Search PubMed⌕ Search

Biomedical subjects

K Matsuno

Publications and source records attributed to K Matsuno.

At least 181 records · Page 10Linked to original sources
PubMed1994

Cytosolic interaction between deltex and Notch ankyrin repeats implicates deltex in the Notch signaling pathway.

Genetic data from Drosophila have suggested a functional relationship between the novel cytoplasmic protein encoded by the deltex locus and the transmembrane receptor encoded by Notch. We have demonstrated a direct interaction between these proteins from expression studies conducted in cultured cells, in yeast, and in the imaginal wing disc. deltex binds specifically to the Notch ankyrin repeats, a region that is crucial for Notch signaling and that constitutes the most conserved domain among Notch family members. In addition, we present a new Notch allele, Nsu42c, that is associated with a missense mutation within the fifth ankyrin repeat. In addition to representing a new class of viable Notch allele, this mutation behaves similarly to mutations of deltex and further implicates the ankyrin repeats in Notch function.

Alleles↗
PubMed1994

[Medical examination of workers exposed to lead in the Philippines].

The medical examination of workers exposed to lead was conducted as part of the activity of the Occupational Safety and Health Center (OSHC) Project in the Philippines (JICA Project). The subjects of the medical examination were 21 male and 193 female workers of a semi-conductor plant (abbreviated A company), 59 male and 6 female workers of a refrigerator manufacture (B company); 199 male workers of a storage battery manufacturer (C company); and 107 male and 6 female workers of a lead smelter (D company). Among the examination items were questions regarding occupational history, subjective complaints and objective signs, determination of blood lead levels, urine delta aminolevulinic acid levels, and examination for anemia. The survey was conducted from June to September in 1990. The following results were obtained: 1) The mean age of the workers ranged from 21.8 to 33.8 years. Those of companies A and B were younger than those of companies C and D. The mean employment duration of males at C company was 10.7 yr, and the longest among the four companies. That in both sexes for A company was 1.8 yr and the shortest among the above mentioned companies. 2) The blood lead geometric mean levels of companies C and D showed the highest concentration. The level in males of C company was 64.5 micrograms/dl and that of D company was 80.8 micrograms/dl. The level in females of A company was 9.9 micrograms/dl and the lowest in concentration. The urine delta aminolevulinic acid geometric mean levels were less than 6.0 mg/l in the four companies. There was no company having hemoglobin mean values less than 14.0 g/dl in males or less than 12.0 g/dl in females. 3) The proportion of blood lead levels of 60 micrograms/dl or more was 67.3% in males of C company, and 89.7% in males and 16.7% in females of D company. The proportion of urine delta aminolevulinic acid levels of 6 mg/l or more was 1.0% in females of A company, 20.1% in males of C company, and 43.0% in males of D company. The proportion of hemoglobin values less than 14.0 g/dl in males or less than 12.0 g/dl in females was 4.7% in females of A company, 1.7% in males of B company, 3.5% in males of C company, and 12.1% in males of D company.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1994

[Automated simultaneous measurements of activity and antigenicity of plasma antithrombin III].

Plasma antithrombin III activity and concentration were measured simultaneously on COBAS MIRA-S by colorimetry using a synthetic substrate and by immunoturbidimetry, respectively, in normal subjects (n = 30), in patients with liver disease (n = 37), and in those with thrombosis (n = 76). The activity/concentration ratio of plasma antithrombin III, in which concentration was represented as the ratio to the mean concentration for normal, was evaluated in each group. Results showed that the ratio was significantly lower in patients with liver diseases (0.76 +/- 0.18, mean +/- SD, p < 0.01) and in thrombotic patients (0.89 +/- 0.18, p < 0.01) than that in normal (1.07 +/- 0.06), demonstrating the predominance of antithrombin III molecules with low activity in the former groups. This simple and rapid (< 10 min) method is applicable for detecting such the constitutional change in plasma antithrombin III.

Adult↗
PubMed1993

Molecular cloning of a POU domain-containing factor involved in the regulation of the Bombyx sericin-1 gene.

The POU domain is a highly conserved region found in a number of transcription factors and products of developmental control genes. We report here the isolation and characterization of a POU domain-containing cDNA (POU-M1) from the middle silk gland of Bombyx mori. It encodes a protein with a POU domain identical to that of the Drosophila Cf1-a protein. By mobility shift and nuclease protection assays, the POU-M1 protein and the putative silk gland factor 3 (SGF-3) were found to interact in an indistinguishable manner with the SC region (positions -204 to -183) of the sericin-1 gene, a key cis-acting element involved in the regulation of the gene through the interaction with SGF-3. Antibodies raised against the synthetic oligopeptide corresponding to the COOH-terminal region of the putative POU-M1 sequence reacted specifically to both the POU-M1 protein and SGF-3. Northern blot hybridization and Western blotting revealed that POU-M1 expression is regulated both temporally and spatially during silk gland development. We conclude that the POU-M1 protein is SGF-3 and propose that the differential expression of the POU-M1 gene is probably involved in the transcriptional regulation of the silk protein genes.

Amino Acid Sequence↗
PubMed1993

Induction of mitochondrial chaperonin, hsp60, by cadmium in human hepatoma cells.

Mitochondrial dysfunction is readily induced by a low level of cadmium both in vivo and in vitro. The gene expression of mitochondrial hsp60 was induced in a dose- and time-dependent manner and also in parallel with the accumulation of cadmium in mitochondria. The levels of hsp60 mRNA increased with time until 18 h, while the induction of heat shock 70 (hsp70) gene peaked at 6 h and then declined. On the other hand, the levels of metallothionein mRNA reached to a plateau at 6 h and were maintained at this level continuously. These results suggest that the regulatory mechanism and/or the signals for hsp60 induction by cadmium are independent from those of hsp70 and metallothionein.

Biological Transport↗
PubMed1993

Determination of urinary 18-hydroxycortisol by isocratic normal-phase high-performance liquid chromatography.

A method for the determination of urinary 18-hydroxycortisol by high-performance liquid chromatography is described. Urinary samples were first mixed with an internal standard, 18-hydroxyprednisolone. 18-Hydroxycortisol and 18-hydroxyprednisolone, extracted by a Bond Elut column, were dehydrated by 1% (w/v) p-toluenesulphonic acid to the 11,18-epoxides. The epoxides were separated into two distinct peaks on a Resolve Silica column with a mobile phase of chloroform-methanol (100:2.5, v/v). The detection wavelength was 248 nm. The urinary 18-hydroxycortisol concentration was calculated from peak-height ratio of 11,18-epoxycortisol to 11,18-epoxyprednisolone. The linearity of the ratio was satisfactory in the range 12.5-300 ng per injection of 11,18-epoxycortisol. A specific increase of urinary 18-hydroxycortisol in patients with primary aldosteronism was demonstrated.

Chromatography, High Pressure Liquid↗
PubMed1993

Correlation between potentiation of neurogenic twitch contraction and benzomorphan sigma receptor binding potency in the mouse vas deferens.

The effects of sigma receptor ligands on the neurogenic twitch contraction in the ddY mouse vas deferens were studied. In functional studies, (+)-N-allylnormetazocine ((+)-SKF-10,047) and (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP) potentiated neurogenic twitch contractions in a concentration-dependent manner. The potentiation by each (+) enantiomer was significantly more potent than that by the respective (-) enantiomer. In addition, haloperidol and (+/-)-pentazocine also potentiated neurogenic twitch contractions. The order of potentiating ability was: haloperidol > (+/-)-pentazocine > (+)-3-PPP > (-)-3-PPP > (+)-SKF-10,047 > (-)-SKF-10,047. In contrast, other sigma receptor ligands, 1,3-di(2-tolyl)guanidine (DTG) and rimcazole, suppressed this twitch contraction. In addition, rimcazole significantly antagonized the (+)-SKF-10,047-induced potentiation at concentrations which did not affect contractions per se. Furthermore, binding studies showed that the kinetic parameters and the inhibitory potencies of sigma receptor ligands for the binding of [3H](+)-SKF-10,047 in the mouse vas deferens were similar to those in the guinea pig brain. The order of potency of sigma receptor ligands to potentiate the neurogenic twitch contraction in the mouse vas deferens was significantly correlated with the potency to inhibit [3H](+)-SKF-10,047 binding in both mouse vas deferens and guinea pig brain. These results indicate that sigma receptor ligands regulate the neurogenic twitch contraction, which is mediated by rimcazole-sensitive benzomorphan-type sigma receptors.

Animals↗
PubMed1993

Cytosolic free magnesium concentration in human platelets.

Although the magnesium ion (Mg2+) is considered to play an important role in cell activation, information is limited by the lack of suitable methods for measuring cytosolic free Mg2+ concentration ([Mg2+]i). We measured [Mg2+]i in resting and activated human platelets using a new fluorescent Mg(2+)-indicator, mag-fura-2. [Mg2+]i was 0.54 +/- 0.14 mM in resting platelets from 15 healthy volunteers. [Mg2+]i was elevated to 1.33 +/- 0.44 mM and 0.92 +/- 0.37 mM in platelets stimulated with thrombin and collagen, respectively. Increased Mg2+ was considered to be derived chiefly from intracellular Mg2+ mobilization. These results suggest that platelet activation is associated with the increase in [Mg2+]i. The estimation of [Mg2+]i using this method is useful for the investigation of mechanism for various cell activation.

Blood Platelets↗
PubMed1993

Increased plasma apolipoprotein E-rich high-density lipoprotein and its effect on serum high-density lipoprotein cholesterol determination in patients with familial hyperalphalipoproteinemia due to cholesteryl ester transfer activity deficiency.

Plasma apo E-rich HDL was studied in regard to its quantity and chemical composition in the members of a family with cholesteryl ester transfer activity deficiency, exhibiting familial hyperalphalipoproteinemia. The approach involved a simple precipitation method established in our laboratory. Serum apo E-rich HDL concentrations for two homozygous members were elevated up to 66 and 60 mg/dl in terms of cholesterol (normal, 6.7 +/- 2.3 mg/dl, n = 38), and to 9.4 and 10.8 mg/dl in terms of apo E (normal, 2.6 +/- 1.5 mg/dl, n = 38). The cholesterol/apo E ratio (mole/mole) of apo E-rich HDL was higher in two homozygotes (669 and 531) than in two cholestatic patients with elevated apo E-rich HDL (268 and 149) and in normal subjects (242 +/- 115, n = 38). Chromatographic studies of the serum from a homozygote showed enlargement of all HDL subclasses and apo E in the larger HDL subclass. These facts indicate that the increase of apo E-rich HDL in this disease occurs secondarily to the enlargement of HDL particles, which require substances to cover their cores, having expanded due to the accumulation of cholesteryl ester. The sera from the homozygotes gave HDL cholesterol concentrations which were remarkably discrepant among commercial precipitating reagents, because of the difference in recovery of apo E-rich HDL with these reagents.

Adult↗
PubMed1993

Effect of side-stream cigarette smoke on the hepatic cytochrome P450.

The effect of inhalation of side-stream cigarette smoke on the hepatic microsomal cytochrome P450 was investigated Rats were placed in a chamber of 0.1 m3 in volume, in which cigarettes were burned at the rate of 1, 3, or 5 cigarettes per h, 8 h/day for 5 days. Cytochrome P450 and NADPH-cytochrome c reductase showed no significant changes; however, cytochrome b5 increased significantly. On the other hand, the activity of aryl hydrocarbon hydroxylase (AHH) decreased in the rats treated with a high concentration of cigarette smoke. In order to study the changes of isoforms of cytochrome P450, western blot analyses were performed. The inductions of three kinds of isoforms, cytochromes P450IA1, IA2, and IIB1, were demonstrated immunochemically. However, there were disagreements between the results of the western blot analyses and the measurements of total cytochrome P450 content and AHH activity.

Animals↗
PubMed1993

Personal exposure to nitrogen dioxide from indoor heaters and cooking stoves.

The personal exposure to NO2 generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO2 filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO2 concentration during the study period was 13.5-13.7 micrograms/m3. Smoking and the usage of electric heaters did not affect the exposure to NO2. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO2 concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 micrograms/m3, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO2 levels during cooking were calculated to be 290 micrograms/m3. Using these calculated values of NO2 concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO2 were associated with the increase of urinary HOP/C.

Adult↗
PubMed1993

Biological monitoring of toluene and DNA polymorphism in humans.

The effects of genetic polymorphism in aldehyde dehydrogenase 2 (ALDH2) on alcohol intakes and toluene metabolism were studied in workers who handle toluene. The genotypes of ALDH2 were divided into three groups, which were the homozygous genotype of normal ALDH2 (NN), the homozygous genotype of an inactive one (DD) and the heterozygous genotype of normal and inactive ones (ND), using the polymerase chain reaction (PCR) method in a solution containing ddGTP. The alcohol intake of the DD group was very small. On the other hand, the alcohol intake of NN group was higher than that of DD group. That of ND group was about half way between those of NN group and DD group. The alteration of toluene metabolism by the polymorphism of ALDH2 was not clear because the exposure levels of the workers to toluene were low.

Adult↗
PubMed1993

Similar ameliorating effects of benzomorphans and 5-HT2 antagonists on drug-induced impairment of passive avoidance response in mice: comparison with acetylcholinesterase inhibitors.

Mice were trained to avoid electric shocks by means of step-down type passive avoidance learning tasks, and memory retention was measured 24 h after the training session. Memory impairment (amnesia) was produced by administering either p-chloroamphetamine (PCA), a serotonin (5-HT) releaser or scopolamine (SCOP), a muscarinic cholinoceptor antagonist, 30 min prior to the training session. Benzomorphans, 5-HT2 antagonists and acetylcholinesterase (AChE) inhibitors were administered immediately after the training session. PCA- but not SCOP-induced amnesia was attenuated by the post-training administration of two benzomorphans, (+)N-allylnormetazocine ((+)SKF-10,047) and (+/- )pentazocine ((+/- )PTZ). Similarly, PCA-induced amnesia was reversed by the post-training administration of 5-HT2 antagonists, ritanserin (RIT) and mianserin (MIA), but SCOP-induced amnesia was not. However, the AChE inhibitors, tetrahydroaminoacridine (THA) and physostigmine (PHY) attenuated both PCA- and SCOP-induced amnesia when administered immediately after the training session. These results indicated that benzomorphans and 5-HT2 antagonists have antiamnestic effects in mice, as do AChE inhibitors. In addition, it is interesting that the patterns of ameliorating effect of benzomorphans were similar to those of 5-HT2 antagonists, which differ from those of AChE inhibitors.

Acetylcholine↗
PubMed1993

In situ kinetics of acinar, duct, and inflammatory cells in duct ligation-induced pancreatitis in rats.

BACKGROUND: Acute pancreatitis remains a disease of uncertain pathogenesis. The resolution of the cellular events that underlie the development of pancreatitis may allow for significant advances in therapy. METHODS: A new experimental approach to acute pancreatitis in the rat, i.e., selective ligation of pancreatic ducts and immunohistochemical analysis of cellular kinetics using a panel of monoclonal antibodies, was devised. RESULTS: Immunostaining showed that the majority of the infiltrating cells bore macrophage-specific antigens (ED1-positive). Some neutrophils were also among the cellular infiltrate, but only a few T (OX19-positive) or B (His14-positive) lymphocytes were seen. At a later stage, more than half of the mononuclear cells in the stroma were neither macrophages nor lymphocytes, but possibly fibroblasts. In vivo labeling of proliferating cells with 5-bromo-2'-deoxyuridine and immunostaining showed active proliferation of duct epithelial and wall cells of the interlobular pancreatic duct on days 1 and 2, proliferation of nonacinar cells on days 1-4, and proliferation of acinar cells on days 2-28. CONCLUSIONS: These results indicate an important role of macrophages and the presence of complex processes of degeneration and regeneration in duct ligation-induced pancreatitis.

Animals↗
PubMed1993

A direct enzyme immunoassay for 18-hydroxycortisol in urine: a new tool for screening primary aldosteronism.

A microplate enzyme immunoassay has been developed for the measurement of 18-hydroxycortisol in urine. An antiserum was produced by immunization of rabbits with a 3-O-(carboxymethyl)oximino-18-hydroxycortisol-bovine serum albumin conjugate. IgG was isolated from the antiserum and was biotinylated. Newly synthesized p-nitrophenyl ester of the oxime was used for the preparation of steroid-horseradish peroxidase conjugate. After an incubation of diluted urine samples (or standards) and the steroid-enzyme conjugate with the biotinylated antibody, the resulting antigen-antibody complex was separated by adding a portion of the reaction mixture into the avidin-coated microtiter plate. Peroxidase bound to solid phase was measured colorimetrically. The standard curve was linear from 0.25 to 10 ng/well. Intra- and interassay coefficients of variation were 5.5-8.8 and 7.8-8.2%, respectively. The assay was specific except for 18-hydroxycortisone with minor cross reaction. Urinary 18-hydroxycortisol excretion ranged 836-7460 and 26-696 nmol/24 h, respectively, in patients with primary aldosteronism (n = 8) and in control subjects (n = 40). This simple and rapid (< 4 h) assay is suitable for screening patients with primary aldosteronism.

Animals↗
PubMed1993

Histochemical study of alkaline phosphatase in primary human brain tumors: diagnostic implications for meningiomas and neurinomas.

Histochemical analysis of frozen, thin sections revealed the distribution of alkaline phosphatase (ALPase) in 47 primary intracranial neoplasms in humans. The cytoplasm of meningioma cells exhibited the strongest ALPase reactivity. Pretreatment of these materials by levamisol indicated that the isozymes of ALPase had the characteristic liver-bone-kidney form. In meningiomas and astrocytomas, there was no particular relationship between ALPase activity and malignancy. In neurinomas, there was weak ALPase reactivity in a few neoplastic cells. These findings are suggestive of diagnostic implications for fibroblastic meningiomas and neurinomas at the light microscopic level.

Alkaline Phosphatase↗
PubMed1993

Proliferation kinetics of macrophage subpopulations in a rat experimental pancreatitis model.

The kinetics of rat macrophage proliferation in the inflamed pancreas was analysed using a duct-ligation pancreatitis model. We performed a double immunostaining of pancreatic cryosections using a panel of monoclonal antibodies to either macrophage-specific (ED1, ED2) or macrophage-related (CR3 and Ia) antigens in combination with a cell marker of DNA synthesis (5-bromo-2'-deoxyuridine, BrdU). One hour labeling with BrdU revealed each recorded macrophage phenotype to have a very high labeling index (12-28%), peaking on day 2 after induction of pancreatitis. The percentage of each proliferating phenotype also reached 20-40% of the total BrdU+ cells on day 2. The proliferating macrophages consisted of heterogeneous subpopulations including monocyte-like cells and resident macrophages. Their growth occurred in a relatively synchronized fashion, and seemed to be triggered by common proliferative signals.

Animals↗