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S Sekiya

Publications and source records attributed to S Sekiya.

At least 19 recordsLinked to original sources

Impact of maintenance chemotherapy on disease-free survival in patients with stage Ic and II epithelial ovarian cancer.

PURPOSE OF INVESTIGATION: To evaluate the impact on disease free survival (DFS) with maintenance chemotherapy following complete surgery and adjuvant chemotherapy in patients with stage Ic and II epithelial ovarian cancer by a retrospective study. METHODS: One hundred and forty patients with stage Ic and stage II epithelial ovarian cancer were classified into three groups according to the modality of maintenance chemotherapy (no therapy, oral or intravenous administration of anti-cancer drugs). DFS was compared among the three groups, and independent predictive factors for relapse were analyzed. RESULTS: There were no statistically significant differences in DFS among the three groups for either stage Ic or II cancers, stage Ic and stage II. Multivariate analysis revealed that independent predictive factors for relapse were stage II (p = 0.004) in all patients and less than three cycles of adjuvant chemotherapy in stage II patients (p = 0.015). CONCLUSION: Maintenance chemotherapy had no impact on DFS in patients with stage Ic or II epithelial ovarian cancer.

Adenocarcinoma, Clear Cell↗

Hypermutable change of human UV(r)-1 cells by p53 overexpression.

The p53 protein has been reported to regulate cellular responses to genetic stress such as far-ultraviolet light (UV), protecting human cells from mutation. Levels of p53 protein in hypermutable RSa cells were found here to increase soon after UV irradiation, while those in UV(r)-1 cells, a hypomutable variant of RSa cells, showed a delayed increase. Three cell lines overexpressing wild-type p53 in UV(r)-1 cells exhibited higher sensitivity to UV mutagenicity than did control U-V-7 cells transfected with vector alone, assessed using the ouabain-resistance phenotypic mutation test and identification of K-ras codon 12 base substitution mutation. On the other hand, U-V-7 cells showed UV-induced elevation of antipain-sensitive protease activity, but p53 transfectants did not. Moreover, antipain treatment to U-V-7 cells was increased susceptibility to UV mutagenicity. Thus, p53 protein overproduction may sensitize human cells, at least those tested, to UV mutagenicity, in association with inhibition of protease activity.

Cell Division↗

Analysis of E6 variants of human papillomavirus type 33, 52 and 58 in Japanese women with cervical intraepithelial neoplasia/cervical cancer in relation to their oncogenic potential.

The variation of the E6 region of human papillomavirus type 16 (HPV16) is associated with a high risk for cervical carcinogenesis. To see whether the same is the case with HPV33, 52 and 58, known to have high homology with HPV16, we analyzed the E6 sequence variation of these HPVs in 107 Japanese women with cervical intraepithelial neoplasia (CIN) or invasive cervical cancer (ICC): 20 HPV33-positive, 46 HPV52-positive and 41 HPV58-positive cases. HPV33 variants were more frequently observed in CINs I/II than in CIN III/ICCs (71% (5/7) versus 15% (2/13), P=0.02). In HPV52-positive cases, a single E6 variant was detected in 98% of the cases, whereas the prototype accounted for 98% of HPV58-positive cases. In summary, the distribution of E6 variants is different among HPV types tested, suggesting a link between E6 variation and oncogenic potential being type-specific.

Female↗

Significance of perivascular lymphocytic infiltrates in endometrial carcinoma.

BACKGROUND: The objective of this study was to clarify the significance of perivascular lymphocytic infiltrates (PLI) in endometrial carcinoma. METHODS: The pathologic records of 127 patients with endometrioid type adenocarcinoma confined to the uterus were reviewed retrospectively. The patients were divided into 4 groups based on the presence or absence of vascular invasion (VI) and PLI: VI-PLI- (n = 87), VI-PLI+ (n = 7), VI+PLI+ (n = 22), and VI+PLI- (n = 11). Pathologic features including tumor grade, myometrial invasion, cervical involvement, vascular invasion-associated changes (VIAC; VI and/or PLI), tumor size, ovarian metastasis, and pelvic lymph node metastasis were assessed statistically. RESULTS: Selective pelvic lymphadenectomy was performed in 108 patients, and metastasis was identified in 6 cases (5.6%). Lymph node metastasis was the only independent variable related to recurrence (Cox regression analysis, P = 0.0008). Perivascular lymphocytic infiltrates correlated closely with VI (Fisher exact test, P < 0.0001). Vascular invasion-associated changes was the best predictor of lymph node metastasis (logistic regression analysis, P = 0.039), but among the three categories of VIAC, only the VI+PLI- group was significantly associated with lymph node metastasis (P = 0.0045). The odds ratios of VI+PLI- and VI+PLI+ cases for lymph node metastasis were 64.54 and 3.24, respectively. CONCLUSIONS: Although VIAC is the best predictor of lymph node metastasis, the presence of PLI is associated with a lower risk of lymph node metastasis among VIAC groups.

Endometrial Neoplasms↗

Detection of human papillomaviruses in cervical neoplasias using multiple sets of generic polymerase chain reaction primers.

OBJECTIVE: The aim of this study was to evaluate precisely the differences in the spectra of human papillomavirus (HPV) types detected by different generic primer pairs commonly used for detection of this extraordinarily heterogeneous virus. METHODS: Three sets of polymerase chain reaction (PCR) primers for the L1 open reading frame (ORF) and two sets for E6/E7 ORFs were used to detect HPVs in DNAs from 107 cervical tissues, including 77 cervical neoplasias. HPV types were determined by analysis of restriction fragment length polymorphisms (RFLPs) and nucleotide sequencing. RESULTS: A high overall detection rate of HPV in cervical neoplasias (76/77, 98.7%) was achieved by polymerase chain reaction (PCR) amplification with multiple sets of generic primers, while the detection rate for each individual primer pair varied from 48/77 (62%) to 70/77 (91%). Only in 34 of 77 cases (44%) were HPV DNAs positive for all sets of primer pairs. Further determination of HPV types by RFLPs and nucleotide sequencing showed inconsistencies between the PCR primer pairs used. CONCLUSION: Our study revealed that the HPV detection rate is critically affected by the choice of PCR primers, and that appropriate use of combinations of generic PCR primer sets followed by RFLP analyses is both necessary and sufficient for typing most HPVs in cervical lesions. More precise methods such as sequencing would be necessary in only a few cases.

Consensus Sequence↗

Magnetic resonance imaging in the evaluation of vaginal foreign bodies in a young girl.

A 7-year-old girl with foul-smelling, bloody vaginal discharge for more than 2 years was initially suspected of suffering from vaginal foreign bodies. Although plain radiography revealed no abnormal findings in the pelvis, magnetic resonance imaging (MRI) showed multiple low intensity objects and an intact vaginal wall. Four plastic toys were removed with forceps under general anesthesia. MRI is supposed to be the best technique for evaluating vaginal foreign bodies in young girls.

Child↗

Diagnostic accuracy of intraoperative imprint cytology in ovarian epithelial tumors.

OBJECTIVE: To evaluate imprint cytology (IC) as the intraoperative pathological consultations for ovarian epithelial tumors (OET). METHOD: We reviewed ICs obtained from 354 consecutive surgical specimens of OET. Cytological specimens were classified into five categories. Final pathological diagnoses were made according to the WHO classification. We performed logistic regression analysis, calculated the limits among benign, borderline, and malignant lesions, and analyzed the diagnostic accuracy. We also made receiver operating characteristic (ROC) curves regarding IC. RESULTS: The accuracies to differentiate benign and malignant lesions were 87.1 and 83.6%, respectively. In contrast, that of borderline lesions was 30.0%. The areas under ROC curves to diagnose benign, and malignant lesions were 0.888 (P<0.05) and 0.951 (P<0.05), respectively, that meant IC was significantly useful for diagnosis of malignancy. CONCLUSIONS: IC applied to OET was proved to be practically useful in establishing an intraoperative diagnosis by ROC curves.

Adult↗

Adjuvant hysterectomy in low-risk gestational trophoblastic disease.

OBJECTIVE: To evaluate the efficacy of adjuvant hysterectomy with chemotherapy for women with low-risk gestational trophoblastic disease. METHODS: One hundred fifteen consecutive Japanese women (16-52 years old) with low-risk gestational trophoblastic disease (46 with metastatic disease and 69 without) were treated initially with single-agent chemotherapy (etoposide in 85, methotrexate in 27, and actinomycin D in three) with or without adjuvant hysterectomy, and 97 patients (84.3%) achieved primary remission with those treatments. Eight women (9.4%) treated with etoposide required other regimens because of drug resistance or toxicities. The total dose of etoposide given to achieve primary remission was analyzed in 77 women who received etoposide alone or with adjuvant hysterectomy. RESULTS: In 34 women with metastatic disease, the mean (+/- standard deviation [SD]) total dose of etoposide was not significantly different with and without adjuvant hysterectomy (2857 +/- 842 mg versus 2815 +/- 815 mg; P =.957; Mann-Whitney U test). However, in 43 women without metastases, the total dose of etoposide was significantly less in those who had adjuvant hysterectomies than in those who did not (1750 +/- 635 mg versus 2545 +/- 938 mg; P <.05; Mann-Whitney U test). CONCLUSION: Adjuvant hysterectomy decreased the total dose of etoposide given to achieve primary remission in women with nonmetastatic, low-risk gestational trophoblastic disease. If the lesions of gestational trophoblastic disease are confined to the uterus and the woman has no desire to preserve fertility, she should be informed of adjuvant hysterectomy as a treatment option.

Adolescent↗

Detection of fetal HPCs in maternal circulation after delivery.

BACKGROUND: Circulation of mature fetal blood cells in the maternal blood for a certain postpartum period has been verified, but detailed study of the fetal HPCs has not been reported. The objective of this study was to evaluate the frequency and clearance of these cells in the peripheral blood of puerperal women. STUDY DESIGN AND METHODS: PBMNCs from 15 puerperal women who gave birth to male infants were cultured in semi-solid medium containing hematopoietic stimulating factors. Colonies formed in the medium were individually characterized, collected, and subjected to PCR amplification of the SRY gene on Y chromosome to confirm fetal origin. RESULTS: The mean numbers of fetal progenitor cell colonies isolated per mL of maternal blood were 1.63, 2.48, 0.56, 0.12, and 0 on the day of delivery, at 4 days, 1 month, 6 months, and 1 year after delivery, respectively. There was no difference in the ratio of fetal versus maternal colonies between erythroid and granulocyte/macrophage lineages. CONCLUSION: The present study demonstrated that a significant number of fetal HPCs circulate in the maternal blood for a duration of at least 6 months after delivery.

Delivery, Obstetric↗

Subsequent pregnancy outcome in patients with spontaneous resolution of HCG after evacuation of hydatidiform mole: comparison between complete and partial mole.

This study compared subsequent pregnancy outcome in patients with complete and partial hydatidiform moles. Among 1052 patients with molar pregnancy (complete mole, 801; partial mole, 251) monitored at Chiba University Hospital between 1981 and 1999, 891 patients (84.7%) had spontaneous resolution of human chorionic gonadotrophin (HCG) after mole evacuation, and 161 patients (15.3%) required chemotherapy. Of the 891 patients, 438 (49.2%) had 650 subsequent pregnancies. The pregnancy outcome was not significantly different in patients with complete and partial moles, and was comparable with that in the general Japanese population. The incidence of repeat molar pregnancy in patients with complete and partial mole (1.3 and 1.5% respectively) was 5-fold higher than that of the general population, while no increased risk of persistent gestational trophoblastic tumour (GTT) associated with later molar pregnancy was observed. During HCG follow-up, 10 patients (1.1%) developed secondary high-risk GTT between 14 and 54 months after mole evacuation. The incidence of high-risk GTT in patients with and without subsequent pregnancies was 0.46% (2/438) and 1.8% (8/453) respectively (P = 0.1243). In conclusion, patients with complete and partial mole can anticipate a normal future reproductive outcome, and pregnancies after experiencing hydatidiform mole may not affect the development of high-risk GTT.

Adolescent↗

Construction of the dual-functional RNA ligand against HCV NS3 protease and helicase.

Non-structural protein 3 (NS3) of hepatitis C virus (HCV) contains two distinct activities, protease and helicase which are essential for the HCV replication. In the previous study, we succeeded to obtain RNA aptamers, G9-I, G9-II and G9-III specific for the NS3 protease domain (delta NS3) by in vitro selection (1). As the result of mutational analysis in G9-I, we could obtain the minimum length of RNA structure, delta NEO-III maintaining the full inhibitional activity as shown in G9-I. Furthermore, we created a bi-functional novel RNA ligand, NEO-III-14U which was constructed by connecting delta NEO-III with (U)14 at the 3' terminal. NEO-III-14U was able to inhibit the unwinding of duplex DNA catalyzed by the Full-NS3 helicase activity as well as the protease activity in vitro. Consequently, we could obtain the dual-functional RNA ligand which could inhibit both NS3 protease and helicase activities essential for the HCV proliferation.

Base Sequence↗

[Studies of anti-cytomegalovirus IgG antibody positive rate and cytomegalovirus mononucleosis in adults].

We analyzed anti-Cytomegalovirus (CMV) IgG and IgM antibody (EIA) and anti-Epstein-Barr virus (EBV) viral capsid antigen (VCA) IgG and IgM antibody (FA) in adults during 1994-1999. We examined these IgM sero-positive patient's medical records, and diagnosed CMV mononucleosis and EBV mononucleosis. Anti-CMV antibody positive rates decreased from 87.6% in 1994 to 77.8% in 1999. Especially in twenties, anti-CMV antibody positive rates decreased from 65.2% in 1994 to 53.3% in 1999. On the other hand, anti-EBV VCA antibody positive rates were not changed (91-94%). Number of cases of CMV mononucleosis increased from 2 cases in 1994 to 16 cases in 1999, but EBV mononucleosis was not changed. These results suggested that increasing cases of CMV mononucleosis was influenced by decreasing anti-CMV antibody positive rate.

Adult↗

Increased and decreased expression of CD69 and CD23, respectively, in gravity-stressed lymphocytes.

BACKGROUND: Recent studies have shown that gravity-changing stress modulates expression levels of cell surface molecules on human lymphocytes. However, previous in vitro microgravity studies have been performed with lymphocytes treated with mitogenic agents. HYPOTHESIS: The aim of the study was to test if exposure of cells to gravity-changing stress alone alters the expression levels of cell surface molecules. Specifically, we examined whether the expression of activation markers is altered after exposure of lymphocytes to combinations of microgravity and hypergravity. METHODS: We used free-fall in parabolic flight for human subjects and a drop-shaft to expose peripheral blood mononuclear cells (PBMC) to gravity-changing stress. After such exposure, PBMC were isolated, and expression levels of CD69, CD23 and CD38 were estimated using three-color flow cytometry. RESULTS: Increased percentages of CD69-positive cells were observed with PBMC from 3 of 4 volunteers who undertook 10 parabolic flights. Exposure of blood to gravity-changing stress in the drop-shaft increased both ratios of CD69-positive cells and levels of CD69 expression on T and B cells. In contrast, the percentages of CD23-positive B cells was decreased. However, gravity-changing stress was not always followed by significant alteration in CD38 expression. CONCLUSIONS: Our findings suggest that CD69 and CD23 might be useful markers that are up- and down-regulated, respectively, after exposure of lymphocytes to gravity-changing stress.

ADP-ribosyl Cyclase↗

The RNA aptamer-binding site of hepatitis C virus NS3 protease.

Nonstructural protein 3 (NS3) of hepatitis C virus (HCV) is a trypsin-like protease and is essential for processing of viral polyprotein. Accordingly, it is a potential target for anti-HCV drugs. Recently we could isolate RNA aptamers (G9-I, II, and III) which bind and inhibit NS3 protease using in vitro selection strategy. In addition, G9-I aptamer showed noncompetitive inhibition. In order to elucidate the binding site of G9-I aptamer in NS3 protease domain (deltaNS3), we carried out alanine scanning mutagenesis at positive charged residues on the surface of deltaNS3. The result of binding analysis by surface plasmon resonance measurements and protease inhibition assay clarified that Arg161 as well as Arg130 of deltaNS3 are essential for interaction with G9-I aptamer. This region appears to be a potential targeting site for anti-HCV drugs.

Amino Acid Sequence↗

2',5'-oligoadenylate synthetase gene in chicken: gene structure, distribution of alleles and their expression.

We have cloned the gene for chicken 2',5'-oligoadenylate synthetase (ChOAS) by the method of polymerase chain reaction with use of ChOAS cDNA sequence. The ChOAS gene is composed of five introns and six exons containing all of the sequence of the ChOAS cDNA from the start to the stop codon. The first five exons of ChOAS gene which encode the OAS catalytic domain have a similar structure to HuOAS1 gene including the exon-intron boundaries. However, the length of introns of ChOAS gene is only 1/7 of those of HuOAS1 gene. The sixth exon of the ChOAS gene encodes the ubiquitin-like (UbL) domain of two consecutive sequence (UbL1 and UbL2) homologous to ubiquitin. ChOAS encoded in a single copy gene has at least two alleles, OAS(*)A and OAS(*)B. The differences between these two alleles are in the sixth exon of the gene; a 96-nucleotide sequence in the UbL1 portion of OAS(*)A is deleted from OAS(*)B. No OAS(*)B gene was detected in nine lines of chickens tested other than Leghorns. Almost the same levels of ChOAS-A and -B proteins induced physiologically in erythrocytes were detected in infant chickens (2-week-old), but in grown-up chickens (6-month-old) the level of erythrocyte OAS-B was markedly reduced in most of B/B chickens. Thus, the UbL domain of ChOAS is responsible for the maintenance of the OAS level in the tissue.

2',5'-Oligoadenylate Synthetase↗