Search PubMed⌕ Search

Biomedical subjects

H Yano

Publications and source records attributed to H Yano.

At least 343 records · Page 19Linked to original sources
PubMed1992

Establishment and characterization of a new human extrahepatic bile duct carcinoma cell line (KMBC).

A new human extrahepatic bile duct carcinoma cell line (KMBC) was established from a serially transplanted tumor in nude mice that originated from a surgically resected tumor from a 73-year-old Japanese man; the cell line has been maintained for 5 five years. KMBC cells proliferate in a monolayered sheet with a population doubling time of 30 hours. Chromosome number was distributed in a range from 37 to 44, with modal numbers of 40 and 41. KMBC cells and the reconstituted tumor in a nude mouse showed moderately to poorly differentiated adenocarcinoma and possessed various functional characteristics of extrahepatic bile duct carcinoma. KMBC cells secreted carbohydrate antigen 19-9, tissue polypeptide antigen, carcinoembryonic antigen, ferritin, beta 2-microglobulin, fibronectin, and alpha 2-macroglobulin and produced glutamic oxaloacetic transaminase and alkaline phosphatase. KMBC is the second established cell line that originated from a human extrahepatic bile duct carcinoma in the world literature, and it will be applicable to various experiments.

Adenoma, Bile Duct↗
PubMed1992

The c-kit receptor ligand functions as a mast cell chemoattractant.

Mast cells accumulate at sites of neovascularization, solid tumors, and many immune reactions. Such accumulation requires directed migration of mature mast cells or their precursors. The nature of the chemoattractants that regulate mast cell motility and the identity of the receptors that mediate the chemotactic response are poorly understood. We have tested the ability of stem cell factor (SCF), a mast cell growth factor, to stimulate mast cell migration. Our results show that SCF is a potent mast cell attractant that stimulates directional motility of both mucosal and connective tissue-type mast cells. The activity is potentiated by costimulation with interleukin-3 (IL-3), another mast cell chemoattractant. SCF, a known ligand for the c-kit tyrosine kinase receptor, was unable to stimulate motility in W42 mutant mast cells, which have a defective c-kit tyrosine kinase. However, W42 mast cells were still able to migrate in response to IL-3. These results show that SCF is a chemotactic factor as well as a growth factor and that the c-kit receptor can transduce signals leading to both cell proliferation and increased directional cell motility.

Animals↗
PubMed1992

Effect of the beta-adrenoceptor antagonist, propranolol, on feeding induced by noradrenaline and muscimol in rats kept at high and temperate-ambient temperatures.

Both the gamma-aminobutyric acid (GABA) receptor agonist, muscimol, and noradrenaline stimulated the feeding behavior of rats in the two environments. When noradrenaline or muscimol was administered, however, the food intake at 26 degrees C was greater than that at 33 degrees C. In addition, the stimulatory effect of noradrenaline on food intake was significantly depressed by propranolol pretreatment at both temperatures. The stimulatory effect of muscimol on food intake was significantly depressed by the propranolol pretreatment at 33 degrees C but not at 26 degrees C. Some eating-stimulatory subsystems associated with feeding behavior induced by noradrenaline or muscimol might have been depressed in the hot environment, thus the food intake increased by these drugs in rats acclimated to the hot environment was less than that in rats acclimated to the temperate environment.

Animals↗
PubMed1992

A new human cholangiocellular carcinoma cell line (KMC-1).

We have recently established a cholangiocellular carcinoma (CCC) cell line, designated KMC-1, from a nude mouse subcutaneous tumor which developed after inoculation of a surgically resected peripheral type CCC from a 62-year-old Japanese male patient. KMC-1 cells grew over a 26-month period and passaged 57 times. These cells retained the morphologic characteristics of both the original tumor and the subcutaneous tumor in the nude mouse, which mainly consisted of irregular tubules and invaded surrounding interstitial tissue in part with an indurate pattern. KMC-1 cells grew in a monolayer pavement-like cell arrangement with tubular formation in part. Some cells and/or glands had a mucin-like substance inside. The doubling time of KMC-1 cells growing in serum-containing medium was 54 h at passage 31. Cell growth in serum-free medium was slow but steady. The number of chromosomes was distributed in range from 73 to 83 with modes of 76 and 78. KMC-1 cells secreted some tumor markers such as DUPAN-2, CA125, TPA, hCG, CA19-9 and ferritin, however, the secretion of DUPAN-2, and CA19-9 and ferritin were only detectable in serum-containing and serum-free medium, respectively. These findings suggest that KMC-1 cells will provide a variety of experimental models for research on CCC and the mechanisms of tumor marker secretion.

Adenoma, Bile Duct↗
PubMed1992

Differential scanning calorimetric studies on bovine serum albumin: III. Effect of sodium dodecyl sulphate.

Measurements of differential scanning calorimetry (d.s.c.) have been made on the complex bovine serum albumin (BSA)--sodium dodecyl sulphate (SDS) under various conditions. There are two peaks P1 and P2 in the d.s.c. curve for BSA at pH 7 and in the absence of NaCl, indicating the presence of the heat-induced transition of BSA. There are three peaks P1, P2 and P3 in the curve for the system with the molar mixing ratio SDS/BSA = 1. With the increase in the amount of SDS, the peak P3 grows at the expense of P1 and P2. There is only a single peak P3 in the curve for the systems SDS/BSA > 7, and no peak at SDS/BSA = 50 and 100. There is a single peak P12 in the curve for BSA at pH 7 and in the presence of 0.05 M NaCl, indicating that the heat-induced transition is suppressed. There are two peaks P12 and P3 for the systems SDS/BSA = 1-5; the area ratio of the peak P3 to P12 increases with the increase in the amount of SDS. There is only a single peak P3 when SDS/BSA > 7, and no peak at SDS/BSA = 50. It is concluded that the peak P3 is a product of SDS regardless of the presence or absence of NaCl. Values of thermal denaturation temperature (Td) and enthalpy (delta H) of thermal denaturation indicate that the complex AD12 (A = BSA, D = SDS) is in the most thermostabilized state.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

A novel point mutation in the human insulin gene giving rise to hyperproinsulinemia (proinsulin Kyoto).

We have identified a 65-yr-old nonobese Japanese man with diabetes mellitus, fasting hyperinsulinemia (150-300 pM), and a reduced fasting C-peptide/insulin molar ratio of 2.5-3.0. Fasting hyperinsulinemia was also found in his son and daughter. Analysis of insulin isolated from the serum of the proband and his son by reverse-phase high performance liquid chromatography revealed a minor peak coeluting with human insulin and a major peak of proinsulin-like materials. The insulin gene of the patient was amplified by the polymerase chain reaction and the products were sequenced. A novel point mutation was identified in which guanine was replaced by thymine. The substitution gives rise to a new HindIII recognition site and results in the amino acid replacement of leucine for arginine at position 65. These results indicate that the amino-acid replacement prevents recognition of the C-peptide-A chain dibasic protease and results in an elevation of proinsulin-like materials in the circulation. Furthermore, in this family the proinsulin-like materials is due to a biosynthetic defect, inherited as an autosomal dominant trait. Rapid detection of this mutation can be accomplished by HindIII restriction enzyme mapping of polymerase chain reaction-generated DNA, which enables us to facilitate the diagnosis and screening.

Adult↗
PubMed1992

Characterization of D-aminoacylase from Alcaligenes denitrificans DA181.

The D-aminoacylase produced by Alcaligenes denitrificans DA181 was a new type of aminoacylase which had both high stereospecificity and specific activity. The molecular weight and isoelectric point of this enzyme were 58,000 and 4.4, respectively. The apparent Km and kcat values of this enzyme for N-acetyl-D-methionine were estimated to be 0.48 mM and 6.24 x 10(4) min-1, respectively. The optimum temperature was 45 degrees C. The enzyme was stable up to 55 degrees C for 1 hr in the presence of 0.2 mg/ml bovine serum albumin. The enzyme was stable in the pH range of 6.0 to 11.0 with an optimum pH of 7.5. This enzyme contained about 2.1 g atom of zinc per mole of enzyme. Enzyme activity was inhibited by incubation with EDTA. The inhibition by EDTA was fully reversed by Co2+ and partially by Zn2+.

Alcaligenes↗
PubMed1992

Chronic subdural hematoma following bypass surgery--report of three cases.

Bypass surgery is a safe procedure with low mortality and morbidity, and few reported surgical complications. Three patients developed postoperative chronic subdural hematoma (CSDH): two with stroke after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and one with moyamoya disease after STA-MCA anastomosis combined with encephalomyosynangiosis. The factors inducing CSDH after revascularization in the seven reported and present cases included postoperative subdural effusion associated with brain atrophy, and postoperative anticoagulant therapy such as aspirin. CSDH may occur in patients with pre-existing brain atrophy and postoperative subdural effusion. Anticoagulant therapy should be avoided at the early postoperative stage after bypass surgery.

Brain↗
PubMed1992

Expression of GLUT1 and GLUT2 glucose transporter isoforms in rat islets of Langerhans and their regulation by glucose.

Previous studies revealed that rat islets express the GLUT2-liver facilitative glucose transporter isoform, a glucose carrier with a low affinity for glucose but a high capacity for glucose transport. These studies indicated the presence of a second glucose transporter in rat islets; however, they did not indicate to which of the five known facilitative glucose transporters it corresponded. In this study, we isolated RNA from rat islets of Langerhans and confirmed the presence of GLUT2 mRNA. In addition, we present data indicating that the second isoform expressed in islets is the GLUT1-erythrocyte isoform. The effect of culturing islets in 5.5, 8.3, or 11.1 mM glucose on the levels of GLUT1 and GLUT2 mRNA also was examined. The levels of GLUT1 and GLUT2 mRNA were two- and threefold higher, respectively, in islets cultured for 24 h in 11.1 mM glucose compared with those incubated in the presence of 5.5 mM glucose. Therefore, the previously observed increase in GLUT2 mRNA levels in the islets of rats made hyperglycemic by chronic infusion of glucose can be mimicked in vitro, implying that glucose regulates GLUT2 mRNA expression.

Animals↗
PubMed1992

Glucose as regulator of glucose transport activity and glucose-transporter mRNA in hamster beta-cell line.

To investigate the role of glucose in regulating glucose transporters in pancreatic beta-cells, we studied the hamster clonal beta-cell line HIT-T15, which retains responsiveness to glucose. Northern blot analysis demonstrates that GLUT2 and GLUT1 mRNA are abundant in HIT cells. After a 24-h culture with various concentrations of glucose (0-22.2 mM [0-400 mg/dl]), the GLUT2 mRNA level in HIT cells increased by 40% at 22.2 mM (400 mg/dl) glucose compared with 11.1 mM (200 mg/dl) without a change in mRNA stability. It also decreased proportionally to the reduction of glucose concentration. Glucose deprivation resulted in a decrease of GLUT2 mRNA to an almost undetectable level, with a marked increase in the degradation rate of mRNA. In contrast, the GLUT1 mRNA was not affected by glucose. We show that glucose uptake is highest in HIT cells incubated at 2.8-5.5 mM (50-99 mg/dl) glucose for 24 h, and that levels in cells cultured at 0 mM (0 mg/dl) and 22.2 mM (400 mg/dl) glucose decrease to approximately 20% of the maximum level. This decrease is consistent with the effects of glucose on glucose-stimulated insulin secretion in HIT cells. Our results indicate that glucose is involved in regulating GLUT2 mRNA and glucose uptake activity and that the glucose responsiveness of the insulin secretion correlates with the glucose-induced change in glucose uptake activity in HIT cells.

Animals↗
PubMed1992

The influence of dietary medium and long chain triglycerides on growth performances and fat deposition in growing rats.

The present study was undertaken to investigate the effects of dietary medium and long chain triglycerides (MCT and LCT) on fat deposition and fatty acid composition of adipose tissues of rats. Twenty-seven Wistar strain male rats were divided into three groups and fed semisynthetic experimental diets: Basal (AIN 76), MCT (basal+C8:0 10%), LCT (basal+corn oil 10%). Feed intake was measured every day and body weight was measured once a week. At the beginning, 4th and 8th week of experimental feeding, 3, 12, 12 rats were slaughtered, respectively. Liver, perirenal and epididymal adipose tissue pads were weighted and their fatty acid composition was determined. Chemical composition of wholebody carcass was measured. Body weight gain was greater in rats fed the LCT diet than in rats fed the basal and MCT diets. Feed intakes were decreased in rats fed the MCT and LCT diets compared to that of the basal group. Subsequently, when compared to the basal group rats, feed efficiencies in rats fed the MCT and LCT diets were improved at the level of 6 and 14% for 4 weeks, and then 17 and 24% for 8 weeks, respectively. The weight of perirenal and epididymal adipose tissue pads tended to be larger in rats fed the MCT and LCT diets than in the basal group, although not significant. There were not significant differences in wholebody composition among the three groups. But it appeared that in rats fed the MCT diet, moisture content tended to be decreased and crude protein content increased compared to the LCT group rats. Fatty acid composition of the rats fed the LCT diet showed a good reflection of dietary fatty acid composition. Unlike LCT, little of medium chain fatty acid (MCFA) itself were incorporated into liver or adipose tissues. However, it seems that fat deposition of the MCT group was accomplished not by incorporation of dietary fatty acids but by de novo fatty acids synthesis.

Adipose Tissue↗
PubMed1992

[A case of small liver cancer presenting as a huge mediastinal mass].

A 61-year-old male was admitted because of hemoptysis. He had a 9 year history of liver cirrhosis associated with HB viral chronic hepatitis. Physical examination revealed no abnormalities. Laboratory investigations revealed positive HBs antigen with normal alpha-fetoprotein. Chest X-ray film showed large mediastinal lymph nodes and an endobronchial polypoid mass in the distal end of the right main bronchus. The right main PA was narrowed due to compression by the mediastinal mass. Bronchoscopic examination revealed a polypoid mass in the right main bronchus. The biopsy specimen was histologically diagnosed as undifferentiated large cell carcinoma. The patient developed respiratory failure, and died 3 weeks after admission. Autopsy revealed a small liver cancer of 1.3 cm diameter within the cirrhotic liver, associated with a small abdominal lymph node metastasis and large mediastinal lymph node swellings. Thromboembolism in the bilateral main pulmonary arteries was concluded to be the cause of death. The mediastinal mass which directly invaded into the right main bronchus had a close histological similarity with the liver cancer, showing undifferentiated carcinoma cells with bizarre nuclei and abundant cytoplasm. An immunohistological study revealed cells positive for alpha-fetoprotein in the mediastinal lymph nodes. The patient was diagnosed as having small liver cancer with mediastinal lymph node metastases. A survey of the literature revealed only a few cases of advanced hepatoma associated with prominent mediastinal metastases. This is the first reported case of small liver cancer presenting with large mediastinal lymph node metastases.

Carcinoma↗
PubMed1991

Liver and muscle-fat type glucose transporter gene expression in obese and diabetic rats.

In order to investigate the regulation of glucose transporter gene expression in the altered metabolic conditions of obesity and diabetes, we have measured mRNA levels encoding GLUT2 in the liver and GLUT4 in the gastrocnemius muscle from various insulin resistant animal models, including Zucker fatty, Wistar fatty, and streptozocin(STZ)-treated diabetic rats. Northern blot analysis revealed that GLUT2 mRNA levels were significantly (P less than 0.001) elevated in 14 wk Zucker fatty and Wistar fatty rats relative to lean littermates but were similar in these two groups at 5 wk of age. Furthermore, there was significant increase (P less than 0.01) in GLUT2 mRNA levels in STZ diabetic rats at 3 wk after treatment. GLUT4 mRNA levels were not significantly different between control and insulin resistant rats in all animal models. These results indicate that neither hyperinsulinemia nor hyperglycemia affects GLUT4 mRNA levels in the muscle. However, GLUT2 mRNA levels in the liver were elevated in obesity and diabetes, although this regulatory event occurred independently from circulating insulin or glucose concentrations.

Animals↗
PubMed1991

Tissue distribution and species difference of the brain type glucose transporter (GLUT3).

The complementary DNA for the human brain type glucose transporter (GLUT3) was used to determine its tissue specific expression in human, monkey, rabbit, rat, and mouse. Under high stringent conditions, 4.1 and 3.2 kilobase (kb) GLUT3 transcripts in monkey and a single 4.1 kb GLUT3 mRNA in rabbit, rat, and mouse were detected by RNA blot analysis. Although the GLUT3 transcripts were widely distributed, as are the erythrocyte type glucose transporter (GLUT1) transcripts, this mRNA is most abundant in the brain. However, the relative abundance of GLUT3 mRNA in the various regions of the monkey brain shows a different pattern from that of GLUT1 mRNA: GLUT3 is most highly expressed in the frontal lobe of the cerebrum, whereas GLUT1 is most abundant in the basal ganglia and the thalamus. Moderately higher GLUT3 mRNA levels were detected in the parietal lobe of the cerebrum, hippocampus, and cerebellum than the levels of GLUT1 transcripts. We also detected GLUT3 mRNA in adult human psoas major muscle, although it has been reported that the GLUT3 gene is scarcely expressed in adult human skeletal muscle of the thigh. In addition, in the rat and the mouse, no transcripts of the GLUT3 gene were detected in liver, kidney, small intestine, skeletal muscle, or fat besides in brain. Thus, the expression of the GLUT3 gene seems to be restricted to the brain in rodents. These results suggest that the expression of GLUT1 and GLUT3 genes might be regulated by different mechanisms.

Animals↗
PubMed1991

Immunohistologic detection of the epidermal growth factor receptor in human esophageal squamous cell carcinoma.

Epidermal growth factor receptor (EGF-R) expression was studied immunohistologically in 38 patients with esophageal squamous cell carcinoma. The EGF-R was faintly expressed in basal and parabasal layers of normal esophageal epithelia and in cancer nests of 20 patients; it was strongly expressed in all areas of dysplastic epithelia and in cancer nests of 18 patients. The patients with strongly expressed EGF-R had lymph node metastases more frequently, and their prognosis was poorer than those with faintly expressed EGF-R. The EGF-R expression showed a mosaic pattern in 17 patients and a diffuse pattern in 21 patients. The patients with a mosaic pattern had lymph node metastases more frequently and a worse prognosis than those with a diffuse pattern. Expression of EGF-R in metastatic lymph nodes was similar to that in strongly expressing areas of primary cancers with a mosaic pattern. Thus EGF-R expression may be an important indicator for malignancies of esophageal squamous cell carcinomas because primary cancer cells with strongly expressed EGF-R metastasize to lymph nodes more frequently.

Adult↗
PubMed1991

Negative U wave during percutaneous transluminal coronary angioplasty.

To clarify the clinical significance of the negative U wave during acute myocardial ischemia, the appearance of the U wave and ST-segment elevation on electrocardiography during percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending artery (LAD group: 11 patients) or right coronary artery (RCA group: 18 patients) was studied. During PTCA, U-wave inversion (newly developed negative U wave, and increased negativity of the pre-existing negative U wave) was observed in 37 (90%) of 41 patients in the LAD group and in 16 (89%) of 18 patients in the RCA group. The incidence of ST-segment elevation was similar to that of U-wave inversion; however, U-wave inversion appeared before detectable ST-segment elevation in 20 patients (49%) in the LAD group and in 4 patients (22%) in the RCA group. Moreover, U-wave inversion was observed frequently in a wider range of leads than ST-segment elevation. These results suggest that the U wave is a more sensitive indicator of myocardial ischemia than ST-segment elevation in some patients, and that a negative U wave may be produced by a different mechanism than that which produces ST-segment deviation, although both are related to myocardial ischemia.

Angioplasty, Balloon, Coronary↗