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Biomedical subjects

S Ueda

Publications and source records attributed to S Ueda.

At least 739 records · Page 41Linked to original sources
PubMed1989

[Influences of anti-allergic drugs on superoxide generation from the hypoxanthine-xanthine oxidase system or polymorphonuclear leukocytes].

The influences of anti-allergic drugs on superoxide generation from the hypoxanthine-xanthine oxidase system or polymorphonuclear leukocytes (PMN) were studied by an electron spin resonance assay using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trapper. The intensity of DMPO-OOH signal generated from the hypoxanthine-xanthine oxidase system was not influenced by the presence of azelastine, ketotifen, disodium cromoglycate, mequitazine, or methylprednisolone, but it decreased in the presence of AA-673. A kinetic study showed that the second order rate constant for reaction between AA-673 and superoxide anion at pH 7.4 was 2.9 x 10(8)M-1S-1. The relative intensity of DMPO-OOH spin adduct generated from PMN stimulated with phorbol myristate acetate (PMA) or opsonized zymosan (OZ) significantly decreased in the presence of azelastine: from the PMN-PMA system, with 10.7 microM concentration of molar concentration causing 50% reduction of the signal intensity (IC50), while from the PMN-OZ system, with 10.5 microM concentration of IC50, and also decreased in the presence of mequitazine: from the PMN-PMA system, with 10.8 microM concentration of IC50, while from the PMN-OZ system, less than 2.0 microM concentration of IC50. These results suggest that some anti-allergic drugs may have anti-inflammatory and anti-oxidative actions due to scavenging superoxide radicals or due to inhibiting superoxide production.

Aminopyridines↗
PubMed1989

Hemoglobin Hope found in a patient with basal cell carcinoma of the genial region.

Hemoglobinopathy was detected in a 72-year-old female with basal cell carcinoma of the genial region during high-performance liquid chromatography of hemolysate for the assay of HbA1c. Structural analysis demonstrated that this abnormal hemoglobin was identical to Hb Hope [beta 136(H14)Gly----Asp]. No clinical or hematological abnormality was observed. A study of the family revealed that a younger sister and two sons of the propositus had the same hemoglobin variant. This is the second observation of Hb Hope in a Japanese family.

Aged↗
PubMed1989

[The molecular basis of HbH disease in a Japanese girl].

Hemoglobin H disease is often caused by deletion of three of the four alpha-globin genes (genotype: --/-alpha). We studied a Japanese girl who had microcytic hypochromic anemia, a decreased alpha/beta globin synthetic ratio and about 8% Hb H in her fresh hemolysate, by means of restriction endonuclease mapping of the alpha-like gene complex (5'-zeta-phi zeta-phi alpha 2-phi alpha 1-alpha 2-alpha 1-theta-3') with zeta- and alpha-specific probes. It was found that the defect of one chromosome was associated with the removal of about 18 kb of DNA, known as --SEA type alpha-thalassemia-1, including the deletion of the part of phi alpha 2, phi alpha 1, alpha 2, alpha 1, and theta globin genes, while the other one was associated with the removal of 3.7 kb of DNA, known as rightward deletion type alpha-thalassemia-2. The results of a family study demonstrated that the deletion haplotype --SEA was inherited from her father's side and the other -alpha 3.7 from her mother's side.

Asian People↗
PubMed1989

The fine structures of the suprachiasmatic nucleus of the golden hamster.

The fine structure of the suprachiasmatic nucleus of the golden hamster was studied with special reference to the synaptic endings. The somata of SCN neurons contained well developed cytoplasmic organelles including the Golgi complex, mitochondria and polysomes. The nuclei had deeply invaginated nuclear membrane. Some neurons were characterized by the presence of a large number of granulated vesicles and an abundance of cytoplasmic organelles. Several kinds of synapses and gap junctions were also observed. Axo-somatic synapses were identified and could be differentiated based upon possessing two types of presynaptic elements. The first contained clear round synaptic vesicles (40-60 nm in diameter), the second contained clear round vesicles (40-60 nm in diameter) and dense cored vesicles (70-120 nm in diameter). Asymmetrical synaptic membrane thickening were observed on both the pre- and postsynaptic sides of most of the axosomatic synapses. Axo-dendritic synapses could also be divided into two sub-types according to their membrane specializations. In Type 1, the axon terminals contained both clear round vesicles and dense cored vesicles and formed asymmetrical synapses. Terminals in the second group (type 2) were characterized by symmetrical synapses that contained clear, round vesicles as well as dense cored vesicles. The type 1 terminals were evenly distributed throughout the SCN, but the type 2 terminals were encountered more frequently in the ventral SCN. These observations indicate that the ventral and dorsal components of the SCN may possess different functional roles.

Animals↗
PubMed1989

[Intravenous leiomyomatosis of the uterus with extension into the heart].

A case was reported concerning a successful removal of a leiomyoma with extension into the right atrium through the right ovarian vein and the inferior vena cava. The patient was a 72 year-old woman who had suddenly suffered dyspnea and palpitation. She was hospitalized, and a mass in the right atrium and the inferior vena cava was discovered using echocardiography and magnetic resonance imaging. A myxoma in the right atrium with a thrombus in the inferior vena cava was diagnosed preoperatively. The operation was performed in July 1987 by means of cardio-pulmonary bypass. During atriotomy of the right atrium, a large sausage-shaped mass of milky-pinkish color was found. Though the root of the mass was centered beyond the periphery of the inferior vena cava, most of it was removed through the right atrium. Immediately after extirpation of the tumor, hypotension and abdominal distention occurred in the patient, and emergency laparotomy was carried out. Retroperitoneal bleeding from the right ovarian vein occurred and the similar tumors were observed in the right ovarian vein. Intravenous leiomyomatosis of the uterus with extension into the heart is very rare, this being only the seventeenth case reported in literature. To the best of our knowledge, this was also the oldest patient on record. The good surgical method for this tumor seems to be total removal using cardio-pulmonary bypass and laparotomy at the same time.

Aged↗
PubMed1989

Effect of a collagen shield on cat corneal epithelial wound healing.

We have previously demonstrated that a corneal bandage lens made from porcine scleral collagen may be useful in treating various ocular surface problems. In order to determine whether the collagen shield would accelerate epithelial healing, a 7 mm diameter circular area in the center of the left cornea of ten domestic cats was mechanically deepithelialized. In five of the cats, a 14.5 mm non-cross-linked collagen shield was then placed on the cornea covering the wound. Another shield was applied 24 hr after surgery. The wound size was determined immediately after surgery and at 8-hr intervals until wound closure. Using analysis of variance for experiments with repeated observations, there was a significantly greater healing response in the treated group than in the control group. There was, however, no significant difference in slope between the two groups, suggesting that the shield did not increase the speed of epithelial cell migration. Rather, the effect of the shield was most pronounced during the first 8 hr after wounding. In contrast to that of the treated group, the mean defect radius of the control group was larger at t = 8 hr than at t = 0 hr. The earlier wound closure exhibited by the treated group, which may be due to protection and lubrication of the epithelial cells at the margins of the fresh wound, suggests that the collagen shield may be useful in treating corneal surface conditions of which deepithelialization is a component.

Animals↗
PubMed1989

Corneal and conjunctival changes in congenital erythropoietic porphyria.

Penetrating keratoplasty and conjunctival resection were performed on a 53-year-old woman with confirmed congenital erythropoietic porphyria. Corneal and conjunctival tissue samples, studied by light and electron microscopy, revealed inflammatory cells and a reduced keratocyte population. Vessels within the conjunctival and corneal stroma displayed a thickened basement membrane. Microfibrillar material was seen in the extracellular spaces of the conjunctival stroma. These changes are similar to those reported for ultraviolet light-exposed skin of porphyria patients. The Descemet's membrane lacked the normal fetal and postnatal banding. It presented as a homogeneous layer, consisting of uniform, densely packed collagen fibers, which suggests endothelial damage in utero. The corneal endothelium was severely damaged.

Conjunctiva↗
PubMed1989

[Experimental study of injury on the small intestine in acute portal vein occlusion and the following restoration of portal vein flow in rats--hemodynamics and lipid peroxidation].

This study was performed to clarify the relationship between hemodynamics, congestive damage, lipid peroxidation and intraluminal hemorrhage of the small intestine. Using 51Cr-red blood cells, with a temporary occlusion of the portal vein for 30 min. in rats, the hemodynamic, biochemical and histological changes were investigated. By occluding the portal vein, its pressure increased to a level eight times higher than normal, and destruction of the intestinal mucosa and an increase of TBA reactants were observed. The intraluminal hemorrhage of the intestine increased to a quantity 7.5 times higher than usual during portal vein occlusion, and it decreased gradually after reperfusion. At 120 min. after reperfusion, this amount remained high, but the administration of Allopurinol diminished its level. A technique of temporary simultaneous occlusion of the superior mesenteric artery or the bypass between the portal and jugular veins was effective in reducing the congestive damage on the intestine. During the occlusion of the portal vein, sudden and high pressure of the portal vein primarily causes congestive damage, and superoxide generated by a xanthine oxidase system during reperfusion may cause lipid peroxidation which induces reperfusion injury. Thus, the lipid peroxidation may accelerate the injury on the small intestine.

Allopurinol↗
PubMed1988

Sequence analysis of the gtfC gene from Streptococcus mutans GS-5.

The nucleotide sequence of the gtfC gene, which codes for glucosyltransferase synthesizing both water-soluble and water-insoluble glucans, and its flanking regions from Streptococcus mutans GS-5, was determined. Although the gtfC gene (4218 bp) is preceded by a Shine-Dalgarno (SD) sequence, a promoter-like sequence for this gene could not be identified. The gtfC gene product composed of 1375 amino acid residues (approx. 153 kDa) is generally hydrophilic with three small hydrophobic domains. Two direct repeating units were found near the C terminus of the peptide. The gtfC gene has extensive homology with the previously sequenced gtfB gene. The homologous regions correspond to the signal sequence, an internal region, and the direct repeating units of the peptide. An open reading frame preceded by an SD sequence and followed by an inverted repeat sequence was found immediately downstream from the gtfC gene. The combined sequences of the gtfB and gtfC genes as well as flanking regions suggest that the two gtf genes and the small downstream coding region could be coordinately expressed within an operon. The possible evolution of the gtfC gene in S. mutans GS-5 is also discussed.

Amino Acid Sequence↗
PubMed1988

Regional distribution of immunoreactive brain natriuretic peptide in porcine brain and spinal cord.

In order to elucidate the physiological functions of brain natriuretic peptide (BNP), radioimmunoassay for BNP was established and regional distribution of BNP in porcine brain and spinal cord was investigated. The concentration of immunoreactive (ir-) BNP in porcine whole brain was estimated to be 0.63 pmol/g, 13 times higher than that of ir-atrial natriuretic peptide (ANP). Highest concentrations of ir-BNP were found in the medulla-pons, striatum, and spinal cord. Medium concentration was noted in the hypothalamus. This distribution of ir-BNP in porcine brain was found to be different from that of ir-ANP simultaneously measured. Furthermore, BNP and BNP-32 were identified as two major forms of ir-BNP in porcine brain.

Amino Acid Sequence↗
PubMed1988

The presence of brain natriuretic peptide of 12,000 daltons in porcine heart.

Brain natriuretic peptide (BNP) and its N-terminally six amino acid extended form (BNP-32) have been identified in porcine brain. These peptides exert diuretic-natriuretic and hypotensive effects, and have remarkably high sequence homology to atrial natriuretic peptide (ANP). We have set up a radioimmunoassay system specific to BNP and surveyed immunoreactive (ir-) BNP in peripheral tissue. In porcine cardiac atrium, we found the highest concentration of ir-BNP. By using gel filtration and reverse phase high performance liquid chromatography, ir-BNP was characterized. Most of ir-BNP in the atrium was found to exist as a high molecular weight form of 12,000 daltons; less than 15% of the total ir-BNP exist as low molecular weight forms such as BNP and BNP-32. These results suggest that BNP functions as a circulating hormone in addition to the neuropeptide function in brain.

Amino Acid Sequence↗
PubMed1988

Methotrexate-induced resistance to dactinomycin in choriocarcinoma.

NaUCC-2, a choriocarcinoma cell line, was derived from a patient who had a very poor clinical response to combination chemotherapy. Methotrexate (MTX) might have inhibited the antitumor effect of dactinomycin. To investigate this point, in vitro studies were performed to determine the sensitivity and uptake of MTX and dactinomycin (administered individually and in combination) to NaUCC-2 and three other choriocarcinoma cell lines. Dihydrofolate reductase (DHFR) concentrations were studied as well. Although NaUCC-2 showed sensitivity to MTX and dactinomycin, which were comparable to the other cell lines when they were given separately, NaUCC-2 was unique in that the combination of MTX and dactinomycin was less lethal than dactinomycin given by itself. The uptake of MTX in NaUCC-2 was significantly higher than that in the other cell lines, and MTX also induced an increase in dactinomycin uptake in NaUCC-2. There was no significant difference in DHFR activity. Although additional studies are necessary to determine the mechanism responsible for this effect, these findings suggest that a mechanism other than drug uptake or DHFR activity must play a role in the drug resistance for choriocarcinoma. These findings also suggest that the most commonly used combination chemotherapy for choriocarcinoma, dactinomycin and MTX, may not always be the best method.

Adult↗
PubMed1988

Reinnervation of serotonin fibers in the denervated rat subcommissural organ by fetal raphe transplants. An immunohistochemical study.

The ability of axonal outgrowth of serotonin neurons in the implanted brain tissue of subcommissural organ (SCO) was immunohistochemically studied. The serotonin neuron system of the experimental rats was completely destroyed by the intraventricular injection of 5,6-dihydroxytryptamine. The raphe region of normal fetal rats was implanted into the caudal part of the third ventricle of the neurotoxic drug pretreated rats. The host brain was examined 3 months after transplantation. The numerous serotonin fibers were distributed in the SCO and periventricular region of the third ventricle of the host brain. The outgrowing serotonin fibers from the raphe transplant seemed to innervate the SCO with the target specificity.

Animals↗