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T Fujiwara

Publications and source records attributed to T Fujiwara.

At least 361 records · Page 20Linked to original sources
PubMed1998

Isolation, mapping, and functional analysis of a novel human cDNA (BNIP3L) encoding a protein homologous to human NIP3.

We have isolated a novel cDNA that encodes a product showing significant sequence homology (56% identity) to human NIP3, a protein thought to interact with adenovirus E1B19kD and human BCL2 proteins. This cDNA contains an open reading frame of 657 nucleotides encoding a 219 amino acid polypeptide. The gene, designated BNIP3L, was expressed in all 16 normal human tissues examined; we mapped it to chromosome band 8p21 by fluorescence in situ hybridization. Introduction of the BNIP3L gene into six different cancer-cell lines caused significant growth suppression in each of them, while no such effect occurred when the antisense cDNA or the vector DNA was transfected, indicating that BNIP3L may function as a tumor suppressor.

Amino Acid Sequence↗
PubMed1998

Isolation and characterization of a novel human pancreas-specific gene, pancpin, that is down-regulated in pancreatic cancer cells.

By means of the differential display method, we isolated a novel human gene that is expressed specifically in pancreas. The cDNA, designated "pancpin," contained an open reading frame of 1,215 nucleotides encoding a 405 amino acid protein, showing a high degree of similarity to serine protease inhibitors belonging to the serpin superfamily. To investigate its possible role in pancreatic carcinogenesis, we looked for genetic alterations of this gene in pancreatic cancer cell lines and primary pancreatic cancer tissues. Expression of pancpin was barely detectable in any of the four pancreatic cancer cell lines examined, and very weak also in 10 of 13 pancreatic cancer tissues. A somatic missense mutation at codon 221 was found in two of 16 primary pancreatic cancers. These findings indicate that down-regulation of pancpin expression may play a significant role in development or progression of pancreatic cancer.

Amino Acid Sequence↗
PubMed1998

[Participation of apoptosis in renal amyloidosis].

Renal amyloidosis shows symptoms of renal dysfunction due to the deposition of amyloid protein in the kidney. Recently, it was reported that apoptosis plays an important role in the pathogenesis of type-2 diabetes mellitus and Alzheimer's disease of which amyloid deposition is seen in the tissue. We investigated whether or not apoptosis and related factors are observed in renal amyloidosis. In situ nick end labeling (TUNEL) was performed in seven autopsied renal tissues with primary and secondary amyloidosis and 10 autopsied renal tissues without renal disease as the control. The number of TUNEL-positive cells was significantly increased in both the glomeruli and tubulus of the kidney with amyloidosis than in the control. Electron microscopic analysis was performed on one biopsied renal tissue with amyloidosis and six biopsied renal tissues with minor abnormalities as the control. Typical apoptotic cells were observed only in the former. Bax product, an inducer of apoptosis, and Bcl-2 protein, an inhibitor of apoptosis, were examined immunohistochemically in the seven autopsied renal tissues with amyloidosis and 10 autopsied control tissues. Bax was overexpressed in the tubulus and glomeruli of subjects with renal amyloidosis, compared to the normal controls. However, Bcl-2 protein was not detected in the glomeruli in any of the subjects examined. These results indicate that apoptotic cells are increased in number in renal amyloidosis and Bax overexpression may play an important role in this increase.

Aged↗
PubMed1998

Lesion-to-background ratio in nonattenuation-corrected whole-body FDG PET images.

UNLABELLED: The purpose of this study was to compare the diagnostic efficacy of attenuation-corrected and nonattenuation-corrected whole-body 18F-fluorodeoxyglucose (FDG) PET images to determine an adequate method that can semiquantitatively evaluate nonattenuation-corrected images. METHODS: Whole-body PET studies were performed in 24 fasting patients with various tumors (lung cancers, n = 18; mediastinal tumors, n = 4; breast cancers, n = 2) 30-40 min after a bolus injection of 18F-FDG. Transmission scans followed emission data acquisition. Reconstructed attenuation-corrected and uncorrected images were displayed simultaneously and the relative FDG uptake in lesions and corresponding background areas was evaluated by the region of interest method. Both types of images were also compared with X-CT scans and conventional nuclear medicine scans for diagnostic efficacy. RESULTS: Attenuation-corrected and uncorrected images were found to be equally sensitive for detecting lesions. There was a strong linear correlation between lesion-to-background (L/B) ratios calculated on attenuation-corrected and uncorrected images (r = 0.98; p < 0.001). Significant differences in L/B ratios between attenuation-corrected and uncorrected images were present in only 6 of 55 lesions (11%). Standardized uptake ratios (SURs) in attenuation-uncorrected images did not correlate with SURs in attenuation-corrected images nor with L/B ratios in uncorrected images. CONCLUSION: The efficacy of attenuation-uncorrected FDG PET images in evaluating tumors is similar to that using attenuation-corrected images. Uncorrected images provide not only clinically useful but also quantitative information equivalent to that provided by attenuation-corrected images. However the L/B ratio is the only available index that can be used for quantification of uncorrected images.

Breast Neoplasms↗
PubMed1998

[Molecular surgery for human colorectal cancer with tumor suppressor p53 gene transfer].

Recent advances in molecular biology have demonstrated that multistep genetic alterations are involved in the carcinogenesis of human colorectal cancer and that alteration of the p53 gene by mutation, deletion, or rearrangement is a major factor in this process. Human gene therapy has become a reality with the development of effective techniques for delivering the gene to the target cells. The efficacy of gene therapy for various types of genetic disease now being evaluated in clinical trials. These findings led us to develop a novel gene therapeutic strategy for human colorectal cancer that could replace the abnormal p53 gene using a recombinant, replication-defective adenoviral vector (termed Adp53). Infection with Adp53 induced rapid apoptotic cell death in DLD-1 and LoVo human colorectal cancer cell lines differing in their p53 status. Treatment with cisplatin following infection with Adp53 significantly suppressed the growth of WiDr colorectal cancer cells compared to single treatments alone. Thus restoration of wild-type p53 function exhibited an antitumor effect by inducing apoptosis as well as by markedly enhancing the effect of common chemotherapeutic agents in human colorectal cancer cells. In addition, Adp53 infection was antiangiogenic in SW620 human colorectal cancer cells. The application of this technology to human cancer therapy is now in progress. The article reviews recent highlights in this rapidly evolving field.

Adenoviridae↗
PubMed1998

[Long-term follow-up of patients with small St. Jude aortic valve prostheses].

Thirty-five patients received small sized 19 or 21 mm valves (group I) and 53 patients received 23 or 25 mm valves (group II). At follow-up a significant reduction in the left ventricular mass was found for both patient groups (p < 0.0001). The patients in group I had higher peak pressure gradients than did those in group II. However, there was no significant difference between the two groups, or any significant correlation between peak pressure gradients and body surface area. Actuarial survival was 84.7% at 15 years for group I and 85.9% at 17 years for group II. Actuarial freedom from valve-related events was 91.4% at 15 years for group I and 82.7% at 17 years for group II. There was no significant difference in survival or valve-related event free curves between the two groups. After implantation of small SIM valves, significant left ventricular mass regression was obtained and the results were comparable to those for valves of other sizes. The long-term performance of aortic valve replacement with small valves was satisfactory as judged by improvement in the functional class of patients, survival statistics, the durability of the prosthesis, and valve related morbidity comparable to that of valves of other sizes.

Aged↗
PubMed1998

Human colon cancer cells express the functional Fas ligand.

Fas ligand (FasL) belongs to the TNF superfamily. It is induced in activated lymphocytes and eliminates Fas-positive lymphocytes, resulting in the down-regulation of immune responses. FasL has also been detected in tissues other than lymphoid cells. We investigated the expression and function of FasL on human colon cancer cells. FasL mRNA was detected by RT-PCR in all six colon cancer cell lines tested and was not found on fibroblasts. FasL protein was detected in DLD-1, LoVo, HCT-116 and RPMI 4788 cells by immunohistochemical staining. DLD-1, LoVo and WiDr were cytotoxic against mouse T lymphoma cells which were transfected with human Fas receptor cDNA. The cytotoxicity was significantly enhanced by phorbol 12-myristate 13-acetate (PMA) and ionomycin. Our data suggest that the FasL expressed in human colon cancer cells may be regulated by endogenous factors in the microenvironment of the host and facilitates the escape from the host immune system.

Apoptosis↗
PubMed1998

[Color M-mode Doppler analysis of left ventricular inflow in pediatric patients].

This study evaluated the clinical usefulness of analyzing left ventricular (LV) filling by color M-mode Doppler echocardiography in pediatric patients. The LV-filling patterns of color M-mode Doppler echocardiography were obtained by LV inflow in the apical 4-chamber or long-axis view, and the time difference between the occurrence of peak velocity at the mitral tip and in the apical region (M-AP) was calculated. The peak velocity at each depth was determined by adequate selection of the Nyquist limit by shifting the zero point after freezing the color M-mode. LV volume and posterior wall motion velocity were obtained simultaneously. The catheter-derived data were compared with echo-derived data in 7 patients (mean age 12.0 years). The M-AP correlated positively with the time constant of LV relaxation (tau; r = 0.83, p < 0.05), pulmonary capillary wedge pressure (r = 0.83, p < 0.05), and negatively with peak diastolic posterior wall motion velocity (r = -0.78, p < 0.05). The M-AP was compared with other echo-derived data between Group N (35 children with normal cardiac function, mean age 4.3 years) and Group F (12 children with LV ejection fraction less than 40%, mean age 9.5 years). The M-AP was significantly longer in Group F (53.3 +/- 14.0 vs 116.5 +/- 30.5 msec; p < 0.001), but there was no significant difference in the E/A or deceleration time of E between the 2 groups. In Group N, the E/A correlated to LV end-diastolic volume and heart rate, but the M-AP showed no correlation. In Group F, the M-AP correlated with the percentages of normal LV end-diastolic volume (r = 0.76, p < 0.01) and LV ejection fraction (r = -0.58, p < 0.05). The M-AP was not influenced by LV size or heart rate and could easily differentiate normal heart from failing heart, and thus this is a useful parameter for evaluating diastolic function in pediatric patients.

Adolescent↗
PubMed1997

Nicorandil reduces myocardial infarct size by opening the K(ATP) channel in rabbits.

UNLABELLED: We examined whether nicorandil reduces myocardial infarct size (1) when administered before ischemia, and (2) when administered before reperfusion, and whether (3) infarct size is influenced by the plasma nicorandil concentration and the opening of the K(ATP) channel. Anesthetized open-chest Japanese white male rabbits were subjected to a 30 min coronary occlusion (ischemia) and a 48 h reperfusion in the following six groups; Group 1 (n=9): control group, Group 2 (n=9): pre-ischemia to post-reperfusion group (nicorandil 10 microg/kg/min, i.v.), Group 3 (n=7): pre-ischemia to post-reperfusion+glibenclamide group (glibenclamide 0.3 microg/kg, i.v.+nicorandil 10 microg/kg/min, i.v.), Group 4 (n=8): pre-reperfusion to post-reperfusion group (nicorandil 10 microg/kg/min, i.v.), Group 5 (n=8): pre-ischemia low-dose group (nicorandil 10 microg/kg/min for 5 min i.v.), Group 6 (n=7): pre-ischemia high-dose group (nicorandil 100 microg/kg/min for 5 min i.v.). The plasma nicorandil concentrations were measured from blood samples taken immediately before the ischemia. After the 48 h reperfusion, the size of the infarct was measured histologically with immunohistochemical actin staining and expressed as a percentage of the area at risk. RESULTS: Infarct sizes were as follows; Group 1 (control): 41.0+/-3.5%, Group 2: 31.3+/-2.0% (P<0.05 vs. control), Group 3: 40.9+/-3.4%, Group 4: 45.2+/-4.4%, Group 5: 35.8+/-3.3%, Group 6: 25.2+/-3.9% (P<0.05 vs. control). Infarct size was inversely correlated with the plasma nicorandil concentrations (y=-0.031x+41.0, r=0.65, P<0.05). CONCLUSIONS: The pre-ischemic but not post-ischemic administration of nicorandil reduced the size of myocardial infarct by opening the K(ATP) channels, and this effect was dependent on the plasma nicorandil concentrations immediately before the ischemia induced in rabbits.

Analysis of Variance↗
PubMed1997

Cloning and characterization of the human Calmegin gene encoding putative testis-specific chaperone.

The putative chaperone Calmegin is required for sperm fertility in mouse and the relevance of the gene to certain cases of human male infertility has been suggested. In the present paper, we have isolated and characterized the human homolog cDNA of the mouse germ cell-specific Calmegin. The entire coding region of the human cDNA showed 80% identity with the previously reported mouse Calmegin. The predicted amino acid sequence showed strong conservation of the two sets of internal repetitive sequences (Ca2+ binding motif), and the hydrophilic COOH terminus, which corresponds to the putative endoplasmic reticulum (ER) retention motif. Our finding will support diagnosis of male infertility. Northern blotting analysis of various human tissues showed that the transcript was 3 kb in length and was expressed exclusively in the testis. Using the fluorescence in situ hybridization (FISH) technique, human Calmegin gene was mapped to chromosome 4q28.3-q31.1.

Amino Acid Sequence↗
PubMed1997

cDNA cloning and functional analysis of p44.5 and p55, two regulatory subunits of the 26S proteasome.

We have employed cDNA cloning to deduce the complete primary structures of p44.5 and p55, two subunits of PA700, a 700-kDa multisubunit regulatory complex of the human 26S proteasome. These polypeptides consist of 422 and 456 amino acids with calculated molecular masses of 47463 and 52903, and isoelectric points of 6.06 and 7.56, respectively. Computer-assisted homology analysis revealed high sequence similarities of p44.5 and p55 with yeast proteins whose functions are yet unknown. Disruption of the yeast genes, termed NAS4 and NAS5 (non-ATPase subunits 4 and 5), resulted in lethality, indicating that each of the two subunits is essential for proliferation of yeast cells.

Amino Acid Sequence↗
PubMed1997

Stimulation of cell-surface urokinase-type plasminogen activator activity and cell migration in vascular endothelial cells by a novel hexapeptide analogue of neurotensin.

To investigate if neurotensin (NT) could induce activation of urokinase-type plasminogen activator (uPA) in vascular endothelial cells, we utilized the acetyl-NT (8-13) analogue, TJN-950, in which the C-terminal leucine is reduced to leucinol. TJN-950 inhibited the binding of 125I-NT to membranes of newborn rat brains and of COS-7 cells transfected with rat NT receptor cDNA, but at 10(4) higher doses than NT (8-13). However, TJN-950 was as effective as NT in inducing the fibrinolytic activity in bovine vascular aortic and human umbilical vein endothelial cells, and enhanced the migration of vascular endothelial cells. Moreover, administration of TJN-950 induced neovascularization in the rat cornea in vivo. TJN-950 had no effect on expression of uPA, plasminogen activator inhibitor-1 or uPA receptor mRNA. The binding of 125I-TJN-950 to cell membranes was blocked by unlabeled uPA and TJN-950, but not the amino-terminal or 12-32 fragment of uPA. TJN-950 may enhance uPA activity in vascular endothelial cells by interacting with the uPA receptor, resulting in induction of angiogenesis.

Animals↗
PubMed1997

Enhancement of synaptic transmission by HPC-1 antibody in the cultured hippocampal neuron.

To clarify the function of HPC-1/syntaxin 1A in the mammalian central synapse, the effects of intracellularly applied antibody on the synaptic transmission were examined at the autapse of the cultured rat hippocampal neuron. Intracellularly applied antibody against HPC-1/syntaxin 1A (IgG, 0.3 mg ml(-1)) during whole-cell recording enhanced the autaptic excitatory postsynaptic current (EPSC). Pre-immune IgG (0.3 mg ml(-1)) showed no effect. The amplitude-distribution of an asynchronous EPSC was not affected by administration of this antibody, indicating that the increase in the amplitude of the evoked EPSC was attributable to an increase in transmitter release from the presynaptic terminal HPC-1/syntaxin 1A could be involved in suppressing as well as facilitating process of the exocytosis at the mammalian central synapse.

Animals↗
PubMed1997

Novel combination therapy for human colon cancer with adenovirus-mediated wild-type p53 gene transfer and DNA-damaging chemotherapeutic agent.

Alteration of the wild-type (wt) p53 gene by mutation, deletion or re-arrangement is a major factor in the development of human colon cancer. Recent studies have demonstrated that p53 might be an essential component of the apoptotic pathway triggered by DNA-damaging stimuli such as chemotherapeutic agents and ionizing radiation. We examined the anti-tumor effects of adenovirus-mediated wt-p53 gene transfer in combination with a chemotherapeutic drug on the human colon cancer cell line WiDr, which is homozygous for a mutation in the p53 gene. Treatment with the chemotherapeutic drug cisplatin following infection with a replication-deficient, recombinant adenoviral vector expressing wt-p53 (termed AdCMVp53) significantly suppressed the growth of WiDr cells compared to single treatments alone. To evaluate the in vivo efficacy of AdCMVp53 and cisplatin given sequentially, WiDr cells were inoculated s.c. in nu/nu mice. After 3 days, AdCMVp53 was injected s.c. into the area where tumor cells were implanted, followed by i.p. administration of cisplatin. Analysis of initial growth inhibition at 21 days demonstrated a profound therapeutic cooperativity, though administration of either AdCMVp53 or cisplatin alone was followed only by a slowing of growth. Our results suggest that gene therapy using wt-p53-expressing adenovirus in combination with a chemotherapeutic DNA-damaging drug could be a useful strategy for treating human colon cancer.

Adenoviridae↗
PubMed1997

p53 expression overcomes p21WAF1/CIP1-mediated G1 arrest and induces apoptosis in human cancer cells.

The p21WAF1/CIP1 gene, which encodes a cyclin-dependent kinase inhibitor, may be critical for tumor suppressor gene p53-induced cell cycle arrest. The p53 gene is known to regulate G1 checkpoint, which can either induce G1 arrest or initiate apoptosis. To directly examine the role of p21WAF1/CIP1 in the control of p53 function, we have introduced human p21WAF1/CIP1 gene into a p53-deficient human non-small cell lung cancer cell line H1299 using a p21WAF1/CIP1-expressing adenoviral vector (AdCMVp21). Infection with AdCMVp21 resulted in high levels of p21WAF1/CIP1 expression and significantly suppressed the growth of H1299 cells through the G1 arrest of the cell cycle. In contrast, transient expression of the wild-type p53 gene by a recombinant adenoviral vector (AdCMVp53) in H1299 cells induced apoptotic cell death and resulted in a rapid loss of cell viability. We then examined the effects of combined infection with AdCMVp21 and AdCMVp53 on H1299 cells to explore the dominant function of these molecules. Interestingly, introduction of exogenous p53 overcame p21WAF1/CIP1-mediated cell cycle arrest at G1 and induced apoptosis, although viral-transduced p21WAF1/CIP1 expression level was unaffected. These observations suggest that p53 expression converts a p21WAF1/CIP1-mediated growth arrest into apoptosis. The result was repeated with two additional human colon adenocarcinoma cell lines with the different p53 status, mutant p53-expressing DLD-1 and wild-type p53-expressing LoVo, suggesting that this phemonenon is a general event among human cancer cells. Thus, p53-mediated apoptotic pathway is dominant over the growth arrest pathway, indicating that p53 may be an essential upstream mediator of p21WAF1/CIP1 in the regulation of a cell process leading either to growth arrest or to apoptotic suicide.

Apoptosis↗
PubMed1997

Isolation and expression of a cDNA for human brain fatty acid-binding protein (B-FABP).

We have isolated and sequenced a novel 754-bp human fetal brain cDNA encoding a fatty acid-binding protein (FABP). The cDNA contains an open reading frame of 396 nucleotides (132 amino acids). Northern analysis revealed small amounts of a 1.2-kb transcript in adult human brain and a shorter transcript in skeletal muscle, but no message was detected in other tissues examined. On the other hand, it was abundantly expressed in fetal brain but not in fetal lung, liver or kidney tissues. The elevated level of transcript at immature stages and its subsequent decline In adult brain indicate that the encoded protein may be essential for development of the human brain.

Adult↗
PubMed1997

p32 protein, a splicing factor 2-associated protein, is localized in mitochondrial matrix and is functionally important in maintaining oxidative phosphorylation.

Human p32, originally cloned as a splicing factor 2-associated protein, has been reported to interact with a variety of molecules including human immunodeficiency virus Tat and complement 1q (C1q). p32 protein is supposed to be in the nucleus and on the plasma membrane for the association with human immunodeficiency virus Tat and C1q, respectively. None of the interactions, however, is proven to have a physiological role. To investigate the physiological function of p32, we determined the intracellular localization of p32. The fractionation of cells, fluorescent immunocytochemistry, and electron microscopic immunostaining show that p32 is exclusively localized in the mitochondrial matrix. We cloned a Saccharomyces cerevisiae homologue of human p32 gene, referred to yeast p30 gene. The yeast p30 protein is also localized in the mitochondrial matrix. The disruption of the p30 gene caused the growth retardation of yeast cells in a glycerol medium but not in a glucose medium, i.e. the impairment of the mitochondrial ATP synthesis. The growth impairment was restored by the introduction of the human p32 cDNA, indicating that p30 is a functional yeast counterpart of human p32. Taken together, both p32 and p30 reside in mitochondrial matrix and play an important role in maintaining mitochondrial oxidative phosphorylation.

Amino Acid Sequence↗