Biomedical subjects

T Fujino

Publications and source records attributed to T Fujino.

At least 127 records · Page 7Linked to original sources

PubMed1998

Distribution pattern and risk factors of pelvic and para-aortic lymph node metastasis in epithelial ovarian carcinoma.

The distribution of lymph node metastasis and the clinicopathologic risk factors for nodal involvement in ovarian carcinoma need to be clarified based on systematic lymph node dissection. We studied 115 patients with ovarian carcinoma who underwent systematic pelvic and para-aortic lymph node dissection between 1987 and 1997. The incidence and distribution of lymph node metastasis are described and the clinico-pathologic risk factors for nodal involvement are investigated. Based on the occurrence of lymph node metastasis in the early stages, the incidence of solitary node involvement and the distribution of lymph node metastasis, we conclude that the primary site of nodal involvement in ovarian carcinoma is the para-aortic node (PAN), especially PAN superior to the inferior mesenteric artery (IMA). By univariate analysis, clinical stage, histologic type (mucinous vs. others), grade, multiple peritoneal metastases, peritoneal cytology, volume of ascites and serum CA125 level were correlated with overall incidence of lymph node metastasis. By performing a multivariate analysis with the clinical stage excluded, it was revealed that grade and peritoneal cytology were independent factors for PAN metastasis (p < 0.0025 and < 0.001, respectively) and that multiple peritoneal metastases and PAN metastasis were significant predictors of pelvic node metastasis (p < 0.01 and < 0.005, respectively). In conclusion, the PANs superior and inferior to IMA should be explored in staging of ovarian carcinoma that appears to be confined to the ovaries. To determine accurately the extent of disease, both the para-aortic and pelvic areas may need to be sampled or dissected in the case of ovarian carcinoma involving the peritoneal surfaces.

Adenocarcinoma, Clear Cell↗

PubMed1998

Carboxyl-terminal 15-amino acid sequence of NFATx1 is possibly created by tissue-specific splicing and is essential for transactivation activity in T cells.

NFAT regulates transcription of a number of cytokine and other immunoregulatory genes. We have isolated NFATx, which is one of four members of the NFAT family of transcription factors and is preferentially expressed in the thymus and peripheral blood leukocytes, and an isoform of NFATx, NFATx1. Here we provide evidence showing that 15 amino acids in the carboxyl-terminal end of NFATx1 are required for its maximum transactivation activity in Jurkat T cells. A fusion between these 15 amino acids and the GAL4 DNA binding domain was capable of transactivating reporters driven by the GAL4 DNA binding site. Interestingly, this 15-amino acid transactivation sequence is well conserved in NFAT family proteins, although the sequences contiguous to the carboxyl-terminal regions of the NFAT family are much less conserved. We also report three additional isoforms of NFATx, designated NFATx2, NFATx3, and NFATx4. This transactivation sequence is altered by tissue-specific alternative splicing in newly isolated NFATx isoforms, resulting in lower transactivation activity in Jurkat T cells. NFATx1 is expressed predominantly in the thymus and peripheral blood leukocyte, while the skeletal muscle expressed primarily NFATx2. In Jurkat cells, transcription from the NFAT site of the IL-2 promoter is activated strongly by NFATx1 but only weakly by NFATx2. These data demonstrate that the 15-amino acid sequence of NFATx1 is a major transactivation sequence required for induction of genes by NFATx1 in T cells and possibly regulates NFAT activity through tissue-specific alternative splicing.

Alternative Splicing↗

PubMed1998

Characterization of membrane-bound serine protease related to degradation of oxidatively damaged erythrocyte membrane proteins.

It has been shown that erythrocyte membrane proteins become susceptible to degradation by membrane-bound serine protease activity after oxidative modification of the membranes (M. Beppu, M. Inoue, T. Ishikawa, K. Kikugawa, Biochim. Biophys. Acta 1196 (1994) 81-87). The aim of the present study was to clarify the presence of the serine protease in oxidized erythrocyte membranes and to characterize the selectivity of the enzyme to oxidized proteins. Human erythrocytes were oxidized in vitro with xanthine/xanthine oxidase/Fe(III) and oxidized membranes isolated. Proteolytic activity of the membranes toward spectrin obtained from oxidized membranes and bovine serum albumin oxidized with H2O2/horseradish peroxidase was increased by membrane oxidation, and the degradability of the substrates was increased by substrate oxidation. The proteolytic activity was inhibited by the serine protease inhibitor diisopropyl fluorophosphate (DFP). The 72 kDa and 80 kDa proteins in the membranes were labeled by [3H]DFP when detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions and subsequent fluorography. The 72 kDa protein was found to be a serine enzyme, acetylcholine esterase. The 80 kDa protein appeared to be responsible for the degradation of oxidatively damaged proteins. The 80 kDa protein was loosely bound to membranes and readily solubilized into a 0.1% NP-40 detergent solution. The presence of the same 80 kDa protease in intact erythrocyte cytosol was suggested. The increased serine protease activity in oxidized membranes can result from the increased adherence of the cytosolic 80 kDa serine protease to the membranes due to oxidation.

Animals↗

PubMed1998

Bcl-2 expression and prognosis of patients with endometrial carcinoma.

Bcl-2 protein inhibits apoptosis, reduces the requirement for growth factors, and thereby extends the survival of cells. Recent findings of Bcl-2 in several solid tumors suggest that it might contribute to the genesis of some types of cancer. Over-expression of Bcl-2 might play a role in carcinogenesis and malignant progression of endometrial carcinoma. The aims of this study were to determine Bcl-2 expression in endometrial carcinoma in relation to other histopathologic prognostic factors, and to test its prognostic significance in patients with endometrial carcinoma. A total of 61 endometrioid-type endometrial carcinomas were immunohistochemically investigated for Bcl-2 expression on cryostat sections. Bcl-2 localization was observed in cytoplasm in 18 tumors, in nucleus in 27 tumors, or in both in 5 tumors. In 11 tumors, Bcl-2 was observed neither in cytoplasm nor in nucleus. There was not a statistically significant relationship between grade of tumor and Bcl-2 expression. Cytoplasmic Bcl-2 became less frequently expressed as the tumor invaded the myometrium deeper (p < 0.025). Retroperitoneal lymph-node dissection was performed in 57 patients. Multiple-regression analysis showed that lymph-vascular space invasion and nuclear expression of Bcl-2 were correlated to pelvic lymph-node metastasis (p < 0.0001 and < 0.05 respectively). Univariate Cox regression analysis revealed that nuclear Bcl-2 expression was associated with shorter survival (p < 0.05) than that of patients with cytoplasmic Bcl-2 expression. Pelvic node metastasis was a significant prognostic factor for patients who underwent systematic retroperitoneal lymph-node dissection. Cox multivariate-regression analysis revealed that pelvic node metastasis and cervical invasion were the most important prognostic factors in this series of patients. When the analysis was made after exclusion of pelvic node metastasis, histologic grade (hazard ratio = 2.4), cervical invasion (hazard ratio = 3.7) and nuclear Bcl-2 expression (hazard ratio = 11.5) were shown to be significant predictors of survival of the patients. These results indicate that aberrant Bcl-2 expression might be involved in malignant progression of endometrioid-type endometrial carcinoma. Site of Bcl-2 localization may be an important predictor of prognosis for patients with endometrioid-type endometrial carcinoma.

Adult↗

PubMed1998

Escherichia coli cytidine deaminase provides a molecular model for ApoB RNA editing and a mechanism for RNA substrate recognition.

ApoB RNA-editing enzyme (APOBEC-1) is a cytidine deaminase. Molecular modeling and mutagenesis show that APOBEC-1 is related in quaternary and tertiary structure to Escherichia coli cytidine deaminase (ECCDA). Both enzymes form a homodimer with composite active sites constructed with contributions from each monomer. Significant gaps are present in the APOBEC-1 sequence, compared to ECCDA. The combined mass of the gaps (10 kDa) matches that for the minimal RNA substrate. Their location in ECCDA suggests how APOBEC-1 can be reshaped to accommodate an RNA substrate. In this model, the asymmetrical binding to one active site of a downstream U (equivalent to the deamination product) helps target the other active site for deamination of the upstream C substrate.

APOBEC-1 Deaminase↗

PubMed1998

Human apolipoprotein B RNA editing deaminase gene (APOBEC1).

Genomic clones encoding the human APOBEC1 gene and its 5' flanking region have been isolated and characterized. The human gene contains five coding exons. The introns dividing these exons correspond exactly to those found in the mouse gene. The translation initiation site, ATG, is located in exon 2 at the same site as in the mouse. The 5' flanking sequence contains two Alu repeats of the Sq family. Primer extension analysis demonstrated the presence of two major transcription initiation sites. The first transcription initiation site delineates the beginning of a noncoding first exon and resides downstream of the first Alu sequence. The second transcription initiation site is within the second Alu repeat. This Alu repeat resides within the first intron, which is spliced out of the transcript from the first start site. Neither transcription initiation site has a TATA or CCAT box. Comparison with the mouse gene suggests that the Alu sequence insertion split the intestinal promoter and that subsequently the down-stream Alu sequence took on a promoter function. No evidence was found for a far upstream non-tissue-specific promoter similar to that demonstrated in the mouse gene. Rather, consideration of results from the marsupial APOBEC-1 gene suggests that this upstream mouse promoter may have had a later evolutionary origin.

APOBEC-1 Deaminase↗

PubMed1998

Prenatal identification of mos 45,X/46,X,+mar in a normal male baby by cytogenetic and molecular analysis.

We report a case of mos 45,X/46,X,+mar, diagnosed prenatally by amniocentesis, whose physical examination, including external and internal organs, along with serum testosterone values were normal five years after delivery. The mosaic karyotype was seen in 146 of 240 cells examined (amniotic fluid cells, 110/65; placental chorionic villi: 5/4; cord blood, 21/81; cultured skin fibroblasts, 10/90) from 386 metaphases, and the marker chromosome appeared as a small non-fluorescent acrocentric chromosome. All autosomes appeared normal, and no normal Y chromosome could be demonstrated. Analysis of 26 Y-chromosome loci by molecular techniques such as PCR, Southern analysis using multiple Y-specific DNA probes, and Hae III restriction endonuclease assessment of male-specific repeated DNA in the heterochromatic region of the Y chromosome, and fluorescence in situ hybridization (FISH), revealed the marker was derived from a Y chromosome including p terminal to q11.23, and paracentric inversion in the remaining Y long arm. The formation of testes can be considered as existence of SRY (sex-determining region of Y) as a testis-determining factor. The present report illustrates the importance of FISH and molecular techniques as a complement to cytogenetic methods for accurate identification and characterization of chromosome rearrangements in prenatal diagnosis.

Adult↗

PubMed1998

The immunosuppressive compound FK506 does not affect expulsion of Echinostoma trivolvis in C3H mice.

C3H/HeN mice were infected with Echinostoma trivolvis metacercariae on day 0, given intramuscular injections of the immunosuppressive agent FK506 daily for 5 or 7 days, and necropsied on days 5, 8, 12, 15, 20, and 30 postinfection (p.i.). Control mice were infected with the echinostomes but were not treated with FK506. A significant reduction in mastocytosis was seen from day 12 to day 15 p.i. in the treated group. No reduction was observed in numbers of goblet cells and eosinophils in the treated group. The number of white blood cells was lower in the treated mice than in the controls. No significant difference in the optical density values of immunoglobulins appeared in control versus treated mice. Treatment with FK506 did not delay worm expulsion markedly, probably because the drug did not suppress goblet-cell hyperplasia. Increased mucus production associated with goblet-cell hyperplasia is primarily involved in the expulsion of E. trivolvis in murine hosts.

Animals↗

PubMed1998

Retroviral gene transfer for the assignment of Fanconi anemia (FA) patients to a FA complementation group.

Fanconi anemia (FA) is an autosomal recessive disorder characterized by bone marrow failure, cancer susceptibility, and a variety of developmental defects. The disease is clinically heterogeneous; eight different complementation groups (FA A-H) and, thus, genetic loci have been discovered. Two genes, FAA and FAC, have been cloned. Disease-associated mutations have been detected and rapid mutation screening makes possible the assignment of patients without resorting to time-consuming cell fusion and complementation analysis. Amplification of specific cDNAs from RNA followed by direct or indirect sequence analysis is a standard method for mutation detection. During the course of such examinations of the FAC gene, we have noted that frequently only one of the expressed alleles is successfully amplified. This can lead to false assignment of patients to a complementation group. As we report here, such cases can be rapidly clarified by retroviral gene transfer and complementation analysis.

Cell Cycle↗

PubMed1998

Enhanced expression of heparin-binding EGF-like growth factor and its receptor in hypertrophied left ventricle of spontaneously hypertensive rats.

OBJECTIVES: Although heparin-binding epidermal growth factor-like growth factor (HB-EGF) is thought to produce hypertrophy in isolated cardiomyocytes via an autocrine mechanism, the pathophysiological role of HB-EGF, in myocardial hypertrophy in vivo, is not yet known. To investigate the involvement of HB-EGF in cardiac remodeling associated with hypertension in vivo, we assayed the expression of HB-EGF mRNA and protein in the left ventricle (LV) during the development of left ventricular hypertrophy in spontaneously hypertensive rats (SHR). METHODS: Prior to sacrifice and assay of HB-EGF and EGF-receptor (EGF-R) mRNA, morphologic and hemodynamic variables were measured in SHR and in age-matched Wistar Kyoto rats (WKY). At 5, 9 and 12 weeks of age, rats were killed, their hearts were removed, and the expression of HB-EGF and EGF-R mRNA and protein were measured. In addition, SHR and WKY were treated with enalapril, atenolol, or both for 4 weeks. RESULTS: In untreated SHR, double products (i.e. systolic blood pressure (sBP) multiplied by heart rate (HR), an index of mechanical load, peaked at 9 weeks. Expression of HB-EGF mRNA was also observed to peak in these animals at 9 weeks, while expression of EGF-R mRNA increased from 5 to 9 weeks, but remained constant thereafter. In untreated WKY, double products and EGF-R mRNA expression did not change over time, whereas the level of HB-EGF message increased gradually. Antibody to HB-EGF reacted primarily with myocyte membranes in SHR, whereas antibody to EGF-R reacted mainly with interstitial cells in these animals. The angiotensin-converting enzyme inhibitor, enalapril, markedly decreased sBP in SHR, whereas the beta 1-adrenoreceptor antagonist, atenolol, significantly decreased HR. While neither alone affected the expression of HB-EGF mRNA, their combination significantly reduced the expression of HB-EGF mRNA, as well as double products, in these rats, but had no effect on expression of EGF-R mRNA. CONCLUSIONS: The enhanced expression of HB-EGF mRNA and protein in LV of SHR suggest that this growth factor may play an important role during the early development of LV hypertrophy and cardiac fibrosis in SHR. The association between double products and HB-EGF expression suggest that the latter may be induced by increased mechanical load and may contribute, in turn, to cardiac remodeling.

Adrenergic beta-Antagonists↗

PubMed1998

The expulsion of Echinostoma trivolvis caused by goblet cell hyperplasia in severe combined immunodeficient (SCID) mice.

Mice with severe combined immunodeficiency (SCID), lacking functional T and B lymphocytes, were each infected with 40 Echinostoma trivolvis metacercarial cysts on day 0. The mice of the test group were given intramuscular injections of dexamethasone (DEX) daily for 2 weeks and necropsied on days 5, 8, 12, 15, 20 and 30 post-infection (p. i.). The control mice, not treated with DEX, were each infected with 40 echinostome cysts on day 0 and necropsied on the same days as the DEX-treated mice. In the control mice, worm rejection began about day 8 p. i. and the worms were completely rejected by day 15 p. i., corresponding to the peak in goblet cell hyperplasia, about day 12 p. i. In the DEX-treated mice, goblet cell hyperplasia was significantly suppressed and the worms were retained until day 15 p. i., and then rejected after the last treatment with DEX. The number of mucosal mast cells, that increased with worm infection and peaked about day 15 p. i., was apparently suppressed by treatment with DEX. The eosinophil number in the controls increased on day 15 p.i. approximately and then decreased. The eosinophil number in the DEX-treated mice increased as in the controls, but was significantly suppressed compared to that of the controls during the period of the experiment. Enzyme-linked immunosorbent assay (ELISA) showed no marked rise in titres of the sera IgM, IgA and IgG throughout the experiment in both groups. These results indicate that DEX-treatment delayed the rejection of E. trivolvis from the small intestine of SCID mice in association with the suppression of goblet cell hyperplasia. It is concluded that the host immune system is not involved in the rejection of E. trivolvis and the effector cells for worm rejection are goblet cells that markedly increase in numbers by infection with E. trivolvis.

Animals↗

PubMed1998

A novel acyl-CoA synthetase, ACS5, expressed in intestinal epithelial cells and proliferating preadipocytes.

We report here the identification, characterization, and expression of a novel rat acyl-CoA synthetase (ACS) designated as ACS5. ACS5 consists of 683 amino acids and is approximately 60% identical to the previously characterized ACS1 and ACS2. ACS5 was overproduced in Escherichia coli cells and then purified to near homogeneity. The purified enzyme utilized a wide range of saturated fatty acids similar to those utilized by ACS1 and ACS2, but differed in its preference for C16-C18 unsaturated fatty acids. Northern blot analysis revealed that ACS5 mRNA is present most abundantly in the small intestine, and to a much lesser extent in the lung, liver, adrenal gland, adipose tissue, and kidney. In situ hybridization of rat ileum revealed abundant accumulation of ACS5 transcripts in foveolar epithelial cells. The hepatic level of ACS5 mRNA was significantly increased by refeeding a fat-free high sucrose diet and reduced by fasting or refeeding a high cholesterol diet, whereas that in the small intestine was not significantly altered by various dietary conditions. In contrast to the absence of ACS1 mRNA in undifferentiated 3T3-L1 preadipocytes, ACS5 mRNA was present in proliferating 3T3-L1 preadipocytes and its level remained unaltered during differentiation, suggesting that ACS5 may provide the acyl-CoA utilized for the synthesis of cellular lipids in proliferating preadipocytes.

Adipocytes↗

PubMed1998

A novel low-density lipoprotein receptor-related protein with type II membrane protein-like structure is abundant in heart.

We report herein the identification of a novel member of the low-density lipoprotein receptor (LDLR) family termed LDLR-related protein 4 (LRP4). Murine LRP4 cDNA encodes a 1113-amino-acid type II membrane-like protein with eight ligand-binding repeats in two clusters. Southern blot analysis of genomic DNA from several different organisms suggests the presence of LRP4 homologues in chicken lacking the gene encoding apolipoprotein E, which is recognized by the ligand-binding repeats of LDLR. LRP4 transcripts were detected almost exclusively in heart in mouse and humans. Despite the presence of the ligand-binding repeats, COS cells transfected with LRP4 did not show surface-binding of beta-migrating very-low-density lipoprotein, suggesting that LRP4 plays a role in a pathway other than lipoprotein metabolism.

Amino Acid Sequence↗

PubMed1998

Elucidating the mechanism of cesium-induced sustained monomorphic ventricular tachycardia in rabbits.

The mechanisms of sustained ventricular tachycardia (VT) induced by large cumulative dose of cesium chloride (Cs) remains unclear. Seven anesthetized rabbits were intravenously injected with Cs (1 mmol/kg) 3 times at 20-min intervals. The surface ECG and monophasic action potential of the left ventricular endocardium were simultaneously recorded. In another 12 rabbits, transmembrane action potentials of right ventricular muscles were recorded with glass microelectrodes. In experiments in vivo, sustained monomorphic VT was induced after the third injection of Cs, whereas the early afterdepolarization (EAD)-related nonsustained polymorphic VT was induced after the second injection. Overdrive pacing during the sustained VT resulted in postdrive acceleration. The pacing and recovery cycle lengths showed an inverse relation. In experiments in vitro, preparations were superfused with Tyrode's solution containing 7.5 mM Cs. Cs initially induced EADs. Additional exposure to Cs depolarized the membrane potential, which consequently attained threshold, producing spontaneous activities. Further exposure resulted in an induction of sustained rhythms that were accelerated by overdrive pacing. Our results indicate that the sustained rhythms at low membrane potential induced by a long exposure to Cs in vitro may underlie an electrophysiologic mechanism for the sustained VT induced after large cumulative dose of Cs in vivo.

Action Potentials↗

PubMed1998

Accompanying arteries of the cutaneous veins and cutaneous nerves in the extremities: anatomical study and a concept of the venoadipofascial and/or neuroadipofascial pedicled fasciocutaneous flap.

The arterial anatomy of the accompanying arteries of the cutaneous veins and cutaneous nerves in the extremities was investigated in 10 fresh cadavers that had been injected with a lead oxide-gelatin mixture throughout the entire body. It is well known that cutaneous nerves have neurocutaneous perforators, but it was found that cutaneous veins also have their own accompanying arteries as well. The accompanying arteries of the cutaneous veins had branches not only to the vein wall, but also to the skin, i.e., venocutaneous perforators. Based on these findings, the concept of the adipofascial pedicled fasciocutaneous flap using the accompanying arteries of the cutaneous veins, cutaneous nerves, or both was proposed.

Adipose Tissue↗

PubMed1998

Association of mutations in the core promoter and precore region of hepatitis virus with fulminant and severe acute hepatitis in Japan.

It was recently reported that mutations in the precore and core promoter region of hepatitis B virus (HBV) are associated with fulminant hepatitis. The aim of this study was to investigate the association of mutations in the precore and core promoter region of HBV with fulminant and severe acute hepatitis. We studied Japanese patients with acute HBV infection, including seven patients with fulminant hepatitis, 12 with severe acute hepatitis and 41 with acute self-limited hepatitis. The presence of HBV mutants was examined by using a point mutation assay to detect a G to A transition at position 1896 in the precore region and an A to T transition at position 1762 and a G to A transition at position 1764 in the core promoter region. Significant differences in the proportion of mutations in the precore or core promoter region were present between patients with fulminant hepatitis and self-limited acute hepatitis (7/7 (100%) vs 4/41 (9.8%), P<0.01) and between severe acute hepatitis and self-limited acute hepatitis (6/12 (50.0%) vs 4/41 (9.8%), P<0.01). The frequency of mutation increased proportionately with the severity of disease in patients with acute HBV infection. Fulminant hepatitis B in Japan is closely associated with mutations in the core promoter and precore gene of HBV. Point mutation assays for HBV precore and core promoter analysis may be useful to predict the outcome of liver disease in patients with acute HBV infection.

Acute Disease↗

PubMed1998

Ultrashort-time FISH for identification of the sex of peripheral-blood lymphocytes and preimplantation embryos.

OBJECTIVE: The aim of this study was to shorten the time required for sex determination using peripheral-blood lymphocytes and blastomeres of human preimplantation embryos by fluorescence in situ hybridization (FISH). METHODS: Peripheral-blood lymphocytes from a male and a female, and 8 blastomeres from 2 preimplantation embryos were analyzed by FISH. The probes used were DYZI and DXZI. The hybridization time was shortened from overnight to 30 minutes or 5 minutes, and the accuracy of FISH was compared between 5-minute, 30-minute and overnight hybridization. RESULTS: The accuracy of the identification of the sex of lymphocytes by 5-minute hybridization FISH was more than 90%, and was the same as that achieved by 30-minute- and overnight hybridization FISH. In 5-minute hybridization FISH, the entire process was only 63 minutes. Of the 8 blastomeres, it was possible to identify the sex of 5 and was impossible to determine the sex of 1, with 2 being lost during the procedure. CONCLUSIONS: We have established on ultrashort-time FISH method for sex determination that takes only 63 minutes.

Blastocyst↗

PubMed1998

Radiofrequency catheter ablation of left ventricular outflow tract tachycardia: report of two cases.

Idiopathic ventricular tachycardia (VT) originating from the left ventricular outflow tract (LVOT) is rare. We report two patients whose QRS configuration during VT commonly showed an inferior axis and monophasic R waves in all the precordial leads. The mechanism of these VTs appeared to be triggered activity. From mapping and ablation, the origin of these VTs was determined to be in the most posterior LVOT, corresponding to the aortomitral continuity (left fibrous trigone).

Catheter Ablation↗