共查询到20条相似文献,搜索用时 15 毫秒
1.
G. Casademont B. Pérez J.A. García Regueiro 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,686(2):258
A method to determine twelve anabolic hormones (diethylstilbestrol, hexestrol, dienestrol, 17β-estradiol, 19-nortestosterone, testosterone, 1-dehydrotestosterone, 17α-methyltestosterone, progesterone, estrone, 17α-ethynilestradiol, and trenbolone) is presented. Urine samples were extracted with octadecylsilica columns and clean-up was performed in two steps with basic alumina and silica solid-phase extraction cartridges. The extracts obtained were derivatized with heptafluorobutyric anhydride and analyzed by GC-MS. Stability of derivatives was good and compounds having keto groups produced enol derivatives that were stable also. SIM mode was applied to increase the sensitivity and, when possible, the higher m/z ions were selected to improve identification. Repeatability of the chromatographic analysis was evaluated on the basis of area repeatability, and the coefficient of variation obtained was lower than 13%. Absolute recoveries were in the range 35–60% (dehydrotestosterone and estrone <20%) with coefficients of variation between 14 and 37% for the whole procedure. [2H3]Testosterone and [2H8]diethylstilbestrol were evaluated to improve quantitative data. The recovery of [2H3]testosterone was found to be equal to or slightly higher than that of the other hormones, but the recovery of [2H8]diethylstilbestrol was lower than any other. [2H3]Testosterone was the most suitable for use as an internal standard, as its addition at the beginning of analytical procedure, corrected recovery results and greatly improved precision. Corrected recoveries from urine ranged from 72–110%, and coefficients of variation ranged from 6–15%, except for testosterone which yielded slightly higher values. The limit of detection was 0.5 ng/ml for all the compounds studied. 相似文献
2.
Takehisa Matsukawa Hiroshi Hasegawa Yoshihiko Shinohara Takao Hashimoto 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,751(2)
A method for determination of α-ketoisocaproic acid (KIC) and [4,5,5,5,6,6,6-2H7]α-ketoisocaproic acid ([2H7]KIC) in rat plasma was developed using gas chromatography–mass spectrometry-selected ion monitoring (GC–MS-SIM). [5,5,5-2H3]α-Ketoisocaproic acid ([2H3]KIC) was used as an analytical internal standard to account for losses associated with the extraction, derivatization and chromatography. The keto acids were extracted by cation-exchange chromatography using BondElut SCX cartridge and derivatized with N-phenyl-1,2-phenylenediamine to form N-phenylquinoxalinone derivatives. Quantitation was performed by SIM of the respective molecular ions at m/z 278, 281 and 285 for the derivatives of KIC, [2H3]KIC and [2H7]KIC on the electron impact method. The limit of detection was found to be 70 fmol per injection (S/N=3) and the limit of quantitation for [2H7]KIC was around 50 nM in rat plasma. Endogenous KIC concentrations in 50 μl of rat plasma were measured with relative intra- and inter-day precision of 4.0% and 3.3%, respectively. The intra- and inter-day precision for [2H7]KIC spiked to rat plasma in the range of 0.1 to 10 μM gave good reproducibility with relative standard deviation (RSD) of 6.5% and 5.4%, respectively. The intra- and inter-day relative errors (RE) for [2H7]KIC were less than 6.4% and 3.8%, respectively. The method was applied to determine the plasma concentration of [2H7]KIC after an intravenous administration of [2H7]KIC in rat. 相似文献
3.
Takashi Furuta Toshiyuki Namekawa Hiromi Shibasaki Yasuji Kasuya 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,706(2):328
A capillary gas chromatographic–mass spectrometric method for the simultaneous determination of tetrahydrocortisol (THF, 3α,11β,17α,21-tetrahydroxy-5β-pregnane-20-one), allo-tetrahydrocortisol (allo-THF, 3α,11β,17α,21-tetrahydroxy-5α-pregnane-20-one) and tetrahydrocortisone (THE, 3α,17α,21-trihydroxy-5β-pregnane-11,20-dione) in human plasma and urine is described. [1,2,3,4,5-2H5]THF (THF-d5), allo-[1,2,3,4,5-2H5]THF (allo-THF-d5) and [1,2,3,4,5-2H5]THE (THE-d5) were used as internal standards. A double derivatization (bismethylenedioxypentafluoropropionate, BMD-PFP) made possible the separation of the three tetrahydrocorticoids with good gas chromatographic behavior. Quantitation was carried out by selected-ion monitoring of the characteristic fragment ions ([M−30]+) of the BMD-PFP derivatives of THF, allo-THF and THE. The sensitivity, specificity, precision and accuracy of the method were demonstrated to be satisfactory for measuring low concentrations of THF, allo-THF and THE in human plasma and urine. 相似文献
4.
Takashi Furuta Mitsuhiro Matsuzawa Hiromi Shibasaki Yasuji Kasuya 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,738(2)
A capillary gas chromatographic–mass spectrometric method for the simultaneous determination of 6β-hydroxycortisol (6β-OHF, 6β,11β,17α,21-tetrahydroxypregn-4-ene-3,20-dione), 6α-hydroxycortisol (6α-OHF, 6α,11β,17α,21-tetrahydroxypregn-4-ene-3,20-dione) and 6β-hydroxycortisone (6β-OHE, 6β,17α,21-trihydroxypregn-4-ene-3,11,20-trione) in human urine is described. Deuterium-labelled compounds, 6β-[1,1,19,19,19-2H5]OHF (6β-OHF-d5), 6α-[1,1,19,19,19-2H5]OHF (6α-OHF-d5) and 6β-[1,1,19,19,19-2H5]OHE (6β-OHE-d5) were used as internal standards. Quantitation was carried out by selected-ion monitoring of the characteristic fragment ions ([M-31]+) of the methoxime–trimethylsilyl (MO–TMS) derivatives of 6β-OHF, 6α-OHF and 6β-OHE. The sensitivity, specificity, precision and accuracy of the method were demonstrated to be satisfactory for measuring 6β-OHF, 6α-OHF and 6β-OHE in human urine. 相似文献
5.
Yoshihiko Shinohara Koichiro Isurugi Takao Hashimoto 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,741(2):1401
A method based on gas chromatography–mass spectrometry–selected-ion monitoring was developed to measure the main metabolites of 17α-methyltestosterone, 17α-methyl-5α-androstan-3α,17β-diol and 17α-methyl-5β-androstan-3α,17β-diol, in human urine. 17α-Methyl-[2H3]-5α-androstan-3α,17β-diol and 17α-methyl-[2H3]-5β-androstan-3α,17β-diol were used as internal standards. The methods involved purification using a Sep-Pak C18 cartridge, hydrolysis by β-glucuronidase from Ampullaria and derivatization with N-methyl-N-trimethylsilyl-trifluoroacetamide/dithioerythriol/ammonium iodide. Quantitation was achieved by selected-ion monitoring of the characteristic fragment ions ([(M+H)−2×TMSOH]+) of the di-TMS derivatives on the chemical ionization mode. The method provides a specific, sensitive and reliable technique to determine the urine levels of 17α-methyl-5α-androstan-3α,17β-diol and 17α-methyl-5β-androstan-3α,17β-diol, and can be applied to pharmacokinetic studies of 17α-methyltestosterone. 相似文献
6.
Gabriele Sabbioni Armin Beyerbach 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,744(2):1
Aromatic amines and nitroarenes are important antioxidants and intermediates in the synthesis of dyes, pesticides and plastics. In the present paper we introduce methods for the synthesis of deuterated standards: 3-[2H8]aminofluoranthene, 3,3′-dimethyl-[2H4]benzidine, [2H4]benzidine, N′-acetyl-[2H4]benzidine, 2,4-[2H6]toluenediamine, 2,6-[2H6]toluenediamine. These standards have been used for the quantification of haemoglobin adducts of diamines and polyaromatic amines. Haemoglobin was hydrolysed in 0.1 M sodium hydroxide and the hydrolysate extracted with dichloromethane. The extracts were derivatised with heptafluorobutyric anhydride and analysed by GC–MS with negative chemical ionisation. In one run up to 15 aromatic amines can be determined: 6-aminochrysene, 3-aminofluoranthene, 2-aminofluorene, 1-aminopyrene, benzidine, 3,3′-dichlorobenzidine, 3,3′-dimethoxybenzidine, 3,3′-dimethylbenzidine, 3,3′-methylenedianiline, 4,4′-methylenedianiline, N′-acetyl-benzidine, N′-acetyl-4,4′-methylenedianiline, 4,4′-methylene bis(2-chloroaniline), 2,4-toluenediamine and 2,6-toluenediamine. 相似文献
7.
Yan Feng Baoying Wang Fangying Du Hongbo Li Shaolan Wang Chenghu Hu Chunhui Zhu Xiaorui Yu 《PloS one》2013,8(11)
Intracellular calcium concentration ([Ca2+]i) plays an important role in regulating most cellular processes, including apoptosis and survival, but its alterations are different and complicated under diverse conditions. In this study, we focused on the [Ca2+]i and its control mechanisms in process of hydrogen peroxide (H2O2)-induced apoptosis of primary cultured Sprague-Dawley (SD) rat retinal cells and 17β-estradiol (βE2) anti-apoptosis. Fluo-3AM was used as a Ca2+ indicator to detect [Ca2+]i through fluorescence-activated cell sorting (FACS), cell viability was assayed using MTT assay, and apoptosis was marked by Hoechst 33342 and annexin V/Propidium Iodide staining. Besides, PI3K activity was detected by Western blotting. Results showed: a) 100 μM H2O2-induced retinal cell apoptosis occurred at 4 h after H2O2 stress and increased in a time-dependent manner, but [Ca2+]i increased earlier at 2 h, sustained to 12 h, and then recovered at 24 h after H2O2 stress; b) 10 μM βE2 treatment for 0.5-24 hrs increased cell viability by transiently increasing [Ca2+]i, which appeared only at 0.5 h after βE2 application; c) increased [Ca2+]i under 100 µM H2O2 treatment for 2 hrs or 10 µM βE2 treatment for 0.5 hrs was, at least partly, due to extracellular Ca2+ stores; d) importantly, the transiently increased [Ca2+]i induced by 10 µM βE2 treatment for 0.5 hrs was mediated by the phosphatidylinositol-3-kinase (PI3K) and gated by the L-type voltage-gated Ca2+ channels (L-VGCC), but the increased [Ca2+]i induced by 100 µM H2O2 treatment for 2 hrs was not affected; and e) pretreatment with 10 µM βE2 for 0.5 hrs effectively protected retinal cells from apoptosis induced by 100 µM H2O2, which was also associated with its transient [Ca2+]i increase through L-VGCC and PI3K pathway. These findings will lead to better understanding of the mechanisms of βE2-mediated retinal protection and to exploration of the novel therapeutic strategies for retina degeneration. 相似文献
8.
Sandra A. Swartz Melvyn S. Soloff J.Robert Suriano 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,338(2):480-488
Amniotic fluid from 15–17-day rat fetuses bound estrone and 17β-estradiol specifically. Related steroids such as estriol, 6-ketoestradiol, 17α-estradiol and testosterone were not bound to any significant extent. The apparent Ka for 17β-estradiol was 2.6·108 M− at 4°C; 6 nmoles of 17β-estradiol were bound per ml of amniotic fluid. The binding component appears to be α-fetoprotein in that it migrates as an α1-globulin upon polyacrylamide gel electrophoresis and has an isoelectric pH of 4.7 as determined by isoelectric focusing. Furthermore, binding activity was precipitated by antiserum which was shown by immuno-electrophoresis to be specific for α-fetoprotein. Binding activity, partially purified by isoelectric focusing of amniotic fluid, was associated with one of two bands seen by polyacrylamide gel electrophoresis. This band migrated as an α1-globulin. 相似文献
9.
Ch. V. Rao 《Prostaglandins & other lipid mediators》1975,9(4):579-584
The specific binding of 3H-prostaglandin E1 (3H-PGE1) to bovine corpus luteum cell membranes was not affected by cholesterol or various progestins at concentrations of up to 9.0 × 10−6M. At concentrations above 2.5 × 10−6M; estrone, 17β-estradiol (but not 17α-estradiol or 17β-estradiol glucuronide), estriol, equilin, D-equilenin, 17-ethynyl estradiol, diethylstilbestrol, cortisol, corticosterone, deoxycorticosterone and aldosterone inhibited specific binding of 3H-PGE1. On the other hand, testosterone and dihydrotestosterone (DHT) (but not androstenedione) significantly enhanced 3H-PGE1 binding. These findings permitted the following correlations between steroid structure and modulation of 3H-PGE1 binding: steroids with a free phenolic ring and a 17β-hydroxyl or 17-keto group or C-21 steroids with a C-20 ketone and a C-21 hydroxy group decrease, whereas C-19 steroids with a C-17 hydroxy group enhance specific binding of 3H-PGE1. PGE receptors are heterogeneous with respect to affinity for 3H-PGE1. The steroids that decreased 3H-PGE1 binding caused a lowering to a complete loss of low affinity PGE receptors. Steroids that increased 3H-PGE1 binding caused appearance of new low affinity PGE receptors. Association rate constants for 3H-PGE1 binding were decreased by 17β-estradiol (61%) and increased by DHT (59%). 相似文献
10.
F.F. Sun B.M. Taylor D.M. Sutter J.R. Weeks 《Prostaglandins & other lipid mediators》1979,17(5):753-759
The in vivo metabolism of 6-keto PGF1α was investigated in rats. Following continuous intravenous infusion for 14 days the urinary metabolites were isolated and identified. A substantial amount of unchanged 6-keto PGF1α was recovered in the urine. The metabolic pattern very closely resembles that of PGI2 in rats. Metabolites were found which represented 15-dehydrogenation, β-oxidation, ω and ω-1-hydroxylation and oxidation.Previous work showed that 6-keto PGF1α is very poorly oxidized by 15-PGDH. We administered 15-[H3]-PGI2 and 15-[H3]-6-keto PGF1α to rats and measured urinary tritiated water as an index for in vivo 15-PGDH activity. The results showed that PGI2 and 6-keto PGF1α were both oxidized to the 15-keto product, although the rate of oxidation of PGI2 was greater than that of 6-keto PGF1α. We concluded that the administered PGI2 was oxidized by 15-PGDH before hydrolysis to 6-keto PGF1α. A portion of the dose is probably hydrolyzed before 15-dehydrogenation. 相似文献
11.
《Steroids》1982,39(6):667-673
The synthesis of [2H8]estradiol, [2H7]estrone, [2H6]2-hydroxyestrone and [2H6]4-hydroxyestrone from estrone (as a source) is described. The high isotopical purity renders the labelled compounds as suitable carriers and internal standards for quantitative gas chromatography — mass spectrometry. The content of protonium-form (i.e. natural) estrogens in the labelled derivatives ranged from 0.12 % to 2.58 %. The perfcrmance of these compounds in quantitative assays using selected ion monitoring has been established; and this allows the determination of estrogens from biological material in the lower picogram range. 相似文献
12.
Biosynthesis of 20-hydroxyecdysone in Ajuga hairy roots: fate of 6α- and 6β-hydrogens of lathosterol
Kiyoshi Ohyama Tetsuo Kushiro Kinya Nakamura Yoshinori Fujimoto 《Bioorganic & medicinal chemistry》1999,7(12):2226
The fate of 6α- and 6β-hydrogens of lathosterol during the transformation into 20-hydroxyecdysone was chased by feeding [3α,6β-2H2]- and [3α,6α-2H2]-lathosterols to hairy roots of Ajuga reptans var. atropurpurea. The behavior of 6β-hydrogen, which mostly migrated to the C-5 position of 20-hydroxyecdysone, was in agreement with that of C-6 hydrogen of cholesterol. The results strongly supported the view that cholesterol and lathosterol are first metabolized into 7-dehydrocholesterol, which is then converted into 20-hydroxyecdysone via 7-dehydrocholesterol 5α,6α-epoxide in the hairy roots. 相似文献
13.
B. Rao 《Prostaglandins & other lipid mediators》1979,18(1):93-100
In vitro synthesis of progesterone and estradiol-17β from endogenous precursors was studied in the placenta from women in early stage of gestation (< 7 weeks). Radioimmunoassay techniques were used to measure progesterone and estradiol-17β.It was shown that placental tissue from as early as six weeks of gestation can synthesize both progesterone and estradiol-17β in vitro. Prostaglandins F2α and E2 in concentration of 100 μg/ml of the incubation media did not have any significant effect on the in vitro synthesis of progesterone and estradiol-17β in the placental tissue.It seems unlikely that the abortifacient effect of natural prostaglandins PGE2 and PGF2α is due to their direct action on the synthesis of progesterone and estradiol-17β in the placenta. 相似文献
14.
Fluorescence measurement of intracellular sodium concentration in single Escherichia coli cells
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The energy-transducing cytoplasmic membrane of bacteria contains pumps and antiports maintaining the membrane potential and ion gradients. We have developed a method for rapid, single-cell measurement of the internal sodium concentration ([Na+]in) in Escherichia coli using the sodium ion fluorescence indicator, Sodium Green. The bacterial flagellar motor is a molecular machine that couples the transmembrane flow of ions, either protons (H+) or sodium ions (Na+), to flagellar rotation. We used an E. coli strain containing a chimeric flagellar motor with H+- and Na+-driven components that functions as a sodium motor. Changing external sodium concentration ([Na+]ex) in the range 1–85 mM resulted in changes in [Na+]in between 5–14 mM, indicating a partial homeostasis of internal sodium concentration. There were significant intercell variations in the relationship between [Na+]in and [Na+]ex, and the internal sodium concentration in cells not expressing chimeric flagellar motors was 2–3 times lower, indicating that the sodium flux through these motors is a significant fraction of the total sodium flux into the cell. 相似文献
15.
The metabolism of estradiol-17β by the guinea pig uterus late in pregnancy was studied and .Whole uteri were examined for estrogen metabolites one hour following an intravenous injection of [3H]-estradiol-17β or uterine sections were examined after incubation for one hour at 37°C in medium containing [3H]-estradiol-17β.In both instances uterine tissue metabolized estradiol-17g to five products: estrone, estrone-3-sulfate, 17β-estradiol-3-sulfate, estrone-3-glucuronide and 17β-estradiol-3-glucuronide. Of the total radioactive products 11 – 43% were glucuronides, 17 – 26% were sulfates and 4 – 17% was estrone. These results indicate that the guinea pig uterus actively transforms estradiol-17β into glucuronides and sulfates late in pregnancy. 相似文献
16.
Estrone glucosiduronate, 17β-estradiol-3-glucoslduronate, 17β-estradiol-17-glucosiduronate and estriol-16α-glucoslduronate have been biosynthesized in substantial yield by incubation of radioactive estrone, 17β-estradiol, estriol and uridlne diphosphoglucosiduronic acid with rhesus monkey liver homogenates. The metabolites were characterized by chromatography on Celite and DEAE-Sephadex, enzyme hydrolysis, derivative formation and crystallization to constant specific activity. The percent conversion to 17β-estradiol-17-glucosiduronate from 17β-estradlol ranged between 56–71%; from estrone, the conversion was 49–54%. Other metabolites formed from estradiol were estrone glucosiduronate(12–21%) and 17β-estradiol-3-glucosiduronate(5–12%). The same metabolites derived from estrone accounted for 18–28% and 10–14% respectively. After estriol incubation, more than 90% of the steroid was converted to estriol-16α-glucosiduronate with no detectable estriol-3-glucosiduronate. This report represents the first time that 17β-estradiol-17-glucosiduronate has been reported as a metabolite in the rhesus monkey and this is the only known species which forms 17β-estradiol-17-glucosiduronate as the predominant metabolite of either estrone or estradiol .Rhesus monkey liver is similar to the human and baboon in that it metabolizes estriol exclusively to estriol-16-glucosiduronate. 相似文献
17.
Francesco Bigoli Maurizio Lanfranchi Maria Angela Pellinghelli 《Inorganica chimica acta》1984,90(3):215-220
The structures of bis(1H+,5H+-S-methylisothiocarbonohydrazidium) di-μ-chlorooctachlorodibismuthate(III) tetrahydrate: (C2H10N4S)2(Bi2Cl10)· 4H2O (compound [I]) and of tris(1H+-S-methylisothiocarbonohydrazidium) esachlorobismuthate(III): (C2H9N4S)3(BiCl5.67I0.33) (compound [II]) were determined from single crystal X-ray diffractometer data. Both compounds crystallize as triclinic (P
); crystals [I] with Z = 1 formula unit in a cell of constants: A = 10.621(3), B = 9.989(5), C = 7.439(3) Å, α = 88.31(2), β = 84.51(2), γ = 68.88(2)°, final R = 0.0427 for 2229 unique reflections with I 2σ(I); crystals [II] with Z = 2 and cell dimensions: A = 14.109(4), B = 12.209(9), C = 8.206(7) Å, α = 103.54(3), β = 104.95(2), γ = 81.96(2)°, final R = 0.0411 for 3637 unique reflections (1 2σ(I)). The structure of [I] is built up of diprotonated organic cations, water molecules and dinuclear centrosymmetric [Bi2Cl10]4− anions held together by N-HCl, N-HO, O-HCl hydrogen bonds and Van der Waals interactions. The [Bi2Cl10]4− complex consists of two edge-sharing octahedra in which three pairs of bonds of similar length are observed (Bi-Clav = 2.602(5), 2.712(4), 2.855(5) Å). The structure of [II] consists of monoprotonated cations and [BiCl5.67I0.33]3− anions held together by a tridimensional network of hydrogen bonds. Each bismuth atom is octahedrally surrounded by six chlorine atoms, one of which is statistically substituted by a iodine atom. 相似文献
18.
3H-Estrone and H-estradiol-17β were infused in separate experiments into the jugular veins of each of 4 ewes. During the infusions blood samples were obtained from the ipsilateral jugular vein and common carotid artery. The blood samples were analyzed for radioactivity as free estrone and estradiol-17β and the conversion of infused precursor to product steroid by brain tissue, the transtissue conversion (ρPRE-PROAV) and the extraction by brain tissue of infused precursor, the transtissue extraction (1-ρPRE-PREAV) and the metabolic clearance rates were calculated.The mean ± SE for ρAV1,2 (precursor, estrone = 1; product, estradiol = 2) was 0.09 ±0.03 and the mean ± SE for ρAV2,1 (precursor, estradiol = 2; product, estrone = 1) was 0.08 ±0.02. The mean trans-tissue extraction of estrone was 0.13 ± 0.02 and of estradiol-17β was 0.14- ± 0.02. The transtissue extractions of estrone and estradiol-17β were greater than ρAV1,2 ρAV2,1 respectively in 2 of the 4 ewes.Brain metabolism of estrogens can account for only 2–4% of the total metabolism of these free estrogens from the blood pool. 相似文献
19.
New hydrogen-bonding assemblies were synthesized from the reaction of a metalloligand, [Cu(2,4-pydca)2]2− (LCu) (2,4-pydca = 2,4-pyridinedicarboxylate), with a FeII ion or an imidazole in an aqueous medium and crystallographically characterized. The obtained compounds, [Fe(H2O)6][Cu(2,4-pydca)2] (1) and [Cu(2,4-pydca)(imidazole)2] · 2H2O (2), have metalloligand dimer units, [Cu2(2,4-pydca)4]4− and [Cu2(2,4-pydca)2(imidazole)4], respectively, each of which assembles by π-π (1) and hydrogen-bonding (2) interactions to form 1-D metalloligand arrays. The 1-D metalloligand arrays are linked by rich hydrogen-bonding interactions via H2O molecules. 相似文献
20.
《Journal of steroid biochemistry》1976,7(8):605-609
Androstenedione, estrone, estradiol-17β, estriol and testosterone concentrations have been measured by radioimmunoassay in plasma of 17 human males affected by breast cancer. The mean values of estrone, estradiol-17β, and estriol in male breast cancer were significantly higher than in normal controls of comparable age. Androstendione and testosterone were in normal range.Orchidectomy. performed in 3 subjects, decreased the levels of estradiol-17β, but to a lesser extent those of estrone and estriol. 相似文献