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21.
Nobuyoshi Mikami Jun Yoshimura Hideo Kaneko Hirohiko Yamada Junshi Miyamoto 《Pest management science》1985,16(1):33-45
Upon single oral administration to rats, the mono-, di- and tri-glucose conjugates of [14C]-3-phenoxybenzyl alcohol ( I ) or the mono-glucose conjugate of [14C]-3-phenoxybenzoic acid ( II ) were rapidly hydrolysed and extensively eliminated in the urine mostly as the sulphate conjugate of 3-(4-hydroxyphenoxy)benzoic acid ( X ). The faecal elimination was a minor route, whereas the biliary excretion was about 42% of the dose and the glucuronide conjugates of I , II and X were common major metabolites. The biliary glucuronides were cleaved in the small intestine to the respective aglycones, which were reabsorbed, metabolised further, and excreted in the urine as the sulphate conjugate of X . Although small amounts of the mono-, di-and tri-glucosides were found in the 0.5-h blood and liver samples following oral administration of the tri-glucoside of I , they were not detected in the urine, bile or faeces. Similarly the sulphate conjugate was one of the major urinary metabolites of germ-free rats, dosed with the 14C-glucosides via the oral or the intraperitoneal route, although they were excreted unchanged in certain amounts in the urine and faeces. The glucose conjugates were cleaved in vitro by gut microflora and in various rat tissues, including blood, liver, small intestine and small intestinal mucosa. The tissue enzymes showed a different substrate specificity in hydrolysis of the glucosides. However, they were not cleaved in gastric juice, bile, pancreatic juice or urine. 相似文献
22.
Nobuyoshi Mikami Noriko Wakabayashi Hirohiko Yamada Junshi Miyamoto 《Pest management science》1984,15(6):531-542
The metabolism of 3-phenoxybenzoic acid, a common plant metabolite of deltamethrin, cypermethrin and fenvalerate, has been studied in abscised leaves of cabbage, cotton, cucumber, kidney bean and tomato plants. The [14C]-acid was readily converted into more polar conjugates by esterification with glucose, 6-O-malonylglucose, gentiobiose, cellobiose, glucosylxylose and two types of triglucose with different isomerism. Other metabolites identified were the glucosyl ether of 3-(4-hydroxyphenoxy)benzoic acid, and a 3-(2-hydroxyphenoxy)benzoic acid derivative with a total of two molar equivalents of glucose linked to the carboxyl and phenolic -OH groups. The conjugation pathways were somewhat plant-specific. The glucosylxylose ester was found only in cotton, and the cellobiose and triglucose esters were found only in tomato. All of the conjugates except the glucose and glucosylxylose esters were plant metabolites that had not been identified previously. Furthermore, this is the first report to show the presence of cellobiose and triglucose conjugates in plants. However, neither of the acetyl derivatives of the [14C]-triglucoside was identical with the synthetic deca-acetyl derivative of [1→6]-triglucoside. 相似文献
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Naohiro Takahashi Nobuyoshi Mikami Hirohiko Yamada Junshi Miyamoto 《Pest management science》1985,16(2):113-118
The hydrolysis of [14C] fenpropathrin ( I ) [(RS)-α-cyano-3-phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate] was studied in buffer solutions at pH 1.9–10.4, and in natural river and sea water at 25, 40, 55 and 65°C under laboratory conditions. The hydrolysis of I proceeded predominantly through neutral (pH independent) and base-catalysed processes in the regions below pH 3.9 and above pH 7.0, respectively, whereas both reactions occurred between pH 3.9 and 7.0. The rates of hydrolysis of I in buffer solutions were similar to those in one sample of river and one sample of sea water. If this obtains generally, it may be expected that the half-life of I in natural waters, normally within the range pH 5–9, will range from 1.54 to 1080 days at 40°C, 11.3 to 8520 days at 25°C and, by extrapolation of the data obtained in buffer solutions, 106 to 83 000 days at 10°C. The rate constants for hydrolysis of I in aqueous media can be expressed by: Where log kN = 9.60–(5.56 × 103 T?1) and log kB = 7.32–(2.56 × 103 T?1). The calculated rate constants were in good accord with the observed values in buffer solutions. Cleavage of the ester linkage was more rapid than hydration of the cyano group at any pH and temperature tested. 相似文献
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The peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC‐1 α) induces mitochondria biogenesis in skeletal muscles. To determine the relationships between PGC‐1 α and the muscle fiber types, the expression levels of PGC‐1 α were analyzed in porcine and bovine skeletal muscles. As a first step, the nucleotide sequences of the porcine and bovine PGC‐1 α were determined. The porcine and bovine PGC‐1 α cDNA encoded 796 amino acid sequences and showed 95.1% identity between the two species. The expression levels of the PGC‐1 α mRNA were analyzed in the same 10 skeletal muscles from four pigs and three cattle. The contents of porcine and bovine PGC‐1 α were higher in the tongue, masseter and diaphragm, and lower in the Biceps femoris, semimembranosus, Longissimus thoracis and semitendinosus muscles. The contents of myosin heavy chain slow‐type protein (MyHC‐slow) were also determined in the same muscles by ELISA. The analysis of MyHC‐slow showed results similar to those for the PGC‐1 α contents in all of the muscles except for the tongue. The content of MyHC‐slow in the tongue was the lowest among the porcine muscles, and moderate among the bovine muscles. The results suggest that PGC‐1 α relates to the development of oxidative muscle fibers, but is not the principal factor in determining type I fiber content. 相似文献
25.
Normal fecal samples were taken from lactating cows fed either a total mixed ration (TMR; n = 30) or pasture‐based diet (20) and from dry cows fed mainly on hay (15). Diarrheic fecal samples (n = 51) were collected from 21 sick dairy cows. Fecal analyses of ammonia, urea, lactate and volatile fatty acid (VFA) levels were used to evaluate colonic fermentation. Most normal feces had reasonably neutral pH, however, alkaline feces were observed in diarrheic cows. Although fecal lactate is higher in cows on grazing pasture, lactate levels were generally lower in the cows in the present study. Fecal VFA levels were higher in lactating cows than in dry cows. Elevated fecal urea was observed in diarrheic cows, however, many fecal samples in normal and diarrheic cows contained no urea. Fecal VFA levels in diarrheic cows were lower than in normal lactating cows, but were approximately equivalent to those in dry cows. Grazing or dry cows showed higher acetate and lower n‐butyrate proportions compared with TMR‐fed or diarrheic cows. Higher proportions of branched chain VFAs were observed in diarrheic cows, and the lowest level was observed in grazing cows. The present results indicate that intracolonic nitrogen equilibrium and proteolytic fermentation are altered by diarrheic status. 相似文献
26.
Twenty-eight strains of Pseudomonas syringae pv. actinidiae isolated in 1984, 1987 and 1988 from kiwifruit orchards in Japan were tested for their resistance to copper sulfate. All strains
isolated in 1984 were copper sensitive with a minimum inhibitory concentration (MIC) of cupric sulfate of 0.75 mM. However,
some strains isolated in 1987 and 1988 were resistant, with the MIC ranging from 2.25 to 3.0 mM. All copper-resistant strains
contained at least one of two plasmids, pPaCul (about 70.5 kb) or pPaCu2 (about 280 kb), or both. In a copper-resistant strain
Pa429, the location of the copper-resistance gene(s) was examined by insertional inactivation with Tn5. The MIC of copper sulfate in the copper-sensitive mutant obtained by Tn5 tagging decreased from 2.75 to 0.75 mM. The 14.5 kb BamHI fragment, designated pPaCuB14, containing the same locus mutagenized with Tn5 was cloned from pPaCu1. However, pPaCuB14 did not confer copper resistance in the transformant of copper-sensitive strain
Pa21R, suggesting that this clone did not contain a full set of copper-resistance gene(s). Then a cosmid library of pPaCu1
was constructed and six cosmid clones hybridized with pPaCuB14 were selected. One of the six cosmids, designated pPaCuC1,
conferred a near wild-type level of copper resistance in the transformant of the copper-sensitive strain. pPaCuC1 had a homologous
region that hybridized with all of the PCR-amplifled fragments of copA, copB, copR, and copS genes of P. syringae pv. tomato. DNA sequence analysis of the homologous region revealed the existence of four open reading frames (ORF A, B, R and S) oriented
in the same direction. The predicted amino acid sequences of ORF A, B, R and S had 80, 70, 97 and 95% identity with CopA,
B, R and S of P. syringae pv. tomato, respectively.
Received 5 July 2001/ Accepted in revised form 27 September 2001 相似文献
27.
Satoshi Gotoda Nobuyoshi Takahashi Hirofumi Nakagawa Mitsuyuki Murakami Tomoko Takechi Tomozo Komura Toshiro Uchida Yasushi Takagi 《Pest management science》1998,52(4):309-320
A series of novel 6-(1,2,4-triazol-4-yl) chromone and -1-thiochromone (benzo[b]thiazin-4-one) derivatives was obtained by cyclisation via thiosemicarbazides which were prepared by reaction of hydrazines and the corresponding isothiocyanates. Their fungicidal activity was evaluated against the rice blast fungus Pyricularia oryzae. Of this series, 2,5,8-trimethyl-6-(1-propyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl) chromone, 6-(1-butyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone, 6-(1-hexyl-3-methyl-5-thioxo-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone and 6-(1-allyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone were highly active (pEC50>6·0). Structure–activity relationship studies using the capacity factor k′ as a hydrophobicity index suggested that the log k′ optimum for 2,5,8-trimethyl-chromone and -1-thiochromone derivatives was around 1·0, equivalent to a log Pow value of c. 4·4. © 1998 SCI 相似文献
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Ishii N Nakahigashi K Baba T Robert M Soga T Kanai A Hirasawa T Naba M Hirai K Hoque A Ho PY Kakazu Y Sugawara K Igarashi S Harada S Masuda T Sugiyama N Togashi T Hasegawa M Takai Y Yugi K Arakawa K Iwata N Toya Y Nakayama Y Nishioka T Shimizu K Mori H Tomita M 《Science (New York, N.Y.)》2007,316(5824):593-597
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations. 相似文献