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T Awata

Publications and source records attributed to T Awata.

At least 73 records · Page 4Linked to original sources
PubMed1992

Characterization of swine short interspersed repetitive sequences.

Swine genomic DNA segments containing repetitive sequences were isolated from a porcine genomic library using genomic DNA as a probe. Three fragments containing the repetitive sequences from two of the primary phage clones were subcloned for sequence analysis, which revealed six new PRE-1 repetitive families other than those reported earlier by Singer et al. (Nucleic Acids Research 15, 2780, 1987). The frequency of the repetitive sequences in the swine genome was estimated at 2 x 10(6) per diploid genome. Sequence analysis revealed similarities between these repetitive sequences and that of arginine-tRNA gene.

Animals↗
PubMed1991

Additive effect of islet amyloid polypeptide (IAPP/amylin) and insulin on 2-deoxyglucose uptake in mouse pancreatic acini.

The effect of islet amyloid polypeptide (IAPP/amylin) on 2-deoxyglucose (2-DG) uptake was studied in isolated mouse pancreatic acini in the absence or presence of insulin. Synthetic rat IAPP-NH2 caused a dose-dependent stimulation of 2-DG uptake by mouse acini with a half-maximal concentration at 70 nM. The increase in 2-DG uptake by 1 microM IAPP-NH2 or 100 nM insulin was 68% or 60% above basal, respectively. In the presence of both 1 microM IAPP-NH2 and 100 nM insulin, the increase in 2-DG uptake was 145% above basal, indicating that the effects of IAPP-NH2 and insulin on 2-DG uptake were additive. The results suggest that IAPP stimulates glucose uptake in mouse acini probably by a different mechanism from that of insulin.

Amyloid↗
PubMed1991

Uneven-distribution of short interspersed repetitive sequence, PRE-1, on swine chromosomes.

We investigated the distribution of PRE-1 sequences (a swine major SINE) on the swine chromosomes. The investigation demonstrated that PRE-1 sequences are unevenly distributed along the chromosomes as in the case of the human and mouse SINES. The distribution pattern, however, has no simple correlation with Q-band pattern as that of human and mouse SINES. The prominent difference is as follows; PRE-1 is localized on centromeric regions, but human and mouse SINES are not [KORENBERG and RYKOWSKI (1988). Cell, 53: 391-400; BOYLE, BALLARD, and WARD (1990). Proc. Natl. Acad. Sci. U.S.A. 87: 7751-7761].

Animals↗
PubMed1991

Effect of new oral antidiabetic agent CS-045 on glucose tolerance and insulin secretion in patients with NIDDM.

OBJECTIVE: To study the effects of CS-045, a newly developed thiazolidine analogue, on glucose tolerance and insulin response to oral glucose load in patients with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS: Nineteen NIDDM patients (mean +/- SD age 48.9 +/- 9.4 yr) whose previous glycemic control on diet and/or sulfonylurea (SU) therapy was judged stable but unsatisfactory (greater than 7.8 mM) were selected for this study. CS-045 (400 mg/day p.o.) was given alone or together with the previous SU drugs for 12 wk. A 75-g oral glucose tolerance test (OGTT) was performed before and after CS-045 treatment. RESULTS: The following results were found after CS-045 treatment. 1) Fasting plasma glucose (FPG) and HbA1c decreased (n = 19, FPG, 11.0 +/- 2.4 vs. 8.4 +/- 2.7 mM [before vs. after], P less than 0.001; HbA1c, 8.0 +/- 1.1 vs. 7.4 +/- 1.3%, P less than 0.005), and glucose tolerance markedly improved. 2) Fasting insulin (immunoreactive insulin [IRI]) and insulin response during OGTT decreased (n = 19, fasting IRI, 77.4 +/- 49.8 vs. 56.5 +/- 24.6 pM [before vs. after], P less than 0.05; area under the curve of IRI, 540.3 +/- 350.5 vs. 426.4 +/- 216.3 pM.h, P less than 0.05). CONCLUSIONS: CS-045 is effective in improving glucose tolerance without stimulation of insulin secretion in NIDDM, suggesting an effect in improving insulin sensitivity.

Blood Glucose↗
PubMed1990

Hypervariable region 5'-flanking [Leu A3]insulin gene of insulin Tochigi is different from those of insulin Wakayama I,II.

Three families with abnormal insulinemia have been reported in Japan and sequencing analysis revealed that they had the same point mutation in one allele of the insulin genes causing [Leu A3]insulin. To estimate whether or not this same mutation came from a common ancestor we determined the sequence of the hypervariable region 5'-flanking the third [Leu A3]insulin allele (insulin Tochigi). This region is composed of 42 tandem repeating oligonucleotides, is 599 base pairs long and the sequence is 5' cdi jfa faa aba baa aaa fab aaa caa aac aca cba aaf ccb 3' (abbreviated as a = ACAGGGGTGTGGGG; b = ACAGGGGTCTGGGG; c = ACAGGGGTCCTGGGG; d = ACAGGGGTCCGGGG; f = ACAGGGGTCCCGGGG; i = ACAGGGTCCTGGGG; j = ACAGGGGTGTGAGG). The length of this region is different from those of the first and second [Leu A3]insulin alleles (insulin Wakayama I,II). This difference suggests either that insulin Tochigi and insulin Wakayama I,II are not of the same origin, or that three cases of [Leu A3]insulin in Japan have the same ancestor but recombination has occurred in this region at some point in the past.

Base Sequence↗
PubMed1990

High frequency of aspartic acid at position 57 of HLA-DQ beta-chain in Japanese IDDM patients and nondiabetic subjects.

The HLA-DQ beta-chain (DQB1) genes of 72 Japanese patients with insulin-dependent diabetes mellitus (IDDM) and 85 control subjects were studied with polymerase chain-reaction (PCR) amplification and allele-specific oligonucleotide hybridization. DQW4 (DQBBlank) and DQw9 (DQB3.3) were increased in IDDM patients compared with the control subjects, and DQB1.2, DQB1.9, and DQw7 (DQB3.1) were decreased. Thirty-five (48.6%) IDDM patients had both alleles carrying an aspartic acid at position 57 of the DQ beta-chain (Asp 57), 35 (48.6%) were Asp 57/non-Asp 57 heterozygous, and 2 (2.8%) had non-Asp 57 alleles only. Of 85 control subjects, the respective values for these three genotypes were 49 (57.6%), 29 (34.1%), and 7 (8.2%), respectively. The high frequency of Asp 57 alleles in both IDDM and control subjects contrasts with data for Whites. Therefore, the Asp 57 hypothesis that the presence of an aspartic acid at position 57 of DQ beta-chain provides protection against developing IDDM is not tenable for Japanese IDDM patients. The DRB1 gene, particularly position 57 of the DR beta-chain, may contribute to IDDM susceptibility in Japanese.

Adolescent↗
PubMed1989

The effect of long-term topical administration of commercial beta-blockers on the rat corneal endothelium.

To determine the effect of long-term topical application of commercial beta-blockers on the corneal endothelium, normal rats were randomly assigned to receive a drop of 0.5% timolol, 1% befunolol, or 2% carteolol four times daily for 8 months. Specular microscopy showed marked pleomorphism in the endothelium after three months of treatment with 1% befunolol. In contrast, the eyes treated with either 0.5% timolol or 2% carteolol demonstrated no significant change in endothelial morphology. Scanning and transmission electron microscopy at eight months after treatment revealed marked degeneration of the endothelium of the eyes treated with 1% befunolol. Similar endothelial changes were also noted in the 0.5% timolol-treated group, but to a significantly lesser extent. The eyes treated with 2% carteolol, however, showed only mild alteration of the endothelial ultrastructure. These results indicate that the corneal endothelium can be affected by long-term topical administration of commercial beta-blockers.

Administration, Topical↗
PubMed1989

Intraocular penetration of CT-112, an aldose reductase inhibitor, following topical instillation.

Intraocular penetration of 5-(3-ethoxy-4-pentyloxyphenyl)thiazolidine-2,4-dione (CT-112), an aldose reductase inhibitor, was investigated in rabbits following topical instillation. The concentration of CT-112 in corneal epithelium, stroma, endothelium, lens, and aqueous humor, was sequentially determined by high-performance liquid chromatography. CT-112 peaked in the corneal epithelium, stroma, endothelium and aqueous humor in 30 minutes following instillation, then gradually diminished time-dependently over a period of 24 hours. CT-112 remained detectable in the lens up to 24 hours, with a peak concentration at 2 hours after instillation.

Administration, Topical↗
PubMed1989

A 595 nanometer band-pass filter enhances the contrast of in situ hybridization signals on chromosome observed after biotin/avidin-alkaline phosphatase localization.

In situ hybridization with DNA probes labeled with biotin and detected by the avidin-alkaline phosphatase/5-bromo-chloroindoxyl phosphate-nitro blue tetrazolium system has been used to localize DNA sequences in chromosomes. To observe the hybridization signals, a phase contrast microscope has often been used because of the good visibility it provides. Use of a 595 nm band pass filter with the phase contrast microscope enhances signal contrast after in situ hybridization without reducing resolution.

Alkaline Phosphatase↗
PubMed1989

Differential regulation of fibronectin synthesis in three different types of corneal cells.

The production of fibronectin (FN) and its response to serum or epidermal growth factor (EGF) were investigated in three different types of rabbit corneal cells cultured in vitro. The corneal epithelial cells, stromal fibroblasts (keratocytes) and endothelial cells were separately cultured in different media: basic medium containing minimal serum (0.5%), basic medium with supplementary serum at a final concentration of 10% and basic medium with 100 ng/ml EGF, respectively. FN production by each type of cell was examined either by the immunofluorescent staining method or by the metabolic labeling method followed by immunoprecipitation of FN in the culture medium. Each type of corneal cell produced and secreted FN. FN secretion into the culture medium by keratocytes and by endothelial cells was enhanced by the addition of EGF. However, FN secretion by epithelial cells was lowered by the additional serum or EGF. Furthermore, when the epithelial cells were cultured in the basic medium, DNA synthesis was low but FN secretion was high. These results suggest that the control mechanism of FN production differs between epithelial cells and keratocytes or endothelial cells.

Animals↗
PubMed1988

HLA DR antigens in adult-onset and juvenile-onset Japanese insulin-dependent diabetic patients.

In order to discover the HLA DR antigens linked to Japanese insulin-dependent diabetes (IDDM), and to relate them to the clinical features, HLA DR antigens were examined in 75 IDDM patients including 56 adult-onset cases. Among the tested HLA DR antigens, 4, w9 and w13 were significantly more frequent in IDDM (55%, 47% and 27% respectively). The relative risk was 1.71 for DR4, 2.81 for DRw9 and 4.74 for DRw13. DR2 was significantly less frequent and the relative risk was 0.14. The distribution of DR antigens did not differ between juvenile-onset and adult-onset IDDM, males and females, or cases with and without thyroid autoantibodies. Homozygotes for DRw9 were, but those for DRw13 and DR4 were not more frequent than expected by a random combination. Heterozygotes for DR4 and w9 were less frequent while other heterozygotes for high-risk antigens were as frequent as expected. 97% of IDDM had either DR4, w9 or w13. In conclusion, HLA DR4, w9 and w13 were significantly increased in patients with both juvenile- and adult-onset IDDM. There was no surplus increase in the frequency of IDDM patients with two high-risk HLA DR antigens, more than expected from random combination of each of these DR antigens. Clinical features did not differ among IDDM patients with each of these three antigens.

Adult↗
PubMed1988

Enhancement of the sensitivity for in situ detection of alkaline phosphatase using a homopolymer of 2-acrylamide 2-methylpropanesulfonate.

In order to enhance the sensitivity of detection of alkaline phosphatase immobilized on nitrocellulose, a homopolymer of 2-acrylamide 2-methylpropanesulfonate (poly-AMPS) and agarose were added to the reaction mixture using 5-bromochloroindoxyl phosphate and nitroblue tetrazolium. By addition of the above ingredients, the amount of the reaction product deposited on the nitrocellulose filters on which alkaline phosphatase had been dot-blotted was increased, and darkening of the background (un-dot-blotted area) was prevented. Reflective densitometry revealed that the addition of poly-AMPS and agarose increased the sensitivity of the detection approximately three times higher than without the use of these compounds.

Acrylamides↗
PubMed1988

Effect of an aldose reductase inhibitor, CT-112, on healing of the corneal epithelium in galactose-fed rats.

The effect of an aldose reductase inhibitor, CT-112 (5-(3-ethoxy-4-pentyloxyphenyl)2,4-thiazolidinedione), ophthalmic solution on wound healing in the corneal epithelium of rats fed on 50% galactose diet was investigated in correlation with CT-112 concentration. Rats were divided into 6 groups and those in 5 groups were fed on 50% galactose diet and 10 microliter of 0.1, 0.25, 0.5 and 1% CT-112 ophthalmic solutions or of their vehicle were instilled into both eyes 4 times a day. The animals in the remaining one group were fed on the regular diet and no treatment was given. After 18 days, the whole corneal epithelium was scraped off and the rate of reepithelialization was investigated over a 4-day period. Reepithelialization was delayed in galactosemic rats, but the instillation of CT-112 ophthalmic solutions improved the wound healing, although no differences in efficacy was found at the concentrations used. Moreover, the appearances of the cornea at 4 days after epithelial scraping were improved dose-dependently by the instillation of CT-112.

Aldehyde Reductase↗
PubMed1988

Identification of nucleotide substitution in gene encoding [LeuA3]insulin in third Japanese family.

We previously described a new case of abnormal insulinemia in Japan. In one allele, nucleotide-sequence analysis revealed a substitution in the codon for the third position of insulin A chain (GTG----TTG), causing [LeuA3]insulin. This point mutation is the same as that found in insulin Wakayama. In this family, the mutant insulin allele cosegregated with an 850-base pair PvuII allele of the hypervariable region 5'-flanking the insulin gene.

Base Sequence↗
PubMed1987

The effects of aldose reductase inhibitor on the corneal endothelial morphology in diabetic rats.

Diabetic rats were produced by intravenous injection of streptozotocin. Of these, eleven rats were treated with topical instillation of 0.5% aldose reductase inhibitor (ARI), while ten received vehicle alone. The corneal endothelium of these diabetic rats was examined by specular microscopy and compared to age-matched nondiabetic rats (ten rats). Computerized morphometric analysis of individual cells demonstrated that the endothelium of the untreated diabetic rats had marked polymegathism (increased coefficient of variation in cell area) and pleomorphism (decreased percentage of hexagonal cells), as previously observed in diabetic patients. Similar endothelial changes were also noted in the ARI-treated diabetic rats, but to a significantly lesser extent. These results suggest that topically applied ARI can be effective in reducing morphologic changes of the diabetic endothelium, and that activation of the sorbitol pathway may be implicated in the etiology of such endothelial changes.

Aldehyde Reductase↗
PubMed1986

Effects of aldose reductase inhibitor, CT-112, on sugar alcohol accumulation in corneal epithelium of galactose-fed rats.

A study was made of inhibitory effects of an aldose reductase inhibitor, CT-112 (5-(3-ethoxy-4-pentyloxyphenyl)-2,4-thiazolidinedione) ophthalmic solution, on the accumulation of sugar alcohol (dulcitol) in the corneal epithelium of rats fed on a 50% galactose diet. The effects were correlated with the concentrations of the drug solution. The rats were divided into 6 groups. One group was fed on a regular laboratory chow and was untreated. The other 5 groups were fed on a 50% galactose diet, and 0.1, 0.25, 0.5 or 1.0% CT-112 ophthalmic solution or its vehicle was instilled in both eyes 4 times a day in each of the 5 treated groups. After 2 weeks, the corneal epithelium was scraped off in all rats and its dulcitol content was determined by gas chromatography. CT-112 ophthalmic solution was found to inhibit the accumulation of dulcitol in a dose-dependent manner, except for the 1.0% solution which had an activity comparable to the 0.25% solution.

Aldehyde Reductase↗