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Biomedical subjects

S Murakami

Publications and source records attributed to S Murakami.

At least 811 records · Page 45Linked to original sources
PubMed1985

Quantitative structure-activity relationships in cytokinin agonistic and antagonistic pyrido[2,3-d]pyrimidine derivatives: insights into receptor topology.

2-(Methylthio)pyrido[2,3-d]pyrimidines having various alkylamino and anilino substituents at the 4-position were prepared and tested for their cytokinin agonistic and antagonistic activities by the tobacco callus bioassay. The alkyl series of compounds showed anticytokinin activity, whereas the anilino derivatives exhibited both cytokinin and anticytokinin activities depending on the structure and position of the benzene substituents. Quantitative structure-activity analyses were carried out for each class and for the combined set of compounds with use of physicochemical parameters and regression analysis, indicating that the quality of activity, agonistic or antagonistic, as well as the extent of activity, is significantly affected by the steric features of the molecule. On the basis of the present results and previous quantitative analyses on cytokinins and other classes of anticytokinins, a dimensional map for the cytokinin receptor site can be drawn, which can serve as the basis for the design of novel agonists and antagonists.

Arabidopsis Proteins↗
PubMed1985

Nucleotide sequence of a cloned woodchuck hepatitis virus genome: evolutional relationship between hepadnaviruses.

We have determined the complete nucleotide sequence of a cloned DNA of woodchuck hepatitis virus (WHV), the most oncogenic virus among hepadnaviruses. The genome, designated WHV2, is 3,320 base pairs long and contains four major open reading frames (ORFs) coded on the same strand of nucleotide sequence as in the human hepatitis B virus (HBV) genome. Comparison of the nucleotide sequence and amino acid sequences deduced from it among the genomes of various hepadnaviruses demonstrates that each protein shows an intrinsic property in conserving its amino acid sequence. A parameter, the ratio of the number of triplets with one-letter change but no amino acid substitution to the total number of triplets in which one-letter change occurred, was introduced to measure the intrinsic properties quantitatively. For each ORF, the parameter gave characteristic values in all combinations. Therefore, the relative evolutional distance between these hepadnaviruses can be measured by the amino acid substitution rate of any ORF. These comparisons suggest that (i) the difference between two WHV clones, WHV1 and WHV2, corresponds to that among clones of a HBV subtype, HBVadr, and (ii) WHV and ground squirrel hepatitis virus can be categorized in a way similar to the subgroups of HBV.

Amino Acid Sequence↗
PubMed1985

Coexistence of growth hormone releasing factor-like and tyrosine hydroxylase-like immunoreactivities in neurons of the rat arcuate nucleus.

Neurons synthesizing growth hormone releasing factor were detected by immunocytochemistry with specific antiserum against synthetic rat hypothalamic growth hormone releasing factor. Growth hormone releasing factor immunoreactive neurons which also showed tyrosine hydroxylase immunoreactivity were located in the ventrolateral part of the arcuate nucleus. The functional significance of this finding for anterior pituitary hormone secretion is discussed.

Animals↗
PubMed1985

Effect of water immersion stress on the biosynthesis of rat gastric glycoproteins with or without sulfate.

The biosynthesis of rat gastric glycoproteins with or without sulfate was investigated in rats subjected to restraint and water immersion stress. Studies were carried out in vitro in rat glandular stomach using 3H-glucosamine and 35S-sulfate. Labeled glycoproteins were extracted with 2% Triton X-100 and fractionated on Bio Gel A-1.5 m. Radioactivity incorporated into glycoproteins was estimated in the tissue as well as in the medium. The incorporation of 3H-glucosamine into the tissue was unchanged during the experimental period, while the release of 3H-labeled glycoproteins into the medium was markedly increased at 12 h after the onset of stress. The incorporation of 35S-sulfate into the tissue was decreased at 6 h and increased at 12 h. The release of 35S-labeled glycoproteins into the medium was not changed significantly. However, the change in the total radioactivity (tissue plus medium) of 3H was similar to that of 35S. These results suggest that the remarkable increase in the biosynthesis of glycoproteins and sulfated glycoproteins was closely related to reinforcement of defensive response. Furthermore, we investigated the effect of anti-ulcer agents on the biosynthesis of mucus glycoproteins. Cimetidine and atropine decreased the incorporation of radioactive precursors and the release of labeled glycoproteins into the incubation medium in vitro. AAHA (N-(N-acetyl-beta-alanyl)-L-histidine aluminum complex) and sofalcone (SU-88; 2-carboxymethoxy-4,4'-bis (3-methyl-2-butenyloxy) chalcone) increased the incorporation of radioactive precursors and the release of labeled glycoproteins into the medium. These observations indicate that anti-ulcer agents having different modes of action show different effects on the glycoprotein biosynthesis.

Animals↗
PubMed1985

[Changes in the biosynthetic activity of gastric glycoproteins during the healing process of acetic acid ulcer in rats].

Changes in the incorporation of 3H-glucosamine into the macromolecular glycoprotein during the healing process of acetic acid induced gastric ulcer in rats were sequentially examined in the ulcer region and the intact region at 2, 10, 40, 80 and 365 days after the operation. 1) The total radioactivity (Tissue + Medium) and the radioactivity which remained in the tissue after incubation of the ulcer region were increased significantly as compared with those of the control at 2 days after the operation (275, 175% of the control, respectively), and then total radioactivity returned to the control level. On the other hand, the radioactivity in the tissue was gradually decreased, and then it became 50% of the control at 365 days. In contrast, the incorporating activity into the macromolecular glycoproteins was decreased to 50% of the control at 2 days, and was once recovered to the control level at 10 days. After 40 days, it was again decreased to 50% of the control and became 30% at 365 days. 2) Changes in the incorporation of 3H-glucosamine into the macromolecular glycoproteins of the intact region of rats with ulcers were the same as that of the ulcer region. 3) Elution profiles of gel filtration of the macromolecular glycoproteins isolated from the relapse and recurrence region of rats with ulcers at 365 days were the same as that of the healing region, and their radioactivities were decreased to 30% of the control. The results suggested that such a decrease in the biosynthetic activity of the macromolecular glycoproteins extending over the whole gastric tissue is one of the reasons for the increased relapse and recurrence.

Acetates↗
PubMed1985

Determination by enzyme-linked immunosorbent assay (ELISA) of specific IgG antibody activities for diagnosis of farmer's lung disease.

The specific IgG antibodies to thermophilic actinomycetes in the sera from patients with farmer's lung disease were quantitated by an ELISA and the results thereof were compared with those obtained by the standard double immunodiffusion assay (Ouchterlony's method). All sera from patients with farmer's lung disease were precipitin positive to Thermoactinomyces vulgaris and/or Micropolyspora faeni by the Ouchterlony's method, and revealed significantly high levels of IgG antibody activities against these antigens by ELISA. We have found 18 precipitin-positive but asymptomatic subjects in a survey of the dairy farming population of the northern area of IWATE Prefecture. Their sera were precipitin positive to antigens related to the farmer's lung disease, however IgG antibody activities as determined by ELISA to these antigens was significantly lower in the group of asymptomatics than in the group of symptomatics. Precipitin negative dairy farming controls and normal controls living in the urban area revealed low antibody activities as determined by ELISA. From these studies, we concluded that the assay of specific IgG antibody activity to thermophilic actinomyces by ELISA is useful for the diagnosis and screening of farmer's lung disease.

Adult↗
PubMed1985

[Effect of recombinant alpha-interferon on advanced renal cell carcinoma].

The present study was undertaken to assess the efficacy of single agent chemotherapy with alpha A-interferon or alpha 2-interferon for metastatic renal cell carcinoma. alpha A and alpha 2-Interferon were administered i.m. at a primary dose of 3 X 10(6) units/day to 13 patients. Two patients (15%) showed partial response; 1 patient (8%), minor response; 5 patients (38%), no change; 6 patients (46%), progressive disease. These preliminary observations indicate that these interferons are active antitumor agents in patients with renal cell carcinoma.

Adenocarcinoma↗
PubMed1985

Squamous metaplasia of the trigone in women with recurrent cystitis syndrome.

Urocystic mucosal biopsies of the white patch on the trigone in 44 women complaining of dysuria and frequency with or without bacteriuria showed varying degrees of squamous metaplasia as well as submucosal fibrosis. The patients with more frequent episodes of such symptoms in the past had more severe squamous metaplasia with submucosal fibrosis. Introital bacteria were found in almost all patients with mild or moderate development of squamous metaplasia, but not in those with severe lesions. These facts suggest that introital bacteria may be one of the causative factors for the initiation and early development of these abnormal mucosal changes. However, the further progression to severe mucosal alteration seems to be independent of any bacteria and this severe mucosal alteration may result in recurrence of such symptoms.

Adolescent↗
PubMed1985

[Clinical observation of non-gonococcal urethritis].

Sixty-one male urethritis cases, 28 gonococcal urethritis and 33 nongonococcal urethritis (NGU), were out-patients at the Department of Urology, Asahi General Hospital, during the 4 months, Oct. 1, 1984-Jan. 31, 1985. Thirteen of the 33 NGU patients (39.4%) were infected with C. trachomatis (CT). The efficacy of Doxycycline and the route of infection was studied in the cases of CT-positive CT-negative-NGU. CT infection from prostitutes was not so frequent as in the other pathogen infection of NGU. The efficacy of Doxycycline (100 mg b.i.d. for 2 weeks) against CT infection was excellent in the disappearance of subjective complaints and that of white blood cells in the urethral discharge in the CT positive-NGU group (13/13), in comparison with CT negative-NGU group (7/18). The efficacy of Doxycycline against CT was also confirmed from the follow-up study by the isolation of CT and by detection of CT antigen from urethral swabs using FITC conjugated monoclonal antibody against CT antigen.

Chlamydia Infections↗
PubMed1984

Disruption of fore- and hindlimb coordination during overground locomotion in cats with bilateral serial hemisection of the spinal cord.

In order to investigate if inter-limb propriospinal reflexes participate in coordination of locomotive movements of fore- and hindlimbs, we examined the relations between fore- and hindlimbs during overground locomotion of adult cats with spinal cord lesions. In a group of cats (T-T preparations), the spinal cord was hemisected first at around Th12 and then at intervals of 37-126 days contralaterally at mid-thoracic level, propriospinal tracts being mostly severed in this group. In a second group of cats (C-T preparations), which received hemisections first at around C2 and then at intervals of 21-73 days at mid-thoracic level, propriospinal tracts were left intact at least on one side of the spinal cord. Control observations were also made in intact cats and those with single hemisections at C2 or Th12, or with double unilateral hemisections at Th6 and Th12. Thus, it was found that in both T-T and C-T preparations, step length of the forelimbs was shortened significantly, whereas that of the hindlimbs was significantly lengthened. Furthermore, phase relations between the fore- and hindlimbs were completely lost in these preparations, suggesting that the stepping generator for the forelimbs operates independently of that for the hindlimbs. In other single-hemisected or unilaterally double-hemisected preparations, by contrast, no such changes were observed. The close similarity of the results in T-T and C-T preparations, in spite of different degrees of impairment of propriospinal tracts in them, leads to a conclusion that inter-limb propriospinal reflexes play little role in coordination of locomotive movements of fore- and hindlimbs.

Animals↗
PubMed1984

Coronary artery steal via a large anastomosis between the coronary and bronchial arteries successfully treated by surgical division.

A 56-year-old woman is presented with a large coronary-artery-to-bronchial-artery anastomosis associated with aortitis syndrome. Her angina, which was the result of a coronary artery steal, was relieved by surgical division of the anastomotic vessel. Pulmonary artery obstruction, as a pulmonary lesion of aortitis syndrome, might increase the collateral flow from the coronary artery through the bronchial artery to the pulmonary circulation.

Angina, Unstable↗
PubMed1984

A thymic tumor with massive proliferation of myoid cells.

A case of thymic tumor, composed of both epithelial and myoid cells, was presented. The myoid cells occurred in clusters, and showed prominent proliferation between the nests of epithelial cells. The myoid cells had intracytoplasmic myofibrils, and there were foci of electron dense Z-lines along the course of these fibrils. Some of these cells possessed sarcomeres identical to those of striated-muscle cells. Histochemically, a significant amount of glycosaminoglycans was observed on the surface of the myoid cells.

Cell Division↗