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Biomedical subjects

K Uchida

Publications and source records attributed to K Uchida.

At least 865 records · Page 48Linked to original sources
PubMed1993

Preferential degradation of protein-bound (ADP-ribose)n by nuclear poly(ADP-ribose) glycohydrolase from human placenta.

Poly(ADP-ribose) glycohydrolase, extensively purified to homogeneity from nuclei of human placenta, is composed of a single polypeptide with a molecular mass of 71,000 daltons on sodium dodecyl sulfate-polyacrylamide gel. Judging from its physico-chemical and catalytic properties, the enzyme is similar to the nuclear glycohydrolase (glycohydrolase I), but not to the cytoplasmic glycohydrolase (glycohydrolase II) that has been purified from guinea pig liver (Tanuma, S., Kawashima, K., and Endo, H. (1986) J. Biol. Chem. 261, 965-969; Maruta, H., Inageda, K., Aoki, T., Nishina, H., and Tanuma, S. (1991) Biochemistry 30, 5907-5912). The rates of hydrolysis of (ADP-ribose)n bound to various proteins by the purified nuclear glycohydrolase were higher than those of the corresponding free polymers. Kinetic analyses revealed that the enzyme had more activity toward poly(ADP-ribose) bound to histone H1 or to poly(ADP-ribose) polymerase than toward oligo(ADP-ribose) bound to cytoplasmic proteins from mitochondria or mRNA ribonucleoprotein although the Km and Vmax values were dependent on the chain length (n). In contrast, cytoplasmic glycohydrolase purified from human erythrocytes was more active toward oligo(ADP-ribose) (n = 2.6 or 4.2) bound to the cytoplasmic proteins than to poly(ADP-ribose) (n = 14.6) bound to histone H1, and their kinetic parameters of glycohydrolase II were rather dependent on the acceptor molecules for (ADP-ribose)n. These results suggest that poly(ADP-ribose) glycohydrolase I may play an important role in regulation of poly(ADP-ribosyl)ation levels on chromosomal proteins in nuclei.

Amino Acids↗
PubMed1993

Inactivation of glucose-6-phosphate dehydrogenase by 4-hydroxy-2-nonenal. Selective modification of an active-site lysine.

Incubation of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides with 4-hydroxy-2-nonenal (HNE) results in a pseudo first-order loss of enzyme activity. The pH dependence of the inactivation rate exhibits an inflection around pH 10, and the enzyme is protected from inactivation by glucose 6-phosphate. Loss of enzyme activity corresponds with the formation of one carbonyl function per enzyme subunit and the appearance of a lysine-HNE adduct. The data presented in this paper are consistent with the view that the epsilon-amino group of a lysine residue in the glucose 6-phosphate-binding site reacts with the double bond (C3) of HNE, resulting in the formation of a stable secondary amine derivative and loss of enzyme activity. We have described a mechanism by which HNE may, in part, mediate free radical damage. In addition, a method for the detection of the lysine-HNE adduct is introduced.

Aldehydes↗
PubMed1993

Histochemical analysis of blood group antigens in human sublingual glands and pancreas. An application of high-performance liquid chromatography to estimate the quantity of galactose liberated from tissue sections by alpha-galactosidase digestion.

Using immunostaining with monoclonal antibodies (mAbs) from three different sources as well as anti-B lectin, GSAI-B4 staining and alpha-galactosidase digestion, blood group B antigens were localized and analysed in tissue sections of sublingual glands from blood group B and AB individuals. Quantitative analysis of galactose was simultaneously carried out on the supernatant enzyme solution used for treating tissue sections by high-performance liquid chromatography (HPLC). In addition, galactose liberated from the pancreas tissues of blood group B and AB individuals was also estimated by HPLC analysis in order to compare the content of antigens. mAb-B(H079) and GSAI-B4 reacted uniformly with the mucous cells from blood group B and AB secretors. On the other hand, other mAbs-B(B006 and A582) recognized the antigen in a limited number of cells or was even negative in some cases of blood group AB individuals. Only mAb-B(H079) recognized the B antigens in mucous cells from non-secretors. Digestion with alpha-galactosidase resulted in the consistent appearance of H and Le(b) antigens in the mucous cells of all the secretors examined, although the reduction of staining intensity with anti-B reagents was not so marked. Le(y) antigens also appeared in some cases after the enzyme digestion. In non-secretors, Le(b) and Le(y) antigens, but not H antigens, appeared in some mucous cells following enzyme digestion. HPLC analysis of galactose revealed that alpha-galactosidase can specifically liberate the terminal galactose residues of B antigens, and no marked difference was present in the content of liberated galactose from mucous cells of sublingual glands among the individuals investigated (8.5-11.7 nmoles cm-2). No galactose was detected in samples from the sublingual glands of non-secretors, and only a trace amount of galactose was detected in the samples from pancreas tissues. These results suggest that the observed difference in the reactivity of different reagents with each tissue site can be ascribed to both quantitative and qualitative heterogeneity of B antigens.

Blood Group Antigens↗
PubMed1993

Analysis of regions essential for the function of chromosomal replicator sequences from Yarrowia lipolytica.

Two DNA segments exhibiting ARS (autonomously replicating sequence) activity in the dimorphic yeast Yarrowia lipolytica were cloned from its chromosome on an integrative LEU2 plasmid. These ARS segments, designated Y1ARS1 and Y1ARS2, conferred on the hybrid plasmids high transformation efficiency and enabled extrachromosomal transmission of the plasmids in 1 or 2 copies per yeast cell under selective conditions. Deletion analysis showed that at least 728-1003 bp for Y1ARS1 and 1377-1629 bp for Y1ARS2 were required for full function. Both of these regions contained two 10/11 matches to an ARS core consensus in Saccharomyces cerevisiae, whereas neither was similar to the S. cerevisiae centromere sequence. Significantly, both Y1ARS elements contained at, or close to, their boundaries a 13 bp sequence, 5'-TATATTCAAGCAA-3', which resembles the cleavage site for topoisomerase II in Drosophila. A central 524 bp ClaI fragment of Y1ARS2 contained four stretches of a 17 bp direct repeat sequence, 5'-GAAAAACAAAAACAGGC-3', and exhibited the electrophoretic behavior typical of bent DNA.

Base Sequence↗
PubMed1993

Olivary degeneration after cerebellar or brain stem haemorrhage: MRI.

Magnetic resonance (MR) images of seven patients with olivary degeneration caused by cerebellar or brain stem haemorrhages were reviewed. In four patients with cerebellar haemorrhage, old haematomas were identified as being located in the dentate nucleus; the contralateral inferior olivary nuclei were hyperintense on proton-density- and T2-weighted images. In two patients with pontine haemorrhages, the old haematomas were in the tegmentum and the ipsilateral inferior olivary nuclei, which were hyperintense. In one case of midbrain haemorrhage, the inferior olivary nuclei were hyperintense bilaterally. The briefest interval from the ictus to MRI was 2 months. Hypertrophic olivary nuclei were observed only at least 4 months after the ictus. Olivary degeneration after cerebellar or brain stem haemorrhage should not be confused with ischaemic, neoplastic, or other primary pathological conditions of the medulla.

Aged↗
PubMed1993

The role of thyrotropin-releasing hormone (TRH) in the pathogenesis of water-immersion stress in rats--inhibition of TRH release from the stomach by atropine, ranitidine or omeprazole.

The role of thyrotropin-releasing hormone (TRH) in the development of gastric erosions and ulcers induced by water-immersion stress was studied. Intraperitoneally administered bethanechol induced a decrease in the gastric wall immunoreactive TRH (ir-TRH) concentrations and an increase in gastric juice ir-TRH concentrations in a dose-related manner, while atropine induced an increase in gastric wall ir-TRH concentrations and a decrease in gastric juice ir-TRH concentrations under non-stress condition. Intraperitoneally administered omeprazole did not influence gastric wall ir-TRH concentrations but elevated gastric pH. Water-immersion stress induced a decrease in gastric wall ir-TRH concentrations and an increase in gastric juice ir-TRH concentrations with a decrease in gastric pH prior to ulcer formation. Pretreatment with atropine or ranitidine inhibited the development of stress ulcers, reduced changes in ir-TRH concentrations in the gastric wall and gastric juice, and induced an increase in gastric pH. Omeprazole inhibited stress ulcer formation and changes in gastric wall and gastric juice ir-TRH concentrations. These results suggest that TRH release from the stomach wall into gastric juice is of importance in the pathogenesis of stress ulcer and that its release is mediated by both muscarinergic and histaminergic (H2) systems. Furthermore, omeprazole has an inhibitory effect on TRH release under stress ulcer.

Animals↗
PubMed1993

Deglycation of glycated proteins with hydrazine analogues.

Glycated human serum albumin (glc HSA) and glc proteins in back hairs from diabetic rats were deglycated by incubation with hydrazine or aminoguanidine (guanylhydrazine) at physiological temperature (37 degrees C). Glc HSA decreased by 35% with 0.2 M hydrazine at day 20 and by 56% with 0.1 M aminoguanidine at day 10. The glc proteins in hairs decreased by 40-50% and 70-77% with hydrazine and aminoguanidine at more than 0.1 M by day 20, respectively. The deglycation of glc protein with aminoguanidine was slower than that with hydrazine. The present result suggests that the inhibitory effects by aminoguanidine on the late Maillard reaction may include a decrease in the level of glc proteins (Amadori compounds) due to deglycation.

Animals↗
PubMed1993

Jaw movements and EMG activities of limb-licking behavior during grooming in rabbits.

Jaw movements and masticatory muscle activity were recorded in freely moving rabbits during limb-licking, chewing, and drinking. The limb-licking movement was characterized by rhythmical jaw movement and digastric burst and relatively small masseter activity. The mean cycle time was 292 ms +/- 11.0 (mean +/- SE: n = 7) and was longer than that in chewing (267 ms +/- 20.8, p < 0.01) or drinking (208 ms +/- 15.2, p < 0.01). Jaw movements in the frontal plane of the ingestive behaviors coincided with those reported in previous studies; however, that of the licking movements was featured here. The basic cycle included; a) an opening stroke in which the mandible moved downward and laterally, b) a lateral excursion stroke in which the mandible moved medially and either upward or downward, and c) a closing stroke in which the mandible moved upward to the closing position. During opening, the digastric activity on the working side was determined to be larger than that on the other side (p < 0.001).

Animals↗
PubMed1993

Immunohistochemical detection of proliferating cell nuclear antigen (PCNA)/cyclin in human prostate adenocarcinoma.

Tissue specimens from 12 patients with adenocarcinoma of the prostate and 7 patients with benign prostate hypertrophy were stained by an indirect immunoperoxidase method using antiproliferating cell nuclear antigen (PCNA) monoclonal antibody. The PCNA labeling index was determined by counting the number of PCNA-labeled cells in the tissue sections. Average PCNA labeling index of the benign prostate hypertrophy was 1.2 +/- 0.5%. Poorly differentiated tumors averaged 7.6 +/- 3.9% labeling versus 4.6 +/- 1.3% in moderately differentiated tumors, and well differentiated tumor in the series had a PCNA labeling index of 2.5 +/- 0.9%. The PCNA labeling indices for atypical hyperplasia were 1.9, and 4.1%, respectively. Our preliminary results suggest that the measurement of PCNA labeling index in prostate cancer may prove to be a new objective and quantitative assay of biological potential of individual tumor.

Adenocarcinoma↗
PubMed1993

Inhibition by a new bisphosphonate (YM175) of bone resorption induced by the MBT-2 tumour of mice.

A new bisphosphonate, disodium dihydrogen (cycloheptylamino) methylene bisphosphonate monohydrate (YM175), was compared with 3-amino-1-hydroxypropylidene-1, 1-bisphosphonate (AHPrBP) and 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) in terms of its effect on tumour induced osteolysis using a bladder tumour in mice (MBT-2). The method consisted of inoculating tumour cells subcutaneously (SC) over the calvaria in mice, resulting in a local tumour causing fragmentation of the bone. The compounds were active not only when administered preventively before establishment of bone resorption, but also in an inhibitory fashion once the variables were already under the influence of the tumour. This osteolysis was evaluated by measuring the increased area of bone resorption in reduced opacity to radiograph and histology. The results showed the following sequence of potency: YM175 > AHPrBP = HEBP. This inhibition was obtained with no apparent effect on the growth of the MBT-2 tumour. YM175 appears to be an interesting new bisphosphonate with possible clinical application.

Animals↗
PubMed1993

HLA-DRB1 matching as a recipient selection criterion in cadaveric renal transplantation.

We retrospectively examined the effect of HLA-DRB1 matching at the DNA level compared with serological HLA-DR matching on acute rejection and graft survival in patients who underwent primary cadaveric renal transplantation. For patients with serological HLA-DR zero mismatch, the incidence of acute rejection in patients with zero DRB1 mismatch (3/20; 15%) was significantly lower than in those with one or two DRB1 mismatches (10/21; 48%). Five-year graft survival in patients with zero DRB1 mismatch was 100%, whereas that in those with one or two DRB1 mismatches was 76%, although the difference was not statistically significant. The fact that HLA-DRB1 matching at the DNA level influenced incidence of graft rejection after cadaveric renal transplantation is analogous to results in living-related renal transplantation. It is suggested that avoidance of mismatching for DRB1 alleles at the DNA level in recipient selection of cadaveric renal transplantation leads to an improvement of graft outcome.

Adult↗
PubMed1993

HTLV-1-associated myelopathy/tropical spastic paraparesis-like rats by intravenous injection of HTLV-1-producing rabbit or human T-cell line into adult WKA rats.

We intravenously injected Ra-1 cells or MT-2 cells into female adult WKA rats. Spastic paraparesis mainly in the hind-limbs was observed in 1 out of 2 Ra-1 cell-injected WKA rats and in 3 out of 8 MT-2 cell-injected WKA rats 20-27 months after injection. The main neuropathological finding was symmetrical white matter degeneration with mononuclear cell infiltration of the spinal cord, similar to that of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, and degeneration of nerve roots and peripheral nerves. Antibodies against HTLV-1 antigens were detected in plasma and cerebrospinal fluid from these HAM/TSP-like rats. HTLV-1 provirus was detected from the peripheral blood mononuclear cells of one of these rats 20 months after injection. Interestingly, spastic paraparesis was not observed in F344 rats.

Animals↗
PubMed1993

Metamorphic changes in glycolipids and myelin proteins and 2',3'-cyclic nucleotide 3'-phosphohydrolase in bullfrog and axolotl brains.

The metamorphic changes in levels of glycolipids and myelin proteins and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) in the brains of bullfrog tadpoles, adult frogs, and axolotls were investigated, with particular emphasis on myelin maturation. The concentrations of cerebroside, sulfatide, and galactosyldiacylglycerol gradually increased from the onset of prometamorphosis throughout the active metamorphic period and then greatly increased after metamorphosis was completed. The ratio of glucocerebroside to galactocerebroside increased greatly in the prometamorphic period and then rapidly decreased to the frog level during the climax period. The fatty acid compositions of cerebroside and sulfatide showed a developmental change, with 24:1 being more predominant in the later metamorphic stage. The proportion of hydroxy fatty acids increased up to the onset of the prometamorphic stage and thereafter remained constant at approximately 50% of the total. The CNP activity remained unchanged throughout metamorphosis at 60% that in frog myelin and increased in the adult frog. The composition of tadpole myelin proteins remained constant during metamorphosis, with large basic protein being the most abundant, and in the frog, proteolipid protein and large basic protein were present in comparable amounts. The two adult forms of axolotl, i.e., the neotenous and metamorphosed forms, exhibited almost identical myelin constituents, and CNP activity in the neotenous form amounted to one-fifth that in the bullfrog. These results indicate that active biosynthesis of myelin marker components occurs as metamorphosis proceeds, but more pronounced changes of myelin components occur after metamorphosis is completed.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗
PubMed1993

[A healthy carrier of verotoxin-producing Escherichia coli, who was detected by periodic feces examinations].

Verotoxin-producing Escherichia coli (VTEC) was rapidly detected by the PCR method in one of the 9 feces samples. They were collected from the people who had been cooking meals for patients on a periodic feces examination on November 25, 1992. It was confirmed by PCR that the isolate had both VT1 and VT2vh toxic genes and showed cytotoxicity on Verocells. In this case, the isolate was highly susceptible to common antibiotic agents, it was removed by the administration of tosfulaxacin. Some isolates which had the same properties as those of the strain described in "VITEK GNI card" and the antimicrobial susceptibility and VT toxin types, were detected in 2 of the 3 members of her family, they were healthy carriers and did not have any subjective symptoms such as diarrhea or abdominal pain. In order to detect Verotoxic genes, the sample of feces preincubated for 3 h in trypticase broth was subjected to PCR. We recommend that this method is much more useful because of rapid detection and identification of VTEC compared with the classical culture method.

Adult↗
PubMed1993

Use of the conjugate of disulphated ursodeoxycholic acid with p-aminobenzoic acid for the detection of intestinal bacteria.

The disulphate ester of ursodeoxycholyl-p-aminobenzoic acid (PABA-UCDA) was synthesised and compared with PABA-UDCA for its use in detection of intestinal bacteria. This compound, PABA-UDCA disulphate, had characters in common with PABA-UDCA in that it was deconjugated by cholylglycine hydrolase to release free PABA and bacteria that split glycocholic acid deconjugated PABA-UDCA disulphate. Further, in rat experiments urinary excretions of PABA were measured for six hours after oral administration of 15 mg PABA-UDCA disulphate. Ten control rats excreted (mean (SE) 188.2 (13.6) micrograms of PABA; 10 rats with an intestinal stagnant loop excreted more (530.1 (30.1) micrograms; p < 0.001): whereas 10 rats in each of three groups pretreated by oral administration of various antibiotics excreted less (polymixin B+tinidazole, 4.9 (1.6) micrograms; kanamycin, 31.0 (4.7) micrograms; clindamycin 40.9 (5.5) micrograms; p < 0.001). By contrast with PABA-UDCA, PABA-UDCA disulphate was not actively absorbed from any part of the small intestine in everted gut sac experiments, and showed poor recovery from bile after its intraileal instillation in rats. This indicated that PABA-UDCA disulphate is a single pass type substance in the gut and its oral administration test reflects the sum of the activities of bacteria in the small intestine and colon. The disulphate was easily soluble in water and this allowed its application in an in vitro test involving PABA-UDCA disulphate incubation with intraperitoneal pus (PABA-UDCA disulphate incubation test) from patients with peritonitis. This test was carried out on six patients with peritonitis, and the severity of bacterial peritonitis was expressed quantitatively. From the results obtained PABA-UDCA disulphate was considered a good material to detect intestinal bacteria.

4-Aminobenzoic Acid↗
PubMed1993

A novel colorimetric method for determination of glycated protein based on 2-keto-glucose release with hydrazine.

We tried to measure glycated proteins by a novel method based on colorimetry of 2-keto-glucose which is released from the glycated protein (ketoamine) on heating with hydrazine. Reaction conditions were optimized with glycated human serum albumin (glc HSA) as a model compound. Ketoamine reacted quantitatively with hydrazine on heating at 100 degrees C for 0.5 h, followed by heating with phenylhydrazine at 60 degrees C for 1 h. Glucose interference with the assay was eliminated by preincubation of the sample with glucose oxidase at 37 degrees C for 0.5 h. Time courses for the coloration of glc HSA and human serum showed a profile similar to that of N-p-tolyl-D-isoglucosamine under optimized reaction conditions. The lower limit for the assay of glc HSA was 0.7 microM. The serum level of glycated proteins measured by the present method correlated well with that (fructoamine value, microM) measured by the conventional method (nitroblue tetrazolium-reducing method) (r = 0.92, n = 35). In conclusion, the present method is a novel, highly sensitive and reliable one for measuring glycated proteins in biological samples.

Colorimetry↗