Search PubMed⌕ Search

Biomedical subjects

K Fujimoto

Publications and source records attributed to K Fujimoto.

At least 595 records · Page 33Linked to original sources

Photochemical deoxyribose C2' oxidation in 5-iodouracil-containing hexanucleotide.

To investigate photochemistry of 5-iodouracil (IU) in DNA, photoreaction of IU-containing oligonucleotides was examined. It was found that d(GCAIU G C) 2 undergoes selective photochemical C1' and C2' oxidation at the 5' side of IU residue to provide ribonolactone-containing hexamer 1 and erythrose-containing hexamer 2. Upon heating under alkaline conditions, erythrose-containing hexamer 2 was found to undergo retro aldol condensation to provide two fragments having glycolaldehyde termini.

Deoxyribose↗

Measurement of serum IgE antibodies against Japanese cedar pollen (Cryptomeria japonica) in Japanese monkeys (Macaca fuscata) with pollinosis.

IgE antibodies against allergens of Japanese cedar (Cryptomeria japonica, CJ) pollen in the serum of seven Japanese monkeys (Macaca fuscata) with pollinosis were measured by fluorometric indirect enzyme-linked immunosorbent assay (ELISA). All of the monkeys were found to have specific IgE to the crude pollen antigen. The specific IgE levels were well correlated with those determined by the Pharmacia CAP system. IgE antibodies were then assayed with two kinds of purified allergens (Cry j I and Cry j II) by the ELISA. We found that five monkeys had specific IgE to both allergens, although the other two had IgE only to Cry j I or Cry j II; there is different immune responsiveness to the two major allergens in the monkeys.

Allergens↗

Cytochemistry of protein kinase C and Na-K-ATPase in rabbit ciliary processes treated with phorbol ester.

Immunocytochemical localization of protein kinase C (PKC) in rabbit ciliary processes was investigated using anti-PKC monoclonal antibodies (MAbs) against rabbit Types 1, 2, and 3 PKC. Specific immunolabeling was observed in nonpigmented epithelial (NPE) cells and in the capillaries of the ciliary processes with anti-Types 2 and 3 MAbs. No apparent staining was seen with anti-Type 1 MAbs. Immunoelectron microscopy of Types 2 and 3 MAbs revealed a diffuse distribution of immunoreactive PKC in the cytoplasm, in the nucleus, and on the plasma membrane in the NPE cells. When incubated with phorbol 12-myristate 13-acetate (PMA), the distribution of PKC was basically similar to that of the untreated group. However, the labelling density on the plasma membrane at basolateral interdigitation increased considerably for anti-Types 2 and 3 PKC MAbs. In addition, the enzyme cytochemical activity of Na-K-ATPase (ouabain-sensitive K-NPPase) and its change after PMA administration in the ciliary processes were observed. An intense reaction was seen on the basolateral plasma membrane of the NPE cells. In the PMA-treated group, the enzyme activity of Na-K-ATPase apparently was decreased. These findings provide evidence that PKC plays a crucial role in the function of the NPE cells of the ciliary processes, possibly in aqueous humor production.

4-Nitrophenylphosphatase↗

Synergistic effects of interleukin 3 and interleukin 11 on murine megakaryopoiesis in serum-free culture.

We investigated the effects of interleukin 11 (IL-11) on murine megakaryopoiesis in serum-free cultures, using nonadherent, nonphagocytic, and T-cell-depleted bone marrow cells. IL-11 alone had no influence on megakaryocyte (Meg) colony formation in serum-free methylcellulose cultures, but it significantly enhanced the growth of Meg and granulocyte-macrophage-Meg colonies supported by optimal and suboptimal concentrations of interleukin 3 (IL-3). IL-11 also increased the size of IL-3-dependent Meg colonies as well as increasing the size and DNA content of constituent Meg. In liquid cultures, IL-11 alone did not increase the number of Meg, but it enhanced their size and acetylcholinesterase (AchE) levels. The addition of IL-11 to cultures containing suboptimal concentrations of IL-3 resulted in a synergistic increase of Meg AchE. These results suggest that IL-11, similarly to interleukin 6, has an effect on Meg and acts synergistically with IL-3 to augment murine megakaryopoiesis in vitro.

Acetylcholinesterase↗

Chemiluminescent simultaneous determination of phosphatidylcholine hydroperoxide and phosphatidylethanolamine hydroperoxide in the liver and brain of the rat.

The quantification of phospholipid hydroperoxides in biological tissues is important in order to know the degree of peroxidative damage of membrane lipids. For this purpose, optimal conditions for the chemiluminescent simultaneous assay of phosphatidylcholine hydroperoxide (PCOOH) and phosphatidylethanolamine hydroperoxide (PEOOH) in rat liver and brain were determined. A chemiluminescence detection-high performance liquid chromatography (CL-HPLC) method that incorporates cytochrome c and luminol as a post-column hydroperoxide-specific luminescent reagent was used (Miyazawa et al. 1987. Anal. Lett. 20: 915-925; Miyazawa. 1989. Free Radical Biol. Med. 7: 209-217). An n-propylamine-bound silica column with hexane-2-propanol-methanol-water 5:7:2:1 (v/v/v/v) (flow rate 1.0 ml/min) as eluant was used to determine both PCOOH and PEOOH, which were separated from each other and from other lipids and lipid-soluble antioxidants. High reproducibility and sensitivity as low as 10 pmol hydroperoxide-O2 were observed with a mixture of 10 micrograms/ml cytochrome c and 2 micrograms/ml luminol in 50 mM borate buffer (pH 10.0, flow rate 1.1 ml/min) as luminescent reagent and a post-column mixing joint temperature of 40 degrees C. Using the established analytical conditions, it was confirmed that both PCOOH (1324 +/- 122 pmol/g liver, 114 +/- 18 pmol/g brain, mean +/- SD) and PEOOH (728 +/- 89 pmol/g liver, 349 +/- 60 pmol/g brain, mean +/- SD) are present in the liver and brain of Sprague-Dawley rats bred on a slightly modified AIN-76A semisynthetic diet for 3 months. The phospholipid hydroperoxide content in the rat liver was shown to be affected by dietary oils, but not significantly affected in the brain.

Animals↗

[A case of myxedema heart with serial endomyocardial biopsy].

We report a case of middle-aged woman with myxedema heart who presented congestive heart failure due to myocardial damage caused by myxedema, and showed reversible and irreversible myocardial change proven by serial endomyocardial biopsy. She was admitted to our hospital because of facial, peripheral edema and dyspnea. On admission, chest X-P revealed severe cardiomegaly (CTR 70%) and bilateral pleural effusion. Electrocardiogram showed low voltage. Echocardiogram and chest CT revealed a large amount of pericardial effusion. No significant stenosis was observed on a coronary arteriogram. Laboratory data showed elevated TC, CPK, LDH values and immunological test indicated high titer of thyroid test and microsome test. Thyroid function test revealed primary hypothyroidism with low T3, low T4 and high TSH levels. Replacement therapy for hypothyroidism in addition to digitalis and diuretics++ has been started. Seven months after initial evaluation, this therapy has resulted in dramatic clinical improvement. Transvenous right ventricular endomyocardial biopsy demonstrated vacuolated degeneration on admission and improvement of vacuolated degeneration with a slight degree of fibrosis after therapy. This pathological finding suggests that myxedema heart is able to produce both reversible and irreversible myocardial damage.

Aged↗

[A case of pulmonary tuberculosis associated with severe skin eruption, prominent eosinophilia, and liver dysfunction induced by streptomycin].

A 42-year-old woman was admitted because of cough, sputum, and fever. A chest roentgenogram revealed a nodular density in the left upper lung field with satellite lesions compatible with tuberculoma. Mycobacterium tuberculosis was detected from sputum. Five weeks after starting the treatment with 0.4 g/day of isoniazid, 0.45 g/day of rifampicin, and 0.75 g/day of streptomycin, she showed itching erythema in the trunk. The white blood cell count was 4,500/mm3 with 14% eosinophils, and serum transaminases were slightly increased (GOT 101 U/L, GPT 74 U/L). Although isoniazid and rifampicin were stopped, the erythema with exfoliation spread to her extremities, suggesting exfoliative dermatitis. The white blood cell count reached 15,990/mm3 with 68% eosinophils (10,810/mm3). Stimulation indices measured with the lymphocyte stimulation test (LST) were 109% with rifampicin, 140% with isoniazid, and 275% with streptomycin, suggesting streptomycin-induced allergy. After cessation of streptomycin, the symptoms gradually improved. After the reaction had subsided, the treatment with isoniazid, rifampicin, and ethambutol was resumed, but she showed no further adverse reactions. LST seems to be very useful to identify the drug or drugs responsible for the reactions occurred during the treatment by antituberculosis drugs.

Adult↗

[Münchhausen syndrome with severe iron deficiency anemia].

A patient with Münchhausen syndrome who had severe iron deficiency anemia (IDA) is reported. A 31 year-old female presented with irregular genital bleeding. However, gynecological examination disclosed no evidence of specific disorders causing bleeding. Tests for bleeding tendency and hemolysis were all negative. Although massive bleeding was absent, she had three episodes of a rapid fall in Hb level associated with marked fatigue and weakness, and subsequently rapidly developed serious IDA afterwards. Factitious bleeding was strongly suspected. Blood transfusion performed when the patient was not being watched failed to increase Hb, while transfusions given while the patient was watched were effective. She was not cooperative throughout the hospital course and was discharged on her own request. In outpatient clinic, the diagnosis was confirmed by the evidence that she diluted her own blood samples.

Adult↗

Misoprostol accelerates colonic mucosal repair in acetic acid-induced colitis.

The objectives of this study were 1) to determine whether misoprostol (MISO) (prostaglandin E1 analog) pretreatment protects the colonic mucosa from the injurious effects of acetic acid by attenuating the initial injury or by enhancing the rate of repair and 2) to assess the relationship between the protective effect of MISO pretreatment and mucosal ornithine decarboxylase activity in the inflamed colon. We found that the intrarectal administration of acetic acid caused rapid and extensive injury to the colonic mucosa, such that mucosal permeability increased 88-, 75-, 26-, 7.5- and 9.3-fold at 1, 2, 6, 24 and 48 hr after the enema, respectively. Intrarectal pretreatment with 50 micrograms of MISO for 30 min did not attenuate the increase in mucosal permeability at 1 hr after enema; however, it did significantly reduce mucosal permeability by 50 to 60% at 2, 6 and 48 hr after enema. We also demonstrated that acetic acid produced an 8.4-fold increase in colonic myeloperoxidase activity and a 1.8-fold increase in colonic weight at 48 hr after enema. MISO significantly reduced the increases in both myeloperoxidase activity and colon weight. Ornithine decarboxylase activity in the descending colon of vehicle-pretreated animals increased significantly only at 24 hr after the acetic acid enema. In addition, MISO pretreatment followed by acetic acid enema resulted in significantly higher ornithine decarboxylase activities in the descending colon at 2 and 6 hr, compared with the vehicle plus acetic acid and MISO plus saline groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetates↗

Increased serum levels of basic fibroblast growth factor in patients with renal cell carcinoma.

The serum level and urinary output of basic and acidic fibroblast growth factors (FGFs) were measured by sandwich enzyme immunoassay (EIA) in patients with renal cell carcinoma. In over fifty percent (16/31) of renal cell carcinoma patients, basic FGF was elevated (greater than 30 pg/ml) in their sera. There is relatively good correlation between serum levels of basic FGF and tumor stage or grade, while urinary daily output of basic FGF did not correlate with increased malignancy. The present results indicate that serum basic FGF level of patients with renal cell carcinoma is a useful diagnostic and prognostic marker for renal cell carcinoma. On the other hand, acidic FGF was not detectable in all sera and urine.

Antibodies, Monoclonal↗

Presynaptic localization of histamine H3-receptors in rat brain.

The localization of histamine H3-receptors in subcellular fractions from the rat brain was examined in a [3H] (R) alpha-methylhistamine binding assay and compared with those of histamine H1- and adrenaline alpha 1- and alpha 2-receptors. Major [3H](R) alpha-methylhistamine binding sites with increased specific activities ([3H]ligand binding vs. protein amount) were recovered from the P2 fraction by differential centrifugation. Minor [3H](R)alpha-methylhistamine binding sites with increased specific activities were also detected in the P3 fraction. Further subfractionation of the P2 fraction by discontinuous sucrose density gradient centrifugation showed major recoveries of [3H](R)alpha-methylhistamine binding in myelin (MYE) and synaptic plasma membrane (SPM) fractions. A further increase in specific activity was observed in the MYE fraction, but the SPM fraction showed no significant increase in specific activity. Adrenaline alpha 2-receptors, the pre-synaptic autoreceptors, in a [3H] yohimbine binding assay showed distribution patterns similar to histamine H3-receptors. On the other hand, post-synaptic histamine H1- and adrenaline alpha 1-receptors were closely localized and distributed mainly in the SPM fraction with increased specific activity. Only a negligible amount was recovered in the MYE fraction, unlike the histamine H3- and adrenaline alpha 2-receptors.

Animals↗

Purification of achatin-I from the atria of the African giant snail, Achatina fulica, and its possible function.

Achatin-I previously purified from the ganglia of the African giant snail Achatina fulica was isolated from the atria of this snail. Achatin-I appeared to enhance the cardiac activity in two ways; centrally this peptide increased impulse frequency and produced spike broadening of the identified heart excitatory neuron, PON, and peripherally it enhanced amplitude and frequency of the heart beat. Achatin-I showed excitatory actions not only on the heart but on several other muscles.

Amino Acid Sequence↗

alpha-Glucosidase II-deficient cells use endo alpha-mannosidase as a bypass route for N-linked oligosaccharide processing.

The kinetics of N-linked oligosaccharide processing and the structures of the processing intermediates have been examined in normal parental BW5147 mouse lymphoma cells and the alpha-glucosidase II-deficient PHAR2.7 mutant cells. The mutant cells accumulated glucosylated intermediates but were able to deglucosylate and process about 40% of their oligosaccharides to complex-type. This processing was not due to residual alpha-glucosidase II activity since the alpha-glucosidase inhibitors 1-deoxynojirimycin (DNJ) and N-butyl-DNJ did not prevent it. Parent cells also showed alpha-glucosidase II-independent processing in the presence of DNJ and N-butyl-DNJ. Membrane preparations from both parent and mutant cells had endo alpha-mannosidase activity, that is, split Glc1,2Man9GlcNAc to Glc1,2Man plus Man8GlcNAc, indicating that this was a candidate for an alternate route to complex oligosaccharide formation in the mutant cells. A balance study in which the cellular glycoproteins, intracellular water soluble saccharides, and saccharides secreted into the medium were isolated and analyzed from [2-3H]mannose-labeled mutant cells showed that the cells formed the di- and trisaccharides Glc1Man and Glc2Man in amounts equivalent to the deglucosylated oligosaccharides found in the cellular glycoproteins. This result shows unequivocally that the alpha-glucosidase II-deficient mutant cells use endo alpha-mannosidase as a bypass route for N-linked oligosaccharide processing.

1-Deoxynojirimycin↗

Purification of megakaryocyte differentiation activity from a human fibrous histiocytoma cell line: N-terminal sequence homology with activin A.

We purified a protein possessing a potent ability to induce the differentiation of a murine megakaryoblastic cell line, L8057, from the supernatant of a human fibrous histiocytoma cell line, KHM-5M. The protein, a homodimer of a molecular weight of 25-kDa, has an N-terminal sequence identical with that of the beta A-chain of inhibin, indicating that it is identical to or highly homologous with activin A. Thus, it is speculated that activin A or its homologue is involved in megakaryocytic differentiation.

Activins↗

Possible essentially of docosahexaenoic acid in Japanese monkey neonates: occurrence in colostrum and low biosynthetic capacity in neonate brains.

The importance of mother's milk as a source of docosahexaenoic acid (DHA) in Japanese monkey neonates was investigated. The DHA content in monkey colostrum total lipids was 2.2%, similar to or slightly higher than in humans. A comparison of the biosynthetic capacity of brain microsomes from monkeys of different age (up to 10 years) showed that chain elongation/desaturation of linolenic acid and eicosapentaenoic acid in neonates was significantly less pronounced than in adults. In particular, the formation of DHA, which is the product of delta 4 desaturase, was negligible. These results suggest that milk is an important source of DHA in Japanese monkey neonates.

Aging↗

Inhibitory effect of MK-801 (noncompetitive NMDA receptor antagonist) on kindling-induced synaptic potentiation in acutely prepared rabbits.

We investigated effects of a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801, on potentiation of field potentials elicited in the dentate gyrus by single shocks to the perforant path after kindling to the pathway in acutely prepared rabbits. MK-801, which was intracortically injected after the establishment of kindling-induced potentiation, remarkably and dose-dependently reduced the potentiation. These results suggest that activated NMDA receptors contribute substantially to the expression of kindling-induced potentiation.

Animals↗