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T Fukushima

Publications and source records attributed to T Fukushima.

At least 37 records · Page 2Linked to original sources
PubMed2004

T-bet upregulation and subsequent interleukin 12 stimulation are essential for induction of Th1 mediated immunopathology in Crohn's disease.

BACKGROUND AND AIMS: Many lines of evidence suggest that T helper cell type 1 (Th1) immune responses predominate in Crohn's disease (CD). Recently, a novel transcription factor T-box expressed in T cells (T-bet) has been reported as the master regulator of Th1 development. This study was designed to investigate the role of T-bet and proinflammatory cytokines in Th1 mediated immunopathology in CD. MATERIALS: CD4+ lamina propria mononuclear cells (LPMCs) were isolated from surgically resected specimens (CD, n = 10; ulcerative colitis (UC), n = 10; normal controls (NL), n = 5). METHODS: (1) T-bet expression of CD4+ LPMCs was examined by quantitative real time polymerase chain reaction and western blotting. (2) T-bet expression of LPMCs stimulated by interleukin (IL)-12/IL-18 was analysed by western blotting. (3) Interferon gamma (IFN-gamma) production and T-bet expression of CD4+ peripheral blood mononuclear cells (PBMCs) were examined with or without stimulation by anti-CD3/CD28 monoclonal antibodies and/or IL-12. RESULTS: (1) T-bet expression of CD4+ LPMCs was increased in CD compared with UC and NL. (2) Synergistically, augmentation of IFN-gamma production by IL-12/IL-18 was independent of T-bet expression in LPMCs. (3) T-bet was induced by T cell receptor stimulation in CD4+ PBMCs. T-bet induction correlated with IFN-gamma production and with augmentation of surface expressed IL-12 receptor beta2. CONCLUSIONS: T-bet induction by antigenic stimulation and subsequent stimulation by macrophage derived IL-12/IL-18 are important for establishing Th1 mediated immunopathology in CD.

Adult↗
PubMed2003

Antibacterial characteristics of newly developed amphiphilic lipids and DNA-lipid complexes against bacteria.

The purpose of this study was to investigate the antibacterial activity of newly developed amphiphilic lipids and DNA/lipid complexes against two types of oral bacteria and two types of hospital infection bacteria. Nine amphiphilic lipids were quantitatively prepared from the reaction of n-alkyl alcohol, alpha-amino acids, and p-toluenesulfonic acid. Nine DNA-lipid complexes were prepared by the simple mixing of DNA and amphiphilic lipids. The DNA-lipid complexes were insoluble in water. The antibacterial activity of lipids and DNA-lipid complexes against Porphyromonas gingivalis, Streptococcus mutans, Staphylococcus aureus, and Pseudomonas aeruginosa were evaluated by the disk-diffusion method. Seven artificial lipids showed antibacterial behavior; in particular, the lipids prepared from n-decyl alcohol and glycine and from n-decyl alcohol and L-alanine showed antibacterial activity against the four bacterial strains used in this study. On the other hand, the lipids of glutamic acid derivatives did not show any antibacterial activity against the four bacteria strains except for the lipid with an n-octyl group. Five DNA-lipid complexes also had an antibacterial effect. The complex prepared from DNA and glycine decyl ester p-toluenesulfonic acid salt exhibited antibacterial activity against the four types of bacteria strains. In this study it was found that lipids and DNA-lipid complexes with a mono-decyl group or a mono-dodecyl group have more favorable antibacterial activity.

Anti-Bacterial Agents↗
PubMed2003

Essential Bacillus subtilis genes.

To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among approximately 4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from bacteria with small genomes. Unexpectedly, most genes involved in the Embden-Meyerhof-Parnas pathway are essential. Identification of unknown and unexpected essential genes opens research avenues to better understanding of processes that sustain bacterial life.

Bacillus subtilis↗
PubMed2003

Dual mutations in the AML1 and FLT3 genes are associated with leukemogenesis in acute myeloblastic leukemia of the M0 subtype.

Point mutations of the transcription factor AML1 are associated with leukemogenesis in acute myeloblastic leukemia (AML). Internal tandem duplications (ITDs) in the juxtamembrane domain and mutations in the second tyrosine kinase domain of the Fms-like tyrosine kinase 3 (FLT3) gene represent the most frequent genetic alterations in AML. However, such mutations per se appear to be insufficient for leukemic transformation. To evaluate whether both AML1 and FLT3 mutations contribute to leukemogenesis, we analyzed mutations of these genes in AML M0 subtype in whom AML1 mutations were predominantly observed. Of 51 patients, eight showed a mutation in the Runt domain of the AML1 gene: one heterozygous missense mutation with normal function, five heterozygous frameshift mutations and two biallelic nonsense or frameshift mutations, resulting in haploinsufficiency or complete loss of the AML1 activities. On the other hand, a total of 10 of 49 patients examined had the FLT3 mutation. We detected the FLT3 mutation in five of eight (63%) patients with AML1 mutation, whereas five of 41 (12%) without AML1 mutation showed the FLT3 mutation (P=0.0055). These observations suggest that reduced AML1 activities predispose cells to the acquisition of the activating FLT3 mutation as a secondary event leading to full transformation in AML M0.

Cell Transformation, Neoplastic↗
PubMed2003

Mutational analysis of TGF-beta type II receptor, Smad2, Smad3, Smad4, Smad6 and Smad7 genes in colorectal cancer.

Transforming growth factor-beta(TGF-beta) is known to play an important role in controlling embryonal development, cell proliferation and homeostasis. The purpose of this study is to elucidate the involvement of the TGF-beta pathway in colorectal carcinogenesis. DNA was extracted from 100 patients with colorectal cancer. Then, all coding regions of the TGF-beta type II receptor (TRII) and the genes for Smad2, Smad3, Smad4, Smad6, and Smad7 were analyzed by PCR-SSCP and direct sequencing. Also, a LOH analysis of 18q21, where the Smad2 and Smad4 genes are located, was performed. We detected 11 cases of frameshift mutation in the TRII gene (11%) and 5 cases of point mutations in the Smad4 gene (5.0%); LOH at 18q21 was detected with 33% frequency. No abnormalities were found in the genes for Smad2, Smad3, Smad6, and Smad7. These results suggest that the abnormalities of TRII and Smad4 play an important role inhibiting TGF-beta signaling in colorectal carcinogenesis.

Base Sequence↗
PubMed2002

Estrogen induces a rapid increase of calcium-calmodulin-dependent protein kinase II activity in the hippocampus.

Molecular genetics experiments using gene targeting and transgenic technology demonstrated the importance of alpha-calcium-calmodulin-dependent protein kinase II (alphaCaMKII) in long-term potentiation (LTP) and memory. Little information is available though on how CaMKII activity may be regulated in vivo. We show that estradiol benzoate activates CaMKII in a dose and time-dependent manner in mouse hippocampus after 30 min stimulation. The effect of estrogen is via a very rapid nongenomic mechanism that is blocked in vitro in hippocampal primary neurons by the pure estrogen receptor antagonist, ICI 182,780. These results suggest that estrogen action in the hippocampus is linked to CaMKII activation.

Animals↗
PubMed2002

Video-assisted parathyroidectomy.

A parathyroid tumor is not larger than other tumors, so minimally invasive surgery has long been a major focus of parathyroid surgeons. Improving endoscopic instruments has facilitated the recent changes in approaches to parathyroid surgery. Endoscopic parathyroidectomy is developed in a totally closed space with CO2 gas insufflation. This method has a risk of complications, such as extensive emphysema or hypercarbia. Minimally invasive video-assisted parathyroidectomy (MIVAP) has greater safety, low cost, easy procedure and flexibility in changing the working space including conversion to open method when compared with endoscopic parathyroidectomy. MIVAP can be performed with only a 1-1.5-cm small incision on the neck. MIVAP is indicated in the patient with parathyroid adenoma or renal hyperplasia that is defined preoperatively using ultrasonography and 99mTc-methoxyisobutylisonitrile (MIBI) scan. Furthermore, the radio-guided technique using nuclear navigation after preoperative administered MIBI is being developed. This method is so useful during MIVAP that we combined MIVAP and radio-guided surgery to develop minimally invasive radio-guided and video-assisted parathyroidectomy (MIRVAP). After injection of 600 MBq of MIBI, intraoperative nuclear mapping was performed using a hand-held gamma probe. Then we expected to find swollen parathyroid tumor at surgery when radioactivity at a level relatively higher than background was found. Following this mapping result, MIVAP was started and succeeded. The radio-guided technique is also indicated for open parathyroidectomy (radio-guided open parathyroidectomy, RGOP) in multiglandular disease (MGD) when it was not possible to identify those lesions completely, for instance in asymmetric hyperplasia, such as multiple endocrine neoplasia (MEN) 1. In conclusion, MIVAP is beneficial for minimal invasiveness and cosmesis. Furthermore, radio-guided parathyroidectomy (MIRVAP and RGOP) is more useful and feasible. Improvement of endoscopic instruments and modification of the dose of MIBI administered might facilitate treating more cases by MIRVAP instead of RGOP.

Animals↗
PubMed2002

Induction therapy by frequent administration of doxorubicin with four other drugs, followed by intensive consolidation and maintenance therapy for adult acute lymphoblastic leukemia: the JALSG-ALL93 study.

In order to improve the disappointing prognosis of adult patients with acute lymphoblastic leukemia (ALL), we applied similar induction therapy as that used for acute myeloid leukemia (AML), ie frequent administration of doxorubicin (DOX). DOX 30 mg/m(2) was administered from days 1 to 3 and from days 8 to 10 together with vincristine, prednisolone, cyclophosphamide and L-asparaginase, followed by three courses of consolidation and four courses of intensification. From December 1993 to February 1997, 285 untreated adult patients with de novo ALL were entered. Of 263 evaluable patients (age 15 to 59; median 31), 205 (78%) obtained complete remission (CR). At a median follow-up period of 63 months, the predicted 6-year overall survival (OS) rate of all patients was 33%, and disease-free survival (DFS) rate of CR patients was 30%, respectively. By multivariate analysis, favorable prognostic factors for the achievement of CR were age <40 and WBC <50 000/microl; for longer OS were age <30 and WBC <30 000/microl; and for longer DFS of CR patients were FAB L1 and ALT <50 IU/l. Among 229 patients who had adequate cytogenetic data, 51 (22%) had Philadelphia (Ph) chromosome. Ph-negative chromosome was a common favorable prognostic factor for CR, longer OS and DFS. DFS was not different between early sequential intensification (n = 48) and intermittent intensification (n = 43) during the maintenance phase. Among CR patients under 40 years old, the 6-year survival was not different between the allocated related allo-BMT group (34 patients) and the allocated chemotherapy group (108 patients). However, among patients with Ph-positive ALL, the survival of patients who actually received allo-BMT was superior to that of patients who received chemotherapy (P = 0.046).

Antibiotics, Antineoplastic↗
PubMed2002

A model for predicting sediment-water partition of toxic chemicals in aquatic environments.

In order to investigate the characteristics of sediment-water partition of chemicals in aquatic environments using published data, we developed a model for predicting the sediment-water partition coefficient (Kp) as the sum of sorption to sediment organic matter and sorption to sediment inorganic matter. This model is so successful that the differences between Kp (median for a variety of Japanese water bodies) and pre-Kp (predicted K) are within one order of magnitude in 24 out of 28 chemicals.

Adsorption↗
PubMed2001

Preparation, structure, and amphoteric redox properties of p-phenylenediamine-type dyes fused with a chalcogenadiazole unit.

4,7-Bis(dialkylamino)benzo[c][1,2,5]chalcogenadiazoles are a novel class of organic dyes that undergo reversible two-stage one-electron oxidation as well as one-electron reduction. They exhibit absorption maxima in the long-wavelength region, which are assigned as intramolecular charge transfer bands from the phenylenediamine moiety to the electron-accepting heterocycle. Their redox properties as well as molecular and crystal structures are affected by the alkyl substituents on the amino nitrogen and/or by the chalcogen atom (O, S, Se) in the heterocycle.

Journal Article↗
PubMed2001

Ruthenium-catalyzed hydration of 1-alkynes to give aldehydes: insight into anti-Markovnikov regiochemistry.

The mechanism of the selective conversion of 1-alkynes to aldehydes by hydration was investigated by isolating organic and organometallic byproducts, deuterium-labeling experiments, and DFT calculations. The D-labeled acetylenic hydrogen of 1-alkyne was found exclusively in the formyl group of the resulting aldehydes. After the reaction, the presence of metal-coordinated CO was confirmed. All of the experimental results strongly suggest the involvement of a metal-acyl intermediate with the original acetylenic hydrogen also bound to the metal center as a hydride, with the next step being release of aldehyde by reductive elimination. Theoretical analyses suggest that the first step of the catalytic cycle is not oxidative addition of acetylene C [bond] H or tautomerization of eta(2)-alkyne to a vinylidene complex, but rather protonation of the coordinated 1-alkyne at the substituted carbon to form a metal-vinyl intermediate. This cationic intermediate then isomerizes to Ru(IV)-hydride-vinylidene via alpha-hydride migration of the vinyl group to the metal center, followed by attack of the vinylidene alpha-carbon by OH(-) to give the metal-hydride-acyl intermediate.

Journal Article↗
PubMed2001

Determination of bradykinin in rat urine by coupled-column high pressure liquid chromatography with precolumn derivatization with a water-soluble fluorogenic reagent.

Bradykinin (BK) in rat urine was determined by coupled-column HPLC with precolumn fluorogenic derivatization with a water-soluble reagent, 3-(7-fluoro-2,1,3-benzoxadiazole-4-sulfonamido)benzenesulfonic acid (m-BS-ABD-F). The derivatization of BK with m-BS-ABD-F was completed at 70 degrees C for 100 min and gave only a single peak of BK derivative in addition to the peaks of the blank. The hydrophilicity of the derivatization reagent effectively prevented the adsorption of BK during the sample pretreatment and improved the recovery of BK. Good linearity was shown between the amount of BK spiked in urine (0-10 pmol) and the peak area of the BK derivatives (correlation coefficients >0.999), and the detection limits of the BK derivative were 35 fmol (S/N = 3). The precisions (cv, %) of intra- and interday assay were not more than 5.5% and the accuracies were in the range of 95.3-111% (1 and 5 pmol of BK in urine, n = 3). Although the peak regarded as that of the BK derivative rapidly decreased after incubation at 37 degrees C, addition of urinary kininase inhibitors to the urine samples drastically suppressed the decrease of this peak, confirming that the identified peak was that of the BK derivative. The urinary kinin excretion in male SD rats (9-11 weeks old) determined by the present method was 56.0 +/- 22.1 pg/min/kg (mean +/- SE, n = 5).

Animals↗
PubMed2001

Genetic analysis of the DNA-dependent protein kinase reveals an inhibitory role of Ku in late S-G2 phase DNA double-strand break repair.

Two major complementary double-strand break (DSB) repair pathways exist in vertebrates, homologous recombination (HR), which involves Rad54, and non-homologous end-joining, which requires the DNA-dependent protein kinase (DNA-PK). DNA-PK comprises a catalytic subunit (DNA-PKcs) and a DNA-binding Ku70 and Ku80 heterodimer. To define the activities of individual DNA-PK components in DSB repair, we targeted the DNA-PKcs gene in chicken DT40 cells. DNA-PKcs deficiency caused a DSB repair defect that was, unexpectedly, suppressed by KU70 disruption. We have shown previously that genetic ablation of Ku70 confers RAD54-dependent radioresistance on S-G(2) phase cells, when sister chromatids are available for HR repair. To test whether direct interference by Ku70 with HR might explain the Ku70(-/-)/DNA-PKcs(-/-/-) radioresistance, we monitored HR activities directly in Ku- and DNA-PKcs-deficient cells. The frequency of intrachromosomal HR induced by the I-SceI restriction enzyme was increased in the absence of Ku but not of DNA-PKcs. Significantly, abrogation of HR activity by targeting RAD54 in Ku70(-/-) or DNA-PKcs(-/-/-) cells caused extreme radiosensitivity, suggesting that the relative radioresistance seen with loss of Ku70 was because of HR-dependent repair pathways. Our findings suggest that Ku can interfere with HR-mediated DSB repair, perhaps competing with HR for DSB recognition.

Animals↗
PubMed2001

SH2D1A mutations in Japanese males with severe Epstein-Barr virus--associated illnesses.

X-linked lymphoproliferative disease (XLP), a genetic disorder characterized by immunodeficiency to Epstein-Barr virus (EBV) infection, has been linked to mutations in the SH2D1A gene. To search for the occurrence of SH2D1A mutations in Japan, we performed genetic analysis of the SH2D1A gene in 40 males presenting with severe EBV-associated illnesses, including fulminant infectious mononucleosis, EBV-positive lymphoma, and severe chronic active EBV infection. SH2D1A mutations were detected in 10 of these 40 patients. Five of these 10 cases were sporadic. Patients with SH2D1A mutations displayed severe acute infectious mononucleosis with hyperimmunoglobulin M, hypogammaglobulinemia, and B-cell malignant lymphoma. By contrast, chronic active EBV infection was not associated with SH2D1A mutations. XLP survivors exhibited normal levels of circulating EBV-DNA during convalescence, suggesting that SH2D1A protein is not directly responsible for control of EBV replication. Thus, genetic analysis of the SH2D1A gene is particularly useful in the diagnosis of sporadic cases and carriers of XLP. (Blood. 2001;98:1268-1270)

Adolescent↗
PubMed2001

Cardioprotective effect afforded by transient exposure to phosphodiesterase III inhibitors: the role of protein kinase A and p38 mitogen-activated protein kinase.

BACKGROUND: Phosphodiesterase III inhibitors (PDEIII-Is) improve the hemodynamic status of heart failure via inotropic/vasodilatory effects attributable to the increase in intracellular cAMP level. Direct cardioprotection by PDEIII-Is and its underlying mechanisms, however, have not been identified. We tested the infarct size-limiting effect of PDEIII-Is and the roles of cAMP, protein kinase (PK) A, PKC, and mitogen-activated protein kinase (MAPK) families in open-chest dogs. Methods and Results-- Milrinone, olprinone (PDEIII-Is), or dibutyryl-cAMP (db-cAMP) was injected intravenously 30 minutes before 90-minute ischemia, followed by 6 hours of reperfusion. Olprinone was also examined with an intracoronary cotreatment with a PKA inhibitor (H89), a PKC inhibitor (GF109203X), an extracellular signal-regulated kinase kinase (MEK) inhibitor (PD98059), or a p38 MAPK inhibitor (SB203580) throughout the preischemic period. Either PDEIII-Is or db-cAMP caused substantial hemodynamic changes, which returned to control levels in 30 minutes. Collateral flow and percent risk area were identical for all groups. Both PDEIII-Is and db-cAMP increased myocardial p38 MAPK activity during the preischemic period, which was blocked by H89, but not by GF109203X. Both PDEIII-Is and db-cAMP reduced infarct size (19.1+/-4.1%, 17.5+/-3.3%, and 20.3+/-4.8%, respectively, versus 36.1+/-6.2% control, P<0.05 each). Furthermore, the effect of olprinone was blunted by either H89 (35.5+/-6.4%) or SB203580 (32.6+/-5.9%), but not by GF109203X or PD98059. H89, GF109203X, PD98059, or SB203580 alone did not influence infarct size. CONCLUSIONS: Pretreatment with PDEIII-Is has cardioprotective effects via cAMP-, PKA-, and p38 MAPK-dependent but PKC-independent mechanisms in canine hearts.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2001

Long-term hormonal regulation of the cAMP-specific phosphodiesterases in cultured FRTL-5 thyroid cells.

Thyrotropin (TSH) and pharmacological agents that elevate intracellular cAMP concentrations potentiate the mitogenic response of FRTL-5 thyroid cells to insulin-like growth factor-I (IGF-I). This study was undertaken to determine the role of cAMP phosphodiesterases (PDEs) in this TSH-dependent regulation. Incubation of FRTL-5 cells with TSH, forskolin, or dibutyryl cAMP gradually induced the PDE activity, and treatment for 24 h produced a marked increase in type 4 high affinity cAMP PDEs. Under basal conditions, transcripts corresponding to PDE4A, PDE4B, PDE4C, and PDE4D were present. Stimulation for 24 h by TSH, forskolin or dibutyryl cAMP induced an increase in mRNA levels of PDE4B, PDE4D, and PDE4C. To understand the role of this cAMP-dependent PDE regulation in the potentiation of the mitogenic response to IGF-I, thymidine incorporation into DNA in response to IGF-I and TSH was measured in the absence or presence of PDE inhibitors. Exposure of the cells to 3-isobutyl-1-methylxanthine (IBMX) or RO 20-1724 had opposing effects on thymidine incorporation into DNA, depending on the stimulus applied. When IGF-I was used alone, both IBMX and RO 20-1724 potentiated IGF-I-stimulated thymidine incorporation. However, when IGF-I and TSH at high concentrations were used in combination, these PDE inhibitors blocked thymidine incorporation into DNA. In addition, these inhibitors depressed the synergistic increase in cyclin D1 and cyclin D- or cyclin E-associated cyclin-dependent kinase (CDK) activity that is induced by TSH and IGF-I. Increased CDK activities have been shown to play a crucial role in progression through the G(1)/S phase of the cell cycle. These data demonstrate that TSH produces marked changes in the cAMP degradative pathway of FRTL-5 cells by regulating the expression of cAMP PDEs. The regulation of the intracellular cAMP levels by this mechanism may contribute to the TSH- and IGF-I-dependent control of the entry into the S phase of the cell cycle through changes in the cyclin/CDK system in FRTL-5 cells.

1-Methyl-3-isobutylxanthine↗
PubMed2001

Computer-assisted complete three-dimensional reconstruction of the mammary ductal/lobular systems: implications of ductal anastomoses for breast-conserving surgery.

BACKGROUND: The intraductal spread of breast carcinoma can occur along the mammary ductal/lobular systems (MDLS) with no invasion of tissues. Because ductal anastomoses in the MDLS are considered to be a possible risk factor for extensive intraductal spread of breast carcinoma, the architecture of the MDLS has important therapeutic implications for patients treated with breast-conserving surgery. METHODS: An entire breast resected by subcutaneous mastectomy from a 69-year-old woman with ductal carcinoma in situ (DCIS) was examined in submacroscopic sections by stereomicroscopic and histologic techniques. Serial 2-mm sections underwent computer-assisted complete three-dimensional reconstruction of all MDLS. RESULTS: The entire breast that was studied contained 16 MDLS that were arranged radially, with the nipple at the center. Of these 16 MDLS, 4 (25.0%) had ductal anastomoses whereas the remaining 12 MDLS had no ductal anastomoses and completely independent regional anatomy. Ductal anastomoses were observed at 11 sites in the 4 MDLS. The 2 of 11 ductal anastomoses that connected different MDLS (18.2%) were situated > 4 cm from the nipple. The remaining nine ductal anastomoses connected ducts within the same MDLS; their location varied from near the nipple to the peripheral region. In the specimen examined, DCIS extended only within a single MDLS and did not spread between different MDLS via ductal anastomoses. CONCLUSIONS: To the authors' knowledge, the current study is the first time the complete architecture of all MDLS in an entire breast has been studied three-dimensionally. The risk of promoting the intraductal spread of disease during surgery may be greater when intraductal lesions extend more peripherally than centrally. The features of ductal anastomoses may provide a significant anatomic clue regarding negative surgical margins in breast-conserving surgery.

Aged↗