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Y Asahi

Publications and source records attributed to Y Asahi.

At least 19 recordsLinked to original sources
PubMed2006

High-resolution physical mapping and construction of a porcine contig spanning the intramuscular fat content QTL.

We previously mapped a locus for porcine intramuscular fat content (IMF) by linkage analysis to a 17.1-cM chromosome interval on Sus scrofa chromosome 7 (SSC7) flanked by microsatellite markers SW1083 and SW581. In this study, we identified 34 microsatellite markers and 14 STSs from the 17.1-cM IMF quantitative trait loci (QTL) region corresponding to HSA14q and aligned those loci using the INRA-University of Minnesota porcine radiation hybrid (IMpRH) panel. We then constructed a 5.2-Mb porcine bacterial artificial chromosome (BAC) contig of this region that was aligned using the RH panel. Finally, the IMF QTL was fine-mapped to 12.6 cM between SJ169 and MM70 at the 0.1% chromosome-wise significance level by genotyping the previously studied F2 resource family with 17 additional microsatellites. We also demonstrated that the SJ169-MM70 interval spans approximately 3.0 Mb and contains at least 12 genes: GALC, GPR65, KCNK10, SPATA7, PTPN21, FLJ11806, EML5, TTC8, CHES1, CAP2P1, CHORDC2P and C14orf143.

Adipose Tissue↗
PubMed2001

Involvement of GABAergic systems in manifestation of pharmacological activity of desipramine.

We have conducted this study to elucidate the influence of GABAergic systems on manifestation of pharmacological activity of desipramine using both pharmacological and electrophysiological methods. Desipramine (20 mg/kg, i.p.) significantly blocked the adjuvant-induced thermal hyperalgesia, which was facilitated by treatment with the GABA(A) antagonist picrotoxin (2 mg/kg, i.p.) or the GABA(B) antagonist saclofen (2 mg/kg, i.p.). This analgesic effect of desipramine was antagonized by post-treatment with picrotoxin or saclofen. However, none of these compounds showed any effect in normal animals without adjuvant-induced inflammation. In a slice preparation of the hippocampus, treatment with GABA (10(-5)-5 x 10(-4) M), baclofen (10(-5)-10(-4) M) or muscimol (10(-5)-10(-4) M) inhibited the field potential evoked in pyramidal neurons by Schaffer collateral stimulation. The inhibitory effect of GABA was facilitated by concurrent application of desipramine, carbamazepine or diazepam at a concentration of 5 x 10(-5)-2 x 10(-4) M. The rank of order of facilitation is: desipramine > carbamazepine > diazepam. Desipramine also enhanced the inhibitory effect of baclofen and muscimol. These results suggest that desipramine causes GABAergic systems to activate still more, and this phenomenon appears to be involved in manifestation of the pharmacological activity of desipramine such as antinociception.

Animals↗
PubMed2000

Regulation of granulocyte colony-stimulating factor and parathyroid hormone-related protein production in lung carcinoma cell line OKa-C-1.

Previously we have established a clonal squamous cell carcinoma cell line OKa-C-1 derived from lung cancer of a patient with marked leukocytosis and hypercalcemia. OKa-C-1 cells simultaneously produce granulocyte colony-stimulating factor (G-CSF) and parathyroid hormone-related protein (PTHrP) at the single cell level and cause paraneoplastic syndromes in nude mice bearing the tumor. It is known that the production of G-CSF and PTHrP is individually regulated by inflammatory cytokines in various malignant cells. To investigate the common factors in the regulation of G-CSF and PTHrP production in OKa-C-1 cells, we examined the effects of some inflammatory agents [lipopolysaccharide (LPS), phorbol-12-myristate-13-acetate (PMA), tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) beta and IL-6] on G-CSF and PTHrP production, by means of enzyme-linked immunosorbent assay (ELISA), immunoradiometric assay (IRMA) and quantitative reverse transcription-polymerase chain reaction (RT-PCR). TNF-alpha or IL-1beta induced both G-CSF and PTHrP production in the conditioned medium. TNF-alpha synergized with IL-1beta to significantly increase G-CSF production. In addition, TNF-alpha and IL-1beta strongly induced G-CSF mRNA with peaks at 2 and 6 h respectively. Although PTHrP production was also strongly induced by TNF-a PTHrP mRNA expression was more strongly induced by PMA than by TNF-alpha. Thus, TNF-alpha and IL-1beta could be common factors that individually and synergistically regulate G-CSF and PTHrP production in OKa-C-1 cells. Moreover, G-CSF and PTHrP production could be not only transcriptionally, but also posttranscriptionally regulated by other factors.

Animals↗
PubMed1999

Diversity of substitutions within or adjacent to conserved amino acid motifs of penicillin-binding protein 2X in cephalosporin-resistant Streptococcus pneumoniae isolates.

The sequence of an approximately 1.1-kb DNA fragment of the pbp2x gene, which encodes the transpeptidase domain, was determined for 35 clinical isolates of Streptococcus pneumoniae for which the cefotaxime (CTX) MICs varied. Strains with substitutions within a conserved amino acid motif changing STMK to SAFK and a Leu-to-Val change just before the KSG motif were highly resistant to CTX (MIC, >==2 microgram/ml). Strains with substitutions adjacent to SSN or KSG motifs had low-level resistance. The amino acid substitutions were plotted on the three-dimensional crystallographic structure of the transpeptidase domain of PBP2X. Transformants containing pbp2x from strains with high-level CTX resistance increased the CTX MIC from 0. 016 microgram/ml to 0.5 to 1.0 microgram/ml.

Amino Acid Sequence↗
PubMed1999

Fluoromicroscopic detection of myc-tagged GLUT4 on the cell surface. Co-localization of the translocated GLUT4 with rearranged actin by insulin treatment in CHO cells and L6 myotubes.

We earlier developed a novel method to detect translocation of glucose transporter type 4 (GLUT 4) directly, quantitatively and simply using c-MYC epitope-tagged GLUT4 (GLUT4myc) Kanai F, Nishioka Y, Hayashi H, Kamohara S, Todaka M, Ebina Y: J Biol Chem 268: 14523-14526, 1993). We further developed the method to visualize GLUT4myc on the cell surface++ by fluorescence microscope using a highly sensitive immunochemical detection system in tissue culture cells stably expressing GLUT4myc. The translocation of GLUT4myc was observed on stimulation with insulin in 3T3-L1 adipocytes, CHO cells and L6 myotubes stably expressing GLUT4myc. Platelet-derived growth factor (PDGF), norepinephrine and bradykinin also triggered GLUT4 translocation in CHO-GLUT4myc cells stably expressing each receptor. To observe the distribution of GLUT4 and actin after insulin treatment, double staining for GLUT4myc and actin was performed. Translocated GLUT4myc on the cell surface was co-localized with rearranged actin in CHO cells and L6 myotubes. This result suggests that a correlation exists between GLUT4 translocation and actin rearrangement.

3T3 Cells↗
PubMed1998

Association of a thr-371 substitution in a conserved amino acid motif of penicillin-binding protein 1A with penicillin resistance of Streptococcus pneumoniae.

We determined the nucleotide sequence between 1,903 and 3,097 bp of pbp1a, which encodes the transpeptidase domain of PBP 1A, from clinical isolates of penicillin-resistant Streptococcus pneumoniae (PRSP) serotypes 19 (n = 8), 6 (n = 9), 23 (n = 6), and 14 (n = 2) and two penicillin-susceptible S. pneumoniae (PSSP) isolates. These serotyped PRSP strains were isolated predominantly in Japan from 1993 through 1997. The 25 resistant strains were classified into five groups on the basis of the extent of sequence differences. Strains in groups I (n = 5; serotype 6), II (n = 3; serotype 19), and III (n = 12; different serotypes) had sequences highly homologous to the sequence of pbp1a of PRSP strains from South Africa, Spain, and the United States. The group IV strain (n = 1; serotype 14) had unique deletions from or insertions in the sequences. The sequences of group V strains (n = 4; serotypes 6 and 23) had relatively few differences from the sequences of the PSSP strains. For strains (n = 18) for which the threonine at codon 371 (Thr-371) in a conserved STMK motif of PBP 1A was substituted with an alanine or a serine (in addition to having altered pbp2x and pbp2b genes), penicillin MICs were >/= 1.0 microgram/ml. The PBPs 1A of these strains showed decreased affinities for [3H]benzylpenicillin and slightly faster mobilities on sodium dodecyl sulfate-polyacrylamide gels. In contrast, for strains (n = 4) without a substitution at Thr-371 in PBP 1A but with mutations in both pbp2x and pbp2b, penicillin MICs were 0.125 to 0.25 microgram/ml, and the affinities of their PBPs 1A were similar to that of PSSP PBPs 1A. Furthermore, for the Thr-371-substituted strains (n = 3) with altered pbp2x genes but native pbp2b genes, penicillin MICs were 0.125 to 0.25 microgram/ml. These results suggest that amino acid substitution of Thr-371 contributes to the development of penicillin resistance in PRSP strains with altered pbp2x and pbp2b genes.

Amino Acid Sequence↗
PubMed1998

Binding position of tolbutamide to human serum albumin.

The interaction between drugs (tolbutamide (1), 1-butyl-3-(methylsulfonyl)urea (2)) and human serum albumin (3) was investigated by equilibrium dialysis and NMR spectroscopy. The binding of 1 and 2 to 3 was concluded to be hydrophobic and hydrophilic, respectively, on the basis of the dependence of the binding constants on temperature, ionic strength, and chain length of fatty acid added. In 1H-NMR spectra of 1, there were no significant shifts with change in concentration or addition of 3. The spin-lattice relaxation time (T1) and spin-spin relaxation rate (1/T2) of the respective protons of 1 were independent of concentration, but depended on the concentration of 3 added. The binding position was determined from the ratio of 1/T2 of 1 bound to 3 and free 1. 1 and 2 were found to bind to 3 through the tolyl group and sulfonylurea group, respectively. The binding property of 1 was considered to be governed by the competition between the hydrophobic effect of the tolyl group and the hydrophilic effect of the sulfonylurea group in the molecule.

Binding Sites↗
PubMed1997

Plasma membrane content of insulin-regulated glucose transporter in skeletal muscle of the male Otsuka Long-Evans Tokushima Fatty rat, a model of non-insulin-dependent diabetes mellitus.

The male Otsuka Long-Evans Tokushima Fatty (OLETF) rat shows insulin resistance in skeletal muscle and visceral obesity. To obtain information on the mechanism of the insulin resistance in the diabetic rats, we examined the content of insulin-regulated glucose transporter (GLUT4) in skeletal muscles. The results indicate that the total content of the transporter is significantly decreased (P < 0.05) in muscles of the diabetic rats. Plasma membrane content of the GLUT4 protein in muscles of the diabetic rats was increased in the basal state as compared to control rats. Hyperinsulinemic clamps increased GLUT4 levels in the plasma membrane of control rats but failed to do so in the diabetic rats. The distribution of GLUT4 in OLETF rat is reminiscent of the characteristics of human non-insulin-dependent diabetes mellitus.

Animals↗
PubMed1997

Epithelioid sarcoma producing granulocyte colony-stimulating factor.

An epithelioid sarcoma of the perineum of a 60-year-old man with widespread metastases produced leukocytosis, myeloid hyperplasia of the bone marrow, and splenomegaly. High titers of granulocyte colony-stimulating factor (G-CSF) were found in the patient's serum and primary culture medium of the tumor tissue. The tumor tissue extract contained m-RNA for G-CSF in large quantities, proving that the tumor was the source of this cytokine.

Granulocyte Colony-Stimulating Factor↗
PubMed1997

Glucose transporter levels in a male spontaneous non-insulin-dependent diabetes mellitus rat of the Otsuka Long-Evans Tokushima Fatty strain.

Otsuka Long-Evans Tokushima Fatty (OLETF) rats are a new strain of spontaneous non-insulin-dependent diabetes mellitus (NIDDM) models. To evaluate the role of glucose transporters (GLUT) in the development of diabetes in this model, we examined the action of insulin on the translocation of GLUT4 and GLUT1 in isolated adipocytes, and the GLUT4 protein levels in muscles. Long-Evans Tokushima Otsuka (LETO) rats were used as a control strain. In adipocytes, the GLUT4 protein levels in OLETF rats at 30 weeks of age (diabetic stage) were considerably lower than those in LETO rats at the same age. At a pre-diabetic stage (7 weeks), there were no significant differences in GLUT4 protein levels in adipocytes between LETO and OLETF rats. However, the degree of GLUT4 translocation in OLETF rats was lower than that in LETO rats at 7 weeks of age. There were no differences in GLUT1 levels in adipocytes between the two strains. In muscles, the decrease in GLUT4 protein was observed in OLETF rats at 30 weeks of age. Whether such a difference is under the influence of hyperglycemia was also examined using rats rendered diabetic by 70% pancreatectomy. OLETF rats aged 7 weeks were subjected to partial pancreatectomy (Px) and sham pancreatectomy (sham). At 4 weeks after surgery, GLUT4 protein levels in adipose tissues and skeletal muscles were determined. GLUT4 decrease was observed for both tissues of hyperglycemic Px rats compared with euglycemic sham. Moreover, we examined the direct effect of glucose on GLUT4 protein using primary cultured adipocytes of OLETF rats at 5 weeks of age. After 7-day culture with normal (5.6 mmol/l) or high (25 mmol/l) concentrations of glucose, the GLUT4 protein levels in adipocytes decreased at 25 mmol/l glucose compared with 5.6 mmol/l glucose. These findings suggest an early defect in the insulin resistance of OLETF rats probably reflects impaired GLUT4 translocation. The GLUT4 decrease, which occurs later in the process appears to be a consequence, rather than a cause of diabetes in OLETF rats.

Adipocytes↗
PubMed1997

PTHrP-mediated hypercalcaemia in a case of CML blast crisis.

We report a 52-year-old man with chronic myelogenous leukaemia (CML) who developed hypercalcaemia in blast crisis. There was a high serum level of parathyroid hormone-related protein (PTHrP). The leukaemia cells secreted PTHrP into culture medium when cultured in vitro and were shown to express PTHrP mRNA by reverse transcription-polymerase chain reaction. Transplantation of the leukaemia cells into nude mice resulted in the production of Ph1 chromosome-positive tumours which caused increased levels of calcium and PTHrP in the blood. These results indicated that the hypercalcaemic event in the patient was induced by PTHrP of CML cell origin.

Blast Crisis↗
PubMed1997

Improving effect of carteolol on bodyweight and carbohydrate and lipid metabolic responses in the OLETF rat.

1. Carteolol, a non-selective beta-blocker with intrinsic sympathomimetic activity, admixed in a pellet diet was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an animal model of spontaneous non-insulin-dependent diabetes mellitus with mild obesity. A high dose of carteolol (0.02%) suppressed bodyweight gain without affecting food and water consumption until the appearance of glycosuria. Carteolol tended to reduce the cumulative incidence of glycosuria at 26 weeks after the beginning of administration (55, 17 and 25% in control rats, and in rats fed a low (0.002%) and high dose of carteolol, respectively). 2. At the 26th week of administration, the high dose of carteolol decreased visceral fat weight, such as that of retroperitoneal and epididymal adipose tissue, whereas the liver and the kidney were not affected. 3. Although plasma glucose and triglyceride levels in non-fasted rats were elevated with age, carteolol tended to delay the increases in those parameters. Carteolol suppressed the increase in plasma glucose levels, which indicate the diabetic pattern, in a 25th week oral glucose tolerance test. 4. These findings indicate that carteolol induces improvements in bodyweight and carbohydrate and lipid metabolism in an obese condition. Consequently, carteolol may be useful for the treatment of hypertension with obesity in order to prevent cardiovascular events.

Adipose Tissue↗
PubMed1997

Impaired beta-cell function and deposition of fat droplets in the pancreas as a consequence of hypertriglyceridemia in OLETF rat, a model of spontaneous NIDDM.

Hypertriglyceridemia is known to be a feature of obesity-related NIDDM, but the patho-etiological significance of this association is obscure. The effects of triglycerides (TGs) on beta-cell function and morphological changes in pancreas were examined using in vivo and in vitro approaches in male OLETF rats at ages 6, 12, and 30 weeks, with their diabetes-resistant counterpart, LETO rats, as normal controls. The results showed that, in the fasting state, plasma TGs in OLETF rats were increased 2.5-fold at age 6 weeks, 3.3-fold at age 12 weeks, and 6.2-fold at age 30 weeks, compared with age-matched LETO rats. The TG content in islets from 12-week-old OLETF rats was significantly increased when compared with those from their age-matched counterparts, but this was not the case with the 6-week-old OLETF rats. Therefore, the islets from 6-week-old rats were cultured with either free fatty acids (FFAs; 1.0 mmol/l sodium oleate) or TG (5.0 mmol/l Intralipide) for 72 h. Several abnormalities in OLETF rats were evident, in contrast to the results from control LETO rats: 1) glucose-induced insulin secretion was more inhibited by either FFAs or TGs in the presence of 27.7 mmol/l glucose, a result associated, at least in part, with reduced glucokinase activity in the islets; 2) a marked elevation in TG content was found in the islets; and 3) the deposition of fat droplets in the enlarged islets, even in the beta-cells, was found by Oil Red O-insulin double staining at age 30 weeks. In conclusion, hypertriglyceridemia resulted in significant TG stores in the islets, which subsequently inhibited glucose-induced insulin secretion, at least in part, via reduced glucokinase activity in the islets. Fat droplets in islets, therefore, may play an important role in hastening the development of NIDDM in this rat model.

Animals↗
PubMed1996

Establishment of a clonal cell line producing granulocyte colony-stimulating factor and parathyroid hormone-related protein from a lung cancer patient with leukocytosis and hypercalcemia.

Squamous cell lung carcinoma cells obtained from a patient who presented with leukocytosis and hypercalcemia were transplanted into nude mice and a serially transplantable cell line, OKa-N-1, was established. The nude mice transplanted with OKa-N-1 cells displayed leukocytosis and hypercalcemia. Serum levels of granulocyte colony-stimulating factor (G-CSF) and parathyroid hormone-related protein (PTHrP) were both elevated in these mice. In vitro cultivation of this tumor cell line gave rise to a clonal cell line, OKa-C-1. Nude mice transplanted with the OKa-C-1 cell line also showed leukocytosis and hypercalcemia with high serum G-CSF and PTHrP levels. The culture supernatant of OKa-C-1 contained high levels of G-CSF and PTHrP. Immunohistochemical studies showed the expression of PTHrP in OKa-C-1 cells. Reverse transcription polymerase chain reaction revealed the presence of G-CSF and PTHrP mRNA in this cell line. Dexamethasone treatment inhibited the transcription of G-CSF and PTHrP genes. This new human squamous carcinoma cell line, OKa-C-1, would be useful for studying the mechanism of simultaneous production of G-CSF and PTHrP and their control in cancer patients with leukocytosis and hypercalcemia.

Animals↗
PubMed1996

Lung squamous cell carcinoma producing both parathyroid hormone-related peptide and granulocyte colony stimulating factor.

An autopsy case of a 61 year old male with primary squamous cell carcinoma of the lung with associated marked leukocytosis and hypercalcemia is reported. High levels of serum parathyroid hormone-related peptide (PTHrP) and granulocyte colony stimulating factor (GCSF) were detected. The tumor cells distinctly showed positive cytoplasmic immunoreactions with anti-PTHrP and anti-GCSF antibodies. Marked granulocytosis and thin bony trabeculae lacking osteoblasts were observed in the vertebral bone. Calcium deposits were found in the proximal tubules of the kidneys. Infarcts were seen as a result of fibrin thrombosis of the splenic artery. The tumor was successfully transplanted into nude mice in which the high levels of serum PTHrP and GCSF were reproduced. These results indicate that the tumor simultaneously produced both PTHrP and GCSF causing the paraneoplastic syndromes of hypercalcemia and leukocytosis.

Animals↗
PubMed1996

Directly repeated insertion of 9-nucleotide sequence detected in penicillin-binding protein 2B gene of penicillin-resistant Streptococcus pneumoniae.

We investigated the molecular mechanism of 50 penicillin-resistant Streptococcus pneumoniae strains (penicillin: MIC, > or = 0.125 microgram/ml) having neither class A nor class B mutations in the penicillin-binding protein 2B gene (pbp2b). An analysis of the nucleotide sequences of the pbp2b genes from seven strains revealed an unique direct repeat of 9 nucleotides (TGGTATACT) between active-site serine (residue 385) and Ser-X-Asn (residues 442 to 444) motifs. The same insertion was detected in 13 strains.

Amino Acid Sequence↗