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1.
Zhang WY Liu HQ Xie KQ Yin LL Li Y Kwik-Uribe CL Zhu XZ 《Biochemical and biophysical research communications》2006,345(1):508-515
The anti-inflammatory activity of the predominant procyanidin dimer in cocoa, dimer B2, was investigated in this study. Pretreatment of the procyanidin dimer B2 reduced COX-2 expression induced by the endotoxin lipopolysaccharide (LPS) in differentiated human monocytic cells (THP-1) in culture. To further elucidate the underlying mechanism of COX-2 inhibition by procyanidin, we examined their effects on the activation of extracellular signal-regulated protein kinase (ERK), Jun-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK), which are upstream enzymes known to regulate COX-2 expression in many cell types. Pretreatment with procyanidin dimer B2 decreased the activation of ERK, JNK, and p38 MAPK. In addition, procyanidin dimer B2 suppressed the NF-kappaB activation through stabilization of IkappaB proteins, suggesting that these signal-transducing enzymes could be potential targets for procyanidin dimer B2. By affecting the expression rather than the activity of COX-2, these in vitro data reported herein give further evidence on the anti-inflammatory protection by procyanidins. 相似文献
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A series of 2beta-[3'-(substituted benzyl)isoxazol-5-yl]- and 2beta-[3'-methyl-4'-(substituted phenyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes were prepared and evaluated for affinities at dopamine, serotonin, and norepinephrine transporters using competitive radioligand binding assays. The 2beta-[3'-(substituted benzyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes (3a-h) showed high binding affinities for the dopamine transporter (DAT). The IC(50) values ranged from 5.9 to 22nM. On the other hand, the 2beta-[3'-methyl-4'-(substituted phenyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes (4a-h), with IC(50) values ranging from 65 to 173nM, were approximately 3- to 25-fold less potent than the corresponding 2beta-[3'-(substituted benzyl)isoxazol]tropanes. All tested compounds were selective for the DAT relative to the norepinephrine transporter (NET) and serotonin transporter (5-HTT). 3Beta-(4-Methylphenyl)-2beta-[3'-(4-fluorobenzyl)isoxazol-5-yl]tropane (3b) with IC(50) of 5.9nM at the DAT and K(i)s of 454 and 113nM at the NET and 5-HTT, respectively, was the most potent and DAT-selective analog. Molecular modeling studies suggested that the rigid conformation of the isoxazole side chain in 4a-h might play an important role on their low DAT binding affinities. 相似文献
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It has been previously found in our laboratory that insect neuropeptide leucopyrokinin and [2-8]-leucopyrokinin, a truncated analog without the first aminoacid of leucopyrokinin peptide chain exert an antinociceptive effect in rats. The present study confirmed our previous results, and moreover it has been found that [d-Ala(5)]-[2-8]-leucopyrokinin, an analog of leucopyrokinin antagonized the antinociceptive effect of leucopyrokinin and of [2-8]-leucopyrokinin. We conclude that this synthetic analog is a probable leucopyrokinin antagonist. 相似文献
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Effects of 4-[beta-(diethylamino)-ethoxy]-benzophenone upon carotenogenesis in Rhodospirillum rubrum. 总被引:1,自引:0,他引:1
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Carotenoid production was determined in illuminated anaerobically maintained cultures of Rhodospirillum rubrum in media with and without 4-[beta-(diethylamino)-ethoxy]-benzophenone. In treated cultures, lycopene--which normally is not produced by R. rubrum--accumulated as the predominant pigment, and total carotenoids increased five- to sixfold. 相似文献
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Davies HM Ren P Kong N Sexton T Childers SR 《Bioorganic & medicinal chemistry letters》2001,11(4):487-489
3Beta-(5-indolyl)-8-azabicyclo[3.2.1]octanes display potent binding affinity for both the dopamine and serotonin transporters, while certain 3beta-(4-(2-pyrrolyl)phenyl)-8-azabicyclo[3.2.1]octanes selectively bind to the serotonin transporter. 相似文献
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J Cambar C Toussaint C Nguyen Ba 《Comptes rendus des séances de la Société de biologie et de ses filiales》1978,172(1):103-109
Circadian rhythms in urinary water, sodium, potassium and proteins excretion are studied in 45 rats living alone in metabolism cages. Urines are collected during 4 consecutive 6 hours long periods during 2 consecutive days. Large circadian variations of these parameters (especially water and proteins excretion and urinary protein concentration) are described. The influence of feeding rhythms on the circadian urinary excretion rhythms is discussed. It is proposed that nightly renal hemodynamic changes (during meal digestion or with high renin plasma levels) can induce modifications in glomerular filtration rate and electrolytes and macromolecules transglomerular flow. 相似文献
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The 3'phosphoramidite of 8-histaminyl deoxyadenosine has been prepared and successfully incorporated into a short oligodeoxyribonucleotide. The synthetic methodology leading to this preparation is given and the implications for developing new DNAzymes as well as probing unusual nucleic acid structures are discussed. 相似文献
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Steven L. Goldberg Venkata B. Nanduri Linda Chu Robert M. Johnston Ramesh N. Patel 《Enzyme and microbial technology》2006,39(7):1441-1450
The enantioselective microbial reduction of 6-oxo-8-[4-[4-(2-pyrimidinyl)-1-piperazinyl]butyl]-8-azaspiro[4.5]decane-7,9-dione (1) to either of the corresponding (S)- and (R)-6-hydroxy-8-[4-[4-(2-pyrimidinyl)-1-piperazinyl]butyl]-8-azaspiro[4.5]decane-7,9-diones (2 and 3, respectively) is described. The NADP+-dependent (R)-reductase (RHBR) which catalyzes the reduction of 6-ketobuspirone (1) to (R)-6-hydroxybuspirone (3) was purified to homogeneity from cell extracts of Hansenula polymorpha SC 13845. The subunit molecular weight of the enzyme is 35,000 kDa based on sodium dodecyl sulfate gel electrophoresis and the molecular weight of the enzyme is 37,000 kDa as estimated by gel filtration chromatography. (R)-reductase from H. polymorpha was cloned and expressed in Escherichia coli. To regenerate the cofactor NADPH required for reduction we have cloned and expressed the glucose-6-phosphate dehydrogenase gene from Saccharomyces cerevisiae in E. coli. The NAD+-dependent (S)-reductase (SHBR) which catalyzes the reduction of 6-ketobuspirone (1) to (S)-6-hydroxybuspirone (2) was purified to homogeneity from cell extracts of Pseudomonas putida SC 16269. The subunit molecular weight of the enzyme is 25,000 kDa based on sodium dodecyl sulfate gel electrophoresis. The (S)-reductase from P. putida was cloned and expressed in E. coli. To regenerate the cofactor NADH required for reduction we have cloned and expressed the formate dehydrogenase gene from Pichia pastoris in E. coli. Recombinant E. coli expressing (S)-reductase and (R)-reductase catalyzed the reduction of 1 to (S)-6-hyroxybuspirone (2) and (R)-6-hyroxybuspirone (3), respectively, in >98% yield and >99.9% e.e. 相似文献
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Steroid metabolism in the cat. Biliary and urinary excretion of metabolites of [4-14C]cortisone
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W. Taylor 《The Biochemical journal》1969,113(2):259-261
1. [4-(14)C]Cortisone was administered to anaesthetized male cats as a single injection or as a 45-60min. infusion. 2. After the single dose a total of 69.6-89.6% of the radioactivity was excreted in bile, and 0.5-7.1% in urine. After infusion total recovery in bile was 73.4-92.1%, and 1.2-1.7% in urine. 3. When bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid, most of the radioactivity was converted into substances not extractable from neutral aqueous solution by ethyl acetate-ether. 4. In bile, metabolites hydrolysable by beta-glucuronidase were found in only small proportions (3-4%) of the dose. 相似文献
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Steroid metabolism in the cat. Biliary and urinary excretion of metabolites of [4-14C]oestradiol
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1. [4-14C]Oestradiol was administered to seven male, seven female and two castrated male cats as a single intravenous injection. Bile and urine were collected for 6h. 2. The radioactivity was excreted mainly in the bile of all animals (53–60%); only approx. 1% of the dose appeared in the urine. 3. Bile and urine samples were hydrolysed successively by β-glucuronidase, cold acid and hot acid. There were significant differences (P<0.005) between the percentage of the dose present in the bile fractions hydrolysed by β-glucuronidase (male, 9.0±1.7%; female, 18.6±1.45%) and by cold acid (male, 18.9±1.44%; female 12.1±1.02%). The excretion of radioactivity in these fractions by the castrated male cats was closer to that of female cats. 4. Approx. 20–27% of the dose could not be extracted from aqueous solution (pH10.5) by ethyl acetate–ether after hydrolysis. 相似文献
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1. [4-(14)C]Testosterone was administered intravenously to anaesthetized male cats as a single injection or as a 45-60min. infusion. 2. Most of the administered radioactivity was excreted in the bile (70-80%); only 2.9-5.5% of the dose was excreted in the urine. 3. Bile and urine samples were hydrolysed successively to yield glucuronide, ;cold-acid-hydrolysed' and ;hot-acid-hydrolysed' fractions. 4. The proportion of glucuronides in bile decreased in successive samples, but cold-and hot-acid-hydrolysed metabolites showed no consistent change. 5. After hydrolysis most of the radioactivity in both bile and urine could not be extracted by ether from neutral aqueous solution. 相似文献
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Steroid metabolism in the rabbit. Biliary and urinary excretion of metabolites of [4-14C]progesterone
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1. [4-(14)C]Progesterone was administered intravenously to anaesthetized male and female New Zealand White rabbits as a single injection or as a 45-60min. infusion. 2. After a single dose about 60% of the radioactivity was recovered in 6hr., and twice as much radioactivity was present in bile as in urine. After infusion total recovery of radioactivity was only about 40% in 6hr., but the relative proportions of metabolites in bile and urine were about the same as after a single dose. 3. Bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid. 4. In bile the major proportion of metabolites appeared in the glucuronide fraction; in urine beta-glucuronidase hydrolysis yielded the greatest amounts of ether-extractable radioactivity, but the greatest proportion of radioactivity could not be extracted by ether from an alkaline solution of the hydrolysed urine. 5. There was no apparent difference in the quantity or distribution of metabolites excreted by male and female animals. 相似文献
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1. [4-(14)C]Testosterone was administered to anaesthetized male and female New Zealand White rabbits as a single injection or as a 45-60min. infusion. 2. After a single dose a total of approx. 56-80% of the radioactivity was excreted in bile and urine. After infusion total recovery of radioactivity was approx. 63-75%. 3. The mean ratio of metabolites in urine to those in bile was 0.77+/-0.41 (range 0.3-1.5). 4. Bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid. In both bile and urine neutral metabolites extracted by ethyl acetate-ether were found mainly after beta-glucuronidase hydrolysis, but a considerable proportion of the dose was converted into substances not extractable from alkaline aqueous solution after all forms of hydrolysis used. 相似文献
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Steroid metabolism in the rabbit. Biliary and urinary excretion of metabolites of [4-14C]cortisone 总被引:1,自引:2,他引:1
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W. Taylor 《The Biochemical journal》1970,117(2):263-265
1. [4-(14)C]Cortisone was administered to anaesthetized male and female New Zealand White rabbits as a single injection or as a 45-60min infusion. 2. The method of administration of the steroid did not significantly affect the total excretion of radioactivity in bile and urine [83.8+/-10.8%(s.d.)]. 3. The mean ratio of metabolites in urine to those in bile was 0.97+/-0.23% (range 0.64-1.3). 4. When bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid, neutral metabolites extracted by ethyl acetate-ether were found mainly after hydrolysis by beta-glucuronidase. 5. An approximately equal proportion of the dose was converted into substances not extractable from alkaline aqueous solution after hydrolysis. 相似文献
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Longitudinal study of urinary 8-hydroxy-2'-deoxyguanosine excretion in healthy adults 总被引:7,自引:0,他引:7
Alexander Pilger Dietmar Germadnik Kirsten Riedel Irmtrud Meger-Kossien Gerhard Scherer Hugo W. Rü diger 《Free radical research》2001,35(3):273-280
Numerous studies have investigated the urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker for the assessment of oxidative DNA damage in humans. In this study, we performed six consecutive series of measurement of urinary levels of 8-OHdG in 68 healthy probands, in order to provide information on the intra- and inter-individual variability of 8-OHdG and to estimate the influence of smoking, age, sex, body weight and body mass index (BMI) on the excretion of 8-OHdG. The intraindividual coefficient of variation (CV) of urinary 8-OHdG/24h ranged from 0.18 to 1.06 (mean CV=0.48). Women excreted significantly lower amounts of 8-OHdG/24h than men, but the difference lost its significance when the body weight or urinary creatinine were used as covariates. By multiple linear regression analysis significant correlations between the mean individual levels of 8-OHdG/24h excretion and urinary creatinine (rp = 0.61), and cotinine (rp = 0.27) have been observed, whereas no statistically significant effect of age, body weight and BMI was found. The 8-OHdG/creatinine ratio was found to be significantly increased in 23 smokers (1.95 ± 0.40 μmol/mol) opposed to 45 non-smoking probands (1.62 ± 0.50 μmol/mol), which is in good agreement with previously published data. No effect of passive smoking on the excretion of 8-OHdG was found. From our data we conclude that the intraindividual variability of urinary 8-OHdG excretion has been underestimated so far, indicating that values of 8-OHdG measured by single spot monitoring are not representative for individual base levels. 相似文献
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Oguogho A Ferlitsch A Sinzinger H 《Prostaglandins, leukotrienes, and essential fatty acids》2000,62(4):209-216
Isoprostanes (IP) generated during free radical catalyzed oxidation injury have been claimed as a reliable indicator of oxidative stress in vivo. In particular, they are formed during LDL-oxidation. Vascular content, plasma levels and urinary excretion of IP were reported to be elevated in hypercholesterolemia. We therefore assessed the values of the IP 8-epi-PGF2alpha in plasma and urine in nine patients (7 males, 2 females) suffering from severe heterozygous hypercholesterolemia before and after LDL-apheresis as well as during the interval. LDL-apheresis caused a significant (P<0.01) drop in 8-epi-PGF2alpha in plasma and urine. The respective values in smokers (n = 4) were significantly (P<0.01) higher as compared to non-smokers. No sex difference was seen. Together with the findings of a parallel decrease in oxidized LDL, these data show a significant benefit of LDL-apheresis reducing in vivo oxidation injury. This benefit may at least partly contribute to the clinical improvement seen in the patients treated. 相似文献