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Volume 19, Issue 2
Displaying 1-15 of 15 articles from this issue
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Keiichi NAGATA, Tadashi MIYATA1994 Volume 19 Issue 2 Pages 73-77
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSThe differences in the effects of the (R, S)-S isomer of fenvalerate, (R, S)-alpha-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)-isovalerate on the electrophysiological activity of the central and peripheral nervous systems have been studied in the American cockroach, Periplaneta americana (L.). The (R, S)-S isomer of fenvalerate produced an increase followed by a decrease in impulse frequency of both nervous systems. In the central nervous system, the frequency level fluctuated among the each nerve impulse isolated from external recording following application of the (R, S)-S isomer of fenvalerate. The maximum frequency of repetitive firing in each nerve was not significantly different. In the peripheral nervous system, the process of intoxication was nearly identical to that of the central nervous system except that a change of frequency was not observed. The time required for the inhibition of spontaneous discharge following the application of the (R, S)-S isomer of fenvalerate was longer in the central nervous system as compared to the peripheral nervous system. There was no significant difference with regard to the times to cessation spontaneous nerve activity or the maximum frequency of repetitive firing induced by fenvalerate between central and peripheral nervous system activities. These results indicate that one major difference between the peripheral and the central nervous systems regarding the effect of the (R, S)-S isomer of fenvalerate on each nervous system is the onset time of the toxic effect after application.View full abstractDownload PDF (529K) -
Eiichi MINAMI, Ikuo ANDO1994 Volume 19 Issue 2 Pages 79-83
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSProbenazole (3-allyloxy-1, 2-benzisothiazole-1, 1-dioxide) induces a resistance reaction in rice plants (Oryza sativa cv. Nipponbare) against infection by the rice blast fungus, Pyricularia oryzae. A cDNA clone of which the mRNAs were enriched by treatment with probenazole was isolated by the differential screening method. The transcript for the clone was abundant in the green leaves, stems and spikelets. The amounts of mRNAs for the small subunit of ribulose 1, 5-bisphosphate carboxylase and the light-harvesting chlorophyll a/b-binding protein drastically decreased 48hr after inoculation, indicating that these house-keeping genes are rapidly repressed during the resistance reaction induced by probenazole. These results suggest that probenazole regulates gene activities of rice plants infected with P. oryzae.View full abstractDownload PDF (6479K) -
Nucleophilic Substitution Reaction of Trichloromethyl-1, 3, 5-triazines with ArylaminesKazuya KOIZUMI, Yoshiko MIYAMOTO, Natsuko OKANO, Manabu MURAKAMI, Ko W ...1994 Volume 19 Issue 2 Pages 85-92
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSA series of 2-substituted-4-arylamino-6-trichloromethyl-1, 3, 5-triazines is one of the most interesting chemical species for nitrification-inhibitory activity. This type of compounds has conventionally been obtained by the rather laborious processes via following reactions, i. e., hydroxylation of 2-substituted-4, 6-bis(trichloromethyl)-1, 3, 5-triazines to 2-substituted-4-hydroxy-6-trichloromethyl-1, 3, 5-triazines, chlorination of the hydroxy-1, 3, 5-triazines to 2-substituted-4-chloro-6-trichloromethyl-1, 3, 5-triazines, followed by substitution reaction of the chloro-1, 3, 5-triazines with arylamines. A new method has recently been found which permits the direct nucleophilic replacement of one trichloromethyl group attached to a 1, 3, 5-triazine ring with an arylamino group. The desired replacement reaction of the trichloromethyl by an arylamino group is accomplished in the present of tertiary amines such as triethylamine. By this method, a lot of biologically active 2-substituted-4-arylamino-6-trichloromethyl-1, 3, 5-triazines can be synthesized from 2-substituted-4, 6-bis(trichloromethyl)-1, 3, 5-triazines.View full abstractDownload PDF (858K) -
Hotaka SAITO, Mitsuhiro HIRANO, Tadayoshi SHIGEOKA1994 Volume 19 Issue 2 Pages 93-101
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSUptake, distribution, metabolism and excretion of tebufenpyrad [N-(4-tert-butylbenzyl)-4-chloro-3-ethyl-1-methylpyrazole-5-carboxamide, Pyranica®], a synthetic acaricide, were studied with carp. Fish were exposed to 14C-tebufenpyrad treated water (1.2μg/l) for 28 days, followed by 14 days period for depuration. Bioconcentration factors (BCFs) of 14C reached a steady-state plateau within 7 days of exposure and its maximum BCF was 864. HPLC analysis showed that less than 4% of the 14C in whole fish was tebufenpyrad to give the maximum BCF of 29. Gall bladder bile contained the highest concentration of 14C, followed by gastrointestinal tract with the contents and hepatopancreas. Tebufenpyrad was not detected in the bile. An enzymatic treatment suggested that 84% of the 14C in bile were β-glucuronic acid conjugates. Major metabolic reactions of tebufenpyrad by carp were hydroxylation on the tert-butyl moiety, followed by oxidation to the carboxyl group and conjugation of the resultant metabolites with glucuronic acid. During the depuration phase, more than 98% of 14C were excreted from fish within 7 days with a half-life of 0.5 days. The results of this study strongly suggest that active biotransformation and excretion play important roles to lower the bioaccumulative potential of tebufenpyrad by carp.View full abstractDownload PDF (1035K) -
Ichiro MIURA, Takashi KAMAKURA, Shinichiro MAENO, Toshihiro NAGATA, Sh ...1994 Volume 19 Issue 2 Pages 103-109
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSMepanipyrim, N-(4-methyl-6-prop-1-ynylpyrimidin-2-yl)aniline, hardly inhibited the mycelial respiration and the syntheses of DNA, RNA, protein, lipids and cell walls in mycelia of Botrytis cinerea at 100μg/ml. By the treatment of mepanipyrim at 10-100μg/ml, each uptake of 14C-labeled glucose, acetate, uridine, thymidine, alanine or glucosamine by the mycelia of B. cinerea was inhibited, but no apparent uptake inhibition of these precursors was observed below 1μg/ml. The inhibition by mepanipyrim of the active transport process across the cellular membrane may bring about a chronic deficiency in most intracellular substrates essential for growth and development. However, the effect of mepanipyrim appeared not to be strong enough to disrupt the overall functions of cell membrane in B. cinerea; because it neither stimulated the leakage of protein, phosphate, glucose and electrolytes from the cells, nor influenced the bursting rate of protoplasts by osmotic shock.View full abstractDownload PDF (872K) -
Bioisosterism in Δ21-, 2, 4-Thiadiazolines and Related Heterocyclic CompoundsKenji HAGIWARA, Akira NAKAYAMA1994 Volume 19 Issue 2 Pages 111-117
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSA series of fused Δ2-1, 2, 4-thiadiazoline derivatives (I) showed similar herbicidal activity to that of tetrahydrophthalimides (II) and 1, 2, 4-triazolin-3-ones (III). In order to understand the bioisosterism of I, II and III, steric and electrostatic properties of them were studied by means of molecular orbital calculations and computational techniques. The molecular electrostatic potentials of their model molecules were similar to each other in terms of the patterns of potential contours. The conformational analysis for the rotation of benzene ring in I-III indicated that they are flexible within some range of the rotation, and that they are commonly stable when the torsional angle is ca. 240°. The Carbo's similarity index was employed to quantify the electrostatic similarity of the molecules, and the values of the index were in the range of 0.83-0.93 when two of the molecules were superimposed by the least square fitting. The SIMPLEX optimization procedure was also examined to find the best superimposition to maximize the electrostatic similarity, and the obtained superimposed models were almost same as the ones by the least square fitting. Based upon such aspects, a hypothetical model of active structure was drawn to account for the bioisosterism of herbicides having dissimilar backbone structures.View full abstractDownload PDF (877K) -
Studies on Acyclic Nitroethene Compounds (Part 3)Takanori TABUCHI, Takafumi FUSAKA, Koichi IWANAGA, Isao MINAMIDA, Tets ...1994 Volume 19 Issue 2 Pages 119-125
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSModification of 1-methylamino-1-[N-methyl-N-(3-pyridylmethyl)]amino-2-nitroethene (1) was progressed stepwise with reference to the insecticidal activities of compounds prepared so far against Nilaparvata lugens. Firstly, we replaced the methylene of 1 with a chemical bond (3), an ethylidene (4) or an ethylene (5), and found that the activity of 1-methylamino-1-[N-methyl-N-(3-pyridyl)]amino-2-nitroethene (3) was higher than others and comparable to 1. Secondly, introduction of a methyl (6), a methoxy (7) or a chloro group (8) into the 6-position of the pyridine of 3 afforded 1-N-(6-chloro-3-pyridyl)-N-methylamino-1-methylamino-2-nitroethene (8) as the best among the compounds derived. Finally, substitution of either one or both of the methyl groups of 8 with a hydrogen or higher alkyls (9-15) or formylation of 8 gave rise to 1-[N-(6-chloro-3-pyridyl)-N-methyl]amino-1-(N-formyl-N-methyl)amino-2-nitroethene (17) as the top of the derivatives which exhibited potent activity against not only N. lugens but also Spodoptera litura.View full abstractDownload PDF (771K) -
Comparison of Plant Cell Suspension Cultures and SeedlingsMichel COUDERCHET, Brigitte BROZIO, Peter BÖGER1994 Volume 19 Issue 2 Pages 127-135
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSBiological activity and fate of metazachlor were compared in cell suspension cultures and seedlings from rice and spinach. Growth of cell cultures was not (rice) or only slightly (spinach) inhibited by 200μM and 100μM metazachlor, respectively. In contrast, seedling growth was halved with 50nM metazachlor (rice) and 35% less with 100μM (spinach). In rice seedlings, 0.1μM metazachlor significantly decreased fatty acid desaturation, while 100-200μM had little or no effect in the other 3 systems. Cell suspension cultures weree more tolerant to metazachlor than the corresponding plant systems. Uptake could not explain tolerance since it was lowest in the most sensitive system (rice seedlings). All systems were able to metabolize metazachlor. After 72hr spinach cell culture and seedlings fed with 200μM metazachlor still contained 3.3 and 48μM parent herbicide, respectively. ice seedlings incubated with 0.1μM herbicide contained only 18nM of parent metazachlor after 24hr. This low but still very phytotoxic concentration of parent metazachlor in rice seedlings compared with the high and yet non-toxic concentration found in spinach suggests that metabolism via glutathione conjugation might not be the only protection mechanism in tolerant plants.View full abstractDownload PDF (1252K) -
Studies on Sulfonylureas with Fused Heterocycles (Part 3)Kazunari OHTA, Shigeyuki ITOH, Yasuyuki KANDOU, Harutoshi YOSHIKAWA, Y ...1994 Volume 19 Issue 2 Pages 137-141
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
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Yoichi ASO1994 Volume 19 Issue 2 Pages S61-S65
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
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Recognition and Responses in Suspension-cultured Rice CellsNaoto SHIBUYA1994 Volume 19 Issue 2 Pages S67-S71
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
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[in Japanese]1994 Volume 19 Issue 2 Pages S75-S76
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
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[in Japanese]1994 Volume 19 Issue 2 Pages S77-S78
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
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[in Japanese]1994 Volume 19 Issue 2 Pages S79-S80
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSDownload PDF (210K) -
[in Japanese]1994 Volume 19 Issue 2 Pages S81-S82
Published: May 02, 1994
Released on J-STAGE: August 05, 2010
JOURNAL FREE ACCESSDownload PDF (278K)
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