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Biomedical subjects

Y Tsuchiya

Publications and source records attributed to Y Tsuchiya.

At least 91 records · Page 5Linked to original sources
PubMed1997

High ratios of free to total insulin-like growth factor-I in early infancy.

Insulin-like growth factor-I (IGF-I) is a major effector of somatic growth and metabolism. In normal, nonpregnant plasma, most of the IGF-I is complexed to specific IGF-binding proteins (IGFBPs), particularly IGFBP-3; only a minor fraction of plasma IGF-I exists in a free form. Recently, we have reported that free IGF-I levels, as measured using a new immunoradiometric assay, are relatively high in maternal plasma during pregnancy because of increased IGFBP-3 proteolytic activity. These high free IGF-I levels are physiologically important for the growth of maternal tissues such as uterus and placenta, which are related to the fetal growth. Growth during early infancy may be a continuation of fetal growth. In the present study, we have analyzed free and total plasma IGF-I and IGFBP-3 proteolytic activity in early infancy. Although the levels of free and total IGF-I were not significantly different in early infancy as compared with prepubertal periods, the ratio of free to total IGF-I (mean = 2.04%) was relatively increased and was similar to the ratio in pregnancy plasma (1.86%). However, unlike in maternal plasma, the high ratios were not totally caused by increased IGFBP-3 proteolytic activity. Our results suggest that there may be an increased conversion of plasma IGF-I to a free form in early infancy. The resultant increase in IGF-I bioavailability could contribute to the rapid somatic growth in early infancy.

Adult↗
PubMed1997

Effect of a new hypoglycemic agent, A-4166 [(-)-N-(trans-4-isopropylcyclohexanecarbonyl)-D-phenylalanine], on postprandial blood glucose excursion: comparison with voglibose and glibenclamide.

(-)-N-(trans-4-Isopropylcyclohexanecarbonyl)-D-phenylalanine (A-4166) is a new nonsulfonylurea hypoglycemic agent that lowers blood glucose by stimulating insulin release. In the present study, we examined the effects of A-4166, voglibose (an alpha-glucosidase inhibitor), and glibenclamide (a sulfonylurea) on the postprandial glycemic increase in rats with or without diabetes mellitus. Oral administration of A-4166 (25-100 mg/kg) dose-dependently decreased blood glucose with a rapid onset and short duration in normal rats. On the other hand, glibenclamide (1-4 mg/kg) showed a slower onset of its hypoglycemic action, and voglibose (0.2 mg/kg) had no effect. In the case of postprandial glucose excursion, the carbohydrate-induced increase in blood glucose was reduced by oral administration of either A-4166 or voglibose without causing sustained hypoglycemia in both normal and neonatal streptozotocin-induced diabetic rats. However, the efficacy of voglibose varied with the type of carbohydrate load. Glibenclamide produced a prolonged decrease in blood glucose without any appreciable effect on the initial glucose excursion. After sucrose loading, plasma insulin levels during the initial 1 h were significantly higher in A-4166-treated rats than in control rats, while voglibose completely inhibited the insulin response to sucrose. In glibenclamide-treated rats, an augmented insulin response was not seen. In conclusion, unlike other hypoglycemic agents, A-4166 suppresses postprandial glucose excursions by stimulating the early phase of insulin secretion.

Animals↗
PubMed1997

Clinical efficacy of interferon therapy for chronic hepatitis C in the Kita-Kyushu District of Japan.

The Kita-Kyushu district in Japan is one of the areas known to have a quite high prevalence of HCV infection. We analyzed the results of interferon therapy administered to 50 chronic hepatitis C patients living in this area (33 males and 17 females; ages between 28 and 65 years old). Interferon-alpha (human lymphoblast interferon, HLBI), 6 million units/day, was administered for 24 consecutive weeks. Before the therapy, the HCV levels, HCV-RNA genotype, and sequence of hypervariable region (HVR) of HCV were examined. Patients who were HCV-RNA negative and ALT < or = 30 IU/L at the completion of therapy and in the 6th month after the completion of therapy, were determined as complete responders (CR). In this study, 10 of 50 patients (20%) were CR. Among male patients, there were no CR in each age group, whereas among female patients aged over 40 years old, there were no CR. The number of patients with low virus levels was larger in the genotype 2a/2b cases than in the genotype 1b cases. HVR sequences varied extensively, and had no correlation to interferon efficacy. Multivariate analysis showed that the pre-treatment HCV level is the most important predictor.

Adult↗
PubMed1997

[Type III procollagen N-terminal aminopeptide and type IV collagen 7S in pleural effusion fluid].

The mechanism of pleural fibrosis in malignant and inflammatory pleural effusion remains unclear. We measured the levels of type III procollagen N-terminal amino peptide (PIIIP) and type IV collagen 7S in patients who had pleural effusion and lung carcinoma, and in others who had inflammatory diseases (parapneumonic and tuberculous pleuritis). The PIIIP level and the PIIIP/type IV collagen 7S ratio in patients with malignant pleural effusion were significantly lower than those in patients with inflammatory pleural effusion (p < 0.01), but the levels of type IV collagen 7S did not differ. The ratio of PIIIP to type IV collagen 7S was higher in patients with tuberculous pleuritis than in those with parapneumonic pleuritis (p < 0.05). These data indicate that pleural fibrotic adhesion may be accelerated in inflammatory pleural effusion because of elevated production of type III collagen; basement membrane injury in malignant and inflammatory pleural effusion may be caused by similar damage. We conclude that a high level of PIIIP and a high PIIIP/type IV collagen 7S ratio may indicate the presence of inflammatory pleuritis, and that the latter may indicate the presence of tuberculous pleuritis.

Aged↗
PubMed1996

Analysis of a 36.2 kb DNA sequence including the right telomere of chromosome VI from Saccharomyces cerevisiae.

The nucleotide sequence of a 36.2-kb distal region containing the right telomere of chromosome VI was determined. Both strands of DNA cloned into cosmid clone 9965 and plasmid clone pEL174P2 were sequenced with an average redundancy of 7.9 per base pair, by both dye primer and dye terminator cycle sequencing methods. The G+C content of the sequence was found to be 37.9%. Eighteen open reading frames (ORFs) longer than 100 amino acids were detected. Four of these ORFs (9965orfR017, 9965orfF016, 9965orfR009 and 9965orfF003) were found to encode previously identified genes (YMR31, PRE4, NIN1 and HXK1, respectively). Six ORFs (9965orfR013, 9965orfF018, 9965orfF006, 9965orfR014, 9965orfF013 and 9965orfR020) were found to be homologous to hypothetical 121.4-kDa protein in the BCK 5' region, Bacillus subtilis DnaJ protein, hypothetical Trp-Asp repeats containing protein in DBP3-MRPL27, putative mitochondrial carrier YBR291C protein, Salmonella typhimurium nicotinate-nucleotide pyrophosphorylase, and Escherichia coli cystathionine beta-lyase, respectively. The putative proteins encoded by 9965orfF018, 9965orfR014 and 9965orfR020 were found to be, respectively, a new member of the family of DnaJ-like proteins, the mitochondrial carrier protein and cystathionine lyase.

Amino Acid Sequence↗
PubMed1996

Fifteen open reading frames in a 30.8 kb region of the right arm of chromosome VI from Saccharomyces cerevisiae.

The nucleotide sequence of cosmid clone 9765, which contains 30.8 kb of the right arm of chromosome VI, was determined. Both strands were sequenced, with an average redundancy of 8.17 per base pair by both dye primer and dye terminator cycle sequencing methods. The G+C content of the sequence was found to be 40.3%. Fifteen open reading frames (ORFs) greater than 100 amino acids and one tRNA-Tyr gene (SUP6) were detected. Seven of the ORFs were found to encode previously identified genes (HIS2, CDC14, MET10, SMC2, QCR6, PH04 and CDC26). One ORF, 9765orfF010, was found to encode a new member of the Snf2/Rad54 helicase family. Three ORFs (9765orfR002, 9765orfR011 and 9765orfR013) were found to be homologous with Schizosaccharomyces pombe polyadenylate binding protein, Escherichia coli hypothetical 38.1-kDa protein in the BCR 5' region, and transcription regulatory protein Swi3, respectively.

Adenosine Triphosphatases↗
PubMed1996

Clinical utility of insulin-like growth factor-I (IGF-I) and IGF binding protein-3 levels in the diagnosis of GH deficiency (GHD) during childhood.

Diagnosis of GH deficiency (GHD) has been done traditionally by the combination of auxological data and the results of GH provocation tests. Recently, limitations of GH provocation tests have been advocated. Thus, three extreme subgroups (G-1; normal, G2; severe GHD, G-3; short children with normal GH secretion) were selected in order to show that insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3) levels reflect GH secretion. In G-1 (n = 52), all had normal IGF parameters. In G-2 (n = 27), all had low IGF parameters. In G-3 (n = 28), all except for one patient had normal IGF parameters. Taken together with the assumption that GH secretion status is continuous from 0 to normal (or to acromegalic), the data on IGF parameters in the three subgroups indicate that they are functional tests for GH secretion. IGF-I and IGFBP-3, together with free IGF-I and acid-labile subunit, may replace GH provocation tests in the diagnosis of GH deficiency during childhood; these functional tests for GH secretion, which show minimal intradaily variation, are more physiological and cost-effective than GH provocation test.

Child↗
PubMed1996

Plasma free insulin-like growth factor I concentrations in growth hormone deficiency in children and adolescents.

Serum levels of total insulin-like growth factor I (IGF-I) correlate with growth hormone (GH) secretory status and are a useful parameter in the diagnostic evaluation of GH deficiency. Serum total IGF-I levels represent the combined quantity of free or unbound IGF-I and IGF-I that is bound to specific IGF binding proteins. Free IGF-I (fIGF-I), which is postulated to be the bioactive fraction, accounts for only a small fraction of the total amount. We have recently developed a new immunoradiometric assay (IRMA) for plasma fIGF-I and have investigated fIGF-I in relation to GH status. The simple, non-extraction assay procedure involves the capture of unbound IGF-I by anti-IGF-I antibody coated to polystyrene beads and detection by a radiolabelled anti-IGF-I antibody directed to a separate epitope. Preliminary studies demonstrated that the fIGF-I IRMA does not measure IGF-I that is complexed to IGF-binding proteins and that the equilibrium between the free and bound fractions is not disturbed during the assay. Free IGF-I levels were compared to total IGF-I levels measured in the same IRMA after acid-ethanol extraction of the samples. Normal levels of fIGF-I from infancy through adulthood were found to have a close correlation with total IGF-I levels, with the lowest levels occurring in infancy and peak levels during puberty. Patients with complete GH deficiency had low levels of both fIGF-I and total IGF-I, with 94% and 100% of the levels below the 5ht percentile for age, respectively. On the other hand, approximately 90% of patients with normal IGF binding protein-3 levels among partial GH deficiency and normal short children had free and total IGF-I levels above the 5th percentile for age. These data indicate that the clinical utility of plasma fIGF-I measurements is similar to measurements of total IGF-I in the evaluation of childhood GH deficiency.

Adolescent↗
PubMed1996

Does gallstone formation after open cardiac surgery result only from latent hemolysis by replaced valves?

OBJECTIVES: To clarify the relationship between open heart surgery and gallstone formation. METHODS: Fifty-one patients without gallstones (Group A) underwent cardiac surgery using a heart-lung machine and were followed for 24 months by ultrasonography. Blood tests of hemolysis markers were examined before, immediately after, and 3, 6, and 12 months after surgery. And 52 healthy candidates without gallstone (Group B) also were followed for 24 months. RESULTS: The cumulative gallstone incidence in Group A was 15.7% at 3 months after surgery, 23.9% at 6 months, and 30.4% at and beyond 12 months and was significantly higher than that of Group B (p < 0.01). The stones showed a high dense pattern, indicative of pigment stones, in eight of the 10 patients assessed by CT. With respect to the type of surgery, latent hemolysis was seen only in patients who underwent mechanical valve replacement. However, there were no significant differences in the gallstone incidence between the patients who underwent mechanical valve replacement and those who underwent another cardiac surgery. The values of hemoglobin, haptoglobin, and lactate dehydrogenase showed abnormal values immediately after surgery, regardless of mechanical valve replacement or another cardiac surgery. CONCLUSIONS: The use of a heart-lung machine, which produces hemolysis, appears to have a close relation to gallstone formation after open cardiac surgery.

Cardiac Surgical Procedures↗
PubMed1995

Stochastic behavior of organelle motion in Nitella internodal cells.

The stochastic behavior of organelles during the recovery process of protoplasmic streaming is investigated in Nitella internodal cells at a nanometer space resolution. The motions of organelles in the components parallel and perpendicular to the alignment of actin filaments in the cell are analysed from the traces of displacement of 860 organelles in 1/30s (= video rate). The analysis of those traces shows that the generation of motive forces to the organelle follows the Poisson process. Therefore, we have been able to estimate the step size corresponding to the single force generation as approximately 100 nm.

Actins↗
PubMed1995

The effect of high-energy shock wave therapy combined with cisplatin on mouse hepatoma.

It is well documented that high-energy shock waves (HESW) can produce antitumor effects in vivo and in vitro. Furthermore, because HESW can be focused on a limited area, this therapy is considered applicable to the treatment of localized cancer. In this study, we investigated the effects of HESW therapy combined with cisplatin (CDDP) on MH134 hepatoma in a mouse model. Tumor growth was inhibited by 1 mg/kg CDDP treatment in combination with 2,000 HESW administration, but not by 1 mg/kg CDDP treatment only. Moreover, the CDDP concentration in the tumor increased after HESW administration. The active oxygen induced by HESW was then investigated by the electron spin resonance system, and it was found that HESW generated hydroxy-radicals. As oxygen radicals have been reported to change cell membrane potential, it is supposed that active oxygen induced by HESW changes cell membrane permeability, and that CDDP is concentrated in the tumor. Therefore, the combined therapy with HESW and CDDP showed synergistic inhibitory effects on tumor growth.

Animals↗
PubMed1995

Repeated piezoelectric lithotripsy for gallstones with and without ursodeoxycholic acid dissolution: a multicenter study.

The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring < or = 30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments < 3 mm. Stones were disintegrated in 97% of all patients, and the fragments were < or = 2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P = 0.61). Of the patients with fragments < or = 2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.

Cholelithiasis↗
PubMed1995

Clinical information on serum IGFBP-3 levels and IGFBP-3 proteolytic activity in childhood.

In this review paper, three pieces of clinical information in childhood are presented: (1) IGFBP-3 may replace GH provocation tests in the diagnosis of GH deficiency (GHD); (2) IGFBP-3 levels are regulated by IGF-I levels in a short period, and (3) ratio of free IGF-I to total IGF-I is high in serum of early infancy, similarly to serum of pregnancy, only partially owing to the presence of IGFBP-3 proteolytic activity. Each paper will be published soon.

Adolescent↗
PubMed1995

Analysis of the nucleotide sequence of chromosome VI from Saccharomyces cerevisiae.

The complete nucleotide sequence of Saccharomyces cerevisiae chromosome VI (270 kb) has revealed that it contains 129 predicted or known genes (300 bp or longer). Thirty-seven (28%) of which have been identified previously. Among the 92 novel genes, 39 are highly homologous to previously identified genes. Local sequence motifs were compared to active ARS regions and inactive loci with perfect ARS core sequences to examine the relationship between these motifs and ARS activity. Additional ARS sequences were predominantly observed in 3' flanking sequences of active ARS loci.

Base Composition↗
PubMed1995

Molecular, cytogenetic, and hematologic effects of ethylene oxide on female hospital workers.

Women comprise the majority of workers exposed to ethylene oxide during sterilization of medical instruments and supplies. This article evaluates molecular, cytogenetic, and hematologic effects of ethylene oxide on 68 women workers employed in nine hospitals in the United States and one hospital in Mexico. Workers were classified by three exposure categories: none (0), low (> 0-32 ppm-hrs), and high (> 32 ppm-hrs). Hematologic effects were evaluated using complete blood count with differential, which has been questioned as a test for screening ethylene oxide-exposed workers. A statistically significant decrease in hematocrit (n = 0.02) and hemoglobin (P = 0.03) levels, an increase in lymphocyte percentages (P = 0.04), and a relative decrease in neutrophil percentages (P = 0.03) with exposure were observed in US workers. The absolute number of lymphocytes, however, showed no relationship with exposure. No statistically significant results were seen for Mexican workers, although hematocrit decreased with exposure. An exposure-response relationship for the percentage for lymphocytes (positive) and neutrophils (negative) in US subjects and for neutrophils (positive) in Mexican subjects was seen. No overall relation with exposure was observed for total number of white cells. Molecular and cytogenetic results are also reported for the 68 women, who constitute a subgroup from a previous report. US women workers showed a statistically significant exposure-response relationship for ethylene oxide and hemoglobin adducts (P = 0.0002) and sister chromatid exchanges (P = 0.001). For micronuclei, the difference (P = 0.02) between low and high exposure was statistically significant. In Mexican workers, an exposure-response relationship was observed (P = 0.002) for hemoglobin adducts but not for sister chromatid exchanges or micronuclei.

Adult↗