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A Kikuchi

Publications and source records attributed to A Kikuchi.

At least 199 records · Page 11Linked to original sources
PubMed1997

Cell cycle-coupled relocation of types I and II topoisomerases and modulation of catalytic enzyme activities.

We visualized DNA topoisomerases in A431 cells and isolated chromosomes by isoenzyme-selective immunofluorescence microscopy. In interphase, topoisomerase I mainly had a homogeneous nuclear distribution. 10-15% of the cells exhibited granular patterns, 30% showed bright intranucleolar patches. Topoisomerase II isoenzymes showed spotted (alpha) or reticular (beta) nuclear patterns throughout interphase. In contrast to topoisomerase IIalpha, topoisomerase IIbeta was completely excluded from nucleoli. In mitosis, topoisomerase IIbeta diffused completely into the cytosol, whereas topoisomerases I and IIalpha remained chromosome bound. Chromosomal staining of topoisomerase I was homogeneous, whereas topoisomerase IIalpha accumulated in the long axes of the chromosome arms and in the centriols. Topoisomerase antigens were 2-3-fold higher in mitosis than in interphase, but specific activities of topoisomerase I and II were reduced 5- and 2.4-fold, respectively. These changes were associated with mitotic enzyme hyperphosphorylation. In interphase, topoisomerases could be completely linked to DNA by etoposide or camptothecin, whereas in mitosis, 50% of topoisomerase IIalpha escaped poisoning. Refractoriness to etoposide could be assigned to the salt-stable scaffold fraction of topoisomerase IIalpha, which increased from <2% in G1 phase to 48% in mitosis. Topoisomerases I and IIbeta remained completely extractable throughout the cell cycle. In summary, expression of topoisomerases increases towards mitosis, but specific activities decrease. Topoisomerase IIbeta is released from the heterochromatin, whereas topoisomerase I and IIalpha remain chromosome bound. Scaffold-associated topoisomerase IIalpha appears not to be involved in catalytic DNA turnover, though it may play a role in the replicational cycle of centriols, where it accumulates during M phase.

Antibody Specificity↗
PubMed1997

Synergistic activation of c-fos promoter activity by Raf and Ral GDP dissociation stimulator.

Ral, a member of small GTP-binding protein (G protein) superfamily, has been suggested to act downstream of Ras, since Ral GDP dissociation stimulator (RalGDS) has been found to be an effector protein of Ras. In this study, we examined the effects of RalGDS and Ral on gene expression using c-fos promoter linked to the luciferase reporter gene (c-fos-luciferase). RalGDS interacted with RasG12V/E37G (in which Gly-12 and Glu-37 were changed to Val and Gly, respectively) which failed to bind to Raf in COS cells. RafCAAX is an active Raf kinase targeted to the plasma membranes by virtue of the addition of a C-terminal localization signal from K-Ras. Transfection of either RalGDS or RafCAAX into NIH3T3 cells slightly stimulated c-fos-luciferase expression and cotransfection of both proteins greatly enhanced the expression. RalGDS and an activated Rac (RacG12V) did not act synergistically to stimulate c-fos-luciferase expression. Transfection of an activated Ral (RalG23V) stimulated c-fos-luciferase expression. Furthermore, cotransfection of RalG23V and an activated Ras (RasG12V) enhanced RasG12V-dependent c-fos-luciferase expression. However, RalG23V did not synergize with RafCAAX, RacG12V or RalGDS to stimulate the expression. These results show that RalGDS and Ral regulate c-fos promoter activity and suggest that RalGDS may activate c-fos promoter synergistically with the signal from Raf by transmitting the signal to a target other than Ral.

3T3 Cells↗
PubMed1997

Anti-HTLV-1 antibody positive cutaneous T-cell lymphoma.

BACKGROUND: Adult T-cell leukemia/lymphoma (ATLL) is a neoplasm of the mature helper T-lymphocyte. Human T-lymphotropic virus type 1 (HTLV-1) has been shown to be the cause of this neoplasm. Recently, however, the HTLV-1 genome has been found in some patients with cutaneous T-cell lymphoma (CTCL), which suggests a causal relation of HTLV-1 to CTCL. Thus, the relation between the HTLV-1 genome and CTCL, as well as the difference between ATLL and CTCL, have come into question. METHODS: The authors examined two patients with CTCL whose serum anti-HTLV-1 antibodies were constantly positive. The Southern blot technique, inverse polymerase chain reaction (IPCR), and polymerase chain reaction (PCR) with four sets of primers for gag, pol, env, and pX regions of HTLV-1 were used to clarify the distinctions between ATLL and CTCL. RESULTS: Clinically, one patient presented with multiple subcutaneous nodules with involvements of the internal organ, and the other patient was typical for mycosis fungoides. No integration of HTLV-1 DNA was detected by IPCR or the Southern blot technique in either patient. PCRs with the four sets of primers were all found to be positive for HTLV-1 except one. CONCLUSIONS: The authors conclude that ATLL should be differentiated from CTCL in view of the responsibility of HTLV-1 for promoting or maintaining CTCL.

Antigens, CD↗
PubMed1997

Intrauterine sonography for preoperative assessment of cervical invasion in endometrial carcinoma.

Cervical involvement is one of the major prognostic factors in carcinoma of the endometrium confined to the uterus. The purpose of this study was to determine whether intrauterine ultrasound with a high-frequency miniature probe can depict the degree of cervical involvement of the disease. Thirty-two women with endometrial carcinoma underwent preoperative transvaginal and intrauterine sonography. By both scans, the degree of cervical involvement was prospectively evaluated. Sonograms were compared with the findings from histologic examination. Intrauterine sonography was completed in 30 of the 32 patients. In these 30 patients, the degree of cervical involvement (none, endocervical gland, or cervical stroma) based on transvaginal scan was correct in 23 cases (77%), and that based on intrauterine scan was correct in 26 cases (87%). Three tumors with endocervical glandular involvement were correctly diagnosed by intrauterine sonography, whereas they were incorrectly diagnosed by transvaginal scan. The specificity and positive predictive value of intrauterine sonography for the assessment of the presence of cervical stromal invasion are 100% (26/26 and 3/3, respectively). Although this study is preliminary, our experience with intrauterine sonography shows that it has potential for assessing cervical stromal invasion in endometrial carcinoma.

Aged↗
PubMed1997

Analysis of peptides and proteins by temperature-responsive chromatographic system using N-isopropylacrylamide polymer-modified columns.

A new method of HPLC using packing materials modified with a temperature responsive polymer, poly(N-isopropylacrylamide) (PIPAAm), was developed. Homogeneous PIPAAm polymer and its copolymer with butyl methacrylate (BMA) were synthesized and grafted to aminopropyl silica by activated ester-amine coupling and they were used as packing materials. The surface properties and functions of the stationary phases are controlled by external temperature. Isocratic elution by aqueous mobile phase alone is the basis for separation of peptides and protein. The separation of the mixture of three peptides, insulin chain A and B and beta-endorphin fragment 1-27 was achieved by changing the column temperature with 0.9% NaCl aqueous solution as the sole eluent. Retention of peptides and proteins was controlled both by column temperature and by NaCl concentration in the aqueous mobile phases in this chromatographic system.

Acrylamides↗
PubMed1997

The distribution and expression of the two isoforms of DNA topoisomerase II in normal and neoplastic human tissues.

In mammalian cells, there are two isoforms of DNA topoisomerase II, designated alpha (170-kDa form) and beta (180-kDa form). Previous studies using cell lines have shown that the topoisomerase IIalpha and beta isoforms are differentially regulated during the cell cycle and in response to changes in growth state. Moreover, both isoforms can act as targets for a range of anti-tumour drugs. Here, we have analysed the normal tissue distribution in humans of topoisomerase IIalpha and beta using isoform-specific antibodies. In addition, we have studied expression of these isoforms in 69 primary tumour biopsies, representative either of tumours that are responsive to topoisomerase II-targeting drugs (breast, lung, lymphoma and seminoma) or of those that show de novo drug resistance (colon). Topoisomerase IIalpha was expressed exclusively in the proliferating compartments of all normal tissues, and was detectable in both the cell nucleus and cytoplasm. In biologically aggressive or rapidly proliferating tumours (e.g. high-grade lymphomas and seminomas), there was a high level of topoisomerase IIalpha, although expression was still detectable in colon tumours, indicating that expression of this isoform is not sufficient to explain the intrinsic drug resistance of colon tumours. Topoisomerase IIbeta was expressed ubiquitously in vivo and was localized in both the nucleoli and the nucleoplasm. This isoform was present in quiescent cell populations, but was expressed at a generally higher level in all tumours and proliferating cells than in normal quiescent tissues. We conclude that topoisomerase IIalpha is a strict proliferation marker in normal and neoplastic cells in vivo, but that topoisomerase IIbeta has a much more general cell and tissue distribution than has topoisomerase IIalpha. The apparent up-regulation of topoisomerase IIbeta in neoplastic cells has implications for the response of patients to anti-tumour therapies that include topoisomerase II-targeting drugs.

Antigens, Neoplasm↗
PubMed1997

Successful thoracoamniotic shunting using a double-flower catheter in a case of fetal cystic adenomatoid malformation associated with hydrops and polyhydramnios.

We describe a case of congenital cystic adenomatoid malformation treated by thoracoamniotic shunting using a double-flower catheter. An ultrasound examination at 25 weeks' gestation revealed a cystic mass within the fetal thoracic cavity, hydrops and polyhydramnios. Thoracoamniotic shunting under ultrasound guidance using a double-flower catheter was performed at 27 weeks. The procedure not only decompressed the lung cyst but also improved the secondary physiological changes, i.e. mediastinal shift, hydrops and polyhydramnios. A 2438-g male neonate was delivered at 37 weeks with no respiratory problems and resection of the right lower pulmonary lobe was successfully performed 24 h after birth.

Adult↗
PubMed1997

Direct intratumoral gene transfer of the herpes simplex virus thymidine kinase gene with DNA-liposome complexes: growth inhibition of tumors and lack of localization in normal tissues.

To constitute the site-specific expression of the herpes simplex virus thymidine-kinase (HSV-TK) gene in tumor cells, we have assessed the promoter function of the simian virus 40 (SV40) promoter and the 5'flanking region of c-erbB-2 gene using a luciferase-expressing reporter plasmid. After the transfection of the luciferase plasmid directed by the promoter region of c-erbB-2 gene, a large amount of luciferase activity was observed in c-erbB-2-expressing cells (Colo201, MCF-7, and HEC1-A), while none was detected in cells with no expression of c-erbB-2 protein (HRA and KF cells). On the other hand, a high level of luciferase activity was detected in all tumor cell lines tested, when the transfection was performed with SV40 promoter. The repeated transfection of the liposome-conjugated HSV-TK gene regulated by the SV40 promoter or by the promoter region of c-erbB-2 gene with cultivation in 100 micrograms/ml of aciclovir for 5 days in vitro resulted in growth inhibition for all four cell lines examined or for only c-erbB-2-expressing cells in the presence of SV40 promoter or c-erbB-2 promoter, respectively. Finally, direct injection of the DNA-liposome complex into established tumors in the presence of 50 mg/kg of aciclovir led to significant tumor volume reduction in all three tumors tested when SV40 promoter was employed. However, this anti-tumor effect was noted only in c-erbB-2-positive cells (Colo201 cells) upon intratumoral injection of HSV-TK gene regulated by c-erbB-2 promoter. In the case of intratumoral gene transfer, foreign DNA was detected in only one of seven mice by polymerase chain reaction (PCR) analysis performed 7 days following injection. When PCR analysis was carried out at 14 or 21 days following injection, no DNA signal was found at all. However, DNA was detected in several normal tissues at all three times tested in the case of intravenous injection. No abnormalities were seen in histologic examinations of normal tissues or in serum biochemical parameters following DNA liposome delivery. These results suggest that the direct gene transfer of HSV-TK gene regulated by tumor-specific transcriptional units may be one of the most clinically promising of the selective genetic strategies against cancer.

Acyclovir↗
PubMed1997

The loss of outer capsid protein P2 results in nontransmissibility by the insect vector of rice dwarf phytoreovirus.

A transmission-defective (TD) isolate of rice dwarf phytoreovirus lacked the ability to infect cells when derived from the virus-free insect vector Nephotettix cincticeps. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified virus showed that among six structural proteins, the P2 outer capsid protein (encoded by genome segment S2) was absent from the TD isolate, whereas all six proteins were present in the transmission-competent (TC) isolate. P2 was not detected on immunoblots of rice plants infected with the TD isolate. Genome segment S2 and its transcript were detected in both TD and TC isolates. Sequence analysis of the S2 segment of the TD isolate revealed the presence of a termination codon due to a point mutation in the open reading frame, which might explain the absence of P2 in the TD isolate. These results demonstrate that the P2 protein is one of the factors essential for infection by the virus of vector cells and, thus, influences transmissibility by vector insects.

Amino Acid Sequence↗
PubMed1997

Skin infiltration in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a type of acute leukemia showing unique clinical, morphological and cytogenetic features. A skin infiltration by APL cells is an extremely rare occasion, but there have been several case reports of leukemia cutis in APL, in which all-trans retinoic acid (ATRA) may have induced the skin infiltration. However, no immunohistochemical analyses of the APL cells in the skin have been done to date. A 30-year-old woman with APL developed multiple reddish purple nodules on the extremities in her second complete remission. Histological findings revealed a dense infiltration of medium to large atypical cells, which were positive for myeloperoxidase, throughout the dermis. Despite the conventional chemotherapy and ATRA therapy she died from disseminated intravascular coagulation during her third relapse. Leukemic cells in the peripheral blood before the treatment with ATRA revealed CD3-/CD4-/CD5-/CD7-/CD8-/CD10-/CD13++/CD14-/CD19 -/ CD20-/CD33++/CD38++/CD41-/Ia-, but they expressed CD3-/CD4-/CD5-/CD7++/ CD8-/CD10-/CD13++/CD14-/CD19-/CD20-/CD33++ /CD38++/CD41+/Ia+ after the treatment. We suggest that the alternation of the surface molecules on the tumor cells is closely associated with the skin infiltration of APL cells.

ADP-ribosyl Cyclase↗
PubMed1997

Effect of phenylboronic acid groups in copolymers on endothelial cell differentiation into capillary structures.

Copolymers (IABb) composed of N-isopropylacrylamide (I), N-(3-dimethylaminopropyl)-acrylamide (A), 3-acrylamidophenylboronic acid (B), and a hydrophobic comonomer, n-butyl methacrylate (b), were synthesized as cell culture substrata since we previously learned that bovine aortic endothelial cells (BAECs) cultured on the phenylboronic acid-containing copolymer (IAB) differentiated into capillary structures after 26 days culture. The synthesized IABb copo ymers contained higher boron and amine moieties than the IAB copolymer. The results of the dynamic contact angle measurement revealed that IABb copolymer-coated surfaces showed a relatively hydrophobic nature, changing to hydrophilic in response to the aqueous environment. BAECs cultured on the copolymer substrata developed into capillary networks after 7 days. This is probably due to the enrichment of boron and amine segments in the vicinity of the hydrophilic copolymer surface, enhancing more pronounced interaction of boronates with cell membrane glycocalyx. The introduction of n-butyl methacrylate into the polymers might enhance the diffusion of the hydrophobic segments to the bulk polymers and the concentration of relatively hydrophilic segments at the outermost polymer surfaces by contact with water. A copolymer (IAP) without boronic acid groups was also prepared using N-phenylacrylamide (P) as a comonomer instead of 3-acrylamidophenylboronic acid in the IAB copolymer to investigate the effect of boronic acid moieties on the capillary formation of the cultured cells. Although the endothelial cells seeded on the copolymer without boronic acid groups adhered during the early culture period, these cells showed neither proliferation nor differentiation and detached from the surface after 13 days. These results strongly support the opinion that the phenylboronic acid groups in the copolymers are responsible for the specific induction of tissue formation of BAECs through the interaction with glycoconjugates on the cell membranes.

Acrylamides↗
PubMed1997

Aggressive B-cell lymphoma induced by Epstein-Barr virus infection in erythrodermic cutaneous T-cell lymphoma.

The coexistence of two cutaneous non-Hodgkin's lymphomas of different lineage is rare. We report a patient with an indolent erythrodermic cutaneous T-cell lymphoma followed by an aggressive B-cell lymphoma. To our best knowledge, this is the first report describing Epstein-Barr virus-associated B-cell lymphoma in a patient with cutaneous T-cell lymphoma. We suggest that the long-standing cutaneous T-cell lymphoma, as well as the long-term chemotherapy, suppressed host immunity and caused reactivation of latent Epstein-Barr virus.

Female↗
PubMed1997

Immunohistochemical study of Ki-67 and DNA topoisomerase II in human endometrium.

Topoisomerase II (topo II) separates the chromosomes at the end of mitosis, and its expression is limited mostly to the S-to-G2/M phases of the normal cell cycle. We examined the expression of topo II immunohistochemically in 56 specimens of the human endometrium that were retrieved from surgical pathology files. Specimens included proliferative phase mucosa (n = 7), secretory phase mucosa (n = 5), nonatypical adenomatous hyperplasia (n = 7), atypical adenomatous hyperplasia (n = 7) and endometrioid adenocarcinoma (n = 30). We calculated the labeling index (LI) for topo II and correlated the findings with the LI for Ki-67. A significant positive correlation was obtained between the Ki-67 and topo II LIs in all of the specimens examined. The levels of the topo II and Ki-67 LIs in secretory phase endometrium were each significantly lower than in the other cases examined. The levels of the topo II and Ki-67 LIs in adenocarcinoma were significantly higher than those in proliferative phase endometrium and nonatypical hyperplasia. There were no significant differences between atypical hyperplasia and adenocarcinoma in the Ki-67 and topo II LIs. The level of the topo II LI in atypical hyperplasia was significantly higher than that in nonatypical hyperplasia, whereas the Ki-67 LI did not differ between atypical and nonatypical hyperplasia. The levels of the Ki-67 LI were significantly higher than those of the topo II LI in proliferative phase endometrium and in nonatypical hyperplasia, but no significant differences were observed between the LIs in atypical hyperplasia and adenocarcinoma. Topo II immunostaining can identify proliferative cells in routinely processed surgical pathology specimens of human endometrium. The relative overexpression of topo II as compared with Ki-67 in adenocarcinoma suggests a dysregulation or qualitative alteration in topo II associated with malignancy, as reported in other tissues. Such over-expression in atypical hyperplasia might reflect the possible premalignant nature of this type of endometrial hyperplasia.

Antigens, Neoplasm↗
PubMed1997

Apoptotic and proliferating cells in cutaneous lymphoproliferative diseases.

BACKGROUND: The cell production vs the cell loss rate in one of the most important parameters in evaluating growth and biological behavior of neoplasms. Individual cell disintegration in tissues, apoptosis, is a constant finding in various tumors and has been shown, by using several techniques, as a recognizable cell death that is different from necrosis. DESIGN: We studied the apoptosis-proliferation ratio in various lymphoproliferative disorders in the skin, including mycosis fungoides (MF), cutaneous T-cell lymphoma showing solid tumor mass (CTCL), B-cell lymphoma of the skin (BCL), lymphomatoid papulosis (LyP), and cutaneous pseudolymphoma by using terminal deoxyuridine triphosphate (dUTP)-biotin nick end labeling (TUNEL), a newly developed method to detect internucleosomal breaks characteristic of apoptotic cells. SETTING: University referral center. PATIENTS: Fifty patients with cutaneous lymphoproliferative diseases. MAIN OUTCOME MEASURES: Proliferation indexes and apoptosis index calculated by using immunohistochemical techniques. RESULTS: The proliferation indexes in pseudolymphoma, which were calculated by using immunohistochemical analyses with anti-proliferating cell nuclear antigen and anti-MIB-1 monoclonal antibodies, were significantly lower than the indexes of MF, CTCL, BCL, and LyP, whereas, the apoptosis index in Lyp was significantly higher than in any other lymphoproliferative diseases studied. The apoptosis-proliferation ratio in the tumor stage of MF, CTCL, and BCL was almost constant, but the ratios in LyP and the plaque stage of MF were significantly higher than in the other diseases studied. CONCLUSIONS: The clinical behavior of each lymphoproliferative disease in the skin seemed to be reflected in the apoptosis and proliferation indexes. We conclude that these indexes may become useful factors in the determination of the diagnosis and the prognosis for patients with lymphoproliferative diseases.

Antigens, Nuclear↗
PubMed1997

[A juvenile case of Lambert-Eaton myasthenic syndrome with severe emaciation].

Most of the patients with Lambert-Eaton myasthenic syndrome (LEMS) are over 40 years of age at onset and have a malignant neoplasm, especially pulmonary small cell carcinoma. Juvenile cases of LEMS are rare and have not been reported in Japan. We report a 21-year-old women whose onset of LEMS was at 17 years of age. In the early stage of the disease, she had limb muscle weakness and was diagnosed has having seronegative myasthenia gravis (MG) based on decrementing response in low frequency repetitive nerve stimulation, positive edrophonium test, and negative serum anti-acetylcholin receptor antibodies. Serum anti-voltage-dependent-calcium-channel (VGCC) antibody was negative with an available assay system. She was thymectomized and received anti-cholinesterases, corticosteroids, and cyclophosphamide, but their therapeutic effects were not evident. Two years later, she was confined to bed due to sever emaciation (Her body weight reduced from 47 Kg to 27 Kg.), bulbar palsy, and limb muscle weakness. She needed respiratory support and tube feeding. Type II fiber atrophy, which is non-specific, but is a common finding in LEMS, was seen in the biopsied muscle of the patient. On the other hand, postsynaptic folds and clefts of all seven motor end-plates in the specimen were normal, which is against the diagnosis of MG. Recently, she was found to have anti-VGCC antibody with an improved assay system. Despite vigorous examination, no malignancy or other autoimmune disorders have been found. 3,4-Diaminopyridine was effective to improve limb muscle powers, but she is still bedridden.

Adult↗