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T Urano

Publications and source records attributed to T Urano.

At least 235 records · Page 13Linked to original sources
PubMed1991

Effects of N-terminal peptide of Glu-plasminogen on the activation of Glu-plasminogen and its conversion to Lys-plasminogen.

In order to analyze the mechanism of the intramolecular binding of the N-terminal peptide of Glu-plasminogen (Glu-plg) to its kringles, which results in its tight conformation, we synthesized peptides of the N-terminal portion of Glu-plg molecules and analyzed their effects on the activation of Glu-plg and its conversion to Lys-plasminogen (Lys-plg) by plasmin. Three peptides of Ala44-Lys50, Ala44-Glu51 and Ala44-Ser49 were synthesized in order to examine the effect of lysine residue in the peptide. Ala44-Lys50 and Ala44-Glu51 enhanced the activation of Glu-plg by urokinase, whereas the activation of Lys-plasminogen (Lys-plg) was slightly inhibited. The conversion of Glu-plg to Lys-plg by plasmin was also enhanced by these peptides. The results suggest that Ala44-Lys50 and Ala44-Glu51 worked on Glu-plg in a similar manner as lysine analogues by making its conformation looser. The third peptide Ala44-Ser49 did not have any effect on the activation of Glu-plg by urokinase or the conversion of Glu-plg to Lys-plg by plasmin. Ala44-Lys50 residue of Glu-plg is, therefore, strongly implicated as a candidate for the responsible site of the intramolecular binding in Glu-plg.

Alanine↗
PubMed1991

Alcohol-induced depression: involvement of serotonin.

We examined tryptophan and serotonin (5-hydroxytryptamine) levels in the blood after consumption of alcohol. Forty-five minutes after drinking, whole blood serotonin concentration was significantly reduced, whereas no changes were observed in tryptophan level. The diurnal rhythm of 5-HT in subjects who the day before had drunk alcohol was quite different from the control group, but very similar to that of patients with depression. The results strongly suggest that the mechanism of depression after alcohol drinking may be related to serotonin.

Adult↗
PubMed1991

Distinguishing pancreatic carcinoma from other periampullary carcinomas by analysis of mutations in the Kirsten-ras oncogene.

The prevalence of Kirsten (Ki)-ras gene mutations was studied in 105 paraffin-embedded tissues obtained from 40 patients with pancreatic cancer, 48 with bile duct carcinoma (19 distal, 6 middle, and 23 proximal), 16 with ampullary carcinoma and 1 with duodenal cancer, by in vitro amplification of target sequences by the polymerase chain reaction (PCR). With regard to pancreatic cancers, the authors' data confirm the very high frequency (88.6%) of Ki-ras gene mutations occurring at codon 12. Five pancreatic carcinomas did not contain the Ki-ras mutation and included rare types of histopathology. By histologic review after the examination of Ki-ras mutations through PCR, the diagnosis of four patients could be legitimately revised from other periampullary carcinoma to pancreatic carcinoma. In the ampullary carcinoma, the prevalence of mutations in Ki-ras codon 12 was 13.3%. Although there was a large difference in incidence of mutations between distal and middle or proximal bile duct carcinoma, the prevalence of mutations in bile duct carcinoma was limited to 19.6%. Unlike other approaches to diagnose periampullary carcinoma, detection of a mutation in Ki-ras codon 12 by PCR may distinguish pancreatic carcinoma from other periampullary carcinomas that have better prognoses.

Aged↗
PubMed1991

Bacterial translocation from the gastrointestinal tract in various mouse models for human diabetes.

Bacterial translocation from the gastrointestinal (GI) tract to other internal organs was examined in multiple low-dose streptozotocin-injected (M-STZ), single large-dose streptozotocin-injected (S-STZ), alloxan-injected (Alloxan), and non-obese diabetic (NOD) mice. The incidence of bacterial translocation from the GI tract to the tested organs among diabetic mice was in the order of M-STZ mice greater than S-STZ mice greater than NOD, Alloxan, and control mice. The injections of insulin to M-STZ mice did not decrease the incidence of translocation. These results suggest that bacterial translocation from the GI tract in diabetic mice is not induced by diabetes.

Animals↗
PubMed1991

The advantage of enzyme-linked immunosorbent assay (ELISA) as a method of microbiological monitoring for rat virus (RV).

An enzyme-linked immunosorbent assay (ELISA) was tested to detect antibodies against rat virus (RV). The purified ELISA antigens were prepared from rat embryonic cells infected with RV-13 (prototype strain) and UT-2 (Japanese isolate), respectively. Western blotting analysis confirmed that both of these antigens had three structural polypeptides (81 K, 61 K, and 59 K). Eleven laboratory and wild rat colonies in Japan were tested for rat virus contamination, serologically. No significant differences in the sero-positive ratio and the distributions of ELISA titers were demonstrated in the ELISA, using antigens from RV-13 and UT-2. ELISA was more sensitive and specific for detecting antibodies against RV from rat serum rather than hemagglutination inhibition (HI) test. This study also confirmed that the RV contaminated widely in colonies of laboratory and wild rats in Japan, and suggested that RV would have to be checked during the microbiological monitoring of laboratory rats.

Animals↗
PubMed1991

Mutations in the Kirsten-ras oncogene are common but lack correlation with prognosis and tumor stage in human pancreatic carcinoma.

Utilizing the polymerase chain reaction (PCR), we studied the presence and pattern of mutations in the Kirsten (Ki)-ras oncogene, using paraffin-embedded sections of pancreatic carcinoma tissue from 53 patients. Mutations in the Ki-ras oncogene were evident in 46 of the 53 patients (87%) in codon 12. The predominant mutation was from glycine (GGT) to aspartic acid (GAT). Among the 46, one had an additional mutation in Ki-ras codon 13, and no mutation was found in codon 61. These oncogenetic mutations were observed even in early stage pancreatic carcinoma, and there was no statistically significant difference in the rate or positivity of mutations among the stages of the disease. With regard to patient survival, statistical analysis comparing 37 patients with mutations in the Ki-ras oncogene and four patients without mutations revealed no significant difference. These results suggest that mutations in the Ki-ras oncogene may be related to the initiation of carcinogenesis, but are not linked to malignant potential or promotion of human pancreatic cancer.

Adenocarcinoma↗
PubMed1990

Fluctuation of tPA and PAI-1 antigen levels in plasma: difference of their fluctuation patterns between male and female.

The circadian fluctuation of the fibrinolytic activity and the antigen levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI-1) in plasma were analyzed in normal male and female volunteers. Samples were obtained at 8:30, 10:30, 12:30, 14:30 and 16:30 h. Euglobulin clot lysis time (ECLT) showed the longest time at 8:30 to 10:30 h and the shortest time at 16:30 h. The highest level of tPA was obtained at 8:30 h and the lowest at 14:30 h in men, whereas the highest value was at 8:30 h and the lowest was at 16:30 h in females. Free PAI-1 showed highest value at 10:30 h in men and at 8:30 h in women. The lowest values obtained at 16:30 h in both men and women and were about one third of the highest values. ECLT was always shorter in females than in males and parameter such as tPA and PAI-1 were also lower in females than in males. The phase of the circadian rhythm of the fibrinolytic parameters may be advanced in females than in males.

Adolescent↗
PubMed1990

Fluctuation of TPA and PAI-1 antigen levels in plasma: difference of their fluctuation patterns between male and female.

The daytime fluctuation of the fibrinolytic activity and the antigen levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI-1) in plasma were analyzed in normal male and female volunteers. Samples were obtained at 8:30, 10:30, 12:30, 14:30 and 16:30 h. Euglobulin clot lysis time (ECLT) showed the longest time at 8:30 to 10:30 h and the shortest time at 16:30 h. The highest level of tPA was obtained at 8:30 h and the lowest at 14:30 h in men, whereas the highest value was at 8:30 h and the lowest was at 16:30 h in females. Active free PAI-1 showed highest value at 10:30 h in men and at 8:30 h in women. The lowest values obtained at 16:30 h in both men and women and were about one third of the highest values. ECLT was always shorter in females than in males and parameter such as tPA and PAI-1 were also lower in females than in males. The phase of the circadian rhythm of the fibrinolytic parameters may be advanced in females than in males.

Adolescent↗
PubMed1990

Relationships between euglobulin clot lysis time and the plasma levels of tissue plasminogen activator and plasminogen activator inhibitor 1.

The relationships between tissue plasminogen activator (tPA), its fast acting inhibitor (PAI-1) and euglobulin clot lysis time (ELT) were investigated with healthy volunteers' plasma. Turbidimetric clot lysis assay by the microtiter plate reader was utilized for ELT with a slight modification. Both tPA and PAI-1 showed the significant correlation with ELT. tPA had a significantly positive, not negative, correlation with ELT (R = 0.387, p less than 0.001). Higher correlation coefficients (R = 0.580, p less than 0.001 and R = 0.599, p less than 0.001) were obtained between ELT and total PAI-1 or free PAI-1 than tPA or tPA-PAI-1 complex (R = 0.427, p less than 0.001). The positive correlation was also obtained between tPA and PAI-1. These data suggest that PAI-1 is a highly important factor for ELT, especially, the amounts of free PAI-1 being the key factor to determine the ELT, which can represent the potential activity of the fibrinolytic system.

Adult↗
PubMed1990

Significance of urinary complement components in various glomerular diseases.

The concentrations of two components of the complement system (C1q and C3) were measured in the urine and blood in 10 normal subjects and 134 patients with primary and secondary glomerulonephritis by using a highly sensitive enzyme immunoassay. The values of urinary excretion of C1q and C3 were well correlated to the ratios of fractional clearance of these complement proteins to that of neutral dextran of 55 A, which was used to minimize the influences of glomerular sieving because of their comparable molecular size to these complement components. The rate of renal tubular reabsorption of C1q and C3 were at least 89.2 and 93.4% of filtrated C1q and C3, respectively. Urinary C1q and C3 were excreted significantly in cases of membranoproliferative glomerulonephritis (MPGN), membranous glomerulonephritis, IgA nephropathy with both mesangial and capillary immune complex (IC) deposit and also in case of active lupus nephritis. On the other hand, the concentrations of these complement components were low in case of minimal lesion nephrotic syndrome, mild proliferative glomerulonephritis, inactive lupus nephritis and diabetic nephropathy without any immune staining. There was a significant correlation between the urinary excretion of C1q or C3 and intraglomerular IC deposition, especially IC deposition along the glomerular capillary wall. However, the degree of the excretion of these proteins was not correlated to the degree or permselectivity of proteinuria. The correlations between urinary C1q and C3 were observed in cases of IgA nephropathy with both mesangial and capillary deposit and MPGN, although we couldn't see the correlation in the other glomerular diseases. It is suggested that urinary excretion of such complement components represents the fixation of complement by deposited intraglomerular IC. The measurement of urinary concentration of these complement components provides a new clue to investigation or diagnosis of glomerular diseases.

Arginine↗
PubMed1990

Fluctuations of euglobulin lysis time, tissue plasminogen activator, and free and total plasminogen activator inhibitor levels in plasma in daytime.

Blood was taken from healthy 15 males and 10 females at 9:30 h, 10:00 h and 12:30 h. The euglobulin fraction was prepared and clotted by the addition of human thrombin. The clot lysis time shortened significantly from 9:30 h to 10:00 h (p less than 0.01) and further to 12:30 h (p less than 0.01). Plasma levels of tissue plasminogen activator (t-PA) antigens did not change from 9:30 h to 10:00 h, but slightly and significantly to 12:30 h (p less than 0.01). Plasma levels of free plasminogen activator inhibitor-1 (PAI-1) and complex of t-PA-PAI-1 decreased from 9:30 h to 10:00 h (p less than 0.02) and to 12:30 h (p less than 0.01). Plasma levels of total PAI-1 (free plus complex) decreased from 9:30 h to 10:00 h (p less than 0.01) and to 12:30 h (p less than 0.01). These results suggest that a major factor contributing to the enhanced fibrinolytic activity of the euglobulin fraction may be a level of PAI-1 (free and total).

Adult↗
PubMed1990

A new combined trivalent live measles (AIK-C strain), mumps (Hoshino strain), and rubella (Takahashi strain) vaccine. Findings in clinical and laboratory studies.

Trivalent virus vaccine, containing measles AIK-C strain, mumps Hoshino strain, and rubella Takahashi strain, was administered to a total of 1369 healthy children, 8 months to 18 years of age. For comparative study, monovalent vaccines of AIK-C strain and Hoshino strain were administered to 147 and 122 initially seronegative children, respectively. The clinical and serological responses following vaccination were analyzed. Among the recipients of the trivalent vaccine, 893 were initially seronegative to all three viruses. Inoculation induced sufficient serological responses: 99.7% for measles and rubella viruses and 96.3% for mumps virus. The incidence of febrile reaction (greater than or equal to 37.5 degrees C axillary temperature) was low, 15.9%, and a temperature of 39.0 degrees C or higher occurred in only 1.3% of the subjects. The seroconversion rate, magnitude of antibody titers, and incidence of clinical reactions following the trivalent vaccination were similar to those occurring after the monovalent measles vaccination.

Adolescent↗
PubMed1990

Absorption of methylmercury compounds from rat intestine.

Intestinal absorption of methylmercury complexed with non-protein sulfhydryl compounds (NPSHs) as occurs in bile was studied by means of direct injection of mercury compounds into ligated intestinal segments of rats. The extent of absorption of methylmercury-cysteinylglycine (MM-CysGly) was similar to that of methylmercury-cysteine (MM-Cys) and 1.5 times larger than that of methylmercury-glutathione (MM-GSH). This results suggested that MM-CysGly, which is recognized as a major component of methylmercury in rat bile, can be easily reabsorbed from the intestine. These results indicate that not only MM-GSH and MM-Cys but also MM-CysGly may play important roles in the intestinal reabsorption of methylmercury during its enterohepatic circulation. When the ligated intestine was pretreated with probenecid and acivicin, the intestinal absorption of MM-GSH was depressed much more than in the case of treatment with acivicin alone. This indicates the possibility that there are at least two systems for intestinal transport of MM-GSH, i.e. gamma-glutamyltranspeptidase (GGT)-dependent and -independent systems.

Animals↗