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1.
2.
[3H]Dihydroergocryptine ([3H]DHE) was shown to bind to sites in membranes from neuroblastoma X glioma hybrid cells (NG 108-15) that had the characteristics expected of alpha-adrenergic receptors. The binding was saturable with 0.3 pmol [3H]DHE bound per mg of protein and of high affinity, with an apparent dissociation constant (KD) of 1.8 nM. The specificity of the binding site for various ligands was more similar to that of alpha 2 receptors than to that of alpha 1. No specific binding of [3H]WB-4101 was found in the membranes derived from NG 108 cells. This finding also indicated that the [3H]DHE binding site in the cell is the alpha 2 receptor. GTP lowered the affinity of agonists for the [3H]DHE binding site, although the nucleotide hardly affected the affinity of antagonists including [3H]DHE. 相似文献
3.
Reiko Yu-Ito Kazuko Ôba Ikuzo Uritani 《Bioscience, biotechnology, and biochemistry》2013,77(8):2087-2091
In addition to HMG-CoA reductase, another HMG-CoA utilizing enzyme is present in the Mt fraction of sweet potato root tissue and its activity interferes with the assay to HMG-CoA reductase activity. 相似文献
4.
The axial growth of de-coated cocklebur (Xanthium pennsylvanicumWallr.) seeds, whose axes were divided into 4 zones, was examinedin relation to the temperature-dependent shift of the effectof C2H4 on germination. At 23?C, where both C2H4 and CO2 stimulatedgermination, CO2 promoted the axial growth at the radicle tipzone, whereas C2H4 promoted growth in the proximal portion ofthe axis. At 33?C, C2H4 inhibited germination, and stronglysuppressed the growth at the radicle tip, whereas the effectof CO2 did not change. The inhibition of growth at the radicletip zone was alleviated by O2 enrichment, which also reversedthe inhibition of germination. It is thus apparent that thetemperature-dependent shift of the action of C2H4 is associatedwith a temperature-dependent responsiveness of the radicle tipzone to C2H4. Growth of the radicle tip zone was sensitive toNaN3, whereas the proximal portion was sensitive to benzohydroxamicacid, an inhibitor of alternative respiration, suggesting thatthere may be an increase in the operation of the alternativerespiration path along a gradient of axial tissue from the tiptowards the cotyledonary side. The effects of CO2 and C2H4 arediscussed in relation to the different respiratory activitiesin each axial zone of cocklebur seeds. (Received May 9, 1986; Accepted November 6, 1986) 相似文献
5.
Effect of Ethylene Action Inhibitors upon Wound-Induced Gene Expression in Tomato Pericarp 总被引:5,自引:4,他引:1 下载免费PDF全文
The contribution of wound-ethylene to wound-induced gene expression was investigated in unripe tomato pericarp using inhibitors of ethylene action. Wounded unripe tomato pericarp was treated with 2,5-norbornadiene or silver thiosulfate to inhibit specifically the induction of ethylene-dependent mRNA species. Poly(A)+ RNAs isolated from these tissues after 12 hours of wounding were translated in vitro in a rabbit reticulocyte lysate system and [35S]methionine-labeled polypeptides were compared to unwounded controls after separation by one and two-dimensional polyacrylamide gel electrophoresis. Results show that mechanical wounding induces a dramatic shift in gene expression (over 50 mRNA species) but expression of less than 15% of these genes is affected by the treatment with ethylene action inhibitors. A selective decrease in mRNAs coding for a 37 kilodalton doublet and 75 kilodalton polypeptides is observed in 2,5-norbornadiene and silver thiosulfate treated wounded pericarp. Levels of hydroxyproline-rich glycoprotein mRNAs induced in wounded tissue were not influenced by inhibitors of ethylene action. 相似文献
6.
Hakan Cancer Nobuaki Tamamaki Uuji Handa Minoru Hayashi Yoshiaki Nojyo 《Cell and tissue research》1990,262(1):53-57
Summary Injection of wheat-germ agglutinin-horseradish peroxidase conjugate (WGA-HRP) into the superior cervical ganglion (SCG) of the rat results in accumulation of WGA-HRP in sympathetic postganglionic neurons in the contralateral SCG. The sympathetic pathways involved and the mechanism underlying the labeling were investigated. The labeling in neurons in the contralateral SCG was apparent 6 h after injection and increased in intensity with longer survival times. The number of labeled neurons reached 1300 at 72 h after the injection. Transection of the external (ECN) or internal carotid nerves (ICN) resulted in considerable reduction in the number of labeled neurons. Combined transection of both ECN and ICN virtually eliminated labeling in the contralateral SCG. This provides strong evidence that these two nerves are the major pathways for WGA-HRP transport out of the SCG. No labeling was observed in the contralateral SCG following injection of horseradish peroxidase (HRP). Therefore, it seems unlikely that a direct nerve connection exists between the bilateral ganglia. Instead, the labeling of contralateral SCG neurons appears to depend on the transneuronal transport capacity of WGA-HRP, which conveys the marker in an anterograde direction along the postganglionic fibers to terminals in sympathetic target organs, and then delivers it transneuronally to contralateral SCG neurons. We suggest that the sympathetic nerve fibers originating in the bilateral SCGs run intermingled and are in close contact in their peripheral target organs. 相似文献
7.
Summary A 444leucine to proline mutation detected by a NciI polymorphism in the human glucocerebrosidase gene was studied to investigate the correlation of the three clinical phenotypes of Gaucher disease with this mutation in 11 Japanese patients with Gaucher disease (type I, 8 patients; type II, 1 patient; type III, 2 patients) and to determine the feasibility of the use of genomic probe DNA for carrier detection and prenatal diagnosis in 8 Japanese families with Gaucher disease and agreeable to family study (type I, 6 families; type III, 2 families). The homoallelic 444leucine to proline mutation was found only in patients with type I disease. Of the 8 type I patients, 5 had the homoallelic mutation and 2 had one mutant allele. One patient with type II disease did not have this mutant allele. Of the 2 type III patients, one had a single mutant allele whereas the other exhibited no mutation of this kind. These results suggest that the 444leucine to proline mutation is very common in the type I (non-neuronopathic form) disease and is not tightly associated only with neuronopathic types of Gaucher disease in Japanese patients. These findings seem to conflict with others showing that this mutation is partially responsible for the occurrence of neuronopathic Gaucher disease. Thus, the NciI polymorphism will not be useful for the diagnosis of subtypes of Gaucher disease. Carrier detection was feasible in three families with type I disease of the 8 families analyzed by the NciI polymorphism. 相似文献
8.
Hiroshi Suzuki Hideaki Taguchi Kazuko Nishimura Makoto Miyaji Akira Nakamura Hironori Nakajima 《Mycopathologia》1988,104(1):7-17
Summary The authors succeeded in establishing a murine model of systemic candidiasis being disseminated from the primary gastrointestinal lesions caused by oral inoculation of Candida albicans. Using this model, an attempt was made for detecting the Candida antigen by enzyme-linked immunosorbent assay using avidin-biotin (AB-ELISA) from the serum of infected mice.Gastrointestinal candidiasis was formed in all of the 20 mice treated with the drugs (antibiotics, antineoplastic agents, hydrocortisone, etc.) and inoculated orally with C. albicans. Fourteen of these mice suffered from submucosal candidiasis, and C. albicans was cultured from the visceral organs in 12 of them. The assay by AB-ELISA was able to detect 1.0 ng/ml Candida mannan in the mouse serum. The Candida antigen was detected in the sera of 11 of the 14 mice with submucosal candidiasis. However, the antigen could not be detected in the sera of the 6 mice with intramucosal candidiasis.The assay by AB-ELISA is more sensitive and specific for the diagnosis of systemic candidiasis than other serological assays. 相似文献
9.
Day-night changes in production of carbohydrate and protein by natural phytoplankton population from Lake Biwa, Japan 总被引:2,自引:0,他引:2
Hama Takeo; Matsunaga Katsuji; Handa Nobuhiko; Takahashi Mikio 《Journal of plankton research》1988,10(5):941-955
The 13C and gas chromatography-mass spectrometry (13C-GC-MS)method was applied to determine the day-night changes in thecomposition of photosynthetic products of the natural phytoplanktonpopulation from Lake Biwa, Japan. Glucose is the most abundantmonosaccharide in acid-hydrolyzable carbohydrate. The contributionof glucose was high in incubatesd samples in daytime and decreasedduring the night. Other monosaccharides (rhamnose, fucose, ribose,arabinose, xylose, mannose and galactose) and amino acids tendedto be produced throughout both day- and night-time. These resultssuggested that the carbon flows from glucose, which might constitutereserve glucan, to other monosaccharides and amino acids duringnight-time. The disproportionate production of glucose (reservedglucan) during daytime was thus partly cancelled out at night. 相似文献
10.
H K Wolf G R Dagenais J G Fodor R S Fynes S P Handa R B Haynes G A Klassen M G Myers N M Robitaille 《CMAJ》1988,139(6):507-512
Causal blood pressure measurements were recorded in two groups of men aged 40 to 64 years; of the 7024 men in metropolitan Saint John, NB, and the 4044 men in seven suburbs of Quebec who were asked, 5840 (83.1%) and 3097 (76.6%) respectively agreed to participate. Of the Saint John group 9.0% were taking antihypertensive drugs, as compared with only 3.3% of the Quebec group (p less than 0.0001). Among the treated subjects 33% in Saint John and 53% in Quebec still had a diastolic pressure greater than 95 mm Hg (p less than 0.01). Among the participants not taking antihypertensive drugs the systolic blood pressure increased with age, but the diastolic blood pressure increased only slightly up to 55 years of age and then decreased. On average the subjects in Saint John who were not being treated had a systolic pressure 6.2 mm Hg lower and a diastolic blood pressure 3.6 mm Hg lower than their Quebec counterparts (p less than 0.0001). This difference was observed in all the age groups and was not the result of the treatment of a greater proportion of the Saint John cohort. Despite the higher blood pressures and the smaller number receiving adequate treatment in the Quebec group, the rate of death due to coronary artery disease was 10% lower than that in the Saint John group. A bias in the data from Quebec may have influenced the magnitude of the differences between the two samples, but if present it should have underestimated the blood pressures in the Quebec group and therefore not have changed the outcome. 相似文献