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T Isobe

Publications and source records attributed to T Isobe.

At least 37 records · Page 2Linked to original sources
PubMed2001

Association between expression of the MRP3 gene and exposure to platinum drugs in lung cancer.

To investigate the roles played by the multidrug resistance-associated protein (MRP1) homologues MRP3 and MRP4 in resistance to platinum drugs, we examined steady-state levels of mRNA for both MRP3 and MRP4 in normal lung and lung cancer specimens as well as peripheral mononuclear cells (PMN) after platinum drug exposure. MRP3 and MRP4 gene expression levels were monitored in the PMN of 10 previously untreated lung cancer patients within 24 hr after carboplatin (CBDCA) administration. Expression levels for both genes were also examined in 80 autopsy samples (40 primary tumors and 40 corresponding normal lung tissues) from 40 patients with lung cancer. MRP3 and MRP4 gene expression levels were assessed by quantitative reverse transcription-polymerase chain reaction. MRP3 expression levels in the PMN rose rapidly within 24 hr after administration of CBDCA, whereas MRP4 expression levels remained the same. Furthermore, MRP3 expression levels in normal lung and tumor tissues from autopsy samples that had been exposed to platinum drugs while the patients were alive were significantly higher than those in unexposed tissues, but again MRP4 expression levels remained the same. These results suggest that platinum drugs and/or the physiological stress response to xenobiotics induce expression of the MRP3 gene.

ATP-Binding Cassette Transporters↗
PubMed2001

Distribution and behavior of nonylphenol, octylphenol, and nonylphenol monoethoxylate in Tokyo metropolitan area: their association with aquatic particles and sedimentary distributions.

Distributions of alkylphenols (APs) [i.e., nonylphenol (NP), octylphenol (OP)], and nonylphenol monoethoxylate (NP1EO) in wastewater effluents, river water, and riverine and bay sediments in the Tokyo metropolitan area were demonstrated. During sewage treatments, NP and OP were efficiently removed from the sewage effluents through activated sludge treatments. Greater removal for NP (93% on average) than OP (84% on average) was consistent with their partitioning behavior to particles in primary and secondary effluents. NP concentrations in the river water samples ranged from 0.051 to 1.08 microg/L with higher concentrations in summer and spring than in colder seasons. In the river water samples, approximately 20% of NP was found in the particulate phase. Organic carbon-normalized apparent partition coefficients (K'OC) for NP (10(5.22 +/- 0.38)) and OP (10(4.65 +/- 0.42)) were 1 order of magnitude higher than those expected from their octanol-water partition coefficients (K(OW)), indicating strong affinity of APs to aquatic particles. Among NP isomers, no significant differences in their K'OC values were suggested. This is consistent with surprisingly uniform isomer peak profiles among the technical standard and all the environmental samples analyzed. NP and OP were widely distributed in the river sediments in Tokyo, and relatively high concentrations (0.5-13.0 microg/g dry) of NP were observed in a long reach (approximately 10 km) in the Sumidagawa River. In situ production of APs in the river sediment was suggested. Seaward decreasing trend in APs concentration was observed from the estuary to the Tokyo Bay. APs were well preserved in a sediment core collected from the bay. The profile shows subsurface maximum of AP concentrations in the layer deposited around the mid-1970s. The recent decrease in AP concentrations can be attributed to the legal regulation of industrial wastewater in the early 1970s.

Cities↗
PubMed2001

Plastic resin pellets as a transport medium for toxic chemicals in the marine environment.

Plastic resin pellets (small granules 0.1-0.5 centimeters in diameter) are widely distributed in the ocean all over the world. They are an industrial raw material for the plastic industry and are unintentionally released to the environment both during manufacturing and transport. They are sometimes ingested by seabirds and other marine organisms, and their adverse effects on organisms are a concern. In the present study, PCBs, DDE, and nonylphenols (NP) were detected in polypropylene (PP) resin pellets collected from four Japanese coasts. Concentrations of PCBs (4-117 ng/g), DDE (0.16-3.1 ng/g), and NP (0.13-16 microg/g) varied among the sampling sites. These concentrations were comparable to those for suspended particles and bottom sediments collected from the same area as the pellets. Field adsorption experiments using PP virgin pellets demonstrated significant and steady increase in PCBs and DDE concentrations throughout the six-day experiment, indicating that the source of PCBs and DDE is ambient seawater and that adsorption to pellet surfaces is the mechanism of enrichment. The major source of NP in the marine PP resin pellets was thought to be plastic additives and/or their degradation products. Comparison of PCBs and DDE concentrations in mari

Adsorption↗
PubMed2001

NMR structure of Streptomyces killer toxin-like protein, SKLP: further evidence for the wide distribution of single-domain betagamma-crystallin superfamily proteins.

A protein isolated from the culture supernatant of the soil bacterium, Streptomyces sp. F-287, exhibits cytocidal effects for both budding and fission yeasts, and causes morphological changes of yeasts and filamentous fungi. This protein, which was the first killer toxin-like protein for yeasts identified in the Streptomyces microorganism, was named SKLP (Streptomyces killer toxin-like protein). Since the amino acid sequence of the protein, as determined by sequential Edman degradations, seemed to be unique, we determined the structure by NMR spectroscopy. Although the actual target of SKLP in yeasts has not been determined yet, the structure might give us a clue to characterize the targets. The solution structure of SKLP determined by NMR, however, turned out to be a single-domain crystallin-like protein, with two Greek key motifs and a short extra beta-strand at the N terminus. The final ensemble of 20 NMR structures overlaid onto their mean coordinate with rmsd values of 0.32(+/-0.06) A for the backbone atoms involved in the secondary structure elements. As a yeast killer toxin, WmKT, isolated from the yeast strain Williopsis mrakii also has a Greek key beta-barrel fold, we have made a detailed comparison of the structural features of SKLP with the other crystallin superfamily proteins. It is very interesting that SKLP has a unique electrostatic potential distribution on the molecular surface. Namely, one surface of the beta-barrel fold in SKLP has a large negatively charged region, with an isolated positive charge of the Arg62 side-chain at the center. The edge of this surface is surrounded by positively charged residues, including Arg31, Arg65 and Arg74. The salient features of the charge distribution on this surface and the cluster of Arg residues might be related to the target binding of SKLP.

Amino Acid Motifs↗
PubMed2001

Isolation and proteomic characterization of the major proteins of the nucleolin-binding ribonucleoprotein complexes.

Nucleolin (NCL) is one of the most abundant nucleolar proteins of exponentially growing eukaryotic cells. It is known to interact only transiently with rRNA and preribosomal particles and not to be detectable in mature cytoplasmic ribosomes, and is believed to function as multi-protein complexes during ribosome biogenesis and maturation. However, those multiprotein complexes remain only partially characterized due to the difficulty of conventional protein analysis methods. Here we report isolation of NCL-binding protein complex and its proteomic characterization with the use of an analytical method based on matrix-assisted laser desorption/ionization-time of flight analysis coupled with searching peptide mass databases. The NCL-binding protein complex was isolated by immunoprecipitation with anti-Flag antibody from human kidney 293 cells that were transfected with the Flag-tagged NCL gene, and showed RNA integrity for holding their protein constituents. Interaction between NCL and its binding complex was disrupted by an RNA oligonucleotide with a NCL recognition element, indicating that NCL binds to the ribonucleoprotein (RNP) complex mainly through the sequence specific protein-RNA interaction. We confirmed that an RNA-binding domain of NCL alone was sufficient to hold the entire NCL-binding RNP complex, indicating the strict binding specificity of NCL to the isolated RNP complex in 293 cells. We identified forty ribosomal proteins from both the large and small subunits, and twenty nonribosomal proteins. These results together suggest that the isolated NCL-binding RNP complex is a preribosomal particle present in the nucleolus of 293 cells.

Blotting, Western↗
PubMed2001

Induction of cytochrome P450 3A4 by docetaxel in peripheral mononuclear cells and its expression in lung cancer.

Several recent studies have demonstrated that the cytochrome p450 (CYP) family plays an important role in the metabolism of taxanes. However, the role of CYP gene expression in tumors and peripheral mononuclear cells (PMN) is unknown. We therefore investigated the levels of CYP3A4 and CYP2C gene expression using reverse transcription polymerase chain reaction (RT-PCR) in PMN from 16 previously untreated lung cancer patients to determine whether the expression of the two genes is induced by docetaxel (TXT). Neither the CYP3A4 nor the CYP2C gene was induced after administration of carboplatin (CBDCA) alone. Expression of the CYP3A4 gene was induced by the administration of TXT alone or TXT and CBDCA, but expression of the CYP2C gene was unaffected. We also measured the expression of both genes using RT-PCR in 20 autopsy samples (ten non-small-cell lung cancers and their corresponding normal lung tissues) obtained from patients who had not received any chemotherapy during life. The level of CYP2C gene expression in samples of lung cancer was significantly higher than in normal lung tissue, but the level of CYP3A4 gene expression was not. These results suggest that the CYP3A4 gene is induced by TXT, and that it plays an important role in intracellular TXT metabolism.

Aged↗
PubMed2001

BIA-MS-MS: biomolecular interaction analysis for functional proteomics.

One of the experimental processes of functional proteomics is the analysis of protein interaction. Here, we review a new analytical platform, BIA-MS, for protein interaction analysis. BIA-MS is an integration of a surface plasmon resonance biosensor for real-time interaction analysis and mass spectrometry for the subsequent identification of interacting molecules.

Biosensing Techniques↗
PubMed2001

Kinetic analysis of cytokine gene expression in patients with GVHD after donor lymphocyte infusion.

Patients who receive a donor lymphocyte infusion (DLI) for the treatment of relapsed leukemia after allogeneic BMT (alloBMT) often developed GVHD. To determine whether cytokines might have a role in GVHD, an intensive kinetic analysis of in vivo cytokine gene expression was performed on PBMC from three such patients. Expression of IL-1beta, IL-2, IFN-gamma, IL-4, IL-5, IL-8, IL-10, IL-12, TNF-alpha, and IL-2Ralpha was examined using a sensitive semi-quantitative reverse transcription (RT)-PCR assay system. Six normal controls were also analyzed for comparison. Expression of type 1 T helper (Th1) cytokines, IL-2 and IFN-gamma was greatly increased in all three patients. In particular, the changes in IL-2 gene expression correlated well with disease progression, suggesting that IL-2 has a critical role in the development of GVHD. Although the pattern of type 2 T helper (Th2) cytokine gene expression differed in each patient, the expression of IL-4 was inversely related to expression of Th1 cytokines. These results suggest that Th1 dominates in the development of human clinical GVHD.

Adult↗
PubMed2001

Molecular characterization of a peroxiredoxin from the hard tick Haemaphysalis longicornis.

Antioxidant enzymes in eukaryotes play an important role in protection against the oxygen radicals generated during aerobic metabolism. Here we report the cloning and characterization of a cDNA encoding the antioxidant enzyme peroxiredoxin from the hard tick Haemaphysalis longicornis (HlPrx). HlPrx is 939 bp long and contains a 101 bp non-translated sequence at the 5' end and a polyadenylation singnal followed by a poly(A) tail at the 3' end. HlPrx encodes a full-length protein with a predicted molecular mass of 26 kDa that possesses one cysteine residue at amino acid 49 that is conserved among Prx proteins of various species. GenBanktrade mark analysis showed that the deduced amino acid sequence had significant similarity to mammalian and plant Prxs at the amino acid level. A DNA-nicking assay revealed that Escherichia coli-expressed recombinant HlPrx (rHlPrx) inhibited oxidative-nicking of supercoiled plasmid DNA. Two-dimensional immunoblot analysis with mouse antirHlPrx serum showed reaction with a major constituent protein spot in extracts of adult ticks. In addition, immunoblot analysis showed that rHlPrx was immunoreacted with serum from rabbits repeatedly infested with H. longicornis. Localization analysis using mouse antirHlPrx serum revealed that native HlPrx was highly expressed in the salivary gland of the tick. Moreover, Northern blot analysis showed that the level of HlPrx transcripts was increased during blood sucking. The present results indicate that HlPrx may be an important detoxifying enzyme during the normal life span as well as during blood sucking in ticks.

Amino Acid Sequence↗
PubMed2001

Right internal jugular vein venography in infants and children.

UNLABELLED: We obtained venograms of the right internal jugular vein (RIJV) in 105 infants and children with congenital heart disease during cardiac catheterization. No major anomalies were found in the course of the RIJV. The diameter of the RIJV tended to increase with the patient's age, weight, and height. However, some disproportionately small vessels were seen in 8% of the patients. The depth from the skin to the RIJV varied from 2.5 to 20 mm and did not significantly correlate with age, weight, or height. Confirmation of the diameter or the depth of the RIJV by venography may facilitate clinical decisions and may be useful for performing percutaneous cannulation. IMPLICATIONS: We obtained venograms of the right internal jugular vein in children with congenital heart disease. Generally, the diameter increased with the patient's body size, but disproportionately small vessels were seen in 8% of the patients. Preoperative internal jugular venography may facilitate identifying those patients.

Catheterization, Peripheral↗
PubMed2001

SGLT gene expression in primary lung cancers and their metastatic lesions.

Cancer cells show increased glucose uptake and utilization in comparison with their normal counterparts. Glucose transporters play an important role in glucose uptake. We previously reported the differential gene expression of the GLUT family in primary and metastatic lesions of lung cancer. To investigate the role of Na( +) / glucose cotransporter (SGLT) genes in cancers, we examined the levels of expression of SGLT1 and SGLT2 genes in primary lung cancers and their metastatic lesions. Ninety-six autopsy samples (35 primary lung cancers, 35 corresponding normal lung tissues, 10 metastatic liver lesions, and 16 metastatic lymph nodes) from 35 patients were analyzed for SGLT1 and SGLT2 expression by reverse transcription (RT)-polymerase chain reaction (PCR). There were no significant differences in the level of expression of either gene between the primary lung cancers and normal lung tissues. The level of SGLT1 expression in the metastatic lesions and primary lung cancers did not differ significantly. The level of SGLT2 expression was, however, significantly higher in the metastatic lesions of both the liver and lymph node than in the primary lung cancers. These results suggest that SGLT2 plays a role in glucose uptake in the metastatic lesions of lung cancer.

Adult↗
PubMed2001

Intranasal immunization with recombinant Ascaris suum 14-kilodalton antigen coupled with cholera toxin B subunit induces protective immunity to A. suum infection in mice.

Animals can be rendered immune to Ascaris parasites by immunization with infectious-stage larvae. The specific parasite gene products that mediate protective responses in ascariasis are unknown. We have identified a cDNA encoding Ascaris suum 14-kDa antigen (As14) and evaluated the vaccinal effect of the Escherichia coli-expressed recombinant protein (rAs14). GenBank analysis showed that As14 has low similarity at the amino acid level to a Caenorhabditis elegans gene product and to antigens of the filarial nematodes but not to other known proteins. In addition, As14 homologues were found to be expressed in human and dog roundworms. In mice that received intranasal administration of rAs14 coupled with cholera toxin B subunit (rAs14-CTB), there was a 64% reduction of recovery of larvae compared with that in the nontreated group. The vaccinated mice showed a significant increase in the total serum immunoglobulin G (IgG) levels and the mucosal IgA responses. Elevation of the rAs14-specific IgE response was also seen. Measurement of the IgG subclasses showed a higher level of IgG1 and a lower level of IgG2a antibody response in the sera of the immunized mice, suggesting that protection was associated with a type II immune response. As14 is the first protective antigen against A. suum infection to be identified. Our immunization trial results in laboratory animals suggest the possibility of developing a mucosal vaccine for parasitic diseases caused by ascarid nematodes.

Administration, Intranasal↗
PubMed2001

Relation between brain displacement and local cerebral blood flow in patients with chronic subdural haematoma.

OBJECTIVES: To evaluate the relation between brain displacement, clinical signs and symptoms, and local cerebral blood flow (lCBF) in patients with chronic subdural haematoma (CSDH). METHODS: Forty five patients (age range 58-87 years, mean 71.9 (SD 8.4)) with unilateral CSDH were studied. Patients were categorised into three groups: I, headache (n=16); II, paresis (n=14); and III, mental change (n=15). T1 weighted MR images were obtained in all patients preoperatively. Quantitative values of maximum haematoma thickness, midline shift, and brain rotation angle were measured on axial and coronal MR images. In 21 patients, lCBF was measured by Xe enhanced CT. Values for lCBF were obtained in selected regions of interest in the frontal cortex, thalamus, and hemisphere on both the haematoma and contralateral sides. RESULTS: The lCBF reduction in the ipsilateral frontal cortex showed the best linear correlation with haematoma thickness (r=0.57), whereas the reduction in the ipsilateral thalamus had the most significant correlation with pineal shift (r=0.65) and third ventricle incline (r=0.67). In patients with paresis, lCBF decreased significantly on the ipsilateral side of both the frontal cortex and thalamus (p<0.05), whereas patients with mental change showed a significant reduction of lCBF on both sides of the thalamus (p<0.01) and in the ipsilateral frontal cortex (p<0.01). CONCLUSIONS: The lCBF reduction and clinical symptoms correlated well with local brain displacement in patients with CSDH. The lCBF in the central cerebral area including the thalamus was reduced in patients with clinical signs. The mental changes found were thought to derive from mild impairment of consciousness due to upper brain stem displacement.

Aged↗
PubMed2001

Cloning and chromosome mapping of human and chicken Iroquois (IRX) genes.

Three highly homologous homeobox genes (caupolican, araucan and mirror) have been identified in Drosophila. These genes belong to the novel Iroquois complex, which acts as a pre-pattern molecule in Drosophila neurogenesis. Recently several vertebrate Iroquois homologues (Irx) were isolated and found to be involved in pattern formation of various tissues. Here we report cytogenetic mapping of four human and five chicken Iroquois genes by FISH. Our findings revealed that vertebrate Irx genes are clustered at two different loci.

Amino Acid Sequence↗
PubMed2001

Identification of larval-stage antigens of ascaris suum recognized with immune sera from pigs.

Antigens were identified from the third-stage larvae (L3) and lung-stage larvae of Ascaris suum by two-dimensional immunoblot method with antisera obtained from pigs that received chemically abbreviated Ascaris suum larval infections. Forty-seven and 13 spots were recognized as antigens from the L3 and lung-stage larvae, respectively. Their apparent molecular weight ranged from 20 to 101 kDa and their isoelectric point from 3.6 to 8.0. The present study provides a framework for further molecular cloning of those antigens and consequently leads to the development of recombinant peptide vaccines against A. suum.

Animals↗