PubMed Health⌕ Search

Biomedical subjects

Y Funae

Publications and source records attributed to Y Funae.

At least 181 records · Page 10Linked to original sources
PubMed1985

Resolution of proteins in the kidney stone matrix using high-performance liquid chromatography.

The organic matrix accounts for 2-3% of the total stone weight and has been considered to play a role in stone formation and growth. Thus far, fractionation of the matrix proteins has been insufficient due to low resolution and reproducibility. In this report the matrix proteins of 22 stones were resolved by means of high-performance liquid chromatography. Following pulverization, the organic matrix was obtained by dialysis against EDTA. The average content of nondialyzable extractable proteins was 1.6% of the total stone weight. Analysis of the matrix proteins with high-performance gel permeation liquid chromatography and high-performance ion-exchange liquid chromatography has indicated that the protein composition of the stone matrix is identical regardless of the mineral composition. The major component of the matrix proteins was identified as glycoprotein and/or proteoglycan from their absorption to a concanavalin A Sepharose column. Higher molecular weight matrix proteins seem to be polymers or condensation products, since they have been degraded into lower molecular weight subfractions by sodium dodecyl sulfate treatment.

Chromatography, High Pressure Liquid↗
PubMed1985

Rapid assay of N-butyl-N-(3-carboxypropyl)nitrosamine in rat organs and urine by high-performance liquid chromatography after derivatization.

The concentration of N-butyl-N-(3-carboxypropyl)nitrosamine (BCPN), which is the major metabolite of the carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), was measured in the urine, thymus, liver, kidney, and bladder of rats orally administered with BBN. Since BCPN is a carboxylic acid, it forms an ester with 9-anthryldiazomethane (ADAM), which is a fluorescent labeling agent highly sensitive to carboxylic acids. Thus, BCPN and ADAM were reacted at 40 degrees for 1 hr, and the resulting ester was separated and measured by high-performance liquid chromatography (HPLC) with a reverse-phase type column. The range of measurement was 0 to 40 micrograms/ml, and the coefficient of variation (CV) was 3.8%. When 0.025% BBN was given orally to rats in tap water, the BCPN concentration in the urine was very high at 220 micrograms/ml, while it was 0.15 microgram/100 mg in the wet tissues of the thymus, 0.35 microgram/100 mg in the liver, 0.40 microgram/100 mg in the kidney, and 1.2 microgram/100 mg in the bladder. The BCPN concentration in the bladder, in which tumors are induced by the administration of BBN, was thus higher than those in the other organs.

Animals↗
PubMed1985

Multiple forms of cytochrome P-450 from microsomes of rat liver, kidney, and lung resolved by high-performance liquid chromatography.

The amount of cytochrome P-450 in microsomes of rat kidney and lungs was 23 and 7%, respectively, of the amount in microsomes of the liver. HPLC profiles of solubilized microsomes showed that there were five or more forms of cytochrome P-450 in microsomes of kidneys and also of lungs of untreated rats. While 3-methylcholanthrene induced a new form of cytochrome P-450 in kidney and lung microsomes, phenobarbital caused no major change in the HPLC profiles of these microsomes.

Animals↗
PubMed1983

Rapid separation and measurement of rat urinary kallikrein by high-performance liquid chromatography with a continuous flow enzyme detector.

Rat urinary kallikrein was separated by high-performance liquid chromatography (HPLC) using an ion-exchange or gel-permeation column. Kallikrein activity was monitored continuously with peptidase or esterase activity using a post-reactor system directly adapted to HPLC. A PTFE helically coiled tube served as the enzyme reactor vessel. Four and three peaks with peptidase and esterase activity, respectively, were detected on application of normal rat urine.

Animals↗
PubMed1983

Specific and rapid assay of urinary oxalic acid using high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method was developed to determine the levels of oxalic acid in the urine. This acid was extracted from urine with tri-n-butyl phosphate and converted into the fluorescent derivative by esterification with 9-anthryldiazomethane (ADAM). The reaction mixture containing the oxalic acid derivative can be directly chromatographed on HPLC using octadecylsilane reverse-phase column monitoring with a fluorophotometric detector. A linear relationship was observed in the range from 1 to 100 micrograms/ml of standard oxalic acid dissolved in saline. Disease-free Japanese adults excrete 23.8 +/- 9.0 mg (mean +/- SD) of oxalic acid per day. This method should prove valuable for routine measurements of urinary oxalic acid as it is accurate, simple, and specific.

Anthracenes↗
PubMed1983

Plasma inactive renin in patients with diabetes mellitus: effects of standing and the relation to serum protease inhibitor.

In order to investigate the mechanisms of increased plasma inactive renin in diabetics with microvascular complications, changes in active and inactive renin with the progress of diabetes mellitus were studied, and effects of standing on inactive renin release and the relationship between plasma inactive renin and serum trypsin or protease inhibitors wee also studied. Inactive renin increased with the aggravation of diabetes mellitus, but active renin didn't show significant changes with the aggravation of diabetes mellitus. Active renin was significantly increased both in the healthy subjects and in the diabetic patients when they were in an upright position, but no significant change was observed in inactive renin. Serum trypsin in diabetics with retinopathy and nephropathy was lower than that in those with no clinical sign of microangiopathy, but the correlation between plasma inactive renin and serum trypsin was not significant. There was a significant correlation between plasma inactive renin and serum alpha 2-globulin (r = 0.52, p less than 0.01). Although plasma inactive renin was not significantly correlated with serum alpha 1-antitrypsin, there was a significant correlation between plasma inactive renin and serum alpha 2-macroglobulin (r = 0.61, p less than 0.01). These results show that the increased levels of plasma inactive renin observed with the development of diabetic microangiopathy are probably related to the altered plasma protein metabolism observed in patients with diabetes mellitus. However, it is not clear whether this altered protein metabolism is related to the conversion from inactive to active renin.

Adult↗
PubMed1983

[A new method to assay urinary oxalic acid using high-performance liquid chromatography].

Measurement of oxalic acid in urine has an important clinical significance because approximately 70% of human urinary calculi are composed of calcium oxalate. Different analytical methods of oxalic acid have been reported, but most are unsuitable for clinical use. Thus we developed a new method to assay oxalic acid in urine using high-performance liquid chromatography (HPLC). This acid was extracted from urine with tri-n-butyl phosphate and converted into the fluorescent derivative by esterification with 9- anthryldiazomethane (ADAM). The reaction mixture containing the oxalic acid derivative can be directly chromatographed on HPLC using an ODS reverse phase type column monitored with a fluorophotometric detector. A linear relationship was observed from 1 to 100 micrograms/ml of standard oxalic acid dissolved in saline. Healthy adults excrete 23.8 +/- 9.0 mg (mean +/- SD) of oxalic acid per day. This method should prove valuable for routine measurement of urinary oxalic acid as it is accurate, simple and specific.

Anthracenes↗
PubMed1981

Gel filtration profile of plasma active and inactive renin in normals and patients with nephrotic syndrome.

The molecular weight of plasma renin from healthy subjects and patients with nephrotic syndrome, in whom we previously reported that plasma inactive renin was increased, was studied by gel filtration. Activation was performed by acid treatment. The plasma from healthy subjects contains a low molecular weight from of renin (40 000) and a high molecular weight form which can be separated into two peaks of 52 000 and 60 000. After acid activation, renin activity was increased in the high molecular form but not significantly in the low molecular form. Although the increase of renin activity in the high molecular weight form after acid activation was larger in patients with nephrotic syndrome, the gel filtration profile was similar to that of healthy subjects.

Chromatography, Gel↗
PubMed1980

High-performance liquid chromatography technique for resolving multiple forms of hepatic membrane-bound cytochrome P-450.

Solubilized hepatic microsomal cytochrome P-450 from rats was resolved into 12-different heme-containing components by ion-exchange high-performance liquid chromatography. Separation was accomplished by the utilization of Anpac ion-exchange resin. Phenobarbital (PB) and 3-methylcholanthrene (3-MC) treatment of rats resulted in selective increases or decreases of specific components observed in the elution profile of solubilized microsomes prepared from untreated rats. Treatment with polychlorinated biphenyls increased peaks that were selectively increased by PB or 3-MC treatment. Proteins collected from the major peaks induced by PB or 3-MC treatment were found to retain spectral characteristics of cytochrome P-450. The recovered cytochrome b5 and NADPH-cytochrome c reductase retained spectral properties and enzymic activity, respectively. Purified P-450b obtained from PB-treated rats was found to cochromatograph with one of the peaks selectively induced by PB treatment. These results suggested that it is possible to separate membrane-bound proteins without dramatically altering their physical properties.

Animals↗
PubMed1980

Plasma active and inactive renin in patients with diabetes mellitus.

Plasma active and acid activated inactive renin was measured in healthy subjects and in patients with diabetes mellitus. The angiotensin I generated from the incubation of non-acidified plasma with pig renin substrate was expressed as plasma renin concentration (PRC) and that from acidified plasma was expressed as total renin concentration (TRC). The inactive renin concentration (IRC) was calculated as TRC minus PRC. With regard to plasma renin activity (PRA) and PRC, no significant difference was found between normal and diabetic groups. TRC and IRC in diabetics with no clinical sign of microangiopathy were 22.8 +/- 1.7 and 15.2 +/- 1.3 ng/ml/h (mean +/- SE), and these values were not significantly different from those in the healthy subjects (20.5 +/- 1.5 and 13.2 +/- 1.5 ng/ml/h). However, TRC and IRC in diabetics with retinopathy and clinical nephropathy was 38.8 +/- 3.4 and 30.7 +/- 3.2 ng/ml/h, and these values were significantly higher than those in the above two groups, respectively. Moreover TRC and IRC in diabetics with retinopathy and no clinical nephropathy was 33.8 +/- 5.7 and 24.9 +/- 5.5 ng/ml/h, and these values were significantly higher than those in the control group. IRC was not significantly correlated with fasting blood sugar and mean blood pressure levels, however however a significant correlation was found between IRC and BUN, and IRC and P.S.P. excretion in 15 minutes. These findings suggest that increased inactive renin in diabetes mellitus may be related to the progression of the renal lesions associated with diabetic microangiopathy.

Adult↗
PubMed1979

Effect of dithiothreitol of the reaction of renin and angiotensinogen.

Effects of several sulfhydryl reagents on the reaction of renin and angiotensinogen were investigated by measuring the production of angiotensin I. Renin and angiotensinogen were prepared from the kidneys of dogs and from plasma of nephrectomized dogs, respectively. The amount of angiotensin I generated was increased with application of dithiothreitol, dithioerythritol and 2,3-mercapto-1-propanol. The greatest enhancement of the generation of angiotensin I was observed with dithiothreitol. Dithiothreitol had no influence on renin activity, on radioimmunoassay for angiotensin I and the recovery of synthetic angiotensin I from the incubation medium. When heterologous angiotensinogen was used, a great enhancement of generation of angiotensin I was observed. Dithiothreitol did not accelerate the reaction following replacement of the natural substrate, angiotensinogen, with the synthetic tetradecapeptide as substrate. It is postulated that dithiothreitol augments angiotensin I generation by acting on the angiotensinogen and not on the renin.

Angiotensinogen↗
PubMed1978

Conversion between renin and high-molecular-weight renin in the dog.

Two forms of renin, one of mol.wt. 43,000 and the other 60,000, were found in the dog kidney. Conversion between the two forms of renin was reversible at neutral pH. Though the molecular weight of renin in kidney-cortex homogenate was 43,000, it was completely converted into high-molecular-weight renin in the presence of substances that react with thiol groups. On the contrary, stored renin in the granules was the form of normal size (mol. wt. 43,000) regardless of the absence or presence of such substances. The present experiments indicated that renin is stored in the granules as the form of normal size and might be converted into high-molecular-weight renin when it is released from the granules and attached to some substance in the soluble fraction of renal-cortical tissue.

Animals↗
PubMedDate not supplied

Differential alterations in levels of hepatic microsomal cytochrome P450 isozymes following intracerebroventricular injection of bacterial lipopolysaccharide in rats.

To investigate the effect of central inflammation due to bacterial infection, such as meningitis, on the activities of hepatic cytochromes P450 (CYPs), rats were injected intracerebroventricularly (i.c.v.) with 0.1 microg of bacterial lipopolysaccharide (LPS). The LPS i.c.v. injection significantly decreased the total P450 contents (by 30% of the levels of control rats treated with saline i.c.v.), the contents of CYP1A (48%), 2B (54%), 2C11 (37%) and 3A (40%) and related drug metabolizing activities, 7-ethoxycoumarin O-deethylation (36%), imipramine N-demethylation (41%) and erythromycin N-demethylation (33%) in liver microsomes 24 h after the treatment. In contrast, intraperitoneal (i.p.) injection of LPS at the same dose as i.c.v. (0.1 microg) did not significantly affect the hepatic microsomal contents of total P450 or the content of each individual CYP isozyme and its activity. CYP2D1 protein and the activity of imipramine 2-hydroxylase were not significantly decreased by LPS injection regardless of the route of administration. The inhibitory effects of 0.1 microg i.c.v. LPS on the activities of these CYPs were almost equal to those of 10 microg i.p. LPS, and 0.01 microg of i.c.v. LPS significantly decreased the activity of imipramine N-demethylase only. Therefore, the LPS i.c.v. injection resulted in CYP isozyme-selective inhibition at an ineffective dose when injected i.p.. It is suggested that a central inflammation, such as meningitis, differentially decreases the levels of hepatic CYP isozymes. A possible involvement is discussed of the central nervous system in this down-regulation.

Animals↗