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R Nishimura

Publications and source records attributed to R Nishimura.

At least 271 records · Page 15Linked to original sources
PubMed1987

[The characterization of free alpha subunit purified from the urine of normal term pregnant women].

Free alpha subunit (PU alpha) was extracted and purified from the urine of normal term pregnant women, and examined for molecular weight, electric charge, affinity to lectins (ConA, RCA and PNA) and the ability to combine with hCG beta in comparison with hCG alpha dissociated from hCG in vitro. The molecular weight of PU alpha was greater than that of hCG alpha in gel chromatography, but smaller in SDS-PAGE. However the free alpha subunits from the urine of patients with cancer were estimated to be larger than those of hCG alpha by both methods. In isoelectric focusing, while hCG alpha exhibited a neutral charge, PU alpha exhibited a negative charge. After treatment with sialidase, both hCG alpha and PU alpha were shifted to the basic region, indicating that they contained terminal sialic acid residues. The affinity to lectins indicated that PU alpha may contain both asparagine-linked and O-linked oligosaccharides, while hCG alpha contains asparagine-linked oligosaccharide only. PU alpha scarcely showed any combining activity with hCG beta, whereas hCG alpha combined actively. The O-linked oligosaccharide, which is not present in hCG alpha, may cause PU alpha to fail to combine with hCG beta.

Carbohydrates↗
PubMed1987

Characterization of human chorionic gonadotropin in urine of patients with trophoblastic diseases by Western blotting using specific antibodies.

Human chorionic gonadotropin (hCG) from urine of patients with trophoblastic diseases was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by Western blotting using specific antibodies. Western blotting using anti-hCG beta carboxy-terminal peptide (CTP) revealed that the molecular weights of the beta subunits of the three molar hCG samples were identical to that of standard hCG beta, but those of choriocarcinoma hCG samples were individually different. In the five choriocarcinoma hCG samples, the beta subunits of three samples were apparently larger than standard hCG beta, while those of two samples were smaller than standard hCG beta but larger than desialylated standard hCG beta. These results suggest that structural changes of carbohydrates of hCG, which may be induced by malignant transformation of the trophoblast, can be observed as differences in molecular weight. In SDS-PAGE under nonreducing conditions. Western blotting using anti-hCG beta-CTP revealed a single band corresponding to hCG beta. Under reducing conditions with dithiothreitol (DTT), however, a second low-molecular-weight material (called here CTP') could be observed with anti-hCG beta-CTP. All five choriocarcinoma hCG samples were much more susceptible than standard hCG to cleavage of CTP' by DTT. We conclude that estimations of molecular weight and susceptibility to DTT reduction of urinary hCG by Western blotting using specific antibodies are useful in the diagnosis of choriocarcinoma.

Choriocarcinoma↗
PubMed1986

A single amino acid substitution in an ectopic alpha subunit of a human carcinoma choriogonadotropin.

Human choriogonadotropin [hCG] has two dissimilar noncovalently associated subunits, designated alpha and beta. An ectopically secreted hCG alpha subunit that fails to associate with the beta subunit and displays an anomalously high molecular weight on molecular sieve chromatography but not on sodium dodecyl sulfate-polyacrylamide gel electrophoresis has been sequenced. A single substitution of Glu56 by Ala56 has been found in the altered subunit. No evidence for conformational differences between normal and ectopic alpha could be found using circular dichroism or intrinsic fluorescence as measures of secondary and tertiary structure, respectively. Hydrophobicity profiles as determined by the method of Kyte and Doolittle (Kyte, J., and Doolittle, R. F. (1982) J. Mol. Biol. 157, 105-132) predicted, however, that the hydrophilic segment, Thr54-Ser55-Glu56-Ser57-Thr58, becomes an extension of the preceding hydrophobic segment when Glu56 is substituted with Ala. This solitary hemoglobin S-like mutation may lead to an altered tertiary structure, self dimerization, or an alteration in glycosylation that could be responsible for the ectopic alpha subunit's failure to associate with the beta subunit.

Alanine↗
PubMed1986

Photoaffinity labeling of the gonadotropin receptor with native, asialo, and deglycosylated choriogonadotropin.

Human choriogonadotropin (hCG) is a heterodimeric hormone composed of an alpha and a beta subunit. hCG and its asialo (ashCG) and deglycosylated (dghCG) forms vary in their ability to stimulate hormone responsive adenylate cyclase. ashCG is a partial agonist, and dghCG is an antagonist. Photoactivatable moieties were coupled to hCG, ashCG, and dghCG, and the derivatives were radioiodinated. Competitive binding studies indicate that all of the derivatives had a similar affinity for the gonadotropin receptor on porcine granulosa cell membranes. Radiolabeled derivatives were used to photoaffinity label the gonadotropin receptor. Radiolabeled complexes were separated by NaDodSO4/PAGE. All of the derivatives produced similar autoradiographic patterns, except that dghCG produced an additional 48-kDa complex. To investigate the structure of the complexes further, peptide mapping of proteolytic digests was used. All, except for the 48-kDa complex, generated similar peptide maps indicating a relationship between those complexes in which the smaller components are part of the larger. The 48-kDa complex contained both subunits of 40-kDa dghCG. Therefore, this complex is expected to contain an additional component of 8 kDa. The complex was generated whether the hormone-receptor complex was photoaffinity labeled on cells, on isolated membranes, or after solubilizing in detergent. Formation was blocked by excess hCG and did not occur in the absence of UV irradiation. We conclude that the hCG derivatives are able to photoaffinity label the hCG receptor but that the dghCG derivative can photoaffinity label an additional component that was not observed when derivatives of hCG or ashCG were used to label the receptor.

Adenylyl Cyclases↗
PubMed1986

Eccrine adenocarcinoma of the vulva producing isolated alpha-subunit of glycoprotein hormones.

A rare case of adenocarcinoma of the sweat glands of the vulva producing isolated alpha-subunit of glycoprotein hormones is reported. By an immunohistochemical method, eccrine gland adenocarcinoma tissues obtained from the right vulva and from its metastatic lesion in the right subclavicular lymph nodes were found to react with human chorionic gonadotropin (hCG), alpha-hCG but not beta-hCG. The concentrations of alpha-subunit in the serum and urine were markedly elevated to 6000 ng/mL and 55,000 ng/mL, respectively, just before the death of the patient.

Adenocarcinoma↗
PubMed1986

Effective separation of human chorionic gonadotropin subunits by high performance gel permeation chromatography.

Human chorionic gonadotropin (hCG) was effectively separated into alpha and beta subunits by treating with 8 M guanidine hydrochloride, followed by high performance gel permeation chromatography (GPC) on a 2.5 X 60 cm TSK G 3000 SW column in 6 M guanidine hydrochloride. Their molecular weights estimated by GPC were about 29,000 daltons for the beta subunit and 19,000 daltons for the alpha subunit. Both subunits were examined for SDS-polyacrylamide gel electrophoresis, amino acid analyses and radioimmunoassay, respectively. Neither subunit showed significant binding to the hCG-receptor fraction of rat Leydig cell in vitro. However, the separated subunits easily recombined and recovered about 90% of receptor binding activity of intact hCG. The present results indicate that the GPC technique is an effective, simple and non-denaturing method for the separation of hCG into alpha and beta subunits.

Amino Acids↗
PubMed1986

Plasminogen activator as a functional marker for estrogen dependence in human breast cancer cells.

To examine whether plasminogen activator reflects the functional state of estrogen receptors in human breast cancer, the enzyme activities were determined in extracts prepared from 160 breast cancer specimens and compared on qualitative and quantitative bases with the levels of steroid receptors, such as cytoplasmic estrogen receptor (ERC), progesterone receptor (PgR) and nuclear estrogen receptor (ERN). With any receptor, plasminogen activator activity was significantly higher in receptor-positive tumors than in receptor-negative tumors. When these breast tumors were categorized into 8 groups in terms of combinations of receptor status, breast cancers which were positive for all these receptors were found to contain the highest plasminogen activator activity. Furthermore, quantitative analyses demonstrated positive correlations of the enzyme activity with either ERC content (correlation coefficient +0.37, P less than 0.001) or PgR content (correlation coefficient +0.45, P less than 0.001). These results strongly suggest that plasminogen activator can be used as an effective functional marker for hormone dependence in human breast cancer.

Breast Neoplasms↗
PubMed1986

High level of beta-type transforming growth factor activity in human urine obtained from cancer patients.

Activity of transforming growth factor (TGF) in urine was examined by the use of cloned BALB/3T3 A31-1-1 indicator cells. When urine was extracted by an acid-ethanol method, fractionated on a Bio-Gel P-100 column, and analyzed for TGF activity, samples from healthy persons showed no activity, but 80% of the samples from advanced cancer patients had the activity. Activity observed in tumor-bearing patients was eliminated after therapy. Further analysis was carried out in a much simpler way by the fractionation of urine samples after only dialysis and lyophilization. An extensive survey of TGF activity in urine using BALB/3T3 indicator cells revealed weak or intermediate (19%) activity in healthy persons and high (56%) or intermediate (31%) activity in advanced cancer patients. When urine samples were analyzed and compared using both BALB/3T3 cells and NRK 49F cells, the BALB/3T3 cells were shown to form colonies in response to beta-type TGF but not to alpha-type TGF. The present results are the first demonstration of an elevated level of beta-type TGF in urine from cancer patients.

Biological Assay↗
PubMed1986

Clinical evaluation of an immunoradiometric assay for CA15-3 antigen associated with human mammary carcinomas: comparison with carcinoembryonic antigen.

Serum levels of CA15-3, a mammary tumor associated antigen recognized by two different murine monoclonal antibodies (115D8 and DF3), were investigated in patients with mammary carcinoma and other benign or malignant diseases. The reference value of the serum CA15-3 level was obtained as 24 units/ml at the 99% confidence limit among healthy individuals (n = 462). Elevation of serum CA15-3 levels was observed in 24.3% of overall patients with mammary carcinoma. Serum CA15-3 levels in breast cancer patients correlated with the clinical stage; higher percentages of positivity were observed in those with advanced breast cancer (stage IV, 64.7%, recurrent, 52.4% and metastatic, 70.3%). Furthermore, elevated serum CA15-3 levels in breast cancer patients responded well to the effect of therapy. Although the serum CA15-3 test gave percentages of positivity of breast cancer similar to those found by the serum CEA test, the serum CA15-3 test revealed lower percentages of positivity than the serum CEA test among patients with benign breast lesions, liver cirrhosis or other carcinomas. These results suggest that the serum CA15-3 antigen level provides a very useful marker for diagnosis and clinical monitoring of patients with breast cancer.

Adolescent↗
PubMed1985

Significance of the Tritiated Thymidine Labeling Index in breast cancers.

We carried out studies to determine whether the Tritiated Thymidine Labeling Index (TLI) would correlate with hormone receptors as well as with clinical and histological data. Sixty-four patients with breast cancer were the subjects studied. TLI showed no relationship to age, menopausal status, T-factor, n-factor, stage, or histological type. However, compared to tubule formation, nuclear pleomorphism, and mitotic activity, TLI showed a positive correlation with each and accordingly there was a positive correlation between TLI and Bloom's histological grading. The cumulative disease-free rate at three years was higher in case of a TLI below 4.0 (median TLI value). TLI significantly correlated inversely with the binding sites not only of cytoplasmic estrogen receptors (ERC), but also of cytoplasmic progesterone receptors (PRC) and nuclear estrogen receptors (ERN). Cancers negative for all three receptors indicated the highest TLI, while cancers positive for all three receptors showed the lowest TLI. The results suggest that breast cancers positive for hormone receptors were of low malignancy because lower TLI related to a lower proliferative activity. Thus, TLI is an useful parameter for assessing the clinical status of breast cancers.

Binding Sites↗
PubMed1985

Sequential assays of hormone receptors and the Tritiated Thymidine Labeling Index in 7,12-dimethylbenz(a)anthracene-induced rat mammary cancers.

This study was carried out to determine whether hormone receptors and the Tritiated Thymidine Labeling Index (TLI) would change with intervening treatment in 7,12-dimethylbenz(a)anthracen-induced rat mammary cancer as well as to evaluate their predictive significance. Forty-eight tumors were studied. TLI significantly correlated inversely with the binding sites of cytoplasmic estrogen receptors (ERC), but not of cytoplasmic progesterone receptors (PRC). From the response to the two treatments ovariectomy or adriamycin, it was demonstrated that ERC was a predictor of the response to ovariectomy and TLI showed a predictive value in the response to adriamycin. Ovariectomy generally induced a marked decrease in ERC level and PRC level, whereas adriamycin led to an increase and decrease in ERC level and PRC level, respectively. TLI showed a remarkable decrease in tumors which were responsive to ovariectomy or adriamycin. Some tumors, which had been the intermediate or ineffective group with a previously given treatment, were evaluated for the first time as being the effective group with another type of treatment. These results suggest that the response to treatment for breast cancer may change over the clinical course and ideal treatment for advanced breast cancer should included concomitant chemo-endocrine therapy.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1985

Measurement of cutaneous blood flow by clearance of hydrogen gas generated by electrolysis.

In an attempt to assess the reliability of a method for measurement of local blood flow-namely, the clearance of electrochemically generated hydrogen gas-a series of experiments were conducted using the skin and skin flap in rats and rabbits. The results showed high accuracy in obtained values, good reproducibility in the repeated measurements, and consistency with the values obtained by the hydrogen gas inhalation method. Histological examination revealed only minimal damage to the tissue resulting from the measurement. Using this method, blood flow was measured at different sites on the flap in rats. The critical point of blood flow as measured by this method was thoroughly consistent with the dye distance as well as with the survival length. No injurious effects of the measurement procedure on flap survival were noticed. The present study suggests a wide potential application of this method in plastic surgery because of its high reliability and because no radioactivity is involved.

Animals↗
PubMed1985

Free alpha subunits of glycoprotein hormone with dissimilar carbohydrates produced by pathologically different carcinomas.

The two kinds of glycoprotein hormone alpha subunit ectopically produced by an undifferentiated carcinoma of the left femoral region (TM-alpha) and an adenocarcinoma of the right external genitalia (FS-alpha) were examined for amino acid composition, isoelectric focusing, molecular weight, the ability to combine with standard hCG beta and affinity with lectins (Con A, Ricin and PNA). Both TM-alpha and FS-alpha exhibited immunoantigenicity similar to standard hCG alpha. Furthermore, there were no significant differences in the amino acid compositions of TM-alpha, FS-alpha or standard hCG alpha. In isoelectric focusing, while standard hCG alpha exhibited a neutral charge, both TM-alpha and FS-alpha exhibited strong negative charges. FS-alpha was as sensitive to sialidase as standard hCG alpha, whereas most of the TM-alpha exhibited resistance to sialidase. TM-alpha contains sialidase-insensitive peripheral material with a negative charge. The affinity with Ricin-Sepharose indicated that most of the FS-alpha and some of the TM-alpha may contain terminal sialic acid and the penultimate structure, Gal beta 1----4G1cNAc; the affinity with PNA-Sepharose indicated that both may also contain terminal sialic acid and the penultimate structure, Gal beta 1----3GalNAc. These observations suggest that dissimilar glycosylation processes are present in the carcinoma ectopic biosynthesis of glycoprotein hormone alpha subunit.

Adenocarcinoma↗