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Biomedical subjects

A Takada

Publications and source records attributed to A Takada.

At least 307 records · Page 17Linked to original sources
PubMed1991

Accumulation of glycoprotein in the Golgi apparatus of hepatocytes in alcoholic liver injuries.

To clarify the role of the hepatocytic Golgi apparatus in the accumulation of proteins in the hepatocytes of alcoholic liver disease, changes in the Golgi apparatus in human and experimental alcoholic liver injuries were analyzed. Immunoelectron microscopically, transferrin, one of the secretory glycoproteins from the liver, was retained in the smooth endoplasmic reticulum and Golgi apparatus of the hepatocytes in both human and rat alcoholic liver injuries. Biochemically, transferrin content in the Golgi fraction was clearly high in the rats with alcoholic liver injury. Desialo-glycoproteins were found in the serum of rats with alcoholic liver injuries. These results suggested that the glycosylation and secretion of hepatic glycoproteins in the Golgi apparatus were impaired in alcoholic liver injury. These abnormalities in the Golgi apparatus function may be important for the development of alcoholic liver injury.

Analysis of Variance↗
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

There are two major types of hepatitis C virus in Japan.

The polymerase chain reaction (PCR) was used to detect hepatitis C virus (HCV) in plasma from chronic non-A, non-B hepatitis patients. By choice of adequate primers, 19 of 24 samples (79%) were found positive. Sequence analysis of amplified 400 bp cDNA fragments encoding a portion of NS5 gene suggested that HCV can be classified into two types (named K1 and K2) in Japan. Slot blot hybridization of the fragments indicated that 13 were HCV-K1 and 6 were HCV-K2, which show 80% and 67% nucleotide sequence homology, respectively, with that of the prototype.

Amino Acid Sequence↗
PubMed1990

High idiotypic connectivity of the VH7183-encoded antibodies directed to a murine embryonic carbohydrate antigen, Lewis Y, as ascertained by syngenic anti-idiotype monoclonal antibodies.

The Lewis Y Ag is a carbohydrate Ag which is closely related to a well-known murine embryonic Ag, the stage-specific embryonic Ag-1 (SSEA-1), in its biochemical structure. It is expressed at the surface of murine embryonic cells as well as many murine cancer cells. For the analysis of idiotopes carried by the anti-Lewis Y antibodies, we generated two syngenic anti-idiotypic mAb, Id-A1 and Id-B4 (both BALB/c IgG1), which are directed to the idiotypic determinants carried by the anti-Lewis Y mAb, AH-6 (BALB/c IgM). Both Id-A1 and Id-B4 (Ab2) recognized paratope-related idiotopes carried by the AH-6 antibody (Ab1); they specifically inhibited the binding of AH-6 to the Lewis Y Ag. The high idiotypic connectivity of anti-Lewis Y antibodies was noted; the polyclonal anti-idiotype antibody, produced in the sera of BALB/c mice by immunizing AH-6 antibody, cross-reacted with several anti-Lewis Y mAb which has been established in different laboratories. Id-B4 and Id-A1 seem to represent such cross-reactive anti-idiotypic antibodies. Id-A1 recognized an idiotope carried by two out of six panel Ab1 mAb directed to the Lewis Y Ag. Id-B4 reacted with four out of the six panel antibodies, and was considered to recognize a recurrent idiotope of anti-Lewis Y antibodies which occurs more commonly than the idiotope recognized by Id-A1. All of the anti-Lewis Y antibodies which carry idiotopes that react with Id-A1 or Id-B4 were encoded by the VH genes of the VH7183 family; the most D-J proximal VH gene family in BALB/c mice, which is known to be preferentially expressed in embryonic B cells. Immunization of BALB/c mice with keyhole limpet hemocyanin-conjugated Id-B4 and/or Id-A1 induced a significant titer of anti-Lewis Y antibodies (Ab1-like Ab3) in the sera.

Animals↗
PubMed1990

Northern hybridization analysis of VH gene expression in murine monoclonal antibodies directed to cancer-associated ganglioside antigens having various sialic acid linkages.

The expression of the VH genes in 46 murine hybridoma cells that secrete mAb directed to the cancer-associated carbohydrate Ag, especially acidic glycolipids such as gangliosides and sulfated glycoplipids, was analyzed by Northern hybridization of poly(A)+ RNA of hybridoma with cDNA probes for nine VH gene families. Different hybridomas tended to express VH genes of the same family when the cognate Ag had the same or similar carbohydrate structures; i.e., the VH genes of the J558 family (group 1) were preferentially expressed in the mAb directed to various gangliosides that have NeuAc alpha (or NeuGc alpha) 2-3 and/or 2-8 linkage (71%), the most common linkage of sialic acid residues in the gangliosides of higher animals, and the hybridomas directed to sulfated glycolipids also expressed mainly the VH genes of the J558 family (80%). In contrast, the five mAb directed to various gangliosides with NeuAc alpha 2-6 linkage were exclusively encoded by the VH genes of Q52 family (group 2, 100%), and three antibodies directed to gangliosides with a NeuAc alpha 2-9 linkage all expressed genes of J606 family (group 6, 100%). The VH family usage was largely correlated with the linkage of sialic acid residues in the cognate carbohydrate Ag, but was not correlated at all with the difference in the fine specificities toward the core neutral carbohydrate chain, to which the sialic acid residues were attached. These findings suggest that the VH gene family in these anticarbohydrate antibodies is selected, depending primarily on the linkage of the sialic acid residues in carbohydrate Ag; these residues form the immunodominant sugar residue in the respective antigenic determinant.

Animals↗
PubMed1990

The concentration of tissue plasminogen activator and urokinase in plasma and tissues of patients with ovarian and uterine tumors.

The concentrations of tissue plasminogen activator (t-PA) and urokinase (UK) were measured in the plasma of patients with benign or malignant ovarian and uterine tumors. Plasma levels of t-PA were higher in patients with malignant ovarian and uterine tumors than in patients with benign tumors. Plasma UK levels were, however, not different between patients with ovarian and uterine tumors (benign or malignant) and normal persons. The concentrations of t-PA and UK of tissues of uterine myoma were lower than those in normal uterine muscular layer. UK levels of tissues of endometrial and cervical cancers were significantly higher than those in normal endometrium and uterine cervix, whereas t-PA levels were not different between these tumors compared with those in normal uterine tissues.

Female↗
PubMed1990

Prevention of severe bleeding by tranexamic acid in a patient with disseminated intravascular coagulation.

Severe bleeding took place in a patient when abdominal aneurysm was removed by operation. Bleeding continued after infusion of heparin, antithrombin III (ATIII), fresh platelets and fresh blood. Infusion of tranexamic acid resulted in an immediate cessation of bleeding and improvement of his general condition. Sometime after the cessation by the administration of tranexamic acid, severe bleeding started again, resulting in intraperitoneal hematoma formation. Second time bleeding also stopped after the administration of tranexamic acid. Major finding of plasma parameters of fibrinolysis is that alpha 2AP which had been unable to inhibit plasmin, became able to inhibit it after the administration of tranexamic acid.

Aged↗
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

Ethanol and acetaldehyde metabolism in cultured hepatocytes from chronic alcoholic rats.

In this study the authors analyzed ethanol (Et-OH) and acetaldehyde (Ac-CHO) metabolism in cultured hepatocytes isolated from chronic alcoholic rats. Hepatocytes were isolated and cultured from two groups of rats, one was fed with a liquid diet containing Et-OH and another was pair-fed with a control diet for 4 weeks. After 48 hours of the primary culture, Et-OH was added to the culture medium at a final concentration of 5 mM with or without 2 mM 4-methyl pyrazole (Py). Serial changes of Et-OH and Ac-CHO levels in the medium for 48 hours were determined in 4 groups of the alcohol alone, alcohol-Py, control and control-Py groups. In the alcohol alone and control groups, Et-OH disappearance rates (EDR), which are roughly equivalent to Et-OH oxidation rates in the hepatocytes, were significantly higher than those in the corresponding Py treated groups. In the two alcoholic groups, the EDR was significantly higher than those in the corresponding control groups. In cultured hepatocytes, 75-80% of Ac-CHO produced from Et-OH was oxidized. The increasing rates of Ac-CHO (AcICR), a function of Ac-CHO production and oxidation rates in the hepatocytes, increased in parallel with the increase in the EDR. However, the AcICR/EDR rate, which is a parameter of the Ac-CHO oxidation rate in the hepatocytes, was not different among the 4 groups. These results indicate that the cultured cells maintain the characteristics of Et-OH metabolism in chronic alcoholic rats and may also be used for the study of Et-OH and Ac-CHO metabolism as an in vitro model.

Acetaldehyde↗