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Biomedical subjects

H Fujii

Publications and source records attributed to H Fujii.

At least 73 records · Page 4Linked to original sources

A new liquid embolic material for liver tumors.

PURPOSE: To evaluate the feasibility of a new liquid embolic material, Onyx, for treating liver tumors. MATERIAL AND METHODS: Onyx is a mixture of 6% (w/v) ethylene-vinyl-alcohol copolymer dissolved in anhydrous dimethyl sulfoxide (DMSO) with 28% (w/v) tantalum powder. In addition to 6% Onyx, we also tried 4%, 2% and 1% solutions, prepared by adjusting the amount of DMSO. We used 15 white rabbits with liver tumors created by percutaneous injection of VX2 tumor cells. In 4 groups with 3 rabbits in each, the liver arteries were embolized with 6%, 4%, 2% and 1% Onyx, respectively, and in 3 rabbits DMSO alone was injected. The injections were performed just proximal to the bifurcation of the proper hepatic artery, followed by celiac arteriography. Post mortem, the livers were examined by soft-tissue radiography, and liver-tissue section microscopy. RESULTS: The maximum number of arterial branching points passed by embolic material in either the right or left hepatic arteries was 11, 15 and 16, for 6%, 4% and 2% Onyx, respectively, but was non-measurable for 1% Onyx. Minimum diameters of arteries reached by 6%, 4%, 2% and 1% Onyx in tumorous areas were 40 microm, 35 microm, 20 microm and 10 microm, respectively, and in non-tumorous areas 35 microm, 5 microm, 5 microm and 5 microm, respectively. CONCLUSION: This study suggests that Onyx may be feasible for treatment of hepatic tumors.

Animals↗

Long-term results of chronic hemodialysis patients with isolated coronary artery bypass grafting performed by the same surgeon. A comparative study.

BACKGROUND: The aim of this study was to examine the long-term results of isolated coronary artery bypass grafting (CABG) patients who required chronic hemodialysis. METHODS: From May 1990 to June 2000, 23 hemodialysis patients received isolated CABG performed by the same surgeon. Postoperative follow-up was completed with maximum duration of 122 months. RESULTS: Operative deaths (n=2) were due to acute circulatory failure related to hemodialysis. The most frequent cause of late deaths (n=10) was infection. Five (50%) patients died of sepsis, and 80% of sepsis was caused by leg infection associated with arteriosclerosis obliterans. There were 6 late cardiac events including 3 cardiac deaths. The actual survival rates 1, 3, 5 and 7 years after CABG were 68.6%, 42.5%, 35.4% and 35.4%, respectively. And the actual cardiac event free rates 1, 3, 5 and 7 years after CABG were 77.6%, 77.6%, 46.6% and 46.6%, respectively. Operative mortality (p=0.019), long-term survival (p<0.001) and cardiac event free rate (p=0.002) were significantly poorer in hemodialysis patients than in non-hemodialysis patients. However, the long-term survival rate of our hemodialysis patients receiving isolated CABG was almost similar to that in dialysis patients without CABG. The etiology of chronic renal failure did not significantly affect long-term RESULTS. Using internal thoracic artery graft significantly (p=0.02) decreased the late cardiac event in hemodialysis patients, although it did not improve late survival. CONCLUSIONS: Primary CABG followed by aggressive re-intervention have the benefit of preventing late cardiac death in hemodialysis patients. However, prevention of sepsis and treatment of arteriosclerosis obliterans are important for improving the late survival in hemodialysis patients receiving isolated CABG.

Aged↗

Observation of the decay B --> Kl+l-.

We report a search for the flavor-changing neutral current decay B-->K(*)l+l- using a 29.1 fb(-1) data sample accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. We observe the decay process B-->Kl+l-(l = e, mu), for the first time, with a branching fraction of B(B-->Kl+l-) = (0.75(+0.25)(-0.21)+/-0.09)x10(-6).

Journal Article↗

Accumulative increase of loss of heterozygosity from leukoplakia to foci of early cancerization in leukoplakia of the oral cavity.

BACKGROUND: Oral leukoplakia is a premalignant lesion, but the genetic changes in the foci of early cancerization in leukoplakia have not been studied. METHODS: Loss of heterozygosity (LOH) was successively investigated in 13 cases in the leukoplakia and foci of early cancerization in the same leukoplakia. The authors microdissected both lesions, and 33 microsatellite markers at 14 chromosomal loci were examined by a polymerase chain reaction-based microsatellite assay. RESULTS: Loss of heterozygosity detected in the leukoplakia was identically observed in the foci of early cancerization in leukoplakia in 11 of 13 cases, and in 2 cases allelic divergence was observed. Loss of heterozygosity occurred even in the leukoplakia with high frequency at 9p21 (66.7%), 3p14-25 (61.5%), 4q31-32 (45.5%), and 17p12-14 (44.4%). The foci of early cancerization in leukoplakia showed accumulative increase of LOH at these and other loci. Loss of heterozygosity at 5q21-23 was found to have significant difference between the leukoplakia and the foci of early cancerization in leukoplakia (P = 0.0137, Fisher exact test). Microsatellite instability was observed at low level in three cases. The mean value of fractional allelic loss in the leukoplakia differed significantly from that in the foci of early cancerization in leukoplakia (0.02 < P < 0.05, Student t test). CONCLUSIONS: The high incidence of LOH in the leukoplakia indicated premalignant potentiality of this lesion and that accumulative increase of LOH from leukoplakia to foci of early cancerization in leukoplakia might play a significant role in the cancerization of leukoplakia. Comparison of LOH between the leukoplakia and the foci of early cancerization in leukoplakia suggested that these two lesions were derived from a common clone.

Aged↗

Observation of B --> J/psi K(1)(1270).

We report the first observation of the exclusive decay process B-->J/psi K(1)(1270) using a sample of 11.2M BB macro meson pairs collected in the Belle detector at the KEKB asymmetric energy e(+)e(-) collider. We measure branching fractions of B[B(0)-->J/psi K(0)(1)(1270)] = (1.30+/-0.34+/-0.32) x 10(-3) and B[B(+)-->J/psi K(+)(1)(1270)] = (1.80+/-0.34+/-0.39) x 10(-3), where the first error is statistical and the second is systematic. These modes constitute approximately 15% of the total number of B-->J/psi X decays. No evidence is seen for B-->J/psi K(1)(1400) and we set an upper limit for this branching fraction.

Journal Article↗

Characterization of the 13q14 tumor suppressor locus in CLL: identification of ALT1, an alternative splice variant of the LEU2 gene.

Chromosome 13q14 deletions constitute the most common genetic abnormality in chronic lymphocytic leukemia (CLL). To identify the putative tumor suppressor gene targeted by 13q14 genomic loss, we completely sequenced and characterized a segment of 790 kb at 13q14 spanning the minimal region of loss in CLL. Transcribed sequences in the region were identified through database homology searches and exon-prediction analysis. Two-hundred kb at the centromeric end of the sequence contain five CpG islands, three previously identified genes LEU5/RFP2, LEU2, and LEU1, seven of seven EST clusters composed of >10 ESTs, and a large number of predicted exons. Homology searches against the mouse EST database have allowed us to identify a highly conserved alternative first exon of the LEU2 gene, giving rise to a novel transcript, ALT1 (GenBank accession no. AF380424), which originates within a G+C region in the vicinity of the D13S272 marker. Two novel 3' exons of LEU2 were also identified and are present in both LEU2 and ALT1 transcripts. However, we have not identified any mutations in leukemia cases, or alterations in expression of mRNAs in the region, that might directly implicate these mRNAs in the pathology of CLL. The centromeric end of the sequence, where all reported genes are located, contains twice the expected amount of ALU repeats, whereas the telomeric end is LINE1 rich and contains four LINE1 elements longer than 4 kb, including two full-length LINE1 sequences. This feature of the sequence may favor the occurrence of chromosomal rearrangements and may confer instability to the region, resulting in deletions that may inactivate an as yet unidentified tumor suppressor.

Alternative Splicing↗

Observation of Cabibbo suppressed B --> D(*)K- decays at Belle.

We report observations of the Cabibbo suppressed decays B-->D((*))K- using a 10.4 fb(-1) data sample accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. We find that the ratios of Cabibbo suppressed to Cabibbo favored branching fractions are B(B--->D0K-)/B(B--->D0pi(-)) = 0.079+/-0.009+/-0.006, B(B(0)-->D+K-)/B(B(0)-->D+pi(-)) = 0.068+/-0.015+/-0.007, B(B--->D(*0)K-)/B(B--->D(*0)pi(-)) = 0.078+/-0.019+/-0.009, and B(B(0)-->D(*+)K-)/B(B(0)-->D(*+)pi(-)) = 0.074+/-0.015+/-0.006. These are the first observations of the B-->D+K-, D(*0)K-, and D(*+)K- decay processes.

Journal Article↗

Tumor heterogeneity in small hepatocellular carcinoma: analysis of tumor cell proliferation, expression and mutation of p53 AND beta-catenin.

Most hepatocellular carcinomas (HCCs) first occur as well-differentiated HCCs, from which poorly differentiated HCC cells develop because of dedifferentiation. In this study, we try to clarify the changes of dedifferentiation and cell proliferative activity and their relationship in small HCCs (less than 3.0 cm in diameter) and try to learn the mechanism of these changes by analysing the expressions and genetic changes of proliferation-related genes p53 and beta-catenin. Of 41 surgically resected small HCCs, 11 were identified to have tumor heterogeneity. DNA from the 11 small HCCs, consisting of 29 intratumoral lesions and 11 noncancerous liver tissues adjacent to HCCs, was extracted from paraffin embedded tissue sections. Exons 5-8 of p53 gene and exon 3 of beta-catenin gene were amplified by polymerase chain reaction and analyzed by direct sequence. The serial sections were also immunostained by anti-Ki-67, p53 and beta-catenin antibody. Immunohistochemistry showed that the p53 overexpression was significantly related to the proliferative activities as evaluated by Ki-67 immunostaining and to the histological differentiation. The expression of beta-catenin was found to be heterogeneously distributed not only in various histological grades of the same tumor but also in areas of the same histological grade. p53 and beta-catenin gene mutations were detected in 1 tumor respectively, both of which were second primary HCCs and also recurred later. The p53 mutation showed the same mutation pattern in heterogeneous subpopulations. beta-catenin mutation was detected only in the less differentiated lesion but not in the well-differentiated lesion of tumor. In conclusion, our findings suggest that there was histological heterogeneity in small but established HCC, which was accompanied by increased proliferative activity and p53 overexpression. The overexpression of beta-catenin may be related to the proliferative activity and dedifferentiation of HCC.

Aged↗

Observation of large CP violation in the neutral B meson system.

We present a measurement of the standard model CP violation parameter sin2 phi(1) based on a 29.1 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is fully reconstructed as a J/psi K(S), psi(2S)K(S), chi(c1)K(S), eta(c)K(S), J/psi K(L), or J/psi K(*0) decay and the flavor of the accompanying B meson is identified from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we determine sin2 phi(1) = 0.99+/-0.14(stat)+/-0.06(syst). We conclude that we have observed CP violation in the neutral B meson system.

Journal Article↗

Defective expression of the interleukin-2/interleukin-15 receptor beta subunit leads to a natural killer cell-deficient form of severe combined immunodeficiency.

Development of T and natural killer (NK) cells is critically dependent on cytokine signaling, and defects in cytokine receptor complex subunits have been shown to result in severe combined immunodeficiency (SCID) syndromes in humans and in murine models. An infant boy had typical clinical features of SCID and was found to lack NK cells in his peripheral circulation. Molecular analysis did not reveal abnormalities in his gammac or JAK-3 genes, and he was investigated for defects in the interleukin-15 (IL-15) receptor complex because functional IL-15 signaling is essential for NK cell development. Expression of the IL-2R/IL-15Rbeta chain was significantly reduced in the patient's peripheral blood mononuclear cells (PBMCs) by immunoblot, flow cytometry, and Northern blot analysis. Furthermore, IL-2 stimulation of PBMCs showed only minimal tyrosine phosphorylation of JAK-3. These data demonstrate that defects in IL-2R/1L-15Rbeta expression can lead to a unique NK-deficient SCID immunophenotype. (Blood. 2001;98:877-879)

Exons↗

A role for highly conserved carboxylate, aspartate-140, in oxygen activation and heme degradation by heme oxygenase-1.

Heme oxygenase (HO) catalyzes the oxygen-dependent degradation of heme to biliverdinIXalpha, CO, and free iron ion via three sequential monooxygenase reactions. Although the distinct active-site structure of HO from cytochrome P450 families suggests unique distal protein machinery to activate molecular oxygen, the mechanism and the key amino acid for the oxygen activation have not been clear. To investigate the functionality of highly conserved polar amino acids in the distal helix of HO-1, we have prepared alanine mutants: T135A, R136A, D140A, and S142A, and found drastic changes in the heme degradation reactions of D140A. In this paper, we report the first evidence that D140 is involved in the oxygen activation mechanism in HO-1. The heme complexes of HO mutants examined in this study fold and bind heme normally. The pK(a) values of the iron-bound water and autoxidation rates of the oxy-form are increased with R136A, D140A, and S142A mutations, but are not changed with T135A mutation. As the wild-type, T135A, R136A, and S142A degrade heme to verdohemeIXalpha with H(2)O(2) and to biliverdinIXalpha with the NADPH reductase system. On the other hand, D140A heme complex forms compound II with H(2)O(2), and no heme degradation occurs. For the NADPH reductase system, the oxy-form of D140A heme complex is accumulated in the reaction, and only 50% of heme is degraded. The stopped flow experiments suggest that D140A cannot activate iron-bound dioxygen and hydroperoxide properly. To investigate the carboxylate functionality of D140, we further replaced D140 with glutamic acid (D140E), phenylalanine (D140F), and asparagine (D140N). D140E degrades heme normally, but D140N shows reactivity similar to that of D140A. D140F loses heme degradation activity completely. All of these results indicate that the carboxylate at position 140 is essential to activate the iron-bound dioxygen and hydroperoxide. On the basis of the present findings, we propose an oxygen activation mechanism involving the hydrogen-bonding network through the bridging water and D140 side chain.

Animals↗

Human cutaneous fatty acid-binding protein induces metastasis by up-regulating the expression of vascular endothelial growth factor gene in rat Rama 37 model cells.

Human cutaneous fatty acid-binding protein (C-FABP) gene is capable of inducing the metastatic phenotype when overexpressed in nonmetastatic rat Rama 37 cells. However, the mechanism of how it induces metastasis is not clear. Northern and slot blot analyses revealed that expression of the endogenous vascular endothelial growth factor (VEGF) gene was increased by 3.8-5.2-fold in the C-FABP-transfected cells (pSV-CFABP-R37) and in their metastatic sublines (e.g., Met-1) when compared with that in the nonmetastatic control transfectant pSV-R37 cells generated by transfection of only plasmid DNA. Higher levels of VEGF immunoreactive protein were also secreted from the malignant C-FABP-expressing cells. Reverse transcription-PCR detected two VEGF transcript isoforms, VEGF(164) and VEGF(188), in both the nonmetastatic control transfectant pSV-R37 cells and the malignant metastatic Met-1 cells. Chick chorioallantoic membrane assays showed that the conditioned medium of the control pSV-R37 cells possessed only very weak angiogenic activity, whereas conditioned media from the metastatic C-FABP transfectants and their sublines were strongly angiogenic and could be inhibited by antibodies to VEGF. Transfection of VEGF(164) cDNA in an expression vector into nonmetastatic Rama 37 cells produced a cell clone (R37-VEGF-2) that expressed high levels of VEGF. Inoculation of R37-VEGF-2 cells into syngeneic Wistar Furth rats produced metastases in a significant number (Fisher's exact test, P < 0.01) of animals (18 of 31 animals), whereas the control, vector alone-transfected R37-PSV cells produced no metastases (0 of 30 animals). Immunocytochemical methods demonstrated a strong positive staining for VEGF and an increased microvessel density in the primary tumors produced from PSV-VEGF-2 cells in comparison with tumors produced from control transfectants. Immunocytochemical staining for factor VIII detected a 3.5-fold increase in microvessel density of the primary tumors produced by PSV-VEGF-2 cells when compared with that of the primary tumors developed from the control pSV-R37 cells. Therefore, we suggest that overexpression of the C-FABP gene in the original transfectants induces metastasis through up-regulation of expression of the VEGF gene in this rat Rama 37 model system, and thus VEGF may play a crucial role in this particular metastatic cascade.

Animals↗

Measurement of B(0)(d)-B_(0)(d) mixing rate from the time evolution of dilepton events at the upsilon(4S).

We report a determination of the B(0)(d)-&B_(0)(d) mixing parameter Deltam(d) based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 fb(-1) data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing Deltam(d) as a free parameter. Using both muons and electrons, we obtain Deltam(d) = 0.463+/-0.008 (stat)+/-0.016 (syst) ps(-1). This is the first determination of Deltam(d) from time evolution measurements at the Upsilon(4S). We also place limits on possible CPT violations.

Journal Article↗

The pharmacological profile of delta opioid receptor ligands, (+) and (-) TAN-67 on pain modulation.

We designed the nonpeptidic highly selective delta opioid receptor agonist on the basis of message address concept and the accessory site theory and synthesized (+/-) TAN-67. In spite of highly potent agonistic activity in in vitro assay, (+/-) TAN-67 (racemate) afforded a weak antinociceptive effect in the mouse tail-flick test. This result led us to separate (+/-) TAN-67 to optical pure compounds, (+) and (-) TAN-67. An i.t.-treatment with (-) TAN-67 produced profound antinociceptive effects through specifically acting on delta1 receptors. Unlike (-) TAN-67, i.t.-administered (+) TAN-67 displayed dose-related nociceptive behaviors such as scratching, biting and licking. The effect of (+) TAN-67 was blocked by i.t.-treatment with NTI (delta receptor antagonist) and (-) TAN-67 (delta1 receptor agonist), but not by morphine (mu receptor agonist). The mechanisms involved in spinal pain modulation induced by (+) and (-) TAN-67 were also described.

Analgesics↗

Cloning and characterization of CLLD6, CLLD7, and CLLD8, novel candidate genes for leukemogenesis at chromosome 13q14, a region commonly deleted in B-cell chronic lymphocytic leukemia.

Chromosome 13q14 deletions constitute the most common structural aberration in B-cell chronic lymphocytic leukemia (B-CLL). We constructed a high-resolution physical map covering the critical deleted region in B-CLL at 13q14 and flanking sequences. The order and position of both genomic markers and known genes were determined precisely. Three novel genes, CLLD6, CLLD7, and CLLD8, were isolated and characterized. The predicted protein sequence of CLLD6 revealed no homology with known proteins. However, both CLLD7 and CLLD8 predicted proteins contain known functional domains. CLLD7 has both an RCC1 and a BTB domain, and could thus be involved in cell cycle regulation by chromatin remodeling. CLLD8 contains a methyl-CpG binding, a preSET and a SET domain, suggesting that CLLD8 might be associated with methylation-mediated transcriptional repression. Mutation analysis of hematopoietic tumor cell lines and B-CLL tumor samples revealed no point mutations within the coding region of these three novel genes. The functional domains present within CLLD7 and CLLD8 suggest that the proteins may be involved in critical cellular processes such as cell cycle and transcriptional control and could therefore be directly or indirectly involved in leukemogenesis.

Amino Acid Sequence↗

Measurement of the CP violation parameter sin2 phi(1) in B(0)(d) meson decays.

We present a measurement of the standard model CP violation parameter sin2 phi(1) (also known as sin2beta) based on a 10.5 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) collider. One neutral B meson is reconstructed in the J/psiK(S), psi(2S)K(S), chi(c1)K(S), eta(c)K(S), J/psiK(L), or J/psipi(0) CP-eigenstate decay channel and the flavor of the accompanying B meson is identified from its charged particle decay products. From the asymmetry in the distribution of the time interval between the two B-meson decay points, we determine sin2 phi(1) = 0.58(+0.32)(-0.34)(stat)+0.09-0.10(syst).

Journal Article↗