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M Furuta

Publications and source records attributed to M Furuta.

At least 73 records · Page 4Linked to original sources
PubMed1998

Molecular cloning of m3 muscarinic acetylcholine receptor in rat iris.

Muscarinic receptor subtypes that involved in cholinergic responses in rat iris were identified by reverse transcription-polymerase chain reaction (RT-PCR) analysis. mRNAs encoding m2, m3, and m4 subtypes were abundantly expressed in iris, whereas m1 and m5 subtypes were not detected. Selective amplification of the coding regions of m2, m3, and m4 subtypes in iris was carried out using specific primers based on the sequence of each subtype previously cloned from rat brain and heart by RT-PCR. The amino acid sequence for iris m2 was different from published heart and genomic m2 by nine and one residue(s), respectively. It was also found that the sequence for m2 that in brain, heart, and several smooth muscles determined in the present study is completely identical to that in iris but not to that reported previously in heart. The sequence for iris m4 was completely identical to that for m4 in brain. The sequence identity between m3 subtype in iris and that in brain is 99.3%, with four amino acid substitutions at the sites of the position 165 and 184 in the edge of second intracellular loop and the sites of the position 337 and 406 in the central of i3 loop. It was found that iris m3 is slightly but substantially different in amino acid sequence from that in brain of the rat.

Amino Acid Sequence↗
PubMed1998

Schedule-dependent synergism and antagonism between paclitaxel and methotrexate in human carcinoma cell lines.

Paclitaxel and methotrexate are active against a variety of solid tumors. Because of differences in their mechanisms of action and toxicity profiles, the combination of these two agents has clinical potential. Clinical studies of this combination are in progress. We studied the optimal schedule of paclitaxel and methotrexate in combination at various schedules in vitro using human lung cancer A549, breast cancer MCF7, ovarian cancer PA1, and colon cancer WiDr cells. Cells were simultaneously exposed to paclitaxel and methotrexate for 24 h and sequentially exposed to paclitaxel for 24 h followed by methotrexate for 24 h or vice versa. Cell growth inhibition after 5 days was determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effects of drug combinations at the concentration of drug that produced 80% cell growth inhibition (the IC80 level) were analyzed by the isobologram method. The simultaneous exposure to paclitaxel and methotrexate produced additive to antagonistic effects in the A549 and PA1 cells, and antagonistic effects in the MCF7 and WiDr cells. The sequential exposure to paclitaxel followed by methotrexate produced additive effects in all four cell lines. The reverse sequence produced synergistic effects in the A549, MCF7, and WiDr cells, and additive effects in the PA1 cells. These findings suggest that a sequential administration of methotrexate followed by paclitaxel may be the appropriate schedule for this combination. On the basis of the observed in vitro synergism, further in vivo and clinical studies are necessary to clarify the toxicity and proposed antitumor effects of this schedule.

Antineoplastic Agents, Phytogenic↗
PubMed1998

Changes in plasma and urinary norepinephrine following transdermal clonidine in spontaneously hypertensive rats.

To support a long-lasting antihypertensive effect of transdermal clonidine (CAS 4205-90-7), changes in plasma norepinephrine (NE) levels and urinary NE excretion as indices of the sympathetic nervous activities were investigated following transdermal and oral clonidine in conscious spontaneously hypertensive rats. Plasma NE levels were significantly reduced for 24 h during transdermal application of clonidine patch at 1.5 and 4.5 mg/kg on the back of each rat. Oral clonidine at 100 microgram/kg also lowered plasma NE levels. However, significant falls in the levels lasted only for 4 h after oral dosing. Urinary NE excretion was significantly decreased during both 4-8 and 8-24 h periods, and during an 8-24 h period following transdermal clonidine at 1.5 and 4.5 mg/kg, respectively. Significant decrease in urinary NE excretion was also produced during a 4-8 h period following oral clonidine at 100 micrograms/kg. Total urinary NE excretion during a 0-24 h period was dose-dependently reduced following transdermal clonidine, but was not altered following oral dosing. These findings suggest that the sympathoinhibitory effect of transdermal clonidine is more persistent than that of oral clonidine. Therefore, long-lasting antihypertensive effect of transdermal clonidine is closely associated with the sustained suppression of the sympathetic nervous activity.

Administration, Cutaneous↗
PubMed1998

Ecological study of mean birth weight and nutritional intake in Japan.

The purpose of the present study was to assess the influence of nutrition on the nationwide decreases and regional differences in mean birth weight (MBW) recently observed in Japan. The relationship between MBW and nutritional intake was examined using nationwide data covering a two-decade time span from 1969 to 1988. The results of different statistical analyses indicate the MBW decreased uniformly in all 12 major regions of Japan over those 20 years (p < 0.0001). This trend was accompanied by decreases in energy and carbohydrate intake and increases in the intake of fat. We also found that the relationship between MBW and the nutrients is not linear but quadratic, showing declines in MBW only beginning from certain critical points. Hence we conclude that changes in MBW in Japan reflect the nutritional status of the Japanese, namely, decreases in the intake of energy and carbohydrate and an increase in fat intake in recent years. We also conclude that regional differences in MBW are concordant with differences in nutritional intake.

Birth Weight↗
PubMed1997

Outcome of radiation therapy for patients with Kasabach-Merritt syndrome.

PURPOSE: The efficacy of radiation therapy for Kasabach-Merritt syndrome, which is characterized by a huge hemangioma with consumption coagulopathy, remains controversial. In this study, we retrospectively investigated the treatment outcome of radiation therapy for seven neonates with Kasabach-Merritt syndrome. METHODS AND MATERIALS: During the past 25 years we have seen seven children with Kasabach-Merritt syndrome who were treated with radiation therapy. Their ages ranged from 1 day to 5 months, with a median age of 1 month. The hemangioma was located in the extremities in four of seven children. Tumor sizes ranged from 70 cm to more than 150 cm in greatest diameter. Initial platelet counts were all less than 40,000/mm3 except for one patient. In principle, the total dose applied to the hemangioma was 8-10 Gy, with a daily dose of 1 Gy five times a week. RESULTS: Four of seven hemangiomas responded dramatically, with a concomitant rise of the platelet count to radiation therapy. Although the remaining three hemangiomas, all of which were ill circumscribed by widespread overlying shiny, dusky purple skin, became less tense during radiation therapy. Disseminated intravascular coagulopathy was not improved, but they have responded favorably to two or three courses of radiation therapy with an extended radiation field by 1.5 years of age. As a result, all seven patients are now surviving with no evidence of hemangioma or hematological abnormalities. Shortening of the extremity was observed in three patients who received multiple courses of radiation therapy. CONCLUSIONS: Radiation therapy appears to be one of the effective treatment options for Kasabach-Merritt syndrome despite the risk of growth delay and malignancy.

Disseminated Intravascular Coagulation↗
PubMed1997

Defective prohormone processing and altered pancreatic islet morphology in mice lacking active SPC2.

The prohormone convertase SPC2 (PC2) participates in the processing of proinsulin, proglucagon, and a variety of other neuroendocrine precursors, acting either alone or in conjunction with the structurally related dense-core granule convertase SPC3 (PC3/PC1). We have generated a strain of mice lacking active SPC2 by introducing the neomycin resistance gene (Neor) into the third exon of the mSPC2 gene. This gene insertion results in the synthesis of an exon 3-deleted form of SPC2 that does not undergo autoactivation and is not secreted. The homozygous mutant mice appear to be normal at birth. However, they exhibit a small decrease in rate of growth. They also have chronic fasting hypoglycemia and a reduced rise in blood glucose levels during an intraperitoneal glucose tolerance test, which is consistent with a deficiency of circulating glucagon. The processing of proglucagon, prosomatostatin, and proinsulin in the alpha, delta, and beta cells, respectively, of the pancreatic islets is severely impaired. The islets in mutant mice at 3 months of age show marked hyperplasia of alpha and delta cells and a relative diminution of beta cells. SPC2-defective mice offer many possibilities for further delineating neuroendocrine precursor processing mechanisms and for exploring more fully the physiological roles of many neuropeptides and peptide hormones.

Animals↗
PubMed1997

The absence of synergism between the effects of an aldose reductase inhibitor, epalrestat, and a vasodilator, cilostazol, on the nerve conduction slowing and the myelinated fiber atrophy in streptozotocin-induced diabetic rats.

The preventive effects of combined or separate treatment for 10 weeks with an aldose reductase inhibitor, epalrestat (50 mg/kg/day), and a vasodilator, cilostazol (30 mg/kg/day), on nerve conduction deficits and morphometric alterations were examined in streptozotocin-induced diabetic rats. The average motor nerve conduction velocities (MNCV) in the tail nerve of the untreated diabetic (DM) group, the group treated with epalrestat (ES), the group treated with cilostazol (CZ), the group with both agents together (ES&CZ), and the normal control group were 34.7, 37.7, 39.3, 39.0 and 42.1 m/s, respectively. All treatments partially but significantly prevented a reduction in MNCV. The MNCV in the ES&CZ group was almost the same as in the CZ group. In a morphometric study of the sural nerve, the DM group showed a reduction in the average diameter of myelinated fiber and in occupancy (percentage of the fascicular area occupied by myelinated fibers), and a shift in the diameter-frequency histogram to smaller diameters. Only the CZ group showed evidence of a partial but significant preventive effect on the decrease in occupancy. In the CS and ES&CZ groups, there was a significant tendency away from the shift of histograms to smaller diameters. The ES&CZ group did not show any fewer morphometric changes than the CZ group. Thus, there was no synergism between the effects of epalrestat and cilostazol on the development of experimental diabetic neuropathy. This finding may provide a useful clue to the mechanisms of action of ES and CZ in diabetic neuropathy.

Aldehyde Reductase↗
PubMed1997

Rapid rise in FDG uptake in an irradiated human tumour xenograft.

In order to investigate early changes in the glucose metabolism of irradiated tumours, tumour uptake of 2-[18F]fluoro-2-deoxy-d-glucose (18FDG) was studied in human tumour xenografts. Three human tumour lines [ependymoblastoma (NNE), small cell lung cancer (GLS), and glioblastoma (KYG)] showing different radiosensitivities and incidences of radiation-induced apoptosis were subcutaneously transplanted into nude mice, and were irradiated at a single dose of 10 Gy. Then 0.5 mCi of 18FDG was intravenously administered 1 h before sacrifice. The animals were sacrificed at 2, 4 and 6 h following irradiation, and 18FDG accumulation in the tumours was examined. Before irradiation, GLS and KYG tumours showed significantly higher rates of 18FDG accumulation compared with NNE tumours (P <0.004 and P <0.001, respectively). NNE (the most radiosensitive tumour with the highest incidence of radiation-induced apoptosis), however, displayed a 2.3-fold higher rate of 18FDG accumulation at 2 h following irradiation compared with a non-irradiated group (P <0.01), and thereafter showed a plateau up to 6 h. The accumulation did not increase significantly in the other tumours with lower radiosensitivity and much less radiation-induced apoptosis. The rapidity of the increase in 18FDG accumulation in the most radiosensitive tumour line, occurring as early as 2 h following irradiation, suggests that the increase was independent of recovery phenomena following radiation damage.

Animals↗
PubMed1997

Radiation therapy for stage III non-small cell lung cancer invading chest wall.

The treatment outcome and prognostic factors for Stage III non-small cell lung cancer (NSCLC) invading the chest wall and treated with definitive radiation therapy alone were investigated. From 1976 to 1990, 40 consecutive patients with Stage III NSCLC invading the chest wall underwent radiation therapy alone. There were 31 with Stage IIIA and nine with Stage IIIB. Squamous cell carcinoma was present in 30 patients (75%). All the patients underwent radiation therapy at a total dose of 60-80 Gy at 2 Gy per fraction. Local pain completely disappeared in 11/13 (85%) and decreased in the remainder after treatment. The 5-year survival rate was 8% for all patients, 10% for Stage IIIA and 0% for IIIB (P = 0.02), 11% for lesions invading the parietal pleura and 0% for those invading the ribs or spine (P = 0.2). Good performance status, Stage IIIA, metastases of lymph nodes less than N3 and small tumor size were better prognostic factors by univariate analysis. By multivariate analysis, performance status (P = 0.01) and Stage (P = 0.03) were the important prognostic factors. Five-year local progression-free survival rates were 51% for patients with lesions invading the parietal pleura and 0% for those invading the ribs or spine (P = 0.009). Good pain relief was achieved in patients with lesions invading the ribs or spine by radiation therapy. Tumors invading the parietal pleura were fairly well controlled by radiation therapy alone.

Bone Neoplasms↗
PubMed1997

A simple improvement in expression cloning.

Expression cloning is an effective approach for isolating genes encoding proteins that associate with a target species. Several molecules have been isolated by expression cloning, including CRE-BP1 associating with Jun (Macgregor et al., 1990); Grb1, identical to p85 PI3-kinase, with the EGF receptor (Skolnik et al., 1991); and Max with Myc (Blackwood and Eisenman, 1991). Expression cloning involves induction of proteins from a lambda gt11 cDNA expression library and screening the proteins on nitrocellulose membranes using a peptide probe (Macgregor et al., 1990). With this method, we previously isolated an Lck tyrosine kinase-associated protein, LckBP1, which is identical to HS1 (Kitamura et al., 1989, 1995; Takemoto et al., 1995). In those experiments, we used a glutathione S-transferase (GST)-Lck SH3 domain fusion protein as a probe, followed by detection of the complex with anti-GST polyclonal antibody. Whereas the ease of obtaining the fusion construct and high-titer anti-GST polyclonal antibody represented clear advantages, the system suffered from high background and low sensitivity. Here we show that pretreatment of nitrocellulose filters with NaDodSO4 reduces background and, in turn, increases sensitivity.

Adaptor Proteins, Signal Transducing↗
PubMed1997

Expression plasmid vectors with convenient subcloning sites in lambda gt11 that efficiently produce detectable tagged proteins.

We have generated cDNA expression vectors that efficiently produce tagged proteins. The newly introduced cloning site of this plasmid facilitates subcloning of cDNA in the lambda gt11 phage into the plasmid vector. Because the cDNA is inserted next to the motifs of the tagged DNA sequence, the protein produced by the tag sequence-coupled cDNA is easily detected by Western blot analysis or immunoprecipitation using commercially available antibodies. The double-tagged protein significantly enhances the efficiency of Western blot and immunoprecipitation detection as compared with the single-tagged protein.

3T3 Cells↗
PubMed1997

Chlorella virus PBCV-1 encodes a homolog of the bacteriophage T4 UV damage repair gene denV.

The bacteriophage T4 denV gene encodes a well-characterized DNA repair enzyme involved in pyrimidine photodimer excision. We have discovered the first homologs of the denV gene in chlorella viruses, which are common in fresh water. This gene functions in vivo and also when cloned in Escherichia coli. Photodamaged virus DNA can also be photoreactivated by the host chlorella. Since the chlorella viruses are continually exposed to solar radiation in their native environments, two separate DNA repair systems, one that functions in the dark and one that functions in the light, significantly enhance their survival.

Amino Acid Sequence↗
PubMed1997

Comparison of postural control of children with Down syndrome and those with other forms of mental retardation.

To confirm the 1994 findings of Okuzumi, Haishi, and Kokubun, the displacement of the center of foot pressure, one-foot balance and head sway were measured in children with Down syndrome (n = 11) compared to those with other types of mental retardation (n = 17). The magnitudes of the displacement of the center of foot pressure and head sway were not significantly different between the Down group and other forms of mental retardation, whereas the performance of one-foot balance was significantly lower in the Down group. The mean frequencies of sway waves were generally higher in the Down group, and the differences between the two groups were significant except for sagittal head sway. The results generally supported the prior findings. We proposed that it was not the magnitude of the displacement of the center of foot pressure but rather the manner of the whole body's sway which might be related to postural control.

Adolescent↗
PubMed1997

Effect of Krestin as adjuvant treatment following radical radiotherapy in non-small cell lung cancer patients.

To evaluate the efficacy of Krestin (PSK) as adjuvant treatment after radical radiation therapy (RT) for non-small cell lung cancer (NSCLC), treatment results of 225 patients with NSCLC treated with RT followed by adjuvant administration of PSK between 1976 and 1989 were analyzed. Of these patients, 170 (76%) had squamous cell carcinoma. In the patients with squamous cell carcinoma of the lung, PSK was given only when the tumor showed satisfactory shrinkage (complete or partial response) after completion of RT. The treatment outcomes were compared with those of the responders to RT not receiving PSK. The 5-year survival rates of patients with stages I-II and stage III disease were 39 and 26%, respectively, while the non-administered responder group's were 17 and 8%. These differences are statistically significant. An improvement in the treatment results with combined use of appropriate immuno-modulating drugs is anticipated in the future. When clinical trials of the efficacy of these drugs are conducted, the agents should be given to the patients with satisfactory tumor regression after RT, although they still take much time and cost.

Adjuvants, Immunologic↗
PubMed1996

Analysis of 76 kb of the chlorella virus PBCV-1 330-kb genome: map positions 182 to 258.

Analysis of 76 kb of newly sequenced DNA, located between map positions 182 and 258 kb in the 330-kb chlorella virus PBCV-1 genome, revealed 175 open reading frames (ORFs) of 65 codons or longer. One hundred and five of these 175 ORFs were considered major ORFs. Twenty-one of the 105 major ORFs resembled proteins in databases including ribonucleotide reductase small subunit, RNase III, thioredoxin, glutaredoxin, protein disulfide isomerase, deoxynucleoside kinase, frog virus 3 ATPase, Acetobacter cellulose synthase, a bacteriophage encoded endonuclease, and two C-5 cytosine DNA methyltransferases. One of the ORFs was the PBCV-1 major capsid protein. The 105 major ORFs were evenly distributed along the genome. One set of ORFs was separated by 543 nucleotides whereas 75 of the ORFs were separated by fewer than 100 nucleotides. Nineteen of the 175 ORFs resembled other PBCV-1 ORFs, suggesting that they represent either gene duplications or gene families.

Amino Acid Sequence↗
PubMed1996

A stable phage-display system using a phagemid vector: phage display of hen egg-white lysozyme (HEL), Escherichia coli alkaline, phosphatase, and anti-HEL monoclonal antibody, HyHEL10.

A stable expression system for displaying the pIII fusion protein on the surface of a filamentous phage was constructed. A phagemid pIII display vector, pLUCK, was constructed by inserting the gene encoding the pIII fusion protein in the opposite direction to that of the lac promoter of pTZ18U. Using this phage display system, two enzymes, hen egg-white lysozyme (HEL) and E. coli alkaline phosphatase, and the single-chain Fv fragment of anti-HEL monoclonal antibody HyHEL10, could be stably and functionally displayed. Northern and primer extension analyses showed that a small amount of the sense mRNA encoding pIII-fused HEL was transcribed from the minor phage promoter located in the region encoding the C-terminus of pIII. Repressed expression of the pIII fusion protein can lead to the display of a wide range of proteins on filamentous phages without the need for strict expression conditions.

Alkaline Phosphatase↗
PubMed1996

Heterogeneous expression of recombination activating genes and surface CD5 in CD3low CD4+ CD8+ thymocytes.

Clonal selection in the thymus occurs mostly in the CD4+ CD8+ (double positive; DP) stage. Within DP thymocytes, cells in the CD3low subset are believed to be involved in clonal selection, and this subset is generally considered as a homogeneous population. T-cell antigen-receptor (TCR) signals on DP thymocytes are known to (i) down-regulate recombination activating gene (RAG) expression; and (ii) up-regulate the expression of T-cell function-associated molecules, including the cell surface glycoprotein CD5. The present study examined the expression of RAG and CD5 molecules among the subpopulations of normal adult DP thymocytes. DP thymocytes were fractionated according to their cell surface expression levels of TCR-CD3 complex into CD3dim, CD3lo, CD3med, and CD3hi cells, since TCR expression is known to increase during thymocyte maturation. Down-regulation of RAG mRNA was located between the CD3low and CD3med DP populations. However, within the DP CD3low subpopulation, we found that CD5 varies from low to high expression levels. Upon fractionation of DP CD3low thymocytes into CD5low and CD5high subsets, we were able to detect down-regulation of RAG transcripts within the CD3low subpopulation. Thus, by the criteria of CD5 surface expression and RAG mRNA expression levels, DP CD3low thymocytes can be considered a heterogeneous thymocyte subpopulation.

Animals↗