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Biomedical subjects

M Asaka

Publications and source records attributed to M Asaka.

At least 253 records · Page 14Linked to original sources
PubMed1987

A new solid-phase synthesis of oligoribonucleotides by the phosphoro-p-anisidate method using tetrahydrofuranyl protection of 2'-hydroxyl groups.

Six nonaribonucleotides containing the 5'-splice site, one complementary nonamer and an octadecamer containing the 3'-splice site have been synthesized on a polymer support using the phosphoro-p-anisidate method. A 5'-linked 2'-O-tetrahydrofuranyl-N-protected nucleoside 3'-(o-chlorophenyl)phosphoro-p-anisidate was used as the starting nucleotide, and the chain elongated in the 3'-direction by removing the p-anisidate protecting group with isoamyl nitrite under neutral conditions. The octadecamer has been synthesized using dinucleotide blocks and a 3'-terminal trinucleotide.

Base Sequence↗
PubMed1987

Membranoproliferative glomerulonephritis associated with chronic hepatitis B in adults: pathogenetic role of HBsAg.

Two adult cases of membranoproliferative glomerulonephritis (MPGN) associated with chronic hepatitis B were reported. Serum HBsAg, HBeAg and anti-HBc were positive. Glomerular changes were essentially the same in both patients and consistent with MPGN type III. Immunofluorescence microscopy revealed diffuse granular and lumpy deposits of IgG, IgA, IgM, C1q and C3 along glomerular capillary walls and in mesangial areas. Granular deposition of HBsAg was observed along capillary walls and in mesangial areas, and the staining patterns were similar to those of immunoglobulins and complements in both patients. Glomerular deposition of HBeAg, however, was negative in one case, and only slight and segmental in the other case. These findings suggest that HBsAg rather than HBeAg may play a role in the pathogenesis of MPGN associated with hepatitis B virus infection in adults.

Antibodies, Viral↗
PubMed1987

Effect of the antiplatelet agents ticlopidine and dipyridamole on nephrotoxic serum nephritis in rats.

The effect of the antiplatelet agents, ticlopidine and dipyridamole, on nephrotoxic serum nephritis (NTN) was evaluated in rats. An accelerated form of NTN was induced with preimmunization of rabbit IgG 7 days before injection of rabbit antirat nephrotoxic serum. Twelve animals received a peroral dose of 20 mg of ticlopidine daily, and 12 animals received a peroral dose of 10 mg of dipyridamole twice daily for 7 days. It was shown that both ticlopidine and dipyridamole were able to significantly reduce urinary protein excretion. There was, however, no significant difference in glomerular changes between treated animals and nontreated controls. Ticlopidine and dipyridamole were found to suppress the development of proteinuria in accelerated NTN. Although the antiaggregative action of dipyridamole was relatively weak in vivo, dipyridamole was found to be rather effective on protein excretion in the present study. These results support the significant role of platelets in the development of proteinuria in glomerulonephritis, and it is suggested that dipyridamole may have an antiproteinuric effect other than inhibition of platelet aggregation.

Animals↗
PubMed1987

Effect of probucol on hyperlipidemia in patients with nephrotic syndrome.

We have evaluated the effect of the antihyperlipidemic agent probucol on hyperlipidemia in patients with nephrotic syndrome. Twelve patients with long-standing nephrotic syndrome received 500 mg of probucol daily for 12 weeks. Serum total cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol were significantly lowered with probucol treatment. There were no differences in urine protein, serum total protein, serum albumin and renal function before and after probucol treatment. No drug-related side effects were observed during our study. These results indicated that probucol was effective against hyperlipidemia and free from side effects in patients with persistent nephrotic syndrome. The use of probucol is therefore suggested to be advisable when antihyperlipidemic treatment is required in some subgroups of nephrotic syndrome.

Adult↗
PubMed1987

Effect of the anticomplementary agent, K-76 monocarboxylic acid, on experimental immune complex glomerulonephritis in rats.

We examined the effect of the anticomplementary agent K-76 monocarboxylic acid (K-76COOH), which is known to inhibit C5 activity, on immune complex glomerulonephritis in rats. Bovine serum albumin (BSA) nephritis was induced in rats by subcutaneous immunization and daily intravenous administration of BSA. K-76COOH (30 mg/kg) was administered intraperitoneally twice daily for 4 weeks. It was shown that K-76COOH would significantly reduce the development of proteinuria in the early stage of BSA nephritis, but it failed to suppress proteinuria in the late stage. There was no significant difference in glomerular changes between treated animals and non-treated controls. These findings suggest that C5, and the terminal complement components may play a significant role in protein excretion in the early stage of immune complex glomerulonephritis.

Animals↗
PubMed1986

Effect of the antiplatelet agents ticlopidine and dipyridamole on experimental immune complex glomerulonephritis in rats.

The effect of the antiplatelet agents ticlopidine and dipyridamole on immune complex glomerulonephritis in rats was evaluated. Bovine serum albumin (BSA) nephritis was induced in rats with subcutaneous immunization and intravenous dosage of BSA. Ticlopidine and dipyridamole were administered for 4 weeks before and for 7 days after onset of proteinuria. It was shown that both ticlopidine and dipyridamole could reduce the development of proteinuria when administered before the onset of proteinuria. Ticlopidine also reduced the amount of urinary protein after onset of proteinuria, and may thus be more effective against urinary protein excretion. When the antiplatelet agents were administered before onset of glomerulonephritis, blood urea nitrogen and serum creatinine levels were significantly lower, and glomerular hypercellularity and mesangial widening were milder in animals treated with ticlopidine than in controls. Glomerular deposition of BSA was less intense in treated animals than in nontreated controls. Thus, ticlopidine as well as dipyridamole was found to inhibit the development of proteinuria and glomerular alteration. It is suggested that ticlopidine could be more effective than dipyridamole against the development of immune complex glomerulonephritis in rats.

Animals↗
PubMed1985

Synthesis and properties of novel nucleic acid probes.

2'-O-Methyl derivatives of common ribonucleosides were prepared from appropriately protected nucleosides via the methylation of the 2'-hydroxyl groups with methyl iodide or diazomethane. These derivatives were converted into 2'-O-methylribonucleotide units and the guanosine derivative was linked to a polymer support. Thus, oligo(2'-O-methylribonucleotides) having the sequence of AmCmUmUmAmCmCmUmGm was synthesized in a stepwise manner by using the phosphotriester method. Thermal stabilities (Tm's) of the hybrid between the 2'-O-methyl ribooligomer and the complementary ribooligomer and of the related hybrids are compared. The synthesis of ribooligomer by a new approach is also described.

Base Sequence↗
PubMed1983

Radioimmunoassay of aldolase A. Determination of normal serum levels and increased serum concentration in cancer patients.

A radioimmunoassay specific for human aldolase A subunits was used to measure human aldolase A (ALD-A) in human serum. The double antibody competitive inhibition radioimmunoassay technique used radioiodinated purified ALD-A as ligand, chicken antisera specific for human ALD-A and rabbit antichicken IgG. The serum levels of ALD-A in 42 normal healthy subjects ranged from 130 to 210 ng/ml (mean average, 171 +/- 39 ng/ml). In 177 hospitalized patients without cancer, muscle diseases, or hemolytic anemia, the ALD-A serum levels ranged from 125 to 220 ng/ml. In contrast, 82% of 260 patients with various types of malignancy had ALD-A serum concentrations above the normal range. The CEA levels increased only 44% of the sera of 80 patients with cancer of the digestive tract, whereas the ALD-A levels were increased in 86% of the patients. The AFP levels were greater than 100 ng/ml in only 70% of the sera of 33 liver cell carcinoma patients, whereas the ALD-A levels were increased in 94% of these sera. The measurement of serum ALD-A by radioimmunoassay may be a valuable adjunct in the clinical diagnosis of certain cancer patients.

Adolescent↗
PubMed1983

Subunit-specific radioimmunoassay for aldolase A, B, and C subunits: clinical significance.

Radioimmunoassays specific for fructose-1, 6-diphosphate aldolase isozymes were developed for the quantification of human aldolase A, B and C. The method is a double-antibody radioimmunoassay using radioiodinated purified aldolase A, B and C as ligand, chicken antibodies to aldolase A, B and C, and rabbit antibodies to chicken IgG. The Iodogen method was used for the iodination of aldolase A, B and C in this study. Aldolase A was predominantly high in concentration in muscle, aldolase B was high in normal adult liver, and aldolase C was high in adult brain. Aldolase A was elevated in hepatoma tissue and hepatoma cell lines, where aldolase B was distinctly low. Normal serum levels for the three isozymes were determined. The aldolase A levels in serum obtained from 41 normal subjects were 170 +/- 39 ng/ml. Serum aldolase A levels were increased in many patients with cancer and muscle diseases, but were not increased in patients with hepatitis or other benign diseases. Serum aldolase B levels obtained from 11 normal subjects were 28.5 +/- 9.2 ng/ml. Serum aldolase B levels were increased in patients with hepatitis and correlated well with serum GPT levels. Serum aldolase C levels obtained from 12 normal subjects were 2.4 +/- 0.7 ng/ml. The determination of aldolase A, B and C by radioimmunoassay may be a valuable tool in biochemical and clinical studies of aldolase isozymes.

Animals↗
PubMed1983

Aldolase A isoenzyme levels in serum and tissues of patients with liver diseases.

A radioimmunoassay specific for human aldolase A was used to measure human aldolase A levels in human tissue and serum of patients with various liver diseases. The method was a double-antibody technique using radio-iodinated purified aldolase A, chicken antibody to aldolase A, and rabbit antibody to chicken immunoglobulin G. Normal liver tissue contains only a small amount of aldolase A. In contrast, aldolase A predominates in liver cell carcinoma tissue. Aldolase A levels in the sera of normal subjects were 171 +/- 39 ng/ml (mean +/- 2 SD). In almost all of the nonmalignant liver diseases, the aldolase A levels remained less than 210 ng/ml. The serum aldolase A levels increased remarkable only in fulminant hepatitis. in contrast, 32 of 34 patients with liver cell carcinoma and all of 29 patients with metastatic liver carcinoma showed clearly increased serum aldolase A levels. More patients with primary liver cell carcinoma had increased serum aldolase A levels than elevations of serum alpha-fetoprotein. These results suggest that the determination of aldolase A by radioimmunoassay may be useful to differentiate malignant form nonmalignant liver diseases.

Carcinoembryonic Antigen↗
PubMed1983

Biochemical and clinical studies of aldolase isozymes in human cancer.

Radioimmunoassays specific for ALD isozymes were developed for the quantification of human ALD-A, -B, and -C. The method is a double antibody radioimmunoassay consisting of purified radioiodinated ALD-A, -B, and C as ligand, chicken antibodies to ALD-A, -B, and -C, and rabbit antibodies to chicken IgG. The Iodogen method was used for the iodination of the purified isozymes. ALD-A was present in high concentration in muscle, ALD-B in adult liver, and ALD-C in adult brain. ALD-A was elevated in hepatoma tissue and hepatoma cell lines, whereas ALD-B was distinctly low. Normal serum levels for the three isozymes were determined. The ALD-A level in the serum from 41 normal subjects was 170 +/- 39 ng/ml. Serum ALD-A level was increased in many patients with cancer and muscle diseases, but not in patients with hepatitis or other benign diseases. Serum ALD-B level in 11 normal subjects was 28.5 +/- 9.2 ng/ml. Serum ALD-C level in 12 normal subjects was 2.4 +/- 0.7 ng/ml. The determination of ALD-A, -B, and -C by radioimmunoassay may be a valuable tool in biochemical and clinical studies of these isozymes.

Carcinoma, Hepatocellular↗
PubMed1983

Human aldolase B subunit-specific radioimmunoassay.

A radioimmunoassay was developed for the direct quantification of aldolase B in human serum and tissues. The method is a double antibody radioimmunoassay technique using radioiodinated aldolase B homopolymer as ligand, chicken antibodies to aldolase B and rabbit antibodies to chicken IgG. This radioimmunoassay was shown to be specific for the aldolase B subunit, with no cross-reactivity with either human aldolase A subunit or homopolymeric human aldolase C (C4). The lowest measurable amount by this method was 2 ng/ml. Aldolase B is predominantly found in normal liver tissue, with relatively high aldolase B levels also observed in kidney. Aldolase B levels in the serum obtained from 11 normal subjects ranged from 23 to 38 ng/ml, with a mean of 28.5 +/- 9.2 (S.D.) ng/ml. Almost all of patients with hepatitis had serum aldolase B levels greater than 30 ng/ml. In cancer patients, serum aldolase B was slightly elevated in patients with metastatic liver cancer and primary lever cell carcinoma, whereas no elevation of serum aldolase B was shown in patients without liver metastasis.

Chloramines↗
PubMed1983

[Effects of paromomycin sulfate on Diphyllobothrium latum infections].

About 50 mg/kg of paromomycin sulfate was administered orally in a single or 2 divided doses to patients with Diphyllobothrium latum infections. The following results were obtained. After the treatment with paromomycin sulfate mature strobilae were expelled in all of 7 patients with Diphyllobothrium latum infections. We couldn't find scolices in all cases. Although these stools were examined for 2 months after the treatment, the eggs of Diphyllobothrium latum were not identified. No side effects were observed in all cases. It was concluded that paromomycin sulfate was effective on the treatment of Diphyllobothrium latum infections.

Adult↗