1) and dynamic lung compliance (Cdyn) were used as pulmonary function tests. Dose-response curves of R1 to inhaled MCh were shifted to the left 1 to 4 weeks after NKA treatment, compared with that obtained before treatment. However, SP treatment did not change the R1 dose-response curve. Thus, bronchial responsiveness to MCh was increased by inhalation of 10(-8) M NKA in Japanese monkeys.

Airway Resistance↗

[Relationship between bronchial asthma and mite].

We studied the relationship between bronchial asthma and mite as an antigen by reviewing previous reports. The incidence of the bronchial asthma has been increasing and it is estimated to be more than 2% of the total population. The main components of the antigen in the house dust (H, D.), which has been considered to be an important antigen of the perennial asthma, are Dermatophagoides farinae (D, f.) and Dermatophagoides pteronyssinus (D, p.) in H, D. The housing environment in recent years have become favorable for the reproduction of D, f. and D, p. It is considered that environmental pollution increases the incidence of asthma, especially infants.

Adolescent↗

Specificity of alkaline elastase Bacillus on the oxidized insulin A- and B-chains.

The substrate specificity of alkaline elastase Bacillus from alkalophilic Bacillus sp. Ya-B was investigated using oxidized insulin A- and B-chains. Under time-limited cleavage, the initial cleavage site of the enzyme on the oxidized insulin A-chain and B-chain was at the leucine13-tyrosine14 bond and the leucine15-tyrosine16 bond, respectively. When the cleavage was completed, three major cleavage sites and three minor cleavage sites on the A-chain, and five major cleavage sites and four minor cleavage sites on the B-chain were found. However, most of the peptides produced after complete hydrolysis of the A- or B-chain by the enzyme were composed of four to six amino acid residues. The results suggest that this enzyme cleaves the oxidized insulin A- and B-chains in a block-cutting manner.

Amino Acids↗

Production and further characterization of an alkaline elastase produced by alkalophilic bacillus strain ya-B.

The characteristics of the obligate alkalophilic Bacillus sp. strain Ya-B, which produces alkaline elastase extracellularly, were examined. This strain grew at pH 7.0 only in the presence of 1% or more NaCl. Its fatty acid distribution pattern was similar to that of other Bacillus species in which iso-C(15) and anteiso-C(15) were the most abundant fatty acids. About 120 mg of enzyme was recovered from 1 liter of culture broth in a medium (pH 10.1) containing mainly glucose, soymeal, and glycerol. The antiserum against this enzyme did not recognize microbial proteinases, such as subtilisins, but reacted with proteinase C, which was purified from commercial pronase. Chemical modification studies revealed that certain histidine and tyrosine residues might be involved in the enzyme activity. This enzyme underwent a partial unfolding at pHs higher than 12.0, as indicated by the circular dichroism study.

Journal Article↗

Antitumor and antimetastatic activity of an antibiotic, ascofuranone, and activation of phagocytes.

Ascofuranone demonstrated antitumor activity against FM3A murine mammary carcinoma, implanted in the peritoneal cavity of syngeneic mice, C3H/He. It was more effective by treatment prior to implantation than by that after implantation. Treatment with ascofuranone also increased splenic cytotoxicity and phagocytic activity of host animal cells. Moreover, ascofuranone induced inflammatory cells in the peritoneal cavity which are mainly composed of polymorphonuclear leukocytes and macrophages. These cells are more potent in cytotoxicity against FM3A cells than with resident peritoneal cells. The antitumor activity of ascofuranone was suppressed by ip administration of silica, just prior to tumor implantation. These results suggest that the prophylactic antitumor activity of ascofuranone is expressed through the activation of phagocytes. Ascofuranone also suppressed pulmonary metastasis of B16 melanoma and Lewis lung carcinoma. Treatment after tumor implantation failed to suppress the metastasis. Single treatment of ascofuranone 4 days prior to implantation decreased the metastasis of Lewis lung carcinoma but not that of B16, whereas single treatment of ascofuranone 24 hours prior to the tumor implantation decreased the metastasis of B16 but not that of Lewis lung carcinoma.

Animals↗

[Preoperative intra-arterial infusion of adriamycin in advanced breast cancer with reference to estrogen receptor status].

Preoperative intra-arterial infusion of adriamycin [I I A] for advanced breast cancer was performed in 22 cases, and correlation of the estrogen receptor (ER) status with the effect of I I A therapy was histologically examined. Fifty-five percent of all cases responded to I I A; 80% of ER-negative cases responded, whereas only 33% of ER-positive cases did. I I A was significantly effective in ER-negative cases (p less than 0.05). The histological effect of I I A was also remarkable in ER-negative cases and was related to the clinical effect. The ER status was thought to be a parameter not only for hormonal therapy, but also for chemotherapy. Additionally, drill biopsy was performed in order to examine the correlation between the therapeutic effect and histological type in 16 cases before I I A therapy. Scirrhous carcinoma was more responsive to the I I A therapy than other histological types.

Adult↗

[Nuclear morphometry of cancer cells in stage III breast cancer with special reference to prognosis].

The nuclear area (NA) and nuclear form factor (NFF) (NFF = 4.pi.NA/P2. Na, nuclear area; P, perimeter) have been measured in fifteen stage III patients with an invasive ductal breast cancer, using an image analyzer (IBAS-2000, Zeiss). The NA has been revealed as being 41.8 +/- 8.82 micrograms2 (mean +/- S.D.) in five-year survivors (n = 8), and 59.4 +/- 12.9 micrograms2 in non-survivors (n = 7). The NFF was found to be 0.74 +/- 0.038 in those who survived, and 0.69 +/- 0.028 in non-survivors. The NA was significantly lager (p less than 0.01) and the NFF significantly lower (p less than 0.05) in the non-survivors than in the survivors. NA and NFF are considered to be helpful in determining the prognosis of breast cancer patients in stage III.

Breast Neoplasms↗

Suppression of hypertriglyceridemia of Ehrlich carcinoma-bearing mice by an antibiotic, ascofuranone.

Ehrlich ascites carcinoma-bearing mice exhibit hypertriglyceridemia. An antitumor antibiotic, ascofuranone, suppressed tumor-induced hypertriglyceridemia when administered i.p. even when no evident antitumor activity was observed without affecting the levels of free fatty acids, phospholipids, cholesterol, glucose, and total protein in plasma. Ascofuranone did not reduce plasma triglycerides of normal mice. Insulin and clofibrate, known modifiers of lipid metabolism, showed no significant suppression. Ascofuranone is also effective on solid tumor-induced hypertriglyceridemia. Another notable change of metabolism affected by tumor-bearing in the early stage where hypertriglyceridemia has not yet fully progressed is hypoglycemia. Although ascofuranone did not affect hypoglycemia, the suppressive effect on hypertriglyceridemia was more evident when ascofuranone was administered in the early stage than in the later stage. These results suggest that ascofuranone suppresses hypertriglyceridemia by specifically affecting the changes of host metabolism which is induced in the early stage of tumor bearing.

Animals↗

Molecular cloning and nucleotide sequence of the 3-isopropylmalate dehydrogenase gene of Candida utilis.

A 3-isopropylmalate dehydrogenase (3-IMDH, EC 1.1.1.85) gene was cloned from a gene library of Candida utilis. One of the plasmids, pYKL30, could complement Escherichia coli leuB and Saccharomyces cerevisiae leu2 auxotrophs; a 2.2 kb HindIII fragment subcloned in pBR322 could still complement the leuB mutation. Southern hybridization confirmed that this fragment was derived from C. utilis. An open reading frame of 1089 bp that corresponded to a polypeptide of 363 amino acids, one residue shorter than the 3-IMDH of S. cerevisiae, was found in the cloned fragment. The homology between the 3-IMDHs of C. utilis and S. cerevisiae was 76.2% in nucleotides and 85.4% in amino acids. In contrast, the homology between the 3-IMDHs of C. utilis and Thermus thermophilus was much smaller and was restricted to some regions of the gene.

3-Isopropylmalate Dehydrogenase↗