Biomedical subjects

S Nozawa

Publications and source records attributed to S Nozawa.

At least 19 recordsLinked to original sources

PubMed1992

Structural characteristics of the ceramides of neutral glycosphingolipids in the human female genital tract--their menstrual cycle-associated change in the cervical epithelium and uterine endometrium, and their dissociation in the mucosa of the fallopian tube with the menstrual cycle.

In human cervical epithelium, uterine endometrium, and mucosa of the fallopian tubes, neutral glycosphingolipids were exclusively represented by the globo-series glycosphingolipids, such as CMH, LacCer, Gb3Cer and Gb4Cer, but the molecular species of their ceramide moieties were characteristically altered in the cervical epithelium and uterine endometrium during the menstrual cycle. Individual neutral glycosphingolipids in the cervical epithelium and the uterine endometrium at the follicular phase gave two bands on TLC, whereas those at the luteal phase displayed three bands, the third being the lower migrating one. Neutral glycosphingolipids migrating to the same positions as these lower-migrating bands were constantly detected in the mucosa of the fallopian tubes, independent of the menstrual cycle. The lower-migrating bands for the cervical epithelium and the uterine endometrium at the luteal phase were due to molecules mainly constructed of phytosphingosine with alpha-hydroxy fatty acids having chain lengths of 18-24 and 4-sphingenine with alpha-hydroxy fatty acids having chain lengths of 16-22, whereas those in the mucosa of the fallopian tubes were exclusively N-alpha-hydroxypalmitoyl 4-sphingenine.

Ceramides↗

PubMed1992

Complementary DNA cloning for galactosyltransferase associated with tumor and determination of antigenic epitopes recognized by specific monoclonal antibodies.

The galactosyltransferase associated with tumor (GAT) was the name given to the isoenzyme that tends to polymerize resulting in slower moving in a nondenaturing polyacrylamide gel electrophoresis than normal (beta 1-4)galactosyltransferase (normal GalT). A complementary DNA (cDNA) library was constructed from a human ovarian cancer cell line, RMG-I, which secreted an amount of GAT into the culture supernatant and screened with monoclonal antibodies (MAbs) against GAT and normal GalT. One of six cDNA clones, UG86-1, encoded an epitope recognized by a GAT-specific MAb, 8513. Recombinant proteins expressed by UG86-1 in Escherichia coli also had antigenic epitopes recognized by the other MAbs against normal GalT. The 229-base pair nucleotide sequence encoded by UG86-1 was identical to the stem region sequence of HGT832 which encodes a full-length cDNA of human GalT. Using recombinant proteins directed by deletion mutant cDNAs, the antigenic epitopes recognized by each MAb were determined. The epitope of MAb8628, which reacts to both the GAT and normal GalT, was localized to the COOH-terminal side of proteolytic cleavage site where the membrane-bound form enzyme is cleaved to be converted to soluble forms, while MAb8513 epitope was at the NH2-terminal side from this cleavage site between the COOH-terminal end of the membrane-binding domain and the cleavage site. These results demonstrate that GAT is produced by aberrant proteolytic cleavage at the different site, closer to the membrane-binding domain, from the normal GalT.

Antibodies, Monoclonal↗

PubMed1992

Mouse monoclonal antibodies which recognize a human (beta 1-4)galactosyl-transferase associated with tumor in body fluids.

Mouse monoclonal antibodies against human (beta 1-4)galactosyl-transferase (GalT) purified from human ovarian tumor effusion fluids were prepared and characterized. GalT purified from normal human plasma showed a single diffused band in nondenaturing polyacrylamide gel electrophoresis, but GalT purified from human ovarian tumor effusion fluids showed several oligomeric bands and a monomeric band in nondenaturing polyacrylamide gel electrophoresis. These oligomeric bands were dissociated into monomer by urea treatment and polymerized by a 2-mercaptoethanol treatment. Nine monoclonal antibodies (MAb) were prepared by immunization of purified GalT from human ovarian tumor effusion fluids and classified into three groups. Type I MAbs (MAb8611, MAb8913, and MAb8919) reacted only to the GalT monomer. Type II MAbs (MAb4880, MAb8507, and MAb8628) reacted to both the GalT monomer and the GalT polymer. Type III MAbs (MAb7907, MAb8513, and MAb8677) reacted only to the GalT polymer. These MAbs except MAb7907 could recover GalT enzyme activity from effusion fluids by immunoprecipitation. A fraction passed through MAb8513 affinity chromatography still showed reactivity to MAb8919, demonstrating that an epitope of MAb8513 resides on a minor part of GalT. A sandwich immunoassay (MAb8513-MAb8628HRP) was developed, and serum samples from ovarian cancer patients and benign ovarian patients were tested. The levels of sandwich immunoassay of serum samples from cancer were elevated significantly compared to those from benign and did not necessarily correlate to total GalT enzyme activity in serum samples. These results suggested that MAb8513 (Type III) might recognize a unique GalT associated with tumor (GAT).

Animals↗

PubMed1992

Menstrual cycle-associated expression of 2-hydroxy fatty acyl phytosphingosine-containing GlcCer, LacCer and Gb3Cer in human uterine endometrium.

In the previous study, we found that sulfatide was characteristically expressed in the secretory phase of human uterine endometrium and that the metabolism of glycosphingolipids was strictly controlled by sex steroid hormones. Therefore, the neutral glycosphingolipid composition of human uterine endometrium in the proliferative and secretory phases was analyzed and was found to be characteristic in both phases. The major neutral glycolipids were GlcCer, LacCer, Gb3Cer and Gb4Cer. The concentrations of GlcCer, LacCer and Gb3Cer in the secretory phase were higher than those in the proliferative phase. Furthermore, on TLC, GlcCer, LacCer and Gb3Cer in the proliferative phase gave three bands, the 3rd band, which migrated to the lowest position, being much more predominant in the secretory phase. The individual band materials in both phases were purified by silica gel column chromatography, and their structures were analyzed by FABMS and GLC. The lower-migrating bands of GlcCer, LacCer and Gb3Cer were found to contain molecules with 2-hydroxy fatty acyl phytosphingosine, indicating that hydroxylation of the fatty acid and sphingosine moieties to give 2-hydroxy fatty acid- and phytosphingosine-containing glycosphingolipids, respectively, is induced selectively in the secretory phase on a change in the hormonal environment.

Cerebrosides↗

PubMed1992

CA54/61 as a marker for epithelial ovarian cancer.

Using a new one-step, double-determinant enzyme immunoassay, we performed quantitative measurements of a mucin-type glycoprotein antigen (CA54/61) that we recently detected in sera of ovarian carcinoma patients. When the cutoff value was set at 12 units/ml, at which a high diagnostic efficiency was demonstrated [or at 20 units/ml (mean + 3 SD of healthy females)], the positive rates of ovarian serous, mucinous, clear cell, and endometrioid carcinomas were 76% (or 63%), 63% (or 55%), 57% (or 52%), and 50% (or 38%), respectively. Even in mucinous cystadenocarcinoma, more than one-half of the cases were positive, indicating the potential utility of the assay in the diagnosis of mucinous tumors. In sera from patients with benign ovarian tumors, only 9% (or 4%) of the cases were positive, indicating the quite high specificity of this test for ovarian carcinomas. To make a comparison between CA54/61 and CA125, we set the cutoff level of CA125 at 110 units/ml, at which value a high diagnostic efficiency was demonstrated [or at 35 units/ml (mean + 3 SD of healthy females)]. When both CA54/61 and CA125 were assessed in sera from 36 patients with mucinous cystadenocarcinoma, the positive rates of CA54/61 and CA125 were 64% (or 56%) and 36% (or 56%), respectively, suggesting that CA54/61 is of clinical value as a new tumor marker for ovarian cancers, including mucinous tumors.

Adult↗

PubMed1992

Human uterine endometrial adenocarcinoma: characteristic acquirement of synthetic potentials for II3SO3-LacCer and ganglio series sulfoglycosphingolipids after transfer of the cancer cells to culture.

The acidic glycosphingolipid composition of human uterine endometrial adenocarcinoma was compared with those of normal uterine endometrium at the proliferative and the secretory phases. Upon chemical composition analysis, no significant transformation-associated change of these glycolipids was observed. However, when cancer cells from the patients with human uterine endometrial adenocarcinoma were transferred to culture, the composition of glycosphingolipids, particularly sulfoglycosphingolipids, was significantly altered after the 70th doubling time. I3SO3-GalCer, which was contained in the original tissues of uterine endometrial adenocarcinomas, disappeared completely from the cultured cells at the 70th doubling time, whereas II3SO3-LacCer and ganglio series sulfoglycosphingolipids, which were originally contained in a trace amount or not present at all in the cancer tissues, became the major components in the total acidic glycosphingolipids in the cultured cells. Also, among cell lines established from several gynecological cancers, which include uterine cervical squamous carcinoma, uterine endometrial adenocarcinoma, ovarian clear cell carcinoma, choriocarcinoma, uterine sarcoma, ovarian sarcoma, and vulvar melanoma, only those cells derived from uterine endometrial adenocarcinoma expressed II3SO3-LacCer and ganglio series sulfoglycosphingolipids and the synthetic activities of these sulfoglycolipids, indicating that uterine endometrial adenocarcinoma cells characteristically lose the sulfotransferase to GalCer and acquire the sulfotransferase to LacCer after being transferred to culture in vitro. Thus, the unique sulfoglycosphingolipids and sulfotransferase are useful markers for the characterization of uterine endometrial adenocarcinoma among human gynecological cancers.

Adenocarcinoma↗

PubMed1992

Glycosphingolipids of various human ovarian tumors: a significantly high expression of I3SO3GalCer and Lewis antigen in mucinous cystadenocarcinoma.

Among several human ovarian tumors, which include mucinous cystadenocarcinoma, serous cystadenocarcinoma, and clear cell adenocarcinoma, the mucinous cystadenocarcinoma showed a unique glycosphingolipid composition. In particular, more than 90% of the acidic glycosphingolipids in the mucinous cystadenocarcinoma is comprised of sulfolipids, which are hardly detected in normal ovary and are contained in concentrations of less than 40% in the other type of ovarian tumors. By means of negative ion fast atom bombardment mass spectrometry and gas liquid chromatography, the major sulfolipid in mucinous cystadenocarcinoma is confirmed to be I3SO3-GalCer with N-cerebronoyl phytosphingosine, that which contrasts with I3SO3-GalCer with N-nonhydroxy fatty acyl sphingosine as the major molecular species in the other ovarian cancers. In mucinous cystadenocarcinoma, galactosylceramide is found in the relatively high concentration and is also composed of N-cerebronoyl phytosphingosine. In addition, the concentrations of glycolipids with Le(a) and Le(b) antigenicities are significantly higher in mucinous cystadenocarcinoma than those in normal ovary and the other ovarian tumors.

Chromatography, Thin Layer↗

PubMed1992

Influence of oophorectomy on serum levels of sex steroids and bone metabolism and assessment of bone mineral density in lumbar trabecular bone by QCT-C value.

The present cross-sectional study was carried out to determine the influence of oophorectomy (OPX) on serum levels of sex steroids and bone metabolism, as well as bone mineral density (BMD), in OPX subjects in comparison with age- and body size-matched controls. Quantitative computed tomography (QCT) and dual-photon absorptiometry (DPA) demonstrated a remarkable reduction in BMD in OPX subjects. In particular, the QCT of the centrum of vertebral bone (QCT-C) in these subjects was no more than 69.33 +/- 3.40% (X +/- SEM) of the control value, and this parameter was much lower than the QCT integral (QCT-I) value of total lumbar vertebrae. This means that BMD decreases specifically in spongy portions after OPX. The serum level of estrone (E1) was significantly lower in OPX subjects than in controls. The hormonal action of E1 on target organs has been thought to be only one-third of that of estradiol (E2), but the marked reduction in serum E1 level seemed to be a significant cause of the reduction in BMD. The serum level of androstenedione (delta 4) significantly decreased in OPX subjects and appeared to affect bone metabolism negatively. Both bone formation and bone resorption were found to be stimulated following OPX, but the rate of bone resorption was found to be higher than that of bone formation: there was an imbalance between bone formation and bone resorption in OPX subjects. However, it was not possible to prove a relationship between Ca regulating hormone and this phenomenon. In conclusion, the QCT-C value reflects the changes in spongy vertebral BMD more sensitively than the QCT-I value or DPA.(ABSTRACT TRUNCATED AT 250 WORDS)

Androgens↗

PubMed1992

Protein phosphorylation regulates the mouse sperm acrosome reaction induced by the zona pellucida.

Recently, the ligand-receptor signal transduction mechanism has been implicated in mediating the zona pellucida (ZP)-induced acrosome reaction. Little is known about the role of protein phosphorylation in this specific event. We examine whether modification of protein phosphorylation and dephosphorylation affects the kinetics of the acid-solubilized ZP-induced acrosome reaction of mouse sperm. Mouse epididymal sperm were incubated in modified Krebs-Ringer bicarbonate medium for a period of 90 to 120 min and then treated with 2 acid-solubilized ZP/microliters for an additional 60 min. The chlortetracycline fluorescence assay was used to monitor the acrosome reaction. Capacitated sperm were inhibited from undergoing acid-solubilized ZP-induced acrosome reaction in the presence of an inhibitor of cyclic nucleotide-dependent protein kinase, H8; activators of the Ca(2+)- and phospholipid-dependent protein kinase (protein kinase C); an inhibitor of phosphatases 1 and 2A, okadaic acid; or an inhibitor of protein tyrosine kinases, genistein. The addition of inhibitors of protein kinase C, such as staurosporine, H7, and protein kinase C [19-36] pseudosubstrate, inhibited the phorbol ester-dependent inhibition of the acid-solubilized ZP-induced acrosome reaction. The present study suggests that protein phosphorylation and dephosphorylation play a regulatory role in the process of the ZP-induced acrosome reaction.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1992

Effects of modulators of protein kinases and phosphatases on mouse sperm capacitation.

We examined effects of modulators of protein kinases and phosphatases on the kinetics of mouse sperm capacitation. The chlortetracycline fluorescence assay was used to monitor the process of capacitation (in terms of the appearance of the B pattern). The treatment of sperm with dibutyryl cyclic AMP (cAMP) or dibutyryl cGMP resulted in a higher percentage B pattern at various times during capacitation compared with the control. The addition of 100 microM H8 inhibited the cyclic nucleotide-dependent stimulation of capacitation. Tumor promotors, 12-O-tetradecanoyl phorbol 13-acetate (TPA; a stimulator of protein kinase C) and okadaic acid (an inhibitor of protein phosphatases 1 and 2A), induced a rapid appearance of the B pattern (15 min after addition) and maintained a percentage B pattern similar to that of the control in the later period of capacitation. An inhibitor of protein kinase C, staurosporine, inhibited the TPA-dependent acceleration of capacitation. Furthermore, the addition of genistein, an inhibitor of protein tyrosine kinases, resulted in a strong inhibition of capacitation. All agents tested did not affect sperm motility. These data suggest that protein phosphorylation and dephosphorylation may play regulatory roles in mediating mouse sperm capacitation.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1992

Which is more osteoporosis-inducing, menopause or oophorectomy?

The present study was designed to investigate in a comparative manner whether menopause or oophorectomy (OPX) would be a more osteoporosis-inducing factor with regard to sex steroids, bone metabolism and bone mineral density (BMD), including postmenopausal subjects, OPX subjects and age- and body-size-matched premenopausal controls. Serum levels of estradiol (E2), testosterone (TS) and dehydroepiandrosterone (DHEA) were found to decrease in both the postmenopausal and OPX subjects without any significant difference between them, while serum levels of estrone (E1) and androstenedione (delta 4), which have been reported to be related to bone metabolism, were significantly lower in the OPX subjects than in the postmenopausal subjects. According to the indices representing bone formation and bone resorption, as well as the changes in serum levels of Ca-regulating hormones, bone metabolic balance seemed to be slightly more negative in the former than in the latter. However, there was no difference between these two groups of subjects with regard to BMD in lumbar vertebral spongy portion which sensitively reflects the changes in total lumbar BMD and bone metabolism and in which compressive fracture is apt to occur. This fact suggests that these two groups of subjects may be managed in the same way in clinical practice. In other terms, the menopause, a natural event in women, influences BMD as much as OPX, which is the greatest risk factor in osteoporosis, does.

Androgens↗

PubMed1992

Flow-cytometric analysis of immune cell populations in human decidua from various types of first-trimester pregnancy.

We undertook an investigation in which flow cytometry was used to characterize immune cell populations in the decidua of first-trimester normal pregnancies, spontaneous abortions, and ectopic pregnancies in comparison to the nonpregnant endometrium to demonstrate how the proportions of immunocompetent cell populations at the fetomaternal interface are influenced by the presence and state of a fetoplacental allograft. No significant differences were found in the decidua of the different types of first-trimester pregnancy in the proportions of the CD45+, CD14+, CD3+, CD4+, CD8+, CD19+, CD3-/CD16+ and/or CD56+, CD3+/CD16+ and/or CD56+, CD4+/Leu-8+, CD4+/Leu-8-, CD8+/CD11b+, CD8+/CD11b-, and CD3+/HLA-DR- decidual leukocyte subsets. However, the percentage of decidual CD3+/HLA-DR+ cells, which are characteristic of activated T cells, was significantly higher in spontaneous abortions than in normal pregnancies (p less than 0.05). This suggests that the accumulation of decidual leukocytes may be regulated mainly by hormones and/or cytokines rather than by the presence and state of an intrauterine conceptus and that on/off-switching of activation of decidual T cells may be associated with successful maintenance of the implanted embryo.

Abortion, Spontaneous↗

PubMed1992

Modulation of progesterone secretion by androgens in porcine granulosa cell cultures.

The influence of testosterone, androstenedione and dihydrotestosterone (DHT) on the progesterone (P4) production by cultured porcine granulosa cells was studied in the presence or absence of gonadotropins. Porcine granulosa cells from large follicles (6-12 mm in diameter) were incubated for 2 days with 5% CO2 in air with testosterone, androstenedione and DHT (10(-12), 10(-10), 10(-8) and 10(-6) M) in the presence or absence of luteinizing hormone (LH, 10 ng/ml) or follicle-stimulating hormone (FSH, 30 ng/ml). P4 and pregnenolone (P5) in conditioned culture media were quantified by their specific RIAs. In the absence of gonadotropins, P4 in media with androgens were not significantly different from controls. In the presence of LH, the addition of testosterone (10(-10), 10(-8) M), androstenedione (10(-8) M) and DHT (10(-8) M) caused a significant 1.3- to 2.3-fold increase in P4 over that caused by LH alone. In contrast, in the presence of FSH, testosterone (10(-12), 10(-10) M), androstenedione (10(-12)-10(-6) M) and DHT (10(-6) M) reduced the levels of P4 by 22% to 41%. The addition of androgens with LH caused a significant increase in P5, while P5 decreased in the presence of FSH. P4/P5 ratios remained unchanged in the presence of both LH and FSH. These data suggest that the P4 production by cultured porcine granulosa cells is modulated in a paracrine or an autocrine fashion by androgens in the presence of gonadotropins, and that androgens may exert their actions partly by altering the activity of cholesterol side chain cleavage enzymes.

Androgens↗

PubMed1992

Role of corpus luteum function in embryo implantation.

The present study was undertaken to evaluate the role of corpus luteum function in the implantation process of cryopreserved embryos. Six patients with tubal infertility were studied, with a total of 27 fresh embryos being replaced following controlled ovarian hyperstimulation and in vitro fertilization. These embryo transfers failed to produce pregnancy. From the patients, 22 supernumerary embryos were cryopreserved and 10 viable frozen-thawed embryos were transferred in a subsequent natural cycle, resulting in 2 pregnancies. In 1 of the pregnancies, the serum concentrations of estradiol (E2) and progesterone (P4) in the midluteal phase were 29 pg/ml and 5.6 ng/ml, respectively. These values were considered to be below the physiological range. These data suggest that a pregnancy can be achieved in spite of low circulating E2 and P4 levels during the luteal phase, which are generally indicative of the luteal phase defect.

Adult↗

PubMed1992

Intravascular pancuronium bromide infusion for prenatal diagnosis of twin-twin transfusion syndrome.

The diagnosis of twin-twin transfusion syndrome remains a problem. Intravascular infusion of pancuronium bromide, a nondepolarizing neuromuscular blocking agent, for the smaller of a set of twins demonstrated paralysis of both twins in one case. However, in a second case, paralysis was shown only in the smaller twin who demonstrated no transplacental vascular communications postnatally. We suggest that infusion of pancuronium bromide, 'pancuronium test', is a simple and safe method for confirming transplacental communications and aids in the diagnosis of twin-twin transfusion syndrome.

Adult↗

PubMed1992

[Development of a new supplementary diagnostic method for endometrial cancer by flow cytometry employing anti-endometrial cancer antibody, MSN-1 and MSN-3].

In cytology, it is often difficult to make a definite diagnosis of endometrial cancer. In order to devise a new supplementary method, using flow cytometry we analyzed the reactivities of endometrial cells with two monoclonal antibodies (MSN-1 and MSN-3), both of which are strongly reactive to endometrial cancer cells. Employing either or both antibodies in flow cytometry, we investigated the usefulness of this analysis for distinguishing endometrial cancer cells from normal endometrial cells. Results revealed a low positive rate for normal endometrium: 9.2% with MSN-1 and 5.0% with MSN-3. In contrast, for endometrial cancer the positive rate was high: 81.2% with MSN-1 and 43.8% with MSN-3. Combined analysis with both antibodies increased the positive rate for endometrial cancer to 93.7%. These results suggest that analysis by flow cytometry employing MSN-1 and MSN-3 may have a diagnostic value for endometrial cancer. We are also investigating the usefulness of two-color analysis using these antibodies.

Antibodies, Monoclonal↗

PubMed1992

[Flow cytometric analysis of cellular DNA content in epithelial ovarian cancer].

Tumor DNA content (ploidy) was determined by flow-cytometry (FCM) on tissue from 32 epithelial ovarian cancer patients. Staining for DNA analysis was achieved with Propidium Iodide. Peripheral blood lymphocytes were used as reference diploid cell population. Of the 32 patients, 26 (81.3%) had tumors which were aneuploid, whereas 6 (18.7%) were diploid. DNA aneuploid cell lines were found in 100% of serous adenocarcinoma, in 57% of mucinous adenocarcinoma, in 67% of endometrial adenocarcinoma, in 88% of clear cell carcinoma and in 75% of undifferentiated carcinoma. The DNA ploidy abnormalities differed in each histologic characteristic of epithelial ovarian cancer.

Adenocarcinoma↗

PubMed1992

Exogenous Thy-1.1 expression as a marker for thymocyte maturation in transgenic mice.

We established a line of transgenic mice carrying the exogenous mouse Thy-1.1 gene (8.2 Kb Eco RI genomic DNA fragment). In these mice, Thy-1.1 was expressed on thymocytes but not on peripheral T cells, presumably due to the lack of cis-acting element(s) on the microinjected genomic DNA. Even in the thymus, however, while most of the CD3/TCR- thymocytes were positive for the transgenic Thy-1.1 gene expression, the CD4+ or CD8+ single positive (SP) thymocytes were composed of two groups, one Thy-1.1+ and one Thy-1.1-, suggesting that the former belongs to cells at premature stages of terminal T cell differentiation. There was no difference in the amount of CD3/TCR complexes expressed on two such SP thymocyte subsets. In the double negative (DN) thymocytes, all the CD3/TCR+ cells were Thy-1.1-. These results suggest that the maturational process of CD3+ DN thymocytes differs from that of SP thymocytes. The unique distribution of Thy-1.1+ population among CD3+ thymocytes suggests that the transgenic Thy-1.1 gene expression can serve as a useful marker to examine terminal maturation processes of CD3+ thymocytes.

Animals↗