Biomedical subjects

T Adachi

Publications and source records attributed to T Adachi.

At least 307 records · Page 17Linked to original sources

PubMed1995

Regulation of IGF binding proteins by FSH in human luteinizing granulosa cells.

OBJECTIVE: To evaluate the regulation of the secretion of insulin-like growth factor (IGF) binding proteins (IGFBPs) by FSH in human luteinizing granulosa cells. DESIGN AND RESULTS: Luteinizing granulosa cells were incubated with and without FSH. Levels of IGFBP-1 and -3 in the medium were measured by EIA and RIA, respectively and binding activities of these IGFBP were evaluated by Western ligand blot. FSH inhibited the secretion of IGFBP-1 dose dependently. FSH did not inhibit the secretion of immunoreactive IGFBP-3, but inhibited the binding activity of IGFBP-3. To assess the protease activity, 125I-IGFBP-3 was incubated with the cultured medium. 125I-IGFBP-3 degraded into small fragments when it was incubated with the cultured medium treated with FSH. CONCLUSIONS: FSH enhances the action of IGF-I in human granulosa cells by inhibiting the secretion of IGFBP-1 and the binding activity of IGFBP-3 by stimulating the proteolysis of IGFBP-3.

Blotting, Western↗

PubMed1995

Interdigitated structure of phospholipid-alcohol systems studied by x-ray diffraction.

In the interdigitated structure of phosphatidylcholine/alcohol systems, the one-dimensional electron density profile in the direction normal to the membrane surface is generated from the x-ray diffraction pattern. The membrane thickness for these systems is expressed by the sum of the hydrocarbon chain lengths of phosphatidylcholine and alcohol molecules. For this study, various sets of phosphatidylcholines and 1-alcohols were used; a phosphatidylcholine has a carbon number from 14 to 18 in a hydrocarbon chain, and an alcohol has a carbon number from 1 (methanol) to 4 (1-butanol). Based upon the results, we propose a model for the interdigitated structure in which 1) two alcohol molecules occupy a volume whose surface is surrounded interstitially by the headgroups of phosphatidylcholine molecules, and 2) the methyl ends of both hydrocarbon chains in alcohol and phosphatidylcholine molecules face each other at the bottom of the volume.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1995

Calcium and magnesium absorption from the colon and rectum are increased in rats fed fructooligosaccharides.

We investigated the effects of fructooligosaccharides on the absorption of calcium, magnesium and water from the colon and rectum of rats fed a control diet or the control diet containing 50 g fructooligosaccharides/kg. Chromium-mordanted cellulose was used as an unabsorbable marker to calculate apparent absorption of calcium and magnesium. There was a positive correlation (r = 0.982, P < 0.001 in rats fed the control diet and r = 0.975, P < 0.001 in rats fed the fructooligosaccharides-containing diet) between the amount of chromium and the dry weight of each fecal pellet in the colon and rectum. Ratios of calcium to chromium and magnesium to chromium in fecal pellets in the colon and rectum were calibrated from the Ca:Cr and Mg:Cr ratios of cecal contents. In rats fed the fructooligosaccharides-containing diet, but not in rats fed the control diet, these ratios were correlated with the fractional length of transit along the colon and rectum, indicating linear disappearance of calcium and magnesium during the colorectal passage. Total apparent absorption of calcium and magnesium, predicted from regression equations with the Ca:Cr and Mg:Cr ratios of cecal contents, agreed well with those calculated from the Ca:Cr and Mg:Cr ratios of feces. The consumption of fructooligosaccharides did not affect net water absorption from the colon and rectum. These results indicated that fructooligosaccharides significantly increased calcium and magnesium absorption and that indigestible and fermentable carbohydrate facilitates colorectal absorption of calcium and magnesium.

Animals↗

PubMed1995

Heparin-induced release of extracellular-superoxide dismutase form (V) to plasma.

Extracellular-superoxide dismutase [EC 1.15.1.1] (EC-SOD) is a secretory, tetrameric glycoprotein. A prominent feature of EC-SOD is its affinity for heparin. This enzyme in serum is heterogeneous with regard to heparin-affinity and can be divided into five fractions (I) to (V) by heparin-HPLC, whereas fibroblast-secreted EC-SOD consists mainly of form (V). An intravenous injection of 50 i.u. of heparin/kg body weight into two healthy volunteers led to an immediate rise of serum EC-SOD level by 2.4-2.8-fold. Only form (V), which was a minor component in pre-heparin serum, was increased by the intravenous injection. The half-life of serum EC-SOD after the prompt rise was about 90 min. The in vivo experiment using rats and an in vitro experiment strongly suggested the EC-SOD released into the plasma reconstituted the interaction with glycocalyx on the vascular endothelial cell surface in accordance with the elimination of heparin from the vascular system.

Cell Line↗

PubMed1995

Chronic treatment with nitric oxide synthase (NOS) inhibitor profoundly reduces cerebellar NOS activity and cyclic guanosine monophosphate but does not modify minimum alveolar anesthetic concentration.

We previously found that acute administration of a nitric oxide synthase (NOS) inhibitor (N omega-nitro-L-arginine methyl ester [L-NAME]) does not reduce the minimum alveolar anesthetic concentration (MAC) of halothane in rats. However, a recent study has suggested that brain NOS activity could not be inhibited by more than approximately 50% by acute administration of L-NAME. To investigate the effect of marked inhibition of NOS activity on the MAC of halothane, we measured cerebellar NOS activity, cerebellar cyclic guanosine monophosphate (cGMP) levels, and halothane MAC in rats chronically treated with L-NAME and compared the results to those of the saline-treated control group. Although the cerebellar NOS activity and cGMP levels were significantly decreased (14% and 2.7% of control, respectively) by L-NAME, the value of the halothane MAC was not significantly affected. These results suggest that the anesthetic action of halothane, as measured by its MAC in rats, is not related to NOS activity or cGMP levels in the brain.

Animals↗

PubMed1995

A sporadic case of Ehlers-Danlos syndrome type IV: diagnosed by a morphometric study of collagen content.

A sporadic case of a young woman with Ehlers-Danlos syndrome (EDS) type IV is described. Multiple aneurysms of medium-sized arteries were noted. Histological study revealed deposition of acid mucopolysaccharides in the media of major arteries and in the intima of smaller arteries with intimal thickening. Systemic changes related to stenosis were observed in arteries more than 100 microns in diameter. Histologic study revealed hyperplasia of adipocytes in the submucosal layer of the intestines and the trachea, and fibrosis of Langerhans' islets of the pancreas. Typical signs for EDS such as skin hyperelasticity and joint hypermobility, and positive family history were not present. However, type III collagen was not detected on frozen sections from either the skin or the anterior cerebral artery by immunohistochemical quantification. Thus, it was concluded that the present case is a variant of EDS.

Adolescent↗

PubMed1995

Eosinophil viability-enhancing activity in sputum from patients with bronchial asthma, Contributions of interleukin-5 and granulocyte/macrophage colony-stimulating factor.

To investigate the mechanisms of eosinophil activation in the airways of patients with asthma, we attempted to detect eosinophil-activating cytokines in sputum extracts obtained from asthmatic patients during acute attacks or in remission by eosinophil survival assay. Purified guinea pig eosinophils were cultured in the presence or absence of sputum extracts, and the eosinophil viability was measured on Day 4. Eosinophil viability in the presence of sputum extracts derived from patients during moderate or severe attacks was significantly higher than that for sputum obtained from patients in remission or during mild attacks or from those with other respiratory diseases, including bronchiectasis and diffuse panbronchiolitis (p < 0.05). The total symptom score during the week prior to sputum collection correlated with the eosinophil viability (rs = 0.79, p < 0.01). Eosinophil viability-enhancing activity (EVEA) in the sputum of asthmatic patients with moderate or severe attacks was neutralized by anti-IL-5 antibody and by anti-GM-CSF antibody by 19.9 +/- 13.7% and 76.9 +/- 8.2% (mean +/- SEM, n = 7), respectively. EVEA was completely neutralized by a combination of anti-IL-5 and anti-GM-CSF antibodies. There was a significant correlation between the concentration of eosinophil cationic protein (ECP) in sputum extracts and the eosinophil viability (rs = 0.54, p < 0.05). These findings suggest that IL-5 and GM-CSF are present in the sputum during asthma attacks and that these cytokines are at least partially responsible for eosinophil activation in asthma.

Animals↗

PubMed1995

The heparin-binding site of human xanthine oxidase.

The enzyme xanthine oxidase (XOD) has an affinity for heparin and can bind to cultured porcine aortic endothelial cells. We have reported that the exposure of human XOD (h-XOD) to the lysine-specific reagent trinitrobenzenesulfonic acid or the arginine-specific reagent phenylglyoxal caused it to lose its affinity for heparin-Sepharose. The heparin-binding sites in h-XOD are further studied in the present article. From a chymotryptic digest of cyanogen bromide fragmented h-XOD, two peptides with an affinity for heparin-HPLC, A-1 and A-2, were isolated. Amino acid sequence analysis showed that both peptides had lysine and/or arginine residues. The A-1 region may direct its charged side chains toward the solvent while burying its hydrophobic side chains against the hydrophobic inside, because the A-1 peptide forms a highly amphipathic structure. Peptide A-2 contains triple lysine residues and constitutes a hydrophilic region.

Amino Acid Sequence↗

PubMed1995

Synthesis and opioid activities of [D-Leu-8]Dynorphin(1-8) analogs containing a reduced peptide bond, psi(CH2-NH).

[D-Leu8]Dynorphin(1--8)-NH2 analogs, in which each peptide bond was systematically replaced with a psi(CH2NH) peptide bond, were synthesized by the solid-phase method. The psi(CH2NH) bond was introduced by the Boc-amino acid aldehyde/NaCNBH3 method on a solid support. In the syntheses of the analogs, undesirable double alkylation took place at the sequences of Tyr1 psi(CH2NH)Gly2 and Gly2 psi(CH2NH)Gly3, possibly due to the low steric hindrance of the glycine residue. To suppress the double alkylation, a minimum amount of aldehydes was employed. In the receptor binding assay, the psi(CH2NH) replacement of N-terminal peptide bonds which led to 1 psi 2-(2) and 2 psi 3-analogs (3) resulted in a marked reduction in binding affinities for mu-, delta-, and kappa-opioid receptors, while that of the other peptide bonds afforded analogs with a high kappa-receptor affinity. A 3 psi 4-analogs (4) showed extremely high kappa-receptor selectivity (mu/kappa Ki ratio = 339, delta/kappa Ki ratio = 24104). In the in vitro bioactivity assay (guinea pig ileum assay), 2 showed a very low IC50 ratio (2.0) in the presence and absence of peptidase inhibitors whereas those of other analogs were >27, suggesting that the introduction of the CH2NH isostere at Tyr1-Gly2 greatly enhanced the enzymatic stability of the parent peptide. Furthermore, analogs 2 and 3 showed a very low sensitivity to the inhibitory effect of NaCl plus 5'-guanylylimidodiphosphate on their binding at a kappa-receptor site as compared with the other analogs and the parent peptide. These results suggest that the two analogs (2 and 3) have partial kappa-antagonist properties.

Amino Acid Sequence↗

PubMed1995

Four rice seed cDNA clones belonging to the alpha-amylase/trypsin inhibitor gene family encode potential rice allergens.

Four rice seed proteins encoded by cDNAs belonging to the alpha-amylase/trypsin inhibitor gene family were overexpressed as TrpE-fusion proteins in E. coli. The expressed rice proteins were detected by SDS-PAGE as major proteins in bacterial cell lysates. Western blot analyses showed that all the recombinant proteins were immunologically reactive to rabbit polyclonal antibodies and to a mouse monoclonal antibody (25B9) specific for a previously isolated rice allergen of 16 kDa. Some truncated proteins from deletion mutants of the cDNAs retained their reactivity to the specific antibodies. These results suggest that the cDNAs encode potential rice allergens and that some epitopes of the recombinant proteins are still immunoreactive when they are expressed as their fragments.

Allergens↗

PubMed1995

Isolation and culture of bovine mammary epithelial cells and establishment of gene transfection conditions in the cells.

Bovine mammary epithelial cells (BMEC) were isolated as acinous fragments from a mammary gland of a lactating cow. They grew well on plastic substratum, showed the characteristic cobblestone morphology of epithelial cells, and secreted alpha s1-, beta-, and kappa-caseins even when grown on plastic substratum. A plasmid containing the bacterial chloramphenicol acetyl transferase (CAT) gene was transfected to the isolated BMEC by calcium phosphate precipitation and electroporation methods. The transfection efficiency of BMEC by the calcium phosphate method was greatly improved by post-transfection osmotic shock with glycerol or polyethylene glycol. An about 700 bp DNA fragment containing 5'-flanking sequence of bovine alpha s1-casein gene showed promoter activity in the transfected BMEC. The primary culture of BMEC might be useful for studies on regulation of bovine milk-protein gene expression.

Animals↗

PubMed1995

Effects of adriamycin, an anticancer drug showing testicular toxicity, on fertility in male rats.

Adriamycin (ADR), an anticancer drug,was intravenously administered to Slc:SD male rats at doses of 0, 1 and 2 mg/kg once a week for 4 or 9 weeks before pairing, and the treatment period and parameters suitable for detection of male fertility disorder were examined. No adverse effects were observed on the copulation index, fertility index and spermatozoa, but testicular weights were low in the 1 and 2 mg/kg groups after 4-week treatment. In the 2 mg/kg group after 9-week treatment, 11 of 12 males had died or became moribund, and no successful pregnancies were observed. The males in the 1 and 2 mg/kg groups after 9-week treatment had decreased weights of the genital organs, an extremely decreased number of sperm and low sperm motility as well as a low implantation rate and a decreased number of live fetuses. Microscopically, the numbers of spermatogonia were decreased in the 1 and 2 mg/kg groups after 4-week treatment, whereas the numbers of even spermatozoa were diminished and genital organs showed atrophy after 9-week treatment. These results indicate that 4-week treatment before pairing is sufficient to detect effects of ADR on the testis, especially on spermatogonia, and that microscopic findings and testis weight are appropriate parameters for detection of male fertility disorders.

Animals↗

PubMed1995

Effects of fructooligosaccharides on the absorption of iron, calcium and magnesium in iron-deficient anemic rats.

We investigated the effects of fructooligosaccharides (FO)-feeding on the absorption of iron (Fe), calcium (Ca) and magnesium (Mg) and on the biochemical parameters in Fe-deficient anemic rats. Fe-deficient anemic rats were made by feeding an Fe-deficient diet for 3 weeks. Then these Fe-deficient rats were fed an experimental diet that contained one of two levels of Fe (15 or 30 mg/kg diet), in the form of ferric pyrophosphate, and one of two levels of FO (0 or 50 g/kg diet) for 2 weeks. After the rats were fed these experimental diets, FO-feeding increased the hematocrit ratio, the concentration of hemoglobin and the hemoglobin regeneration efficiency during the first week. Also, the apparent absorption of Fe was increased by FO-feeding. The levels of Fe in the diet did not affect the absorption of Ca and Mg. However, FO-feeding increased the absorption of Ca and Mg. FO-feeding lowered the pH and raised the solubility of Fe, Ca and Mg in the cecal contents, suggesting that those increasing effects of FO-feeding on absorption of these minerals is correlated with fermentation of FO in the large intestine, namely, the cecum and colon. We concluded that FO-feeding improved recovery from anemia and increased the absorption of Fe, Ca and Mg in Fe-deficient anemic rats.

Absorption↗

PubMed1995

Bassiatin, a new platelet aggregation inhibitor produced by Beauveria bassiana K-717.

A new platelet aggregation inhibitor, bassiatin, was isolated from the cultured broth of Beauveria bassiana which had been isolated from a soil sample collected in Yunnan province, China. The structure of bassiatin was determined to be (3S, 6R)-4-methyl-6-(1-methylethyl)-3-phenylmethyl-1, 4-perhydrooxazine-2,5-dione by NMR analysis, X-ray crystallographic analysis and chemical synthesis. Bassiatin inhibited ADP-induced aggregation of rabbit platelets with the IC50 being 1.9 x 10(-4) M.

Animals↗

PubMed1995

Roles of prostaglandin production and mitogen-activated protein kinase activation in hepatocyte growth factor-mediated rat hepatocyte proliferation.

Hepatocyte growth factor (HGF) and epidermal growth factor (EGF)-stimulated DNA synthesis in primary cultured rat hepatocytes. HGF-induced DNA synthesis was concentration-dependently inhibited by a cyclooxygenase inhibitor, indomethacin. BW755C, a dual inhibitor for cyclooxygenase and lipoxygenase activities, also inhibited hepatocyte growth. Prostaglandin E1 (PGE1), PGE2, and PGF2 alpha induced DNA synthesis even at such a low concentration as 5 nmol/L and potentiated [3H]thymidine incorporation induced by HGF in an additive manner. HGF caused arachidonic acid (AA) release and eicosanoid production. These events were detectable within 10 minutes after stimulation and lasted for at least 60 minutes. Furthermore, two proteins with approximately 40 kd were tyrosine phosphorylated by HGF. These proteins were identified as p42/p44 mitogen-activated protein (MAP) kinases by anti-MAP kinase immunoblots, which were known to activate cytosolic phospholipase A2 (cPLA2), a key enzyme in AA release. Activation of MAP kinases was detectable within 5 minutes after stimulation with HGF and lasted for at least 60 minutes. EGF-mediated DNA synthesis was also inhibited by the above cyclooxygenase inhibitors. EGF caused AA release and tyrosine phosphorylation of MAP kinases. These results suggest that HGF as well as EGF causes AA release, probably through activation of cPLA2 mediated by MAP kinases, and that PGs, metabolites of AA, might play a pivotal role in hepatocyte proliferation in an autocrine mechanism.

4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyraz↗

PubMed1995

[Investigation of Cryptomeria japonica pollinosis in Izu-Oshima].

We surveyed by questionnaire 4,673 residents of Izu-Oshima who were 15 or more years of age with regard to Cryptomeria japonica pollinosis. The response rate was 22.3%. In the early spring, nasal symptoms were reported by 8.9% of the respondents, ocular symptoms by 5.7%, and dermal symptoms by 8.1%. On scratch tests of symptomatic subjects, 13.8% were positive for Cryptomeria japonica antigen, and 33.3% had an IgE RAST score of 2 or more. The peak Cryptomeria japonica pollen concentrations between February and April 1990 were 118/cm2 on March 7 at the Northern Clinic and 271/cm2 at the Southern Clinic. A second questionnaire survey (response rate: 53.1%), designed to estimate the number of persons with Cryptomeria japonica pollinosis among all residents, revealed that 4.7% concurrently had three or more nasal symptoms and two ocular symptoms. By combining these results with those of a telephone survey of 100 randomly selected nonrespondents, 5.64% of all inhabitants were estimated to have suspected Cryptomeria japonica pollinosis.

Adolescent↗

PubMed1995

Morphological characters and disturbance of myofibril assembly in avian myoblasts fused with HVJ (Sendai virus).

We have been studying myogenic differentiation, especially the mechanism of myotube formation, using quail myoblasts transformed with a temperature-sensitive mutant of Rous sarcoma virus, QM-RSV cells. Myogenic differentiation of QM-RSV cells can be controlled by the incubation temperature. When cultured at 35.5 degrees C, a permissive temperature for the virus, the cells proliferate but do not differentiate, whereas, when incubated at 41.0 degrees C, a non-permissive temperature, they proceed through myogenic differentiation and then form myotubes. Presumptive QM-RSV cells cultured at 35.5 degrees C were fused with hemagglutinating virus of Japan (HVJ, Sendai virus) and the morphological characteristics of the fused myoblasts were compared with the myotubes formed spontaneously at 41.0 degrees C. The artificially fused myoblasts were tubular, like the spontaneously formed myotubes, and their tubular form was based on their microtubules. However, assembly of myofibrils was seen in spontaneously formed myotubes cultured at 41.0 degrees C, but not in artificially fused myoblasts cultured at 35.5 degrees C. Instead of myofibrils, round or rod-shaped structures were seen in artificially fused myoblasts. These structures were stained with rhodamine-labeled phalloidin but not anti-myosin antibody and were formed at 35.5 degrees C. On shift up to 41.0 degrees C, these structures disappeared, and myofibrils were formed, suggesting that the actin-positive structures in artificially fused myoblasts at 35.5 degrees C were disassembled forms of myofibrils.

Actins↗

PubMed1995

[Fall in the elderly and periventricular hyperintensity].

To investigate the relationship between brain white-matter changes and incidences of falling in the elderly, we studied periventricular hyperintensity (PVH) on brain MRI and history of falling in 73 neurologically normal elderly people. They were divided into 3 groups: group I; 9 prone to falling (mean ages 79 years), group II; 16 who felt mild gait disturbance without falling (75), group III; 48 asymptomatic controls (76). We evaluated white-matter changes as the sum of the length of PVH at 4 and 8 measuring points. Cognitive function and body sway were also evaluated. The frontal PVH was significantly larger in the group I than in the other two groups. Group I showed significantly lower Kohs' IQ than those in the other two groups. There was no difference in body sway among the groups. These results suggests that the propensity to falling in the elderly may be an initial symptom of frontal white-matter changes.

Accidental Falls↗