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S Yazawa

Publications and source records attributed to S Yazawa.

At least 73 records · Page 4Linked to original sources
PubMed1996

Alpha 2-->3sialyltransferase associated with the synthesis of CA 19-9 in colorectal tumors.

BACKGROUND: A novel assay method specific for alpha 2-->3sialyltransferase that seems to be responsible for the synthesis of CA 19-9 antigen was developed and the levels of the enzyme in colorectal tumor tissues were measured and compared with the levels of alpha 1-->4fucosyltransferase and the CA 19-9 antigen. METHODS: Lacto-N-biose I (Gal beta 1-->3GlcNAc beta, Lewis(c) [Le(c)]) and 6-O-methyl-Le(c) (Gal beta 1-->3[6OMe]GlcNAc beta) were synthesized and covalently attached to bovine serum albumin (BSA). These two substrates were incubated with extracts from colorectal tissues in the presence of cytidine 5'-monophospho-N-acetylneuraminic acid (CMP-NeuAc) and their resulting products were detected by a sequential use of anti-BSA monoclonal antibody-coated beads and 125I-labelled anti-sialylated Le(c) antibody. Levels of alpha 2-->3sialyltransferase and alpha 1-->4fucosyltranferase activities and CA 19-9 antigen were measured in the extracts from colorectal tumors and their adjacent normal tissues. RESULTS: 6-O-Methyl-Le(c)-BSA showed a strong acceptor activity compared with Le(c)-BSA and was used as a specific acceptor for alpha 2-->3sialyltransferase. Similar elevation patterns alpha 2-->3sialyltransferase activities and CA 19-9 antigen levels were observed in tumor extracts but no clear correlation was present between the level of alpha 1-->4fucosyltransferase activities and CA 19-9 antigen levels were observed in tumor extracts but no clear correlation was present between the level of alpha 1-->4fucosyltransferase activities and CA 19-9 antigen levels in the same extracts. CONCLUSIONS: The accumulation of CA 19-9 antigen in colorectal tumors might be caused mainly by the activation of alpha 2-->3sialyltransferase but not by that of alpha 1-->fucosyltransferase.

Acetylglucosamine↗
PubMed1996

Elevation of an alpha(1,3)fucosyltransferase activity correlated with apoptosis in the human colon adenocarcinoma cell line, HT-29.

We studied changes in the carbohydrate expression following apoptotic cell death induced by treatment with interferon (IFN)-gamma and anti-Fas antibody using human colon adenocarcinoma HT-29 cells. An apoptotic cell death of HT-29 accompanied with typical DNA fragmentation was observed when the cells, were cultured sequentially with IFN-gamma and anti-Fas antibody. In flow cytometric analyses, the expression of Le(x) and Le(y) antigen was strongly and slightly enhanced, respectively, on the cell surface in accordance with the apoptosis. When the fucosyltransferase (Fuc-T) activities of the lysates from the treated cells were examined relative to those from untreated cells, a 2.5-fold increase of alpha(1,3)-Fuc-T activities and a slight increase of alpha(1,2)-Fuc-T activities were observed, but little or no increase of alpha(1,4)-Fuc-T activity was detected. In Northern blot analyses using probes for Fuc-T III, IV, V, VI and VII genes, strong RNA messages for Fuc-T III, V and/or VI and a weak RNA message for Fuc-T IV were detected in the untreated HT-29 cells. On the other hand, in the treated cells, the messages for Fuc-T III, V and/or VI were found to almost disappear and the 2.3 kb message for Fuc-T IV was observed to elevate 2.8-fold. Therefore, we suggest that the strongly increased expression of Le(x) antigen found on the HT-29 cell surface might be involved in the process of apoptosis, and that the enhancement of the antigen expression seems to result from the increased activity of alpha(1,3)-Fuc-T encoded mainly by the Fuc-T IV gene.

Adenocarcinoma↗
PubMed1996

Histo-blood group Lewis genotyping from human hairs and blood.

The expression of histo-blood group Lewis antigens is determined by the Lewis-type alpha 1-->3/4fucosyltransferase (Le enzyme) encoded by Fuc-TIII gene (Le gene). The genotyping of Le genes by the PCR-RFLP methods established recently and partly modified in this study was found to be useful not only for determining the genuine Lewis blood types of samples such as human hairs and blood stains but also for distinguishing non-genuine Lewis-negative phenotypes frequently observed in pregnant women from genuine ones. The availability of the present PCR-RFLP methods for the paternity tests was also discussed.

Base Sequence↗
PubMed1996

Presence of granulosa cells during oocyte maturation improved in vitro development of IVM-IVF bovine oocytes that were collected by ultrasound-guided transvaginal aspiration.

The effects of granulosa cells in maturation media on male pronuclear formation and in vitro development of in vitro-matured and fertilized (IVM-IVF) bovine oocytes were examined. In Experiment 1, cumulus-oocyte complexes (COCs) were aspirated from follicles of slaughterhouse ovaries and classified into 4 morphological categories according to the surrounding cumulus cells: Grade 1 (> 4 layers), Grade 2 (3 to 4 layers), Grade 3 (1 to 2 layers) and Grade 4 (denuded). Oocytes were co-cultured with or without granulosa cells (1 x 10(6) cells/ml) for 21 to 22 h. At 18 and 192 h after insemination, the abilities of oocytes to form a male pronucleus and develop up to the blastocyst stage in vitro were determined, respectively. The presence of granulosa cells during maturation did not affect (P < 0.05) the ability of oocytes in Grades 1 and 2 to form a male pronucleus and to develop to the blastocyst stage in Grades 1 and 4. However, the incidence of male pronuclear formation in Grades 3 and 4 and in vitro development to the blastocyst stage in Grades 2 and 3 was higher (P < 0.05) when COCs were cultured in the presence of granulosa cells than when cultured in the absence of granulosa cells. In Experiment 2, COCs collected by ultrasound-guided aspiration were co-cultured with or without granulosa cells, fertilized and cultured as described above. The incidence of blastocysts at 192 h after insemination was higher (P < 0.05) when COCs were cultured for maturation in the presence of granulosa cells (24%) than in the absence of granulosa cells (12%). These results demonstrate that supplementation of maturation medium with granulosa cells improves the quality of oocytes with relatively few cumulus cell layers, as determined by male pronuclear formation and in vitro development. We also conclude that this supplementation effectively improves the developmental ability of bovine IVM-IVF oocytes that were collected by ultrasound-guided transvaginal aspiration.

Journal Article↗
PubMed1996

Production and transfer of IVF embryos from individual inhibin-immunized cows by ultrasound-guided transvaginal follicular aspiration.

Ultrasound-guided transvaginal follicular aspiration (UTA) was performed on 8 multiparous Japanese Black cows which had not been successful in a conventional superovulation program. These cows were actively immunized with a synthetic peptide replica of porcine inhibition alpha N1-26 (pINH) conjugated with rabbit serum albumin (RSA) using Freund's complete adjuvant. Booster injections of the peptide were given at 6, 10, 14 and 20 wk after the primary injection. Twelve follicular aspirations were performed between 10 and 33 wk after the primary injection. Cumulus-oocyte complexes (COCs) were aspirated from follicles > or = 2 mm in diameter. The recovered COCs were classified into 5 categories according to the surrounding cumulus cells: Grade 1 (> 4 layers), Grade 2 (3 to 4 layers), Grade 3 (1 to 2 layers), Grade 4 (denuded) and Grade 5 (expanded and fluffy cumulus cell mass or degenerated ooplasm). The recovered COCs available for in vitro fertilization (IVF; Grades 1, 2, 3 and 4) were matured with granulosa cells (1 x 10(6) cells/ml) for 20 to 23 hr, fertilized with frozen-thawed spermatozoa, and cultured in vitro. At day 7 after insemination, a portion of the embryos were transferred to Holstein heifers. There were great variations among donors in the number of recovered COCs in the numbers of COCs in each grade, and also in the developmental ability of fertilized COCs. IVF procedures were carried out on 685 oocytes and produced 120 embryos (17.5%). The transfer of 36 fresh IVF embryos resulted in 20 pregnancies (55.6%) at 60 days after the transfer. This study has demonstrated first, that the number of COCs collected from individual inhibin-immunized cows by UTA greatly varies among donors. Second, recovered COCs vary greatly in the classification of the morphological categories of surrounding cumulus cell mass among donors and had different developmental abilities when they were cultured after fertilization in vitro. Third, the production of pregnancy in previously nonproductive problem donors is possible using the UTA technique.

Animals↗
PubMed1995

Identification and purification of a novel phospholipid/ganglioside-binding protein in rabbit serum.

We have isolated a novel phospholipid/ganglioside-binding protein from rabbit sera or platelet-free plasma. Using an affinity chromatography of a commercial gel (Sephacryl S-series gel, Pharmacia) column and a preparative polyacrylamide gel electrophoresis, the protein can be easily purified. The protein agglutinates human red cells irrespective of the ABO blood types, and its hemagglutination reaction is specifically inhibited by some phospholipids (phosphatidylserine and phosphatidylglycerol) and ganglioside (N-acetylneuraminyl-galactosylglucosyl ceramide, GM3). The hemagglutination and its inhibition reactions are independent on any divalent cations (Ca2+, Mg2+, Mn2+, Ni2+). The protein seems to be assembled as multimers of disulfide-bonded molecular of 86 kDa and 59 kDa subunits.

Animals↗
PubMed1995

Genetic and enzymatic evidence for Lewis enzyme expression in Lewis-negative cancer patients.

It has been observed that the frequency of individuals with Lewis-negative erythrocytes is significantly higher in cancer patients than in healthy controls. In this study, 20 of the 66 (30.3%) patients with various cancers were typed as Lewis negative from their erythrocytes, while the same frequency in healthy controls was 11.1%. These 20 patients were divided into three groups based on the presence of Lewis blood group antigens and alpha 1-->4-fucosyltransferase in their salivas: group I, 6 patients who had both Lewis antigens and alpha 1-->4-fucosyltransferase activity; group II, 8 patients who had no Lewis antigens but possessed alpha 1-->4-fucosyltransferase activity; group III, 6 patients who had neither Lewis antigens nor alpha 1-->4-fucosyltransferase activity. The genotyping of Le genes by the PCR-RFLP methods, which have been developed and established by us recently, demonstrated that all 14 patients from groups I and II possess Le gene homozygously (Le/Le) or heterozygously (Le/le), whereas all 6 patients from group III were le/le homozygotes. Only the 6 patients from group III were identified as the genuine Lewis-negative individuals. The immunohistochemical staining of the colorectal tumors also showed that the Lewis antigens could be detected on the tumors from groups I and II but not from group III.

Base Sequence↗
PubMed1995

Fucosyltransferase of the peritoneum contributed to the adhesion of cancer cells to the mesothelium.

Adhesion molecules associating with peritoneal dissemination were investigated using human gastric (MKN45 and MKN74) and colon (KM12C and KM12SM) cancer cells and the mouse peritoneum. Adhesion of cancer cells to the peritoneum was determined by a recently reported novel ex vivo method. MKN45 cells established from poorly differentiated adenocarcinoma with less glycosylated sugar chains on their cell surface showed higher adhesion activities to the peritoneum ex vivo and produced large amount of metastases in the abdominal cavity of nude mice, whereas MKN74 cells from differentiated adenocarcinoma with more glycosylated sugar chains showed slightly low adhesion activity. KM12SM cells with highly metastatic potential to liver showed fairly low adhesion activity to the peritoneum compared with KM12C cells. The mouse peritoneum was found to contain alpha 1 --> 2, alpha 1 --> 3, and alpha 1 --> 4 fucosyltransferases, and adhesion of cancer cells was observed to the cellulose ester membrane, on which partially purified alpha-fucosyltransferases from mouse peritoneum were immobilized. The adhesion of cancer cells to fucosyltransferase-immobilized membrane was specifically inhibited by the addition of oligosaccharides and glycoproteins, which could serve as substrates for alpha-fucosyltransferases. These results indicate the contribution of alpha-fucosyltransferases to the adhesion of disseminated cancer cells to the peritoneum and support the possibility of antiadhesion therapy of peritoneal dissemination by treatment with substrates for alpha-fucosyltransferases.

Adenocarcinoma↗
PubMed1995

Binding of bacterial toxins to glycoproteins in the envelopes of rainbow trout eggs.

The ability of the vitelline and fertilization envelopes of rainbow trout eggs to trap toxins was investigated using cholera enterotoxin B and staphylococcal enterotoxin B in cytochemical or immunocytochemical experiments. Extracts from both envelopes were investigated by immunoblot analysis to identify toxin-binding proteins after SDS-PAGE. Binding studies of cholera enterotoxin B to vitelline envelopes and fertilization envelopes revealed a greater reactive intensity in the former. Treatment with neuraminidase enhanced the reactive intensity (or deposit) in the vitelline envelope and fertilization envelope outermost layers, with more conspicuous reactivity in the former. Cytochemical experiments showed that exogenous ganglioside GM1 considerably enhanced cholera enterotoxin B binding to vitelline and fertilization envelopes. This enhancement was shown by an intense reactivity following the occurrence of new binding sites on the vitelline envelope inner surface and the inner wall of the zona radiata, a simultaneous extreme reduction in the reactivity of the vitelline envelope outermost layer, and a striking increase in reactive products in the fertilization envelope outermost layer. The surface region of the vitelline or fertilization envelope outermost layer was the binding site for staphylococcal enterotoxin B, and neuraminidase treatment caused a considerable reduction of reactive products in these areas. Immunoblot analysis of cholera enterotoxin B- or staphylococcal enterotoxin B-binding substances in extracts from the vitelline envelopes or fertilization envelopes demonstrated that the great majority of the binding substances are glycoproteins. The present results suggest that glycoproteins constituting the vitelline envelope or fertilization envelope may contribute to the protection of the egg itself or the embryo by trapping noxious toxins.

Animals↗
PubMed1995

Increased plasma alpha (1 --> 3)-L-fucosyltransferase activities in patients with hepatocellular carcinoma.

Alpha (1 --> 3)-L-fucosyltransferase (alpha 1,3FT) activity was determined in plasma of patients with chronic liver diseases, namely, chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC), The plasma alpha 1,3FT activity was significantly higher (p < 0.01) in chronic liver diseases than that in normal controls. The enzyme activity in plasma of patients with HCC was also significantly higher than that in LC (p < 0.05) or that in CH (p < 0.01). However, no significant difference was observed in the enzyme activity between LC and CH. Plasma alpha 1,3FT activity in patients with HCC was not significantly changed before and after transcatheter arterial embolization. In addition, the enzyme activity in the homogenate of the cirrhotic liver tissue was higher than that in the preparation of the hepatoma tissue in the same patient. These results suggest that the increased plasma alpha 1,3FT activity in patients with HCC reflects mainly the enzyme activity of cirrhotic liver tissue, not that of hepatoma tissue. The significance of the elevated levels of plasma alpha 1,3FT and its decreased hepatoma tissue activity in patients with HCC, compared with that in LC, remains to be clarified.

Aged↗
PubMed1995

Enzymatic basis for the accumulation of Lewis(b) antigen in uterine endometrial cancer.

In order to clarify the mechanism of the abnormal expression of Lewis(b) antigen, which was specific for uterine endometrial cancer tissue, the activities of alpha 1-->2fucosyltransferase, alpha 1-->3fucosyltransferase, and alpha 1-->4fucosyltransferase in normal endometrial tissues and uterine endometrial cancer tissues were determined. Further, an immunocytochemical study of the expression of blood group-related carbohydrate antigens in 6 cultured cell lines derived from various gynecologic malignant tumors was performed and the alpha 1-->2fucosyltransferase, alpha 1-->3fucosyltransferase, and alpha 1-->4fucosyltransferase activities of these cell lines were determined. Compared with normal endometrium, uterine endometrial cancer tissues showed significantly higher values of alpha 1-->2fucosyltransferase, alpha 1-->3fucosyltransferase, and alpha 1-->4fucosyltransferase activities. The specifically strong expression of type I carbohydrate chains, particularly the Lewis(b) antigen, was recognized in cultured cell lines derived from uterine endometrial cancer. Compared with those cell lines derived from uterine cervical cancer and ovarian cancer, the cultured cell lines derived from uterine endometrial cancer showed higher activities of alpha 1-->2fucosyltransferase and alpha 1-->4fucosyltransferase, which are enzymes related to the synthesis of Lewis(b) antigen. The cell lines derived from uterine endometrial cancer showed specifically high values of alpha 1-->4fucosyltransferase activity. These results suggest that the alpha 1-->2fucosyltransferase and alpha 1-->4fucosyltransferase activities, especially the alpha 1-->4fucosyltransferase activity, contribute to the abnormal expression of the Lewisb antigen in uterine endometrial cancer.

Antigens, Neoplasm↗
PubMed1995

Thyroid anaplastic carcinoma producing granulocyte-colony-stimulating factor and parathyroid hormone-related protein.

A 65-year-old woman noticed a rapidly enlarging neck mass with tenderness and complained of dyspnea. She was diagnosed as having anaplastic thyroid carcinoma. She died of respiratory failure 14 days after admission. Marked leukocytosis and hypercalcemia were observed in the clinical course. Both serum granulocyte-colony-stimulating factor and parathyroid hormone-related protein levels were elevated. The cancerous tissue was also immunohistochemically stained for both peptides. We conclude that the leukocytosis and hypercalcemia of this patient were induced by these two factors produced by the tumor.

Aged↗
PubMed1995

[A case of acute cerebellar ataxia with abnormal single photon emission computed tomography].

A 35-year-old woman complained of acute progressive speech and gait disturbance after an upper respiratory tract infection. Neurological examination revealed cerebellar dysarthria, horizontal saccadic pursuit and slow saccadic eye movement, marked truncal ataxia, generalized hyperreflexia and mild sensory impairment of the bilateral lower limbs. She was diagnosed as having acute cerebellomyelitis. We considered her status as acute cerebellar ataxia. The neurological signs and symptoms rapidly improved with intravenous administration of high dose of glucocorticoid. Single photon emission computed tomography (SPECT) using 99mTc-HMPAO was performed on the 9th day and 50th day from the neurological onset. It showed an increased accumulation of 99mTc-HMPAO in the bilateral cerebellar hemispheres and vermis on the 9th day in spite of normal findings of Gd-DTPA enhanced MRI. Less accumulation was seen on the 50th day when her neurological signs almost improved. The accumulation may suggest the inflammatory process of the cerebellum. SPECT can be a useful method for evaluating the severity of cerebellitis.

Adult↗
PubMed1994

Molecular genetic analysis of the human Lewis histo-blood group system.

The expression of Lewis histo-blood group antigen is determined by the Lewis type alpha(1,3/1,4) fucosyltransferase encoded in Fuc-TIII gene (Le gene) on chromosome 19. Weak hemagglutination reactions are often observed in the Lewis blood typing to cause false-negative reactions. The level of CA19-9 tumor marker, defined as sialylated Le(a) (sLe(a)), is influenced by the Lewis blood phenotype. The sLe(a) antigen is also considered to play a role in hematogenous metastasis of tumor cells. The accurate genotyping of Fuc-TIII gene would be, therefore, necessary for solving above questions. In addition to the two missense mutations previously reported by us, i.e. the T59G and the G508A, further sequence analyses revealed a new single base substitution, the T1067A, changing the Ile356 to Lys in the catalytic region. Polymerase chain reaction-restriction fragment length polymorphism methods were developed for the detection of these three missense mutations and applied in 15 Lewis negative (le/le) and 65 Lewis positive individuals (Le/Le or Le/le). These methods were found to be useful for genetic diagnosis for the Lewis histo-blood typing. All le alleles had the T59G mutation, whereas none of the Le alleles did. The le alleles were divided in two types, le1, having the G508A mutation, and le2, having the T1067A mutation. The T1067A mutation reduced the enzyme activity less than 10%, whereas the G508A mutation in the catalytic domain made the enzyme completely inactive. The frequency of occurrence of Le, le1, and le2 in the Japanese population by random sampling study was found to be 66, 30, and 4%, respectively.

Alleles↗
PubMed1994

A novel ex vivo method for assaying adhesion of cancer cells to the peritoneum.

A novel ex vivo method to determine the cell adhesion of cancer cells to the peritoneum was described. The wells of a microtiter plate were filled with cell suspension and sealed using mouse peritoneum. The peritoneum was fixed using a plastic cover and the plate was turned upside down and incubated for cell adhesion. After incubation for 80 min, the plate was centrifuged and non-adherent cells were assayed by MTT assay. Human cancer cells (MKN28, MKN45, MKN74, KM12C and KM12SM) adhered to the mouse peritoneum as well as cells from mouse (Colon26) and the ratio of cells attached to the peritoneum was estimated to be between 12.8 and 66.4%. This simple method could be useful to investigate the adhesion molecule associated with peritoneal dissemination.

Animals↗
PubMed1994

The recognition of cancer-associated fucosylated antigens in colorectal cancer by a novel monoclonal antibody, YB-2.

A monoclonal antibody, YB-2, which has a novel epitope for fucosylated antigens and shows cross-reactivity with Y/Leb/H type 2 antigens, was used in an immunohistochemical study of human neoplastic and normal colorectal tissues. Of 64 colorectal cancers, 59 (92.2%) were stained by the YB-2 antibody; however, only 3 (12.0%) of 25 samples of normal colon mucosa and 13 (50.0%) of 26 adenomas expressed the antigens recognized by YB-2. Clinicopathologically, the YB-2-negative colon cancers were exclusively in Dukes stage A. These results indicate that the monoclonal antibody, YB-2, could detect cancer-associated antigens, and the degree of YB-2-reacted antigen expression might be correlated with the progression of colorectal carcinogenesis.

Adenoma↗
PubMed1993

Alpha (1,3/1,4)fucosyltransferase (FucT-III) gene is inactivated by a single amino acid substitution in Lewis histo-blood type negative individuals.

Human alpha (1,3/1,4)fucosyltransferase (FucT-III) genes were cloned from genomic DNAs of seven Lewis negative (Le(a- b-)) individuals. Restriction mapping analyses revealed that an additional Pvu II site was created in the FucT-III genes from Lewis negative individuals. Four of these individuals were shown to be heterozygous for the Pvu II site and three were homozygous for it. The Pvu II site was produced by a single base substitution at the 508 nucleotide of coding sequence, G to A, resulting in the amino acid substitution, Gly to Ser at position 170. Another single base substitution, resulting in the change of Asp to Ala at position 336, was observed in the Lewis negative FucT-III gene which did not have the Pvu II site. The FucT-III enzyme was inactivated by these two mutations resulting in a single amino acid substitution in the catalytic region. All FucT-III genes, regardless of the Pvu II site, from Lewis negative individuals had a single base substitution, the T at position 59 to G, resulting in the change of Leu to Arg at position 20. This mutation, however, was not responsible for FucT-III gene inactivation.

Amino Acid Sequence↗