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K Fukui

Publications and source records attributed to K Fukui.

At least 235 records · Page 13Linked to original sources
PubMed1993

Effects of media conditioned by a non-metastasizing human salivary gland adenocarcinoma cell clone and metastasizing clones from salivary gland and various other tissues on the proliferation, migration and protease production of bovine aortic endothelial cells in vitro.

We demonstrate the role in tumor-associated angiogenesis of factors released into conditioned medium (CM) from in vitro human salivary gland cell clones with biological phenotypes ranging from non-metastasizing to metastasizing. A non-metastasizing human salivary gland adenocarcinoma cell clone HSGc and its subclone with metastatic potential (Gc2-100 cl-1) were employed. We also used metastasizing cell clones obtained by explant cultures of organs of Gc2-100 cl-1 tumor-bearing nude mouse. The proliferation and migration of bovine aortic endothelial (BAE) cells were significantly stimulated by the addition of CM obtained from Gc2-100 cl-1 and metastasizing cell clones, while CM from HSGc was ineffective. When the effect on protease secretion by BAE cells was examined, CM from Gc2-100 cl-1 and metastasizing cell clones inhibited the secretion of type IV collagenases by BAE cells much more than did CM from HSGc. These findings, therefore, may imply that Gc2-100 cl-1 and metastasizing cell clones secrete angiogenic factors that stimulate not only the proliferation and migration of endothelial cells but also the formation of basement membrane components necessary for the reconstruction of new blood vessels at migrated sites of endothelial cells by preventing the degradation of basement membrane component, type IV collagen.

Adenocarcinoma↗
PubMed1993

Role of plasminogen activators, metalloproteinases and the tissue inhibitor of metalloproteinase-1 in the metastatic process of human salivary-gland adenocarcinoma cells.

An in vitro system has been established in which conversion from non-metastasizing to metastasizing adenocarcinoma cells can be induced, and subsequently subjected to analysis of the expression of proteases and tissue inhibitor of metalloproteinases-1 (TIMP-1). A human salivary-gland adenocarcinoma cell clone HSGc, with no metastatic ability, was exposed to N-methyl-N-nitrosourea (MNU). Following exposure to MNU, cells with altered morphology were cloned. Upon s.c. inoculation into nude mice, MNU-treated HSGc clones formed metastatic foci in various organs, and then 5 metastasizing clones were isolated. Evaluation of expression of tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (uPA), metalloproteinases and TIMP-1 was performed by means of enzyme immunoassay, zymogram, or immunoblot. MNU-treated HSGc and metastasizing clones were found to secrete high levels of tPA, while HSGc produced undetectable levels of this enzyme. Expression of uPA was not observed in any of the cell clones. When the secretion of gelatinolytic enzymes was examined, metastasizing clones produced higher levels of 57- and 32-kDa, but not of 92- or 72-kDa gelatinases, as compared to HSGc cells. Although TIMP-1 was detected in all cell clones, metastasizing clones secreted less TIMP-1 than HSGc cells; in addition, one metastasizing clone produced TIMP-1 with a molecular weight distinct from that of 28-kDa TIMP-1. Our results suggest that the acquisition of metastatic ability by human salivary-gland tumor cells is closely associated with increased secretion of several metalloproteinases as well as decreased or altered TIMP-1 expression.

Adenocarcinoma↗
PubMed1993

Antigenic properties of Campylobacter rectus (Wolinella recta) major S-layer proteins.

The antigenic properties of the surface layer (S-layer) proteins of various Campylobacter rectus strains including 24 clinical isolates and the type strain ATCC 33238 were examined. S-layer proteins were extracted from whole cells by acid treatment according to the method of McCoy et al. (Infect. Immun. 11, 517-525, 1975). The acid extracts from 23 of the isolates and ATCC 33238 contained two major proteins with molecular masses of 130 kDa and 150 kDa, both of which were identified as subunits of the S-layer after comparison with the protein profiles of acid-treated (S-layer-deficient) cells. An S-layer protein from one isolate (CI-808) demonstrated a different molecular mass (160 kDa). Both the 150-kDa proteins of ATCC 33238 and isolate CI-306 and the 160-kDa protein of CI-808 were purified by ion-exchange chromatography in the presence of urea. In Ouchterlony immunodiffusion experiments with these purified proteins and rabbit antiserum raised to each purified protein, both common and strain-specific antigenic determinants were identified in the C. rectus S-layer proteins.

Antigens, Bacterial↗
PubMed1993

Protection of cardiac myocytes from hypothermic injury by cardiac fibroblasts isolated from neonatal rat ventricle.

In this study, we evaluated the functional and biochemical effects of cardiac fibroblasts (CFs) on cardiac myocytes (CMs) incubated under hypothermic conditions. CMs and CFs were isolated from neonatal rat ventricles and cultures of myocytes only or myocytes in coculture with CFs were established. A CM and CF concentration of 2.5 x 10(5) cells/ml was chosen and the optimum proportion of CF was determined to be 33% (ml CM:ml CF) as follows: 6:0 (group C-a), 4:0 (group C-b), 4:2 (group M-F). On the fourth day of culture, cells were incubated at 4 degrees C for 6, 12, 18, 24, 36 and 48 hr. After each incubation, creatine phosphokinase ((PK) and lactate dehydrogenase (LDH) were measured in the medium, and then the cells were cultured for an additional 24 hr at 37 degrees C to evaluate the recovery of the CM contracting rate. In groups C-a and C-b (n = 6 each), the recovery ratio of CM contracting rate decreased at 18 hr (C-a, 59.0; C-b, 55.6% of control; i.e., contracting rate prior to hypothermic incubation), reaching null levels at 48 hr. However, group M-F (n = 6) showed a significantly increased recovery at 18 hr (95.7%, P < 0.05; at 48 hrs, 27.6%). Release of CPK and LDH in groups C-a and C-b increased gradually by 24 hr and showed a marked increase at 48 hr (C-a, 114.3 x 10(-2), 194.2 x 10(-2); C-b, 81.6 x 10(-2), 118.6 x 10(-2) IU/flask, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Immunocytochemical localization of prostaglandin endoperoxide synthase in the bovine intestine.

The localization of prostaglandin (PG) endoperoxide synthase in bovine intestine was examined immunocytochemically with polyclonal antibody raised against PG endoperoxide synthase purified from bovine seminal glands. The most intense positive staining reaction for the enzyme was present in mast cells. Mast cells were found to be widely distributed in the intestinal wall, and were particularly numerous in the lamina propria. Most of the mast cells in the lamina propria of the intestinal villi were elongated and oriented with their long axis parallel to the plane of the absorptive epithelium. In whole mount preparations of jejunal villi, mast cells were seen to form a two-dimensional network in the lamina propria. In addition to mast cells, smooth muscle cells of the inner circular muscle layer and muscularis mucosae, nerve cells and fibers, endothelial cells of arterioles, and serosal epithelial cells also showed faint to moderate staining for the enzyme. These results suggested that mast cells are the major source of PGs in the bovine intestinal wall. The characteristic arrangement of mast cells in the intestinal villi may be related to their functions in this portion of the bovine intestine.

Animals↗
PubMed1993

A cardiac myocyte culture system as an in vitro experimental model for the evaluation of hypothermic preservation.

In cardiac transplantation, the donor heart is exposed to severe hypothermic and ischemic conditions. The purpose of the present study was to evaluate the functional and biochemical effects on cardiac myocytes cultured under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days, then incubated (1.5 x 10(6) myocytes/culture flask) for 24 h in media at 4, 10, 15, 20, and 37 degrees C. In addition, myocytes were incubated at 4 degrees C for 6, 12, 18, 24, 36, and 48 h. After each incubation, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) were measured and the myocytes then cultured for an additional 24 h at 37 degrees C to evaluate the recovery of the myocyte beating rate. The recovery ratio of the myocyte beating rate following 24 h of varying temperature incubations was complete for the 10, 15, 20, and 37 degrees C groups, although it was markedly decreased in the 4 degrees C group, at 25.1% of the control; taken as the beating rate prior to hypothermic incubation. The release of CPK and LDH in the 4 degrees C group showed a three-fold increase compared to the other four groups, with a CPK of 147.2 mIU/flask and a LDH of 487.5 mIU/flask. The recovery of the beating rate for varying time incubations at 4 degrees C was complete for the 6- and 12-h groups, but decreased significantly in the other four groups, being 59.0% at 18 h, 28.2% at 24 h, 16.3% at 36 h, and 0% at 48 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Computer-aided automatic identification of rice chromosomes by image parameters.

An automatic, computer-aided method for identification of rice chromosomes was developed based on image parameters obtained by image analysis. Numerical data of the 360 condensation patterns (CPs) or the density profiles of rice chromosomes obtained from 30 chromosomal spreads of haploid rice were subjected to three different discrimination methods for identifying the chromosome: (1) discrimination flow chart, (2) linear discrimination functions, and (3) minimum distance classifier based on standardized Euclidean distance. Discrimination based on the minimum distance classifier resulted in the correct identification of more than 92% of the rice chromosomes. The first and second methods gave a correct identification of 91% and 84%, respectively. It is concluded that the 12 rice chromosomes in most spreads could be identified by a computer.

Chromosomes↗
PubMed1993

In vitro evaluation of diltiazem on hypothermic injury to immature myocytes.

The purpose of the present study was to evaluate the functional and biochemical effects of diltiazem (DTZ) on cardiac myocytes incubated under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days with MCDB 107 medium. Then, myocytes (12.5 x 10(5) myocytes/flask) were incubated at 4 degrees C for 24 hours in media with or without DTZ at concentrations of 0 M (group C), 10(-7) M (Group D1), 10(-6) M (group D2), 10(-5) M (group D3), or 10(-4) M (group D4). After 24 hours at 4 degrees C, CPK and LDH were measured. The myocytes were then cultured for 24 hours at 37 degrees C to evaluate the recovery of the myocyte beating rate. In group C (n = 7), the recovery ratio of the myocyte beating rate was 29.9% of control (beating rate prior to hypothermic incubation). Groups D1 and D2 (n = 7 each) had approximately the same recovery ratios as group C (24.0% and 24.7%, respectively); however, groups D3 and D4 (n = 7 each) showed no beating rate recovery. Release of CPK and LDH in group C was 112.3 mIU/flask and 457.4 mIU/flask, respectively. Groups D1 and D2 showed no significant differences in both enzymes compared to group C. However, the levels of CPK were significantly higher in group D4 (203.3, p < 0.05), and LDH levels were significantly higher in groups D3 and D4 (669.3, p < 0.05; 883.4, p < 0.02). In conclusion, DTZ showed no protective effects on hypothermic injury to immature cardiac myocytes; moreover, it accelerated cellular injury at the concentrations of 10(-5) and 10(-4) M both functionally and biochemically. Therefore, diltiazem may not be suitable for cardiac preservation during the neonatal period.

Animals↗
PubMed1993

Delayed hemolytic transfusion reaction with anti-Jkb erythrocyte antibody after open heart surgery.

A patient suffering from delayed hemolytic transfusion reaction with anti-Jkb erythrocyte antibody after open heart surgery is reported on. On preoperation evaluation, a 42-year-old woman who had never been transfused exhibited a negative erythrocyte autoantibody. After the operation of aortic valve replacement and open mitral commisurotomy, she developed a severe hemolytic anemia with a positive rare anti-Jkb erythrocyte antibody on the 14th postoperative day. Precautions are discussed which need to be taken to distinguish delayed hemolytic transfusion reaction from mechanical hemolysis caused by extracorporeal circulation and prostheses.

Adult↗
PubMed1993

Association of Actinobacillus actinomycetemcomitans leukotoxin with nucleic acids on the bacterial cell surface.

Actinobacillus actinomycetemcomitans, a periodontopathic gram-negative bacterium, produces a leukotoxin that is a member of the RTX cytotoxin family. Although genes may function in toxin secretion, the leukotoxin is not secreted extracellularly but remains associated with the bacterial cell surface. We report here that this toxin-cell surface association is mediated by nucleic acids and directly demonstrate that the extracellular secretion of toxin occurs in growing cultures with increased ionic strength of medium. All examinations were performed with freshly harvested A. actinomycetemcomitans 301-b from anaerobic fructose-limited chemostat cultures. The occurrence of cell surface-localized DNA was shown by directly digesting whole cells with the restriction endonuclease EcoRI or HindIII, which yielded many DNA fragments. The cell surface DNA constituted about 20% of the total cellular DNA. The leukotoxin was released from the whole cells by digestion with DNase I as well as restriction endonucleases. Because the leukotoxin binds ionically to DNA, it is dependent on the ionic strength of buffers or media. Accordingly, the toxin was released from cells suspended in saline at pH 7.5 in the presence of increasing amounts of MgCl2 (0 to 10 mM) or NaCl (0 to 50 mM). Moreover, a considerable quantity of leukotoxin was detected in the culture supernatant of fructose-limited chemostat cultures when sodium succinate solution was pumped into the steady state as an additional salt (30 and then 50 mM). This toxin-DNA association was also found in well-characterized strains including not only the leukotoxin-producing ATCC 29522 but also the toxin production-variable ATCC 29523 and the non-leukotoxin-producing ATCC 33384 when these strains were grown in the chemostat culture.

Aggregatibacter actinomycetemcomitans↗
PubMed1993

Modulation of cardiac myocyte beating rate and hypertrophy by cardiac fibroblasts isolated from neonatal rat ventricle.

We evaluated the in vitro modulation of cardiac myocyte beating rate and growth hypertrophy in the presence or absence of cardiac fibroblasts. Cardiac myocytes and fibroblasts were isolated from neonatal rat ventricles, and cultures of either myocytes alone or of myocytes in co-culture with fibroblasts were established and observed for 21 days. The beating rate in control myocytes increased rapidly, reached peak values on day 5 (266.2 +/- 58.2 beat/min), and then decreased by day 21. The beating rate of myocytes which were co-cultured with fibroblasts in group 2-1 (2-1 ratio of myocytes to fibroblasts, 6.0 x 10(5) total cells/well) was significantly lower than that in control myocytes, and showed a decreased peak value on day 7 (135.1 +/- 46.4). The beating rate in group 1-1 was significantly less than that of group 2-1, with a peak value on day 7 (85.9 +/- 24.9). Group 1-2 myocytes did not show a beating rate increase. Myocyte hypertrophy was measured after three days of culture. The surface area of myocytes which had been co-cultured with fibroblasts was significantly increased, as compared to that of control myocytes. In addition, myocyte surface area increased with increasing numbers of fibroblasts (mean myocyte surface areas in group 2-1, 1-1 and 1-2 were 143 +/- 21, 163 +/- 33, 206 +/- 38% of control, respectively). In conclusion, suppression of the myocyte beating rate and acceleration of myocyte hypertrophy are characteristic expressions of myocyte differentiation and growth during the neonatal period The present results suggest that fibroblasts play an important role in controlling myocyte development.

Animals↗
PubMed1993

Asymptomatic syringomyelia associated with cerebellopontine angle meningioma--case report.

A 66-year-old female with a 3-year history of left trigeminal neuralgia presented with an unusual left cerebellopontine angle meningioma associated with asymptomatic syringomyelia at the C2 to C4 levels diagnosed by magnetic resonance (MR) imaging. Two months after total tumor removal, the syringomyelia had diminished without shunting. MR images are useful as a basis for early diagnosis of syringomyelia.

Aged↗
PubMed1993

[In vitro evaluation of prostaglandin I2 analogue on hypothermic injury to immature myocytes].

We evaluated the functional and biochemical effects of prostaglandin I2 analogue (PGI-A) on cardiac myocytes incubated under hypothermic conditions. Myocytes were isolated from neonatal rat ventricles and cultured for 4 days. Then, myocytes (12.5 x 10(5) myocytes/flask) were incubated at 4 degrees C for 24 hrs in media with PGI-A as follows; O M PGI-A (group C: control), 10(-9) M (group P1), 10(-8) M (group P2), 10(-7) M (group P3), 10(-6) M (group P4). After hypothermic incubation, CPK and LDH were measured. The myocytes were then cultured for 24 hrs at 37 degrees C to evaluate the recovery of myocyte beating rate. For the beating rate, group P2 showed significantly increased recovery compared to the control (P2: 47.9, p < 0.025, C:18.1 percent of control; ie, beating rate prior to hypothermic incubation). The release of CPK and LDH was significantly suppressed in group P2 compared to the control (P2:57.7, p < 0.05, 275.1, p < 0.025; C:96.8 mIU/flask, 439.6 mIU/flask, respectively). In conclusion, prostaglandin I2 has direct cytoprotective characteristics for immature myocytes that may be suitable for cardiac preservation.

Animals↗
PubMed1993

[Transvenous pacemaker implantation for sick sinus syndrome with mirror-image dextrocardia].

A case of sick sinus syndrome with mirror-image dextrocardia which was associated with bilateral superior vena cava and an absent inferior vena cava with azygos continuation is reported. A 45-year-old woman was referred to our hospital with the chief complaints of dizziness and palpitation. The electrocardiogram showed a atrial fibrillation with a 4-second period of asystole. A permanent endocardial bipolar demand pacemaker was inserted through the left superior vena cava. Since anomaly of venous system is commonly associated with mirror-image dextrocardia, the angiogram is necessary prior to permanent pacemaker implantation.

Dextrocardia↗
PubMed1993

[An adult case of secundum atrial septal defect with severe postoperative pulmonary hypertensive crisis].

We reported an adult case of secundum atrial septal defect with severe postoperative pulmonary hypertensive crisis. A 52 year-old female with secundum atrial septal defect and pulmonary hypertension underwent ASD patch closure. After the operation she experienced severe postoperative pulmonary hypertensive crisis. Only administration of PGE1 through the pulmonary artery was effective of hemodynamic improvement and reduction of pulmonary hypertension. Histological diagnosis of lung biopsy showed thromboembolism of small pulmonary artery. Pulmonary hypertension has not been evident during the 3 months since the cardiac catheterization was performed.

Alprostadil↗
PubMed1993

[Bilateral coronary-pulmonary artery fistulas with a large saccular aneurysm: a case of cardiac tamponade following rupture of the coronary artery aneurysm].

A case of bilateral coronary-pulmonary artery fistulas with a large saccular aneurysm is reported as follows. The patient was a 72-year-old woman who was referred to our hospital with a complaint of abnormal shadow on chest X-ray and had the past history of cardiac tamponade. The fistula was ligated and the aneurysm was resected with the extracorporeal circulation. Her Postoperative course was uneventful. Coronary arteriography showed that bilateral coronary-pulmonary artery fistulas had completely disappeared.

Aged↗
PubMed1993

Effect of Ca2+ on the binding of Actinobacillus actinomycetemcomitans leukotoxin and the cytotoxicity to promyelocytic leukemia HL-60 cells.

The effects of Ca2+ on the binding of Actinobacillus actinomycetemcomitans leukotoxin (LT) to LT-susceptible promyelocytic leukemia HL-60 cells and the consequent cytotoxicity were investigated in comparison with those on LT-resistant erythroleukemia K-562 cells. The total amount of LT bound to the HL-60 and K-562 cells, as determined by ELISA using anti-LT rabbit serum, was essentially the same for both cells. The percentage of bound LT decreased in the presence of phosphatidylcholine (PC) was also almost equal for both cells. In contrast, EGTA added in the presence of PC enhanced the decrease of bound LT significantly from HL-60, but not from K-562. By monitoring the fluorescence of Fura-2 and of fluorescein as a measure for the change in intracellular calcium ions ([Ca2+]i) and cytotoxic activity, respectively, we showed that the exposure of HL-60 to LT induced the [Ca2+]i increase followed by the cell death, whereas this was distinctly not the case for K-562. These results indicate that a Ca(2+)-dependent LT-binding mechanism is possibly the step characteristic to LT-susceptible HL-60 cells.

Aggregatibacter actinomycetemcomitans↗