Search PubMed⌕ Search

Biomedical subjects

J Watanabe

Publications and source records attributed to J Watanabe.

At least 469 records · Page 26Linked to original sources
PubMed1987

A possible mode of solubilization of coenzyme Q10 with HCO-60.

The redox level of [14C]coenzyme Q10 solubilized with HCO-60 in the livers of guinea pigs at 24 h after intravenous injection was approximately 1/4 (18.2% vs. 63.4%) of that of [14C]coenzyme Q10 solubilized with ethanol-water (1:5 by vol). Further, the redox level of coenzyme Q10 (Q10) solubilized with HCO-60 or ethanol-water was 20.2 or 82.3%, respectively, after a 30-min incubation in the liver cytosol. Q10 solubilized with HCO-60 was thus reduced only slightly in vivo or in vitro. The critical micelle concentrations of HCO-60 in the absence and presence of Q10 were 0.02 and 0.002% (w/v), respectively. The concentrations of HCO-60 micelles containing Q10 were estimated to be 0.0048% (w/v) in the incubation mixture with cytosol and 0.0041% (w/v) in blood circulation. These results suggest that HCO-60 micelles containing Q10 would remain more stable not only in blood circulation but also in tissues as compared with ethanol-water emulsion. A possible mode of solubilization of Q10 is discussed.

Animals↗
PubMed1987

Effects of urethane anesthesia and age on organ blood flow in rats measured by hydrogen gas clearance method.

Apparent blood flow rate in jejunum, kidney, liver or skeletal muscle was directly measured by the hydrogen gas clearance method in 7-week-old rats anesthetized with urethane at four dose levels (0.5, 0.8, 1.0 and 1.5 g/kg, i.p.). The apparent blood flow in each organ or tissue was reduced with the urethane dose. Jejunal blood flow was most sensitive to the dose-related decrease. Assuming that the organ (or tissue) to blood partition coefficient of hydrogen gas is unity and extrapolating the flow data to zero urethane dose for each organ, the flow rate values were almost comparable with the literature data in conscious rats. The applicability of the hydrogen gas clearance method to examine the effect of age on organ or tissue blood flow in rats was also discussed. Organs with relatively high sensitivity to aging were the stomach, jejunum and kidney.

Age Factors↗
PubMed1987

Variation in D-glucose uptake along the intestinal tract.

The variation in D-glucose uptake along the intestinal tract was examined by dividing the entire rat small intestine into 10 segments of equal length and by using everted sacs. The superiority of jejunum to ileum in D-glucose uptake, which is generally accepted, was supported by this work. It was attributed mainly to the variation in the maximal transport velocity of the Michaelis-Menten type carrier-mediated transport system with a clear kinetic border in the distal location of the small intestine, between segments 7 and 8. Information obtained in this study is useful for understanding and estimating the absorption process, or the time-course of absorption, of D-glucose as it passes down in the intestinal tract.

Animals↗
PubMed1987

Application of 3 alpha-hydroxysteroid dehydrogenase column to the determination of bile acids fractionated by high-performance liquid chromatography: advantage of pretreating human bile acids with Seppak C18 and piperidinohydroxypropyl Sephadex LH-20.

The analysis of bile acids in human bile was tried by high-performance liquid chromatography (HPLC). Bile acids in human bile were first prefractionated into free, glycine- and taurine-conjugated bile acids using a Seppak C18 cartridge and a piperidinohydroxypropyl Sephadex LH-20 (PHP-LH-20) column. Each fraction was then processed through a HPLC system consisting of a Zorbax ODS column and a 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) column. By these procedures the major 15 bile acids were clearly separated, and each bile acid of 10-125 ng was accurately analyzed. More than 400 times of analysis could be repeated on one 3 alpha-HSD column without loss of sensitivity. Thus the pretreatment through Seppak C18 and PHP-LH-20 made the HPLC analysis of human bile acids accurate and applicable to clinically obtained materials.

3-Hydroxysteroid Dehydrogenases↗
PubMed1987

Familial hyper-angiotensin converting enzyme (ACE)-emia: increased production of ACE by monocyte-macrophage.

We report here a familial clustering of elevated serum angiotensin converting enzyme (ACE) levels. The patient was a 58-year-old Japanese female. She had been in excellent health until the age of 45, when she noticed a decrease in visual acuity of her left eye. Despite intensive therapy under the diagnosis of occulusion of the central retinal vein, she lost her visual acuity at the age of 45. Thereafter, she has been in excellent health. The only abnormality found in this case has been a markedly elevated level of serum ACE (625 n mol/min/ml; normal range; 22-40 n mol/min/ml of serum). Her blood pressure was within normal limits (140/80 mmHg). There was no evidence for the diagnosis of sarcoidosis, Gaucher's disease, leprosy, hyperthyroidism, diabetic retinopathy, or liver disease. One of her two sisters also showed a marked increase in serum ACE activity (303 n mol/min/ml), and remarkably high levels of serum ACE (276 and 294 n mol/min/ml) were demonstrated in both of two sons of this sister. All the members of this family have been in excellent health. The serum ACE activity was activated by chloride and cobalt ions, and inhibited by EDTA, captopril and rabbit antiserum to purified human plasma ACE. Thus, our study showed a familial clustering of "hyper-ACE-emia", and the disorder appears to have been inherited as an autosomal dominant trait.

Cells, Cultured↗
PubMed1987

Production of colony-stimulating factor by sarcoid granulomas in vitro.

To examine whether sarcoid epithelioid cells of granulomatous lesions produce colony-stimulating factor (CSF), a growth factor of monocyte-macrophage series, the primary culture of sarcoid epithelioid cells was carried out from 16 biopsied lymph nodes which contained sarcoid granulomas, CSF activity was demonstrated at high titer in the conditioned media from all the epithelioid cell cultures. The conditioned medium of the epithelioid cell culture was harvested, concentrated by Amicon YM-10 membrane, and loaded on a Sephadex G-75 column. Two distinct peaks of CSF activity were noted just before and after bovine serum albumin region. The molecular weights were estimated at about 75,000 and 36,000, respectively. Both CSF fractions stimulated colony formation by murine bone marrow cells. The lower molecular weight CSF was active on human bone marrow cells, but the higher molecular weight CSF did not stimulate colony formation by human bone marrow cells.

Chromatography, Gel↗
PubMed1987

Primary pulmonary lymphoma demonstration of monoclonality by lymphocyte surface marker study.

We present here a case of small lymphocytic B cell lymphoma of the lung which developed in a 51-year-old Japanese man who was asymptomatic while his chest X-rays revealed slowly progressive infiltrative shadows. Findings of transbronchial lung biopsy suggested lymphoproliferative disorders and the diagnosis of B-cell lymphoma of the lung was established with lung specimen obtained by an open lung biopsy and through demonstration of monoclonal surface markers on lymphocytes in fresh frozen lung sections. Diagnostic value of surface marker analysis is emphasized.

Antibodies, Monoclonal↗
PubMed1986

Metabolism of 25-hydroxycholecalciferol in human promyelocytic leukemia cells (HL-60). Isolation and identification of (5Z)- and (5E)-19-nor-10-oxo-25-hydroxycholecalciferol.

Human promyelocytic leukemia cells incubated with 25-hydroxy[26,27-methyl-3H] cholecalciferol (1 microCi) or non-radioactive 25-hydroxycholecalciferol (550 micrograms) produced significant quantities of two vitamin D3 metabolites. The two metabolites were isolated and purified by methanol chloroform extraction and a series of chromatographic procedures. The metabolite purification and elution positions on these columns were followed by radioactivity and their ultraviolet absorption at 310 nm. The two metabolites have been unequivocally identified as (5Z)- and (5E)-19-nor-10-oxo-25-hydroxycholecalciferol by ultraviolet absorption spectrophotometry, mass spectrometry, Fourier-transform infrared spectrophotometry and co-chromatography with synthetic compounds on a high-performance liquid chromatograph. (5E)- but not (5Z)-19-nor-10-oxo-25-hydroxycholecalciferol was able to induce HL-60 cell phenotypic and functional differentiation. However, these two metabolites of 25-hydroxycholecalciferol did not bind specifically to the chick intestinal 3.7 S. receptor protein for 1 alpha,25-dihydroxycholecalciferol. The precise biological role of these metabolites is as yet unclear.

Animals↗
PubMed1986

Structure and drug inducibility of the human cytochrome P-450c gene.

A human genomic clone (lambda hP-450mc-1), highly homologous to the rat cytochrome P-450c gene, was isolated and analyzed for the complete nucleotide sequence. The gene structure coincides with that of a recently reported human gene isolated from genomic DNA of a human breast carcinoma cell line, MCF-7 [Jaiswal, A.K., Gonzalez, F.J. & Nebert, D.W. (1985) Nucleic Acids Res. 13, 4503-4520] with notable exceptions in the first intron: a 320-base-pair fragment is inserted and a 650-base-pair fragment is deleted in the gene examined in the present study. The 320-base-pair insert appears to contain a moderately repetitive sequence (approx. 140 copies) in the human genome. The 650-base-pair fragment, present in intron 1 of the reported sequence, is dislocated in the lambda hP-450mc-1 to about 10(4) base pairs upstream from the putative transcription initiation site. The results of Southern blot analysis using human total DNA were compatible with the gene structure of lambda hP-450mc-1. A fusion gene, which was constructed by ligating the 5' flanking region of the gene to the structural gene for prokaryotic chloramphenicol acetyltransferase (CAT), inducibly expressed the CAT activity in mouse Hepa-1 cells in response to administered methylcholanthrene, indicating that the isolated human gene is indeed of methylcholanthrene inducibility.

Acetyltransferases↗
PubMed1986

Age-dependence in capacity-limited uptake kinetics of propranolol by isolated rat hepatocytes.

Overall initial uptake rates of propranolol by isolated rat hepatocytes were analyzed to give both apparently linear and saturable processes. The rate constant for the linear transport process in 7- and 24-week old rats was approximately 0.01 ml X sec-1 X (10(6) cells)-1. For the capacity-limited uptake process of propranolol, the kinetic parameters in 7-week-old rats, were estimated as Vmax = 0.609 microgram X (10(6) cells)-1 X sec-1 and Km = 8.17 micrograms/ml, whereas in 24-week-old rats, Vmax = 0.348 microgram X (10(6) cells)-1 X sec-1 and Km = 9.40 micrograms/ml. The overall uptake rate, when the hepatocytes were incubated with 20 micrograms/ml of propranolol, was reduced with age of the rats between 5 or 7 and 24 weeks and declined gradually thereafter, A higher cell to medium concentration ratio for the initially, net transported component of propranolol in relatively young (5- to 11-week-old) rats suggested an age-dependent saturable uptake process. This was supported by the direct comparison of the saturable uptake rates between 7 and 24 weeks. Therefore, the saturable sinusoidal transport (i.e. saturable uptake by the hepatocytes) may be considered one of the most important mechanisms determining the age-dependence in the intrinsic hepatic clearance of this drug noted in our previous report.

Aging↗
PubMed1986

Age-dependent propranolol clearance in perfused rat liver.

The effect of age on the hepatic clearance of propranolol was studied by perfusing the liver isolated from 3- to 104-week-old rats. Propranolol levels in the recirculating perfusate declined biexponentially with time in all age groups. When the liver isolated from 7-week-old rats was perfused with propranolol (1 microgram/ml, 100 ml), hepatic clearance of this drug by the perfused liver (CLperf) increased from 0.589 to 1.14 ml X min-1 X (g liver)-1 with the increase of the perfusion flow rate from 1.0 to 2.0 ml X min-1 X (g liver)-1, confirming evidence of "perfusion-limited" hepatic clearance for this drug. Furthermore, there was no initial concentration(dose)-dependence in CLperf up to 2.5 micrograms/ml (i.e. 250 micrograms/organ). The effect of age on CLperf was then investigated by perfusing the isolated liver with 1.0 micrograms/ml propranolol at 2.0 ml X min-1 X (g liver)-1. Elimination of this drug from the perfusion medium was relatively rapid in 5- to 7-week-old rats, yielding the highest CLperf in these relatively young rats [approximately 1.0 to 1.1 ml X min-1 X (g liver)-1]. In contrast, CLperf values in both immature and older rats were 0.5 ml X min-1 X (g liver)-1 or less. The in vitro intrinsic hepatic clearance estimated in 5- and 7-week-old rats was about ten times as high as that in 104-week-old rats.

Aging↗
PubMed1986

Peri- and postnatal development of heterogeneity in the amounts of endoplasmic reticulum in mouse hepatocytes.

The surface density and area per cell of the endoplasmic reticulum (ER) in periportal and perihepatic hepatocytes from male ddY mice, "17-, 18-, and 19-day-old fetuses," "newborn and 1-, 5-, 10-, and 20-day-old animals," and "adult animals" were analyzed by quantitative electron microscopy. The surface density of rough ER was not significantly different between periportal and perihepatic cells in all age groups examined, except for 19-day-old fetuses in which the value was greater in periportal cells than perihepatic cells. The surface density of smooth ER and total (rough and smooth) ER did not significantly differ between the periportal and perihepatic cells from 17-day-old fetuses to 5-day-old animals. In 10- and 20-day-old and adult animals, the values of smooth and total ER were greater in perihepatic cells than in periportal cells. When the data were expressed as area per cell, the patterns of subacinar distributions hardly differed, but age-related changes differed considerably from the patterns seen in the surface density data. The differences were generally caused by the increase in hepatocyte volume between 20 days of age and adulthood, especially in perihepatic cells, and by the changes in volume during the perinatal period. The results show that differences in the surface density and area per cell of smooth and total ER between periportal and perihepatic hepatocytes evident in adult animals are not present in fetal and newborn animals but arise during postnatal development.

Age Factors↗
PubMed1986

Plasma membrane reregionalization in cultured mouse hepatocytes.

The cytochemical localization of alkaline phosphatase (ALPase) activity and the autoradiographic distribution of glucagon receptors were examined in the plasma membrane of cultured mouse hepatocytes. After 24 hours of culture, ALPase activity was exclusively localized on the plasma membrane in areas of cell-cell contact, and glucagon receptors were more numerous in the plasma membrane at the periphery of re-formed cell trabeculae. These results indicate that plasma membrane regionalization of hepatocytes, lost by cell isolation, reappeared during culture. The cells maintained this plasma membrane regionalization until 48 hours of culture. By 72 hours of culture, however, ALPase activity was seen on the external surface of all regions of plasma membrane, and the glucagon receptors decreased markedly in number and became scattered in all regions of plasma membrane. Thus, the re-formed plasma membrane regionalization disappeared in the cells by 72 hours of culture.

Alkaline Phosphatase↗
PubMed1986

Cytochemical and biochemical glucose 6-phosphatase activity in skeletal muscle cells of mice.

Cytochemical and biochemical glucose 6-phosphatase (G6Pase) activity and fiber type composition were studied in soleus (SOL) and gastrocnemius (GC) muscles of mice. The SOL is a red muscle which contains numerous type I fibers (60%) and relatively few type II fibers (40%). The GC is a white muscle which contains numerous type II fibers (90-100%) and very few type I fibers (0-10%). In the SOL and GC, cytochemical G6Pase activity was localized in the sarcoplasmic reticulum, lateral elements of triads, myonuclear envelope, and in the endoplasmic reticulum and nuclear envelope of endothelial cells. Differential centrifugation showed that G6Pase activity was recovered in the 105,000g pellet (microsomal fraction). Histochemical enzyme activity in type II fibers was slightly higher than that in type I fibers. Biochemical G6Pase activity in the GC was significantly higher than that in the SOL. The possible functional significance of G6Pase in skeletal muscles was discussed.

Animals↗