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Biomedical subjects

K Kasuya

Publications and source records attributed to K Kasuya.

At least 37 records · Page 2Linked to original sources
PubMed1998

An enzyme-linked immunosorbent assay and reference ranges for bisphosphoglycerate mutase in human erythrocytes.

We established an enzyme-linked immunosorbent assay (ELISA) system for the determination of human bisphosphoglycerate mutase (BPGM) protein content in human erythrocytes using a polyclonal anti-BPGM antibody, we determined reference ranges for BPGM protein content, synthase activity, and specific activity in human erythrocytes. We produced a recombinant human BPGM (rBPGM) by gene manipulation using E. coli and then obtained the polyclonal antibody by immunizing rabbits with purified rBPGM. The reproducibility of the ELISA was in an acceptable range with a coefficient of variation under 1.5%. The ELISA was reliable in the range of 0.1 to 10 ng/mL. The polyclonal anti-rBPGM antibody did not show any cross-reaction with recombinant human B type phosphoglycerate mutase, which is highly homologous to rBPGM. The ELISA was found to be practical for the determination of BPGM protein content in human erythrocytes. The mean BPGM protein content was 56.3+/-9.7 microg/mL in whole blood (mean+/-SD, n = 50). The ELISA can be used to examine various hematologic disorders with abnormal red cell size and cell counts, and to detect BPGM enzymopathy in human erythrocytes.

Adult↗
PubMed1997

Cloning of the gene for poly(3-hydroxybutyric acid) depolymerase of Comamonas testosteroni and functional analysis of its substrate-binding domain.

A poly(3-hydroxybutyric acid) (PHB) depolymerase gene of Comamonas testosteroni YM1004 was cloned on Sau3AI fragment from genomic DNA into Escherichia coli DH5. Nucleotide sequence analysis dedicated a 1539 bp open reading frame encoding a protein 513 amino acid with a putative 25 residue signal peptide for secretion. The deduced amino acid sequence was very similar to that of PHB depolymerase of Comamonas sp. In order to understand the characteristics of substrate-binding domain of the depolymerase, we constructed its glutathione S-transferase (GST) fusion protein and investigated the ability of adsorption on PHB single crystals by using gold-conjugated antibody and transmission electron microscopy. The fusion protein adsorbed on PHB single crystals tightly and homogeneously, suggesting that binding domain contributes to the adsorption of enzyme on solid PHB without site specificity.

Amino Acid Sequence↗
PubMed1997

p53 protein overexpression and K-ras codon 12 mutation in pancreatic ductal carcinoma: correlation with histologic factors.

The correlation of p53 protein overexpression and the K-ras codon 12 mutation with histologic type, grade of cytologic atypia, depth of invasion and other histologic prognostic factors was studied in paraffin sections from 43 ductectatic- and 70 solid-type pancreatic ductal carcinomas. Overexpression of p53 was found in 23.3% (10/43) of ductectatic carcinomas (17.2% of intraductal and 35.7% of invasive carcinomas) and in 61.4% (43/70) of solid carcinomas. In ductectatic cancers, p53 overexpression was detected in 14.8% (4/27) of carcinomas with low-grade atypia (CAL), 50.0% (5/10) of carcinomas with high-grade atypia (CAH) and in 16.7% (1/6) of mixed low- and high-grade cancers. In the last group, expression was restricted to an area of CAH. In solid cancers, p53 overexpression did not differ by histologic type or grade. Overexpression of p53 and K-ras mutations did not correlate with histologic prognostic factors (lymphatic, venous and perineural invasion, and lymph node metastasis) in ductectatic and solid cancers or depth of invasion of solid carcinomas. Our data suggest that p53 alteration occurs at an early intraductal stage of solid carcinoma, irrespective of cellular atypia, but is low in ductectatic CAL and becomes higher in ductectatic CAH. K-ras mutation, present in a high percentage of tumors of all groups and not correlating with the factors above, showed no changes in frequency with tumor progression.

Carcinoma↗
PubMed1997

Biochemical and molecular characterization of the polyhydroxybutyrate depolymerase of Comamonas acidovorans YM1609, isolated from freshwater.

Comamonas acidovorans YM1609 secreted a polyhydroxybutyrate (PHB) depolymerase into the culture supernatant when it was cultivated on poly(3-hydroxybutyrate) [P(3HB)] or poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] as the sole carbon source. The PHB depolymerase was purified from culture supernatant of C. acidovorans by two chromatographic methods, and its molecular mass was determined as 45,000 Da by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The enzyme was stable at temperatures below 37 degrees C and at pH values of 6 to 10, and its activity was inhibited by diisopropyl fluorophosphonate. The liquid chromatography analysis of water-soluble products revealed that the primary product of enzymatic hydrolysis of P(3HB) was a dimer of 3-hydroxybutyric acid. Kinetics of enzymatic hydrolysis of P(3HB) film were studied. In addition, a gene encoding the PHB depolymerase was cloned from the C. acidovorans genomic library. The nucleotide sequence of this gene was found to encode a protein of 494 amino acids (M(r), 51,018 Da). Furthermore, by analysis of the N-terminal amino acid sequence of the purified enzyme, the molecular mass of the mature enzyme was calculated to be 48,628 Da. Analysis of the deduced amino acid sequence suggested a domain structure of the protein containing a catalytic domain, fibronectin type III module as linker, and a putative substrate-binding domain. Electron microscopic visualization of the mixture of P(3HB) single crystals and a fusion protein of putative substrate-binding domain with glutathione S-transferase demonstrated that the fusion protein adsorbed strongly and homogeneously to the surfaces of P(3HB) single crystals.

3-Hydroxybutyric Acid↗
PubMed1997

Elimination of apoptotic granulosa cells by intact granulosa cells and macrophages in atretic mature follicles of the guinea pig ovary.

Phagocytic cells disposing of dying granulosa cells in the atretic ovarian follicles were morphologically studied in guinea pig ovaries at various stages of estrous cycle. Epon embedded semithin sections stained with toluidine blue were observed with a light microscope, and ultrathin sections were examined under a transmission electron microscope. Frozen sections were processed for acid phosphatase histochemistry and MR-1 (a monoclonal antibody against guinea pig macrophages) immunohistochemistry. In animals during the estrus period (days 1 and 2) as well as the second half of the estrous cycle (days 11 and 16), there were numerous mature follicles in which massive groups of granulosa cells were undergoing apoptosis. Two kinds of phagocytic cells were identified in these follicles of the initial stage of atresia: one was intact granulosa cells ingesting neighboring dead granulosa cells, and the other was large round cells identified as macrophages due to their strong acid phosphatase activity and MR-1 immunoreactivity. Mature follicles of the advanced stage of atresia were frequently recognized during the metestrus period (days 4 and 5). Small stellate cells were regarded as surviving granulosa cells, while large round cells showing intense reactions for acid phosphatase and MR-1 were identified as macrophages. This study demonstrates that both intact granulosa cells and macrophages participate in the elimination of apoptotic granulosa cells in atretic mature follicles of the guinea pig ovary, and remain even in the advanced stages of atresia.

Acid Phosphatase↗
PubMed1996

Adsorption kinetics of bacterial PHB depolymerase on the surface of polyhydroxyalkanoate films.

The kinetics of adsorption and hydrolysis by an extracellular PHB depolymerase from Alcaligenes faecalis were studied at 37 degrees C on the surface of five types of polyhydroxyalkanoate (PHA) films. The films of poly[(R)-3-hydroxybutyrate] (P(3HP)), poly(3-hydroxypropionate) (P(3HP)), and poly(4-hydroxybutyrate)(P(4HB)) were hydrolyzed by the enzyme, while the films of poly[(S)-2-hydroxypropionate)(P(2HP)) and poly(6-hydroxyhexanoate)(P(6HH)) were not eroded. The PHB depolymerase with binding and catalytic domains adsorbed on the surface of all PHA films used, and the adsorption kinetics were found to obey the Langmuir isotherm. The cross-area per one molecule of enzyme binding to the surface of PHA film was estimated to be 17 +/- 8 (nm2/molecule). It has been concluded that the binding domain of enzyme is non-specific for the binding to the surface of PHA film, while the active site in a catalytic domain is specific for the hydrolysis of PHA molecules.

Adsorption↗
PubMed1996

Perinatal changes in bovine SEGI's caps with special reference to their endocrine cells migrating into the lamina propria.

Large aggregations of endocrine cells at the top of villi in the upper small intestine, discovered by SEGI (1935) in human fetuses and hence called SEGI's caps, have been known to occur also in bovine and porcine fetuses. Using bovine fetuses and newborns, this study aimed to clarify the fate of and changes in the SEGI's cap during the perinatal period. Immunocytochemistry was performed for CgA and PGP 9.5 as markers of the endocrine and nervous elements concerned. In the second trimester in bovine fetuses, numerous endocrine cells were confirmed, by CgA immunocytochemistry, to gather in the epithelium on the top of almost every duodenal villus, either in a single layer or accumulating in a rounded cell mass. They persisted until birth, though decreasing in number during the third trimester. In these fetal periods the endocrine cells came to be invaginated into the lamina propria, and to be separated from the epithelium. They were attached by nerve fibers and shifted to the base of the villi and to the intercryptal tissue. The endocrine cell aggregations at the villous tips rapidly disappeared within three days after birth. The intraepithelial endocrine cells (paraneurons) decreased in their immunoreactivity for CgA after they shifted into the lamina propria, whereas they increased in their immunoreactivity for PGP 9.5 while descending the villous interstitium. Using immunocytochemistry for PGP 9.5, we were able to trace the descent of the endocrine cells in association with nerve fibers. Microscopic images were obtained supporting the possibility that the endocrine-type cells eventually might be taken up by the intramural plexuses of Meissner and Auerbach. Furthermore, the fetal and perinatal intestine revealed enlarged solitary endocrine cells and authentic neurons, as well as their intermediate types, in the villous and intercryptal interstitium. The present results indicate that the SEGI's caps in cattle are best developed in the second trimester of the fetal life, and do not support a hypothesis that the endocrine sensor cells in the caps principally function at the time of birth, especially for responding to the advent of colostrum. The endocrine or paraneuronal elements of the SEGI's cap appear to migrate into the interstitium to obtain more neuron-like features. A possibility that they may be incorporated in the intramural ganglia and further be transformed into neurons awaits further investigation.

Animals↗
PubMed1995

Microdialysis measurement of intracerebral somatostatin in the goat.

A microdialysis sampling technique for the intracerebral measurement of somatostatin (SS) in extracellular fluid was examined in the goat. The microdialysis probe (70-mm shaft, 0.5 mm outer diameter) contained at its tip a 4-mm length of copolymer dialysis membrane (20 kDa cut-off). Artificial cerebrospinal fluid (artificial CSF) was pumped through the probe tip at a rate of 4 microliters/min with a batter-driven syringe pump, and effluent fractions of dialysate (120 microliters) were collected every 30 min. An in vitro recovery test showed that changes in the SS concentration in dialysate were highly correlated (r = 0.95, P < 0.01) with those in the external medium, and the relative recovery averaged 2.0%. As a validation for in vivo microdialysis, trails were conducted with conscious behaving goats wherein the inflow dialysate was changed transiently from artificial CSF with low potassium (2.5 mM) to a solution of 300 mM KCl. Potassium-induced depolarization around the probe tip located in the preoptic area and in the hypothalamus induced an increase in SS concentrations in dialysate at each location. In the most remarkable response, the concentrations of SS were increased 6-fold and 11-fold in the first and second 30-min fractions, respectively, compared with prepotassium concentrations. These results suggest that intracerebral SS levels in extracellular fluid could be estimated from conscious behaving goats by the use of our intracerebral microdialysis system.

Animals↗
PubMed1995

The process of apoptosis in follicular epithelial cells in the rabbit ovary, with special reference to involvement by macrophages.

Using rabbit ovaries, this study investigated the fate of follicular epithelial cells undergoing apoptosis in follicle atresia, especially in atretic Graafian follicles. This is the first report to apply the TUNEL method and histochemistry for acid phosphatase in order to demonstrate macrophages immigrating into the follicles to eliminate the apoptotically dead epithelial cells. At initial stages of atresia, a few epithelial cells solitarily revealed the condensation of nuclear chromatin characteristic of apoptosis, simultaneously reacting positive to the TUNEL method. At advanced stages, chromatin condensation and separation as well as cytoplasmic fragmentation spread to the entire follicular epithelium. In such an advanced atretic follicle, large round cells appeared in the follicular lumen; these could be identified as macrophages by their morphologies and positive reactions for acid phosphatase. These macrophages were adhering to and internalizing apoptotic epithelial cells and their fragments until the lumen became completely free of dead cells and fragments.

Acid Phosphatase↗
PubMed1992

Left ventricular dysfunction and HLA Bw52 antigen in Takayasu arteritis.

Heart disease is the main cause of death in patients with Takayasu arteritis. It has been reported that this disease is closely related to the presence of HLA Bw52 antigen. To assess the correlation between this antigen and left ventricular involvement, we studied 40 patients with Takayasu arteritis, 21 with and 19 without Bw52, using Tl-201 stress myocardial scintigraphy and echocardiography. Those with Bw52 had a significantly higher incidence of abnormal electrocardiographic findings (67% vs 26%; P < 0.05) and of aortic regurgitation (52% vs 11%; P < 0.05). The echocardiographically determined interventricular septal wall thickness plus left ventricular posterior wall thickness (25 +/- 8 vs 17 +/- 3 mm; P < 0.01) and the left ventricular mass (257 +/- 132 vs 142 +/- 51 g; P < 0.01) were significantly increased in the patients with Bw52. Scintigraphically determined perfusion abnormalities were significantly more frequent in those with Bw52 (76% vs 32%; P < 0.05). These observations indicate that patients with Takayasu arteritis and Bw52 antigen have a more severe left ventricular involvement than the patients without that antigen. The left ventricular impairment may account for the poor prognosis of Takayasu patients with Bw52.

Adult↗
PubMed1991

Thallium-201 stress scintigraphy in Takayasu arteritis.

Thirty-eight women with Takayasu arteritis were studied using thallium-201 stress myocardial scintigraphy to assess the prevalence and pathophysiology of the perfusion abnormality. Twenty (53%) had abnormal scintigraphic findings (group A). Abnormal scans were divided into 3 groups: permanent defects in 6, reversible defects in 7 and slow washout in 7. The remaining 18 patients had normal scintigrams (group N). Group A had a tendency to be older and to have a high prevalence of complicated significant aortic regurgitation. Interventricular thickness plus left ventricular posterior wall thickness (26 +/- 7 vs 17 +/- 2 mm, p less than 0.01) and left ventricular mass (267 +/- 121 vs 133 +/- 39 g, p less than 0.01) were all greater in group A on echocardiography. The mean value of the central aortic pressure in systole was 170 +/- 15 mm Hg in the 7 catheterized patients in group A. Coronary ostial stenoses were present in 2 group A patients who showed reversible defects on scintigrams. These data indicate that the abnormal perfusion detected by imaging in patients with Takayasu arteritis was responsible for a decrease in coronary reserve or myocardial damage, or both, due to long-standing systemic hypertension or aortic regurgitation. Coronary artery disease should be considered if a reversible defect is present.

Adult↗
PubMed1991

[Study of intermittent intra-arterial infusion chemotherapy in liver metastases from squamous cell carcinoma].

There are few reports about the methods, amounts, and kinds of dosage about intermittent intra-arterial chemotherapy of liver metastases from primal pathological type's squamous cell carcinoma. Because they are less than liver metastases from adenocarcinoma of colon or stomach. Although it is important of other factors about the operative method of primary focus and metastases of the other parts, it is possible that those cases obtained the good prognosis and protected liver failure, if those liver metastases could be controlled well. In our department from January 1987 to December 1989, 9 cases of inoperative liver metastases of squamous cell carcinoma (esophagus: 4 cases, larynx: 3 cases and cervix of uterus 2 cases) were treated of intra-arterial infusion chemotherapy of FAM (5Fu 500 mg/week, ADM 30 mg/4 weeks and MMC 4 mg/2 weeks) and CDDP methods (only CDDP 10 mg/week). Cases of esophagus carcinoma were treated with FAM method. On the CT-scan one of the cases showed the reduction rate of more than 50% and was a Progressive Response (PC), and the SCC tumor marker decreased in 2 cases. However, 2 other cases died of liver failure. Cases of larynx were treated with FAM and CDDP methods. However, on the CT-scan all of the cases showed No Change (NC) nor decrease in SCC. But thinking of prognosis FAM was better than CDDP. Cases of cervix of uterus were treated with the FAM and CDDP methods. FAM was not different than the CDDP in the prognosis and effect.

Aged↗
PubMed1982

Studies of glycogen-induced inflammation of mice. Dynamics of inflammatory responses and influence of antiinflammatory drugs and protease inhibitors.

The intraperitoneal injection of glycogen in the mouse resulted, shortly thereafter, in the accumulation of 14-23 million neutrophils in the peritoneal cavity and a four-fold increase in the numbers of circulating neutrophils. Preceding the influx of leukocytes, the exudation of plasma proteins and the chemotactic activity for mouse neutrophil in vitro increased in the peritoneal fluid. Among various protease inhibitors examined, chymostatin alone suppressed the plasma protein exudation. Indomethacin and dexamethasone reduced the accumulation of white cells and protein exudation. These nonsteroidal and steroidal antiinflammatory drugs were equally effective whether given simultaneously with or 60 min before glycogen or whether administered intraperitoneally or orally. Colchicine showed a suppressive effect on the leukocyte accumulation but enhanced the protein exudation.

Animals↗