Biomedical subjects

H Nakazato

Publications and source records attributed to H Nakazato.

At least 19 recordsLinked to original sources

PubMed1996

Prognostic value of preoperative immunosuppressive acidic protein in patients with gastric carcinoma. Findings from three independent clinical trials. Tumor Marker Committee for the Study Group of Immunochemotherapy with PSK for Gastric Cancer.

BACKGROUND: Immunosuppressive acidic protein (IAP) has been reported to have close correlation with the impairment of host immune response. To evaluate the significance of IAP in clinical studies, the prognostic value of preoperative IAP was investigated in clinical trials of patients with gastric carcinoma after curative resection. METHODS: An appropriate IAP threshold value of 580 micrograms/mL was determined using Cox's proportional hazards model. Five-year survival rates were estimated for high and low IAP groups in three different clinical studies. Meta-analysis was performed based on individual patient data, and summarized hazard ratios were estimated using a stratified proportional hazards model. RESULTS: Meta-analysis of the three clinical trials demonstrated that patients with preoperative IAP levels above the threshold had significantly poorer cancer related survival (P = 0.0039) and absolute survival (P = 0.0023), even after adjustment for the major prognostic factors. CONCLUSIONS: Gastric carcinoma patients with an IAP value above the threshold level of 580 micrograms/mL have a higher risk of cancer death and absolute death than patients with an IAP value below the threshold value.

Adult↗

PubMed1996

Human placental leucine aminopeptidase/oxytocinase. A new member of type II membrane-spanning zinc metallopeptidase family.

The serum level of placental leucine aminopeptidase (P-LAP) increases during pregnancy. P-LAP degrades several peptide hormones such as oxytocin and vasopresin, suggesting a role in maintaining homeostasis during pregnancy. In the study reported here, we have isolated a cDNA clone with 4084 base pairs encoding P-LAP from a human placental cDNA library. The amino acid sequence deduced from the cDNA contained all of the sequences of the peptide fragments obtained by digestion of the purified protein with trypsin. The predicted P-LAP contains the HEXXH consensus sequence of zinc metallopeptidases, indicating that the enzyme belongs to this family, which includes aminopeptidase N and aminopeptidase A. The deduced sequence also contains a hydrophobic region near the N terminus, suggesting that the enzyme is a type II integral membrane protein. Northern blot analysis revealed that P-LAP was expressed in several tissues, some of which expressed two forms of mRNAs. These results suggest that the enzyme is synthesized as an integral membrane protein and is released into blood under some physiological conditions.

Amino Acid Sequence↗

PubMed1996

[Quality control of surgery in multicenter study--interinstitutional and individual differences].

UNLABELLED: In a prospective randomized controlled trial (PRCT) of adjuvant chemotherapy for gastric cancer patients participated by 6 cancer center hospitals, inter-institutional and inter-individual differences about several factors related to the surgery and remote survivals were analyzed. From 1988 to 1992, 1,049 evaluable patients were enrolled and stratified to 6 groups according to the grade of the serosal invasion and curability, and analyzed statistically. RESULTS: 1) There were no inter-institutional differences about postoperative survival rate, but there were slight differences about patient's background factors and entry policy of each institution. 2) There were no inter-institutional differences about several factors related to the surgery such as operative time, bleeding volume during operation, and the length of the administration periods. 3) There were no inter-individual differences about the length of the administration periods, but there were a little differences about operative time and the volume of hemorrhage. When the PRCT of adjuvant chemotherapy of which the end point is survival would be designed, no inter-institutional differences about remote survival and surgical operation in each institution should be confirmed before starting the trial.

Chemotherapy, Adjuvant↗

PubMed1995

Initiating and responsible enzyme of arginine vasopressin degradation in human placenta and pregnancy serum.

The hydrolysis of arginine vasopressin (AVP) by human placental subcellular fractions and pregnancy sera was studied in the presence of selective inhibitors and the antibody against pregnancy serum oxytocinase (P-LAP) (EC 3.4.11.3) by measuring liberated amino acids by high-performance liquid chromatography (HPLC). AVP degradation by placental subcellular fractions and pregnancy sera was inhibited by bestatin. The IC50 values of bestatin on AVP degradation by placental subcellular fractions and pregnancy sera were similar to that of this inhibitor on the P-LAP measured by L-Leu-p-nitroamnilide as a substrate (LAP activity), which we reported previously. Our immunotitration study clearly showed that the initiating and responsible protease in AVP degradation in human placenta and pregnancy serum is P-LAP. Since N-benzylcarbonyl-valyl-prolinal (Z-Val-prolinal), a selective inhibitor of post-proline endopeptidase, and phosphoramidon, a putative endopeptidase-24.11 inhibitor, could not significantly influence the degradation of AVP by placental microsomal fractions. Neither enzyme seems to be actively involved in AVP degradation.

Amino Acid Sequence↗

PubMed1995

Receptor-linked antigen delivery system. Importance of autologous alpha 2-macroglobulin in the development of peptide vaccine.

We have hijacked a process of the receptor-mediated endocytosis to transport peptide antigens into antigen presenting cells (APCs) for the purpose of increasing the level of antigen presentation (named Receptor-Linked Antigen Delivery System (R-LADS)). By coupling an endogenous plasma proteinase inhibitor alpha 2-macroglobulin (alpha 2M) to a synthetic peptide having a partial sequence of HIV-1 envelope protein, alpha 2M was made to carry the peptide into APCs as a part of the normal alpha 2M cycle, which resulted in an increased production of specific antibodies against the peptide (Mitsuda, S., Nakagawa, T., Osada, T., Shimamoto, T., Nakazato, H. and Ikai, A. (1993) Biochem. Biophys. Res. Commun. 194, 1155-1160). We demonstrate here that this procedure becomes a more efficient tool for antibody production when autologous transporter protein was used. By using murine alpha 2M (m alpha 2M) instead of heterologous human alpha 2M (h alpha 2M) when mice were experimental animals, we were able to dramatically enhance the production level of anti-HIV-1 peptide antibodies and shorten the period which is needed for antibody production. We aim to develop effective peptide vaccines by further improving this system.

3T3 Cells↗

PubMed1995

The effect of transfection of the CEA gene on the metastatic behavior of the human colorectal cancer cell line MIP-101.

Carcinoembryonic antigen (CEA) has been shown to increase the metastatic potential of some human colorectal cancer cell lines. To investigate further the mechanisms involved we have produced three clones (6, 8 and 17) from the poorly differentiated human colorectal cancer cell line MIP-101 that have been transfected with the full length cDNA encoding for human carcinoembryonic antigen (CEA). They produce CEA with a mol. wt. of 180000 by Western blotting and secrete it into the culture medium. Clone 6 is a high CEA producer, clones 8 and 17 are intermediate producers. The doubling time for clone 8 was similar to that of the parent cell line while clones 6 and 17 had doubling times nearly twice that of the parent cells. These clones are tumorigenic when injected subcutaneously in nude mice are positive for CEA by immunoperoxidase staining and the mice have elevated blood levels of CEA. Clone 6 formed large aggregates in culture while clone 17 formed smaller aggregates. Clone 8 behaved like the parent cell line with rare cell/cell contact. Clones 6 and 17 also adhered to CEA coated plastic while clone 8, a neo-transfected control and the parent cell line did not. A significant increase in the incidence of hepatic tumors was observed with clone 6 (P < 0.01) and clone 17 (P < 0.02) following intrasplenic injection into nude mice. Immunohistopathology of the hepatic tumors showed strong CEA staining from clones 6 and 17 with weak staining from clone 8. The parent cell line was negative for CEA as were the neo-transfected controls. Of the neo controls none of 10 had liver colonies. Mice injected with clone 6 which developed liver metastasis had the highest plasma levels of CEA (37.3 +/- 8.8 ng/ml). We observed strong CEA staining in Kupffer cells in the normal liver adjacent to the CEA producing tumors. This study provides further evidence for the involvement of CEA in the metastatic process.

Adenocarcinoma↗

PubMed1995

Randomized study with mitomycin C + 5-fluorouracil+cytosine arabinoside (MFC)+5-fluorouracil, MFC+tegafur and uracil (UFT), and MF+UFT in advanced gastric cancer: interinstitutional differences in a multicenter study in Japan.

In a phase III randomized trial of adjuvant chemotherapy for gastric cancer, interinstitutional differences were analyzed. A trial of three regimens: mitomycin C, 5-fluorouracil(5-FU) and CA (MFC) + continuous oral 5-FU (Group C); MFC + continuous oral UFT(tegafur and uracil) (Group B); and MF + UFT (Group C) after operation was conducted in 466 patients with gastric cancer (stage II and III) at four hospitals in Japan (CIH, CAD, ACC and NCC). Patients were stratified by the institution, stage, and tumor size (8 cm ><). The 5-year survival rates were in the order of Group A (79.0%) > B (70.0%) > C (61.0%) (P = 0.1228) in total, A (95.0%) > B (80.0%) > C (58.0%) (P < 0.05) at CAD (82 patients), A > C > B at CIH (215), C > A > B at ACC (95), and B > A > C at NCC (78). The survival rate of patients with S2(serosal exposure), 8 cm < and N0-1 cancer was higher at CIH than at the other institutions. The interinstitutional differences in patient characteristics and surgical technique were more powerful than the differences among the three groups.

Administration, Oral↗

PubMed1995

Epitope mapping of monoclonal antibodies to tumor necrosis factor-alpha by synthetic peptide approach.

A monoclonal antibody (mAb) against human tumor necrosis factor-alpha (TNF-alpha), designated 3B10, neutralizes biological activity of TNF-alpha, while another anti-TNF-alpha mAb 10F10 does not. In Western blot analysis, both mAbs bound to SDS-denatured TNF-alpha, indicating that the epitopes recognized by the mAbs are sequential but not conformational. To map precisely the epitopes of the mAbs, 76 overlapping octapeptides corresponding to an entire sequence of TNF-alpha were synthesized and their abilities to react with the mAbs were examined by enzyme-linked immunosorbent assay (ELISA). 3B10 bound to only one peptide at position 81-88 of TNF-alpha, SRIAVSYQ, whereas 10F10 was reactive with three overlapping peptides, ANALLANG (33-40), ALLANGVE (35-42), and LANGVELR (37-44). These results demonstrate that the 81-88 and 37-40 regions are important for the recognition of TNF-alpha by 3B10 and by 10F10, respectively. In solid-phase ELISA, 3B10 inhibited the binding of TNF-alpha to soluble TNF receptors, sTNF-RI and sTNF-RII. In contrast, 10F10 exerted little effect on the binding. TNF-alpha was detected by sandwich-type ELISA where 3B10 alone was used for both capture and detection, suggesting that 3B10 did not interfere with the trimer formation of TNF-alpha. The results obtained in this study suggest that the 81-88 region of TNF-alpha may participate in the receptor binding and that 3B10 neutralizes the activities of TNF-alpha by blocking the region.

Amino Acid Sequence↗

PubMed1995

Splicing mutations in the COL4A5 gene in Alport's syndrome: different mRNA expression between leukocytes and fibroblasts.

The COL4A5 gene from 40 patients with Alport's syndrome was examined using single-strand conformation substitution at the acceptor site (-2) of intron 50 and a G-to-C substitution at the donor site (+1) of intron 47, respectively. The transcript in peripheral leukocytes from the former had a 10-nucleotide deletion. This shortened transcript was derived from abnormal splicing in a cryptic acceptor site within exon 51. This could be translated into a protein with an alteration of three amino acids followed by premature termination, which eliminated 23 amino acids from the carboxyl end. Gene tracking revealed that the mother and a brother carried the mutant allele. In the latter, the transcript in leukocytes was normal, but that in cultured skin fibroblasts showed skipping of exon 47, the result being that 71 amino acids were absent. Glomerular basement membrane from the patient did not react with the anti-alpha 5(IV) antibody. His maternal grandmother, mother, and a sister, all with abnormal urinalysis, carried the mutant allele. Thus, the appearance of exons of the COL4A5 gene in leukocytes may differ from that in fibroblasts. If kidney mRNA is not available, mRNAs from cultured skin fibroblasts, in addition to leukocytes, can be used for gene analysis in subjects with Alport's syndrome.

Adolescent↗

PubMed1995

A reference of the GOLD classification of monoclonal antibodies against carcinoembryonic antigen to the domain structure of the carcinoembryonic antigen molecule.

The epitopes of 42 well-characterized monoclonal antibodies (MAbs) against carcinoembryonic antigen (CEA) from 10 different research groups were mapped in terms of domain structure (domains N, A1-B1, A2-B2, and A3-B3) of the CEA molecule on the basis of the reactivities with recombinant CEA proteins expressed in Chinese hamster ovary cells. Thirty-six of the 42 MAbs tested have previously been classified into 5 essentially nonoverlapping epitope groups (GOLD 1-5) by cross-competition assays among MAbs for CEA binding (Hammarström S, et al.: Cancer Res. 1989; 49:4852-4858). The epitopes recognized by GOLD 2 MAbs were all present on domain A2-B2, those for GOLD 5 MAbs were all on domain N, and those for GOLD 4 were mapped around domains A1-B1 and A2-B2. On the other hand, the epitopes for GOLD 1 MAbs were distributed into domains N, A2-B2, and A3-B3, and those for GOLD 3 MAbs were separated into domains N and A3-B3. Although the exact reasons for the dispersed patterns of GOLD 1 and 3 MAbs on the domain structure of the CEA molecule are unclear at present, several factors, such as a spatial relation or a close proximity of epitopes, conformation dependency, and repetitivity of epitopes, may be considered as possible explanations. The epitope mapping reported here helps form the basis for understanding the relation between the chemical structure and antigenic activities of the CEA molecule and may be useful to study the functions of the CEA molecule, especially those of the respective domains.

Animals↗

PubMed1995

A novel proteinase, glucagon-degrading enzyme, secreted by a human pancreatic cancer cell line, HPC-YO.

Sixty-four kinds of cell lines were examined as to their ability to degrade glucagon using conditioned-media obtained from their protein-free cultures. Two human tumor cell lines were shown to produce this activity, and the cell line, HPC-YO, established from a human pancreatic carcinoma was shown to produce the highest level of activity. The glucagon-degrading enzyme (GDE) was purified from HPC-YO conditioned-medium by a combination of ion-exchange, gel filtration, and hydroxylapatite column chromatographies. The purified GDE also degraded vasoactive intestinal polypeptide (VIP) and secretin, however, it did not cleave EGF, gastrin, insulin, somatostatin, substance P, neurotensin, or growth hormone. The molecular weight of GDE is 83,000, as determined on SDS-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence of GDE was blocked, and the five partial amino acid sequences obtained on lysyl-endopeptidase digestion were determined to be N-L-T-E-E-Y-D-V-S-D-G-E-I-E-L-L-Y-E-K, V-E-T-Y-Y-D-L-L-F-E-K, L-Y-W-F-L-D-E-A-K, S-N-S-T-S-Y-V-K, and Y-Y-A-S-T-S-Y-D-D-T-Y-K. The same or homologous amino acid sequences have not been found in known proteins, demonstrating that GDE is a novel peptidase that degrades the secretin family: glucagon, VIP, and secretin.

Amino Acid Sequence↗

PubMed1995

Persistence of chronic mood disorders: a 2 year follow-up.

Chronic mood disorder patients who remain frequent and long-term users of psychiatric facilities constitute a major clinical concern today. A 2 year naturalistic prospective follow-up study was conducted on a cohort (n = 40) randomly extracted out of 335 such patients. Longitudinal data involving semi-structured interviews, observer-rated scales and self-report measures were available for 37 patients (93%). While three (8%) remitted completely, the cohort on the average showed no statistically significant change in the severity of depression, social adjustment or global functions during the 2 years under observation. Two baseline features that characterized ameliorated patients were the absence of panic disorder and lower level of education.

Adult↗

PubMed1995

Predictive validity of subtypes of chronic affective disorders derived by cluster analysis.

This study aimed to examine the predictive validity of the cluster-analytically derived 3 subtypes of chronic affective disorders that were proposed on the basis of cross-sectional symptoms and were shown to have some external validity with regard to psychosocial characteristics. Two-year naturalistic follow-up data were available for 38 (97%) of the original 39 patients with chronic affective disorders. The 3 subtypes, which were named psychotic subtype, late-onset female subtype and depressive personality subtype in the previous analyses, did not differ in their depressive severity or social functioning upon entry. In the course of the 2-year follow-up, however, there were significant differences in the Global Assessment of Functioning scores as well as the social adaptation in the economic sphere according to the Social Adjustment Scale-Self Report. All these indices revealed the psychotic subtype to have the worst outcome, followed by the depressive personality subtype, and the late-onset female subtype fared best.

Adult↗

PubMed1995

Immunochemical analysis of carcinoembryonic antigen (CEA)-related antigens differentially localized in intracellular granules of human neutrophils.

Subcellular localization and antigenic properties of eight carcinoembryonic antigen (CEA)-related proteins (nonspecific cross-reacting antigens, NCAs) in neutrophils, including CD66 antigens, were examined with a panel of CD66 monoclonal antibodies (MAbs), whose specificities were characterized with CHO cells expressing CEA gene family recombinant proteins. Intracellular granules of neutrophils were isolated by cell lysis followed by centrifugation on a sucrose gradient. SDS-PAGE analysis of immunoprecipitates from the granules revealed that NCA-95 (CD66c, NCA-50/90) exists predominantly in the azurophil granule-enriched fraction. NCA-90 was identified in the same fraction and was suggested to be a molecule closely-related to NCA-95. NCA-26 was identified in the specific granule fraction together with NCA-160 (CD66a, BGP), and was likely a splicing variant of NCA-160. NCA-100 (CD66b, CGM6) was also identified in this fraction. NCA-80, -58 and -30, which are detectable in culture medium of neutrophils with polyclonal anti-NCA-50/90, were not recognized by any of the CD66 MAbs tested. These findings indicate that NCA-160, -100, -95, -90 and -26 are the products of the CEA gene family and stored separately in azurophil and specific granules. It remains to be clarified whether or not the other three secretory antigens, NCA-80, -58 and -30, are still unknown members of the CEA family.

Animals↗

PubMed1995

[2'-5' olygoadenylate synthetase activity in peripheral facial paralysis].

Interferons are produced in response to viral infection and play an important part in defense by their antiviral effects. An interferon-induced enzyme, 2'-5' oligoadenylate synthetase (2-5AS) also takes an important part of the system of defense against viral infections, and its activity elevates in nonspecific viral infections. This study was designed to evaluate the usefulness of examining serum 2-5AS activity and peripheral blood WBC 2-5AS (WBC 2-5AS) as diagnostic aids of viral infections that cause facial paralysis. Samples were obtained from 83 patients with Bell's palsy, 20 with Ramsay Hunt syndrome, 74 healthy individuals, and a total of 177 subjects. In 177, we measured serum 2-5AS level in 123 subjects, WBC 2-5AS level in 57, and both in 25. Serum 2-5AS levels in Bell's palsy (60 cases) ranged from 20 to 146 pmol/dl (average: 38.5). The range in Ramsay Hunt syndrome (13) was 20-333 (average: 59.0), and in healthy controls (50), it was 20-128 (average: 41.4). WBC 2-5AS level ranged from 20 to 5900 pmol/dl (average: 733.2) in Bell's palsy (23 cases), from 20-4540 (average: 1371.4) in Ramsay Hunt syndrome (7), and from 20-903 (average: 294.5) in healthy individuals (24). There were no statistically significant differences in serum 2-5AS activities. Otherwise, there was significant difference (p < 0.01) between healthy individuals and Patients with Ramsay Hunt syndrome in WBC 2-5AS activity. In Bell's palsy, 3 cases (13.0%) with markedly high WBC 2-5AS levels existed.(ABSTRACT TRUNCATED AT 250 WORDS)

2',5'-Oligoadenylate Synthetase↗

PubMed1995

[Clinical study on 78 cases of testicular tumor].

Seventy eight patients with testicular tumor were treated in our hospital between 1982 and 1992. Of 78 patients, 74 had germinal cell tumor (seminoma in 47 patients and non-seminoma in 27), and the other 4 had 3 malignant lymphoma and 1 rhabdomyosarcoma. Ages ranged from 1 to 67 years with the average of 36.1. The age of the patients with seminoma was significantly higher than that of patients with non-seminoma. Most patients complained of painless swelling of the scrotal content, but some patients complained of testicular pain, fever, and so on. Those who complained of such symptoms had significantly worse prognosis than those who had only painless scrotal swelling. Patients with non-seminoma visited us about 4.9 months after the onset of their symptoms and 12.1 months in seminoma. Clinical stages were more progressive in non-seminoma than in seminoma. Inguinal orchiectomy was performed followed by irradiation, chemotherapy, retroperitoneal lymph node dissection or thoracotomy. Recurrence developed in 6 patients and the other 7 patients died of progressive disease within 2 years from the first attendance. The 2-year survival rate calculated by the Kaplan-Meier method was 81 and 70% in seminoma and non-seminoma, respectively, and 100, 88, 63, 75, and 22% in stage I, IIA, IIB, IIIO and IIIA, B, C, respectively.

Adult↗

PubMed1994

Non-proteolytic release of carcinoembryonic antigen from normal human colonic epithelial cells cultured in collagen gel.

Recent studies have shown that, even with a minimal content of carcinoembryonic antigen (CEA), normal human colonic epithelial cells express substantial amounts of CEA mRNA and colonic mucosal fragments cultured in vitro produce CEA quite actively, indicating that CEA should no longer be considered to be of an oncofetal nature. To understand the basis of the usefulness of CEA as a tumor marker, we analyzed the release of CEA, a glycosyl-phosphatidylinositol (GPI)-anchored protein, from colonic epithelial cells, by culturing isolated colonic crypts in collagen gel. The crypts appeared to preserve their morphological and biochemical integrity in the gel for at least 16 hr, and released CEA spontaneously. Three forms of CEA--spontaneously released CEA, CEA liberated with phosphatidylinositol-specific phospholipase C (PI-PLC) and CEA in cell lysates--were indistinguishable on SDS-PAGE. This is in contrast to recombinant CEA spontaneously released from CHO transfectants, which showed a smaller molecular mass than that of PI-PLC-cleaved recombinant CEA. By phase separation using Triton X-114, CEA in the cell lysates of crypts was separated mostly into the detergent phase, while the spontaneously released and the PI-PLC-cleaved CEA were separated into the aqueous phase. When the cells were metabolically labeled with the precursors of the GPI-anchor, 3H-ethanolamine but not 3H-palmitic acid was found in the spontaneously released CEA. These findings suggest that, in contrast to the proteolysis-like release of the recombinant CEA from CHO cells, CEA in normal colonic epithelial cells is released by a non-proteolytic cleavage, which probably occurs through the action of some endogenous phospholipase.

Animals↗

PubMed1994

Metastatic potential in nude mice of Chinese hamster ovary cells expressing human carcinoembryonic antigen.

The role of carcinoembryonic antigen (CEA) in metastasis was examined using Chinese hamster ovary (CHO) cells which had been transfected with cDNA encoding CEA. When 2 x 10(6) cells of a clone of CEA-expressing transfectants, designated CHO/CEA, were injected intrasplenically into athymic nude mice, 8 out of 8 mice developed liver metastases. In contrast, a vector-transfectant C5 did not at all form metastasis in the assay (0 of 8). There was no difference in growth rate between CHO/CEA and C5 in vivo as well as in vitro. MoAbs to N-domain of CEA markedly inhibited the liver metastasis of CHO/CEA cells, while a MoAb to domain III of the antigen did not. These findings suggest that CEA may play an important role in hepatic metastasis, and that the N-domain of CEA molecule contributes to the function of CEA in metastasis.

Animals↗