Search PubMed⌕ Search

Biomedical subjects

A Amemiya

Publications and source records attributed to A Amemiya.

At least 37 records · Page 2Linked to original sources
PubMed1998

A patient-like orthotopic implantation nude mouse model of highly metastatic human ovarian cancer.

Clinically relevant animal models of human cancer are important for studies of cancer biology, invasion and metastasis, and for investigating new forms of prognostic diagnosis and therapy. An ovarian tumor line (RMG-1: human clear cell carcinoma of the ovary) previously grown subcutaneously was implanted orthotopically as intact tissue into the ovarian capsule of 22 nude mice. The tumors showed progressive growth at the orthotopic site in all animals. Tumor-associated serum galactosyltransferase (GAT) tended to be positive in all nude -mice. The tumors invaded or metastasized to the contralateral ovary, retroperitoneum, mesentery and peritoneum, and omentum, and metastasized to the subcutaneous tissue, lymph nodes and distant organs including the liver, kidney, pancreas, and diaphragm. In striking contrast, subcutaneous transplantation of this tumor resulted in growth in only 2 of 5 animals with local lymph node and kidney involvement but no retroperitoneal or peritoneal involvement. These findings suggest that orthotopic implantation provides a suitable micro-environment in which ovarian cancer can express its intrinsic clinically-relevant properties. This approach is relevant to the clinical features of ovarian cancer and is thought to be a useful model for studies of therapy for this cancer.

Adenocarcinoma, Clear Cell↗
PubMed1998

Immunohistochemical analysis of a case of gastritis cystica profunda associated with carcinoma development.

We report a rare case of gastritis cystica profunda (GCP) accompanied by carcinoma that developed in a 51-year-old Japanese man without antecedent gastric surgery. The polypoid tumor was located in the upper body of the resected stomach. Histologically, it was characterized by herniation of surface epithelium and cystic glands in the submucosa, muscularis propria, and subserosa. Marked chronic atrophic gastritis was found throughout the stomach, and dysplastic epithelia and a few adenocarcinoma cells were found in the deeper parts of the GCP. The Ki-67, p53, and p21WAF1/CIP1 labeling indices for the deeper part of the GCP were higher than those for the superficial parts or the surrounding mucosa, suggesting that both epithelial cell proliferation and p53-dependent p21WAF1/CIP1 expression in DNA-damaged cells, which might be associated with gastritis, are enhanced in line with penetration of glands. The underlying mechanisms might be linked in a chain of factors leading to malignancy.

Adenocarcinoma↗
PubMed1998

Selection of human ovarian carcinoma cells with high dissemination potential by repeated passage of the cells in vivo into nude mice, and involvement of Le(x)-determinant in the dissemination potential.

Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Le(x)-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Le(x) antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Le(x), which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Le(x) antibody, indicating Le(x)-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Le(x)-glycolipids, III3Fuc alpha-nLc4Cer and V3Fuc alpha-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Le(x)-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Le(x) is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Le(x) antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Le(x)-determinant and the Le(x)-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.

Adenocarcinoma, Clear Cell↗
PubMed1998

Detection of human papillomavirus type 2 related sequence in oral papilloma.

Oral papilloma is a benign tumourous lesion. Part of this lesion is associated with human papillomavirus (HPV) infection. We analysed the genetical and histopathological evidence for HPV type 2 infection in three oral papillomas. Southern blot hybridization showed HPV 2a sequence in one lesion. Cells of the positive specimen appeared to contain high copy numbers of the viral DNA in an episomal state. In situ staining demonstrated virus capsid antigen in koilocytotic cells and surrounding cells in the hyperplastic epithelial layer. Two other specimens contained no HPV sequences by labeled probe of full length linear HPVs 2a, 6b, 11, 16, 18, 31 and 33 DNA under low stringency hybridization conditions. These results showed the possibility that HPV 2 plays a role in oral papilloma.

Adult↗
PubMed1998

Coexpression of cholesterol sulfate and cytokeratin as tumor markers in well-differentiated squamous cell carcinoma of the human uterine cervix.

The expression of cholesterol sulfate (CS) is known to increase during squamous differentiation of keratinocytes and to activate the epsilon, eta, and zeta forms of protein kinase C as a signal transduction molecule for the subsequent expression of transglutaminase-1 (TG-1) and cytokeratins. To gain further insight into the regulation of cellular differentiation and tumorigenesis by CS, we examined the concentration and the potential for synthesis of CS in seven and four surgical specimens from human ovarian and uterine cervical cancer patients, respectively, and eight cell lines established from human uterine cervical cancer patients and compared them for the rate of expression of cytokeratin. CS was present in all of the uterine cervical cancer tissue specimens but only in the mucinous type of cystadenocarcinoma among ovarian cancer tissue specimens, and cytokeratin was highly expressed in the tissues with a high concentration of CS, which were classified as well-differentiated on the basis of morphological examination. Similarly, cells derived from a keratinizing type of well-differentiated cervical carcinoma demonstrated strong potential for synthesis of CS, stained positive with anti-cytokeratin antibody, and exhibited a higher specific activity of TG-1, whereas the cells without CS did not stain positive with anti-cytokeratin antibody and exhibited a lower specific activity of TG-1. These findings indicate that CS is coexpressed with TG-1 and cytokeratin in the well-differentiated types of squamous cell cancers as a tumor marker.

Biomarkers, Tumor↗
PubMed1997

Detection of melatonin and serotonin N-acetyltransferase and hydroxyindole-O-methyltransferase activities in rat ovary.

Melatonin (N-acetyl-5-methoxytryptamine) and the activities of two melatonin-synthesizing enzymes, serotonin N-acetyltransferase (acetyl coenzyme A: arylalkylamine N-acetyltransferase EC 2.3.1.87; NAT) and hydroxyindole-O-methyltransferase (S-adenosyl-L-methionine: N-acetylserotonin-O-methyltransferase EC 2.1.1.4; HIOMT), were assayed in extracts of ovaries obtained from virgin Wistar-derived rats (7-9 week-old) during the light period of a 12 h light/12 h dark cycle. Melatonin was detected in the rat ovary using reverse-phase high-performance liquid chromatography (HPLC) coupled with fluorometric detection and radioimmunoassay (RIA). In addition, NAT and HIOMT activities were found in rat ovary. The apparent Michaelis constants (Km) for the substrates of NAT and HIOMT in the rat ovary were similar to those reported for the pineal gland and retina. These data suggest that the rat ovary, like the pineal gland and the retina, may synthesize melatonin from serotonin by the sequential action of NAT and HIOMT.

Acetylserotonin O-Methyltransferase↗
PubMed1997

Early bone formation around calcium-ion-implanted titanium inserted into rat tibia.

Rat tibia tissue into which calcium ion (Ca2+)-implanted titanium was surgically placed was histologically analyzed to investigate the performance of the Ca(2+)-implanted titanium as a biomaterial. Calcium ions were implanted into only one side of titanium plates at 10(17) ions/cm2 and the Ca(2+)-treated titanium was surgically implanted into rat tibia for 2, 8, and 18 days. Tetracycline and calcein were used as hard-tissue labels. After excision of the tibia, the tissues were fixed, stained, embedded in polymethyl methacrylate, and sliced. The specimens were observed using a fluorescence microscope. A larger amount of new bone was formed on the Ca(2+)-treated side than on the untreated side, even at 2 days after surgery. In addition, part of the bone made contact with the Ca2(+)-treated surface. On the other hand, bone formation on the untreated side was delayed and the bone did not make contact with the surface. Mature bone with bone marrow formed in 8 days. Neither macrophage nor inflammatory cell infiltration was observed. The results indicated that Ca(2+)-implanted titanium is superior to titanium alone for bone conduction.

Animals↗
PubMed1997

Ovulation induction in a woman with premature ovarian failure resulting from a partial deletion of the X chromosome long arm, 46,X,del(X)(q22).

OBJECTIVE: To report successful ovulation induction in a woman with premature ovarian failure (POF) resulting from a partial Xq deletion. DESIGN: An uncontrolled study. SETTING: University hospital. PATIENT(S): A 27-year-old woman with 46,X,del(X)(q22) who had hypergonadotropic secondary amenorrhea. INTERVENTION(S): Injections of hMG (225 IU/d) for 8 consecutive days after endogenous gonadotropin suppression with a long-acting GnRH agonist (900 micrograms/d) for 12 weeks, together with cyclic sex steroid replacement therapy. MAIN OUTCOME MEASURE(S): Serum concentrations of E2 and P as well as ultrasonography. RESULT(S): Folliculogenesis and ovulation. CONCLUSION(S): Ovulation induction is possible in patients with POF caused by X chromosome aberrations.

Adult↗
PubMed1997

The prognosis of fetuses with a shortened femur and humerus length before 20 weeks of gestation.

OBJECTIVE: The purpose of this study was to evaluate the prognosis of fetuses with a shortened femur and humerus length detected at earlier than 20 weeks of gestation. METHODS: The study population consisted of 549 Japanese pregnant women. The prognosis of the shortened femur and humerus length fetuses was evaluated and the predictivity of the shortened femur and humerus length for chromosomal abnormalities and structural malformations was also calculated. RESULTS: All seven shortened femur and humerus length fetuses had some kind of structural malformations and three fetuses also had chromosomal abnormalities. The detection rate, positive predictive value and false positive rate for structural malformations were 17.9%, 100% and 0%, respectively. The positive predictive value for chromosomal abnormalities was 43%. CONCLUSION: The shortened femur and humerus length fetuses in Japanese women demonstrated an increased risk of structural malformations, especially in the cardiovascular system, as well as chromosomal abnormalities.

Adult↗
PubMed1997

Osteogenesis by bone marrow stromal cells maintained on type I collagen matrix gels in vivo.

In this study, we demonstrated that bone marrow stromal cells maintained on type I collagen matrix induced bone in vivo. The formed bone contained bone marrow, and the process of bone formation occurred without cartilage formation. Bone marrow stromal cells differentiated into osteoblasts on type I collagen matrix in vitro, but types II, III, and V collagens did not possess this activity. These findings imply that type I collagen matrix offers a suitable environment for the induction of osteoblastic differentiation in vitro and osteogenesis in vivo.

Alkaline Phosphatase↗
PubMed1997

Salivary gland scintigraphy with 99mTc-pertechnetate in Sjögren's syndrome: relationship to clinicopathologic features of salivary and lacrimal glands.

Salivary gland scintigraphy was performed on 52 patients who were suspected of having Sjögren's syndrome (SS), and the results were compared with clinicopathologic features of the salivary and lacrimal glands. The time-activity curves which were obtained from computer-assisted analysis of 99mTc-pertechnetate (99mTc) scintigraphy were classified into four types (normal, median, flat and sloped types). The stimulated parotid flow rate decreased and the incidence of SS-related sialographic and histopathologic findings increased significantly as the scintigraphic abnormality advanced. In addition, the lacrimal gland function decreased and the proportion of patients diagnosed as having keratoconjunctivitis sicca (KCS) increased significantly as the scintigraphic abnormality advanced. These results indicate that the results of scintigraphy are related not only to the clinicopathologic features of the salivary glands but also to the lacrimal gland function in SS.

Chi-Square Distribution↗
PubMed1997

Comparison between submucosal (extra-nodal) and nodal non-Hodgkin's lymphoma (NHL) in the oral and maxillofacial region.

Fifty-two cases of non-Hodgkin's lymphoma (NHL) in the oral and maxillofacial region, comprising 31 submucosal (extra-nodal) and 21 cervical node NHLs, were investigated. The patients' ages ranged from 5 to 86 years, with a bimodal age distribution among young people below 12 years of age (average 8 years) and in those aged 30 years or older (average 60.3 years). The male-to-female gender difference ratio was 1.3:1. Patients presented with swelling as the major symptom. Histologically, diffuse, large cell malignant lymphoma was the most frequent type and 67.9% of lymphomas were of intermediate malignancy as defined by the Working Formulation for Clinical Usage. All submucosal lymphomas showed diffuse proliferation patterns, although follicular proliferation was identified in 5 of the 21 nodal lymphomas. Immunohistochemistry showed that the B-cell type was predominant, especially in nodal lymphomas.

Adolescent↗
PubMed1997

The prognosis of fetuses with transient nuchal translucency in the first and early second trimester.

OBJECTIVE: The purpose of this study was to evaluate the prognosis of fetuses with transient nuchal translucency before 15 weeks of gestation. STUDY DESIGN: A nuchal translucency's measurement of > or = 5 mm was considered abnormal. In the period from 1994 to 1995, twelve fetuses were diagnosed at our institution with nuchal translucency. The fetuses all underwent karyotyping and a complete ultrasonographic search for any associated anomalies and a resolution of nuchal translucency at 1-2 week gestational age intervals. RESULTS: Five cases ('Transient NT') demonstrated transient nuchal translucency. Seven cases ('Persistent NT') demonstrated persistent nuchal translucency. The 984 cases with no or less than 5 mm of nuchal translucency (control group) gave birth at the same time. The mean initial week of diagnosis was 12.0 +/- 1.6 weeks in 'Transient NT', and 13.6 +/- 1.8 weeks in 'Persistent NT'. The mean maternal age was 30.8 +/- 6.3 years old in 'Transient NT', 28.9 +/- 3.0 years old in 'Persistent NT', and 30.5 +/- 43 years old in the control group. Abnormal karyotypes were detected in one case in 'Transient NT', and in four cases in 'Persistent NT'. Structural malformations were detected in two cases (40%) in 'Transient NT', seven cases (100%) in 'Persistent NT', and 30 cases (3.0%) in the control group. CONCLUSIONS: Regardless of the spontaneous resolution of abnormal nuchal translucency, there was a high association with both karyotypical and structural abnormalities, and the prognosis of such cases was generally poor, especially persistent NT's prognosis.

Adult↗
PubMed1997

[Prolonged neuromuscular blockade with vecuronium in patient with triple pregnancy treated with magnesium sulfate].

A 33 year-old parturient with triplet pregnancy underwent emergency cesarean section at 35 week of gestation under general anesthesia. The patient had received magnesium sulfate to prevent uterine contraction immediately before the cesarean section. Although serum magnesium value was not beyond therapeutic levels (3.3 mEq.l-1), the neuromuscular blocking effects with vecronium were strengthened. It was not likely that volatile anesthetic enhanced neuromuscular blockade produced by vecuronium because the onset time of vecuronium had already been faster than that in pregnant patients untreated with magnesium before she was exposed to isoflurane. In addition, it is possible that magnesium could interfere with postpartum uterine contractions because of its tocolytic properties. Magnesium sulfate therapy has several implications to anesthetic agents. We, anesthesiologists, should know about the biophysiological effects of magnesium and control the interaction between anesthetic agents and this electrolyte.

Adult↗
PubMed1997

Identification of human papilloma virus DNA sequence in the hyperplastic epithelium of an oral denture fibroma.

The human papilloma virus (HPV) associated with hyperplastic epithelium in an oral denture fibroma was examined by southern blot hybridization. Extracted DNA was hybridized with full length linear HPV type 2a, 6b, 11, 16, 18, 31 and 33 DNAs as a mixed probe only under low stringent conditions. The hybridized bands digested with Bam HI and Eco RI were approximately 8.8 kbp and 15 kbp, respectively. Thus the lesional HPV DNA was different from HPV types used as probes and was probably integrated into host cell chromosomal DNA judging by the off-size high molecular weight bands. Considering the contaminating mesenchymal region and uninfected epithelial cells as well as the evidently limited homology with probe HPV DNAs, the virus copy number in infected cells was poorly defined. In situ antigen staining signals were widely detected in the hyperplastic epithelial layer.

Blotting, Southern↗
PubMed1997

Antisense E1AF transfection restrains oral cancer invasion by reducing matrix metalloproteinase activities.

E1AF is a newly identified human ets-family transcription factor. We have reported that E1AF can up-regulate transcription of matrix metalloproteinase (MMP) genes and confers invasive phenotype on human cancer cells. HSC3 is an oral squamous-cell-carcinoma-derived cell line, and it manifests high levels of E1AF and MMP-1 and -9 gene expression that are associated with invasive potential. We reconstructed an E1AF antisense expression vector, transfected HSC3 cells with the vector, and obtained HSC3AS cells that express E1AF antisense RNA. HSC3AS showed decreasing mRNA and protein levels of MMP-1, -3, and -9. Moreover, HSC3AS showed lower invasive potential in vitro three-dimensional raft culture and in vivo implantation into nude mice. These results imply that transfection of antisense E1AF inhibits tumor invasion by down-regulating MMP genes.

Adenovirus E1A Proteins↗
PubMed1996

High-risk HPV-positive human cancer cell lines show different sensitivity to cisplatin-induced apoptosis correlated with the p21Waf1/Cip1 level.

We investigated the sensitivity and cell-cycle inhibitory gene expression of human papillomavirus (HPV) 16- and 18-positive human cancer cell lines after DNA damage induced by treatment with the anti-cancer drug cisplatin. Four HPV-positive cell lines (Caski, SiHa, HeLa and KB) were treated with cisplatin at various concentrations. Apoptotic cell death was observed in a dose-dependent manner in all cell lines treated with cisplatin; however, colony assay for chemosensitivity revealed that HeLa and KB cells (HPV 18-positive cell lines) were more sensitive than SiHa and Caski cells (HPV 16-positive cell lines). Northern blot analyses showed that p53 and p21Waf1/Cip1 mRNA were detectable in all untreated cells, and increasing amounts of these transcripts were identified in all cell lines treated with cisplatin. However, signals were more prominent in HeLa and KB, HPV 18-positive-cells. Immunohistochemical detection of p21Waf1/Cip1 protein showed that the p21-positive cells with apoptotic features were more distinct in KB and HeLa cells (HPV 18-positive) than in SiHa and Caski cells (HPV 16-positive). Our results show that there were differences in sensitivity to cisplatin among four types of high risk HPV-positive cells, possibly due to different levels of p21Waf1/Cip1 up-regulation by functional p53.

Apoptosis↗