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1.
Neuroscience ; 169(4): 1860-71, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20600634

ABSTRACT

The present study investigated the precise relationship between brain biogenic amine (dopamine, noradrenaline, and serotonin) tones and nociception. Nociceptive sensitivities to multimodal (muscle pressure, tactile, cold, and heat) stimuli were assessed in acute phase (up to 24 h after reserpine or tetrabenazine injection) and chronic phase (on day 2 or later) in rats. A single injection of reserpine (3 mg/kg s.c.) significantly decreased biogenic amines in the spinal cord (SC), thalamus (THA), and prefrontal cortex (PFC) in both acute and chronic phases, but significantly increased a dopamine metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) in the SC and a serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the SC and THA in acute phase. The content of all biogenic amine metabolites was at low level in chronic phase. Animals exhibited hypersensitivities to tactile and heat stimuli and hyposensitivity to muscle pressure stimulus in acute phase. In chronic phase, they manifested hypersensitivities to all modes of stimuli. Tetrabenazine (20 mg/kg i.p.) significantly decreased brain biogenic amines for a short time, although it did not significantly affect the nociceptive sensitivities. In conclusion, a single injection of reserpine causes a biphasic alteration of nociceptive sensitivities, which is in conjunction with the dynamic change of brain biogenic amine tones, in rats. Cold and heat hypersensitivities in addition to mechanical ones are induced by the reserpine treatment. Sustained modification of brain biogenic amine tones would be critical to induce a robust change in nociceptive sensitivities based on the different effects between reserpine and tetrabenazine.


Subject(s)
Biogenic Amines/metabolism , Brain/drug effects , Brain/metabolism , Nociceptors/drug effects , Pain Threshold/drug effects , Reserpine/pharmacology , Adrenergic Uptake Inhibitors/pharmacology , Animals , Hot Temperature/adverse effects , Male , Nociceptors/physiology , Pain Threshold/physiology , Physical Stimulation/adverse effects , Rats , Rats, Sprague-Dawley
2.
Kekkaku ; 76(5): 427-36, 2001 May.
Article in Japanese | MEDLINE | ID: mdl-11449698

ABSTRACT

Short course regimens; 2HRZ (E)(S)/4HR (E), 6HRS (E)/3-6HR and 6-9HR have been accepted as a standard chemotherapy (SC) for initial treatment of pulmonary tuberculosis in Japan. We studied the frequency of the treatment completion, the causes of the treatment failure and the outcome of the patients in whom INH or RFP was discontinued within 6 months after starting SC. The subjects included 597 newly diagnosed culture positive pulmonary tuberculosis patients admitted to 16 national hospital in 1996. Results were as follows. 1. In 47 (7.9%) of the 597 patients, either INH (19; 3.2%) or RFP (33; 5.5%) was discontinued. These 47 cases were defined as a SC incompleted group and the other 550 as a SC completed group. 2. The patients in the SC incompleted group were seen more frequently in the ages of 20s (11.9%), 50s (10.9%), 60s (11.7%) or 70s (11.4%). 21 (13.6%) of 154 female patients and 26 (5.9%) of 443 male patients were in the SC incompleted group. 3. The causes of cessation of INH or RFP were drug side effects (33; 5.5%), drug resistance (10; 1.7%) and complications or underlying diseases (8; 1.3%). 4. Fever or eruption (19; 3.2%) and drug induced hepatitis (12; 2.0%) were frequently seen as drug related side effects causing the cessation of INH or RFP. 5. The rate of culture negative conversion of TB bacilli at 6 months after the start of the treatment was 98.9% in the SC completed and 88.9% in the SC incompleted group respectively. In the SC incompleted group, there were three cases continuously positive and two other patients who relapsed and became culture positive again. In these five patients, INH or RFP was discontinued because of drug resistance.


Subject(s)
Antibiotics, Antitubercular/administration & dosage , Antitubercular Agents/administration & dosage , Isoniazid/administration & dosage , Rifampin/administration & dosage , Tuberculosis, Multidrug-Resistant , Tuberculosis, Pulmonary/drug therapy , Adolescent , Adult , Aged , Antibiotics, Antitubercular/adverse effects , Antitubercular Agents/adverse effects , Chemical and Drug Induced Liver Injury , Drug Eruptions/etiology , Female , Fever/chemically induced , Humans , Isoniazid/adverse effects , Male , Middle Aged , Rifampin/adverse effects , Sex Factors
3.
Science ; 292(5524): 2083-6, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11408659

ABSTRACT

Epidemiological data suggest that dietary antioxidants play a protective role against cancer. This has led to the proposal that dietary supplementation with antioxidants such as vitamin C (vit C) may be useful in disease prevention. However, vit C has proved to be ineffective in cancer chemoprevention studies. In addition, concerns have been raised over potentially deleterious transition metal ion-mediated pro-oxidant effects. We have now determined that vit C induces lipid hydroperoxide decomposition to the DNA-reactive bifunctional electrophiles 4-oxo-2-nonenal, 4,5-epoxy-2(E)-decenal, and 4-hydroxy-2-nonenal. The compound 4,5-Epoxy-2(E)-decenal is a precursor of etheno-2'-deoxyadenosine, a highly mutagenic lesion found in human DNA. Vitamin C-mediated formation of genotoxins from lipid hydroperoxides in the absence of transition metal ions could help explain its lack of efficacy as a cancer chemoprevention agent.


Subject(s)
Ascorbic Acid/pharmacology , Linoleic Acids/chemistry , Lipid Peroxides/chemistry , Mutagens/chemistry , Aldehydes/chemistry , Aldehydes/metabolism , Antioxidants/chemistry , Ascorbic Acid/adverse effects , Ascorbic Acid/chemistry , Ascorbic Acid/metabolism , Buffers , Copper/pharmacology , Cyclooxygenase 1 , Cyclooxygenase 2 , DNA Adducts/chemistry , DNA Adducts/metabolism , DNA Damage , Epoxy Compounds/chemistry , Epoxy Compounds/metabolism , Ferrous Compounds/pharmacology , Humans , Isoenzymes/metabolism , Linoleic Acids/metabolism , Lipid Peroxides/metabolism , Membrane Proteins , Metals/pharmacology , Mutagens/metabolism , Oxidants/adverse effects , Oxidants/chemistry , Oxidants/metabolism , Oxidants/pharmacology , Oxidation-Reduction , Prostaglandin-Endoperoxide Synthases/metabolism
4.
Bioorg Med Chem Lett ; 11(7): 879-82, 2001 Apr 09.
Article in English | MEDLINE | ID: mdl-11294382

ABSTRACT

A series of 1-phenylpyrazoles was evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds prepared, 1-(3-cyano-4-neopentyloxyphenyl)pyrazole-4-carboxylic acid (Y-700) had the most potent enzyme inhibition and displayed longer-lasting hypouricemic action than did allopurinol in a rat model of hyperuricemia induced by the uricase inhibitor potassium oxonate.


Subject(s)
Gout Suppressants/chemical synthesis , Gout Suppressants/pharmacology , Pyrazoles/chemical synthesis , Pyrazoles/pharmacology , Uric Acid/antagonists & inhibitors , Uric Acid/blood , Xanthine Oxidase/antagonists & inhibitors , Allopurinol/pharmacology , Animals , Area Under Curve , Gout/drug therapy , Gout Suppressants/metabolism , Male , Metabolic Diseases/chemically induced , Metabolic Diseases/drug therapy , Models, Animal , Pyrazoles/metabolism , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Urate Oxidase/antagonists & inhibitors , Urate Oxidase/metabolism , Uric Acid/metabolism , Xanthine Oxidase/metabolism
5.
Biomed Chromatogr ; 15(1): 56-67, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11180302

ABSTRACT

The usefulness of R(-)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole [R(-)-DBD-PyNCS], a fluorescent chiral tagging reagent, for the determination of racemic amines and amino acids, was studied. The reagent reacted with beta-blockers selected as representative secondary amines to produce corresponding fluorescent diastereomers (excitation at 460 nm and emission at 550 nm). The yields of the derivatization reaction were dependent on the stereostructure arround the NH group in beta-blockers. The resulting diastereomers were completely separated with single chromatographic run using linear gradient elutions by reversed-phase chromatography. R(-)-DBD-PyNCS was also applied to the determination of DL-amino acid, considered to be one of the primary amines, in human urine and foodstuffs. DL-amino acids tested equally reacted with the reagent, and the thiocarbamoyl derivatives were separated with an ODS column. The epimerization during the derivatization reaction was negligible judging from the resolution of opposite diastereomers on the chromatogram. The occurence of D-amino acids (D-Ala, D-Ser, D-Asp and/or D-Glu) was identified in the samples tested. The structures and the purities were elucidated with on-line HPLC-MS. The chiral reagent possessing an isothiocyanate group (-NCS) in the structure seems to be applicable to continuous sequential analysis of peptides containing D-amino acids. The thiocarbamoyl derivatives obtained from the reaction with DL-amino acids were converted to thiohydantoins via thiazolinones in acidic medium. The thiohydantoins produced from acidic, basic, neutral, hydroxyl and aromatic amino acids were completely separated with isocratic elutions using acidic mobile phase containing 0.1% TFA. The separations were sufficient for the identification of DL-amino acid in peptide sequences. Although the epimerization during the conversion reaction to thiohydantoins was not avoidable, the descrimination of D- and L-configuration was demonstrated with some commercially available peptides such as beta-lipotropin and [D-Ala2]-deltorphin II. The Edman degaradation method using R(-)-DBD-PyNCS was also adopted to autoanlaysis by gas-phase sequencer. The separation and the detection (UV 254 nm) conditions of the derivatives were used without any change from those for the Edman degradation method using PITC as the tagging reagent. The three DL-amino acid residues (Tyr, Ala and Gly) in [L-Ala2]-leucine-enkephalin and [D-Ala2]-leucine-enkephalin were perfectly identidied with the autoanalysis.


Subject(s)
Amines/analysis , Amino Acids/analysis , Chromatography, High Pressure Liquid/methods , Fluorescent Dyes/chemistry , Isothiocyanates/chemistry , Oxadiazoles/chemistry , Spectrometry, Fluorescence , Stereoisomerism
6.
Dev Biol ; 229(1): 250-61, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11133168

ABSTRACT

Chk1, a nuclear DNA damage/replication G2 checkpoint kinase, phosphorylates Cdc25 and causes its nuclear exclusion in yeast and mammalian cells, thereby arresting the cell at the G2 phase until DNA repair/replication is completed. Chk1 is also involved, at least in part, in the natural G2 arrest of immature Xenopus oocytes, but it is unknown how Chk1 inhibits Cdc25 function and undergoes regulation during oocyte maturation. By using enucleated oocytes, we show here that Chk1 inhibits Cdc25 function in the cytoplasm of G2-arrested oocytes and that Cdc25 is activated exclusively in the cytoplasm of maturing oocytes. Moreover, we show that Chk1 activity is not appreciably altered during maturation, being maintained at basal levels, and that C-terminal truncation mutants of Chk1 have very high kinase activities, strong abilities to inhibit maturation, and altered subcellular localization in oocytes. These results, together with other results, suggest that the Chk1/Cdc25 pathway is involved cytoplasmically in G2 arrest of Xenopus oocytes, but moderately and independent of the G2 checkpoint, and that the C-terminal region of Chk1 negatively regulates its kinase activity and also determines its subcellular localization. Based on these results, we discuss the possibility that Chk1 (with the basal activity) may function as an ordinary regulator of Cdc25 in oocytes (and in other cell types) and that Chk1 might be hyperactivated in response to the G2 checkpoint via its dramatic conformational change.


Subject(s)
Cytoplasm/metabolism , Oocytes/physiology , Protein Kinases/metabolism , cdc25 Phosphatases/metabolism , 14-3-3 Proteins , Animals , Cell Compartmentation , Checkpoint Kinase 1 , Female , G2 Phase/physiology , Models, Biological , Mutation , Peptide Fragments/metabolism , Phosphorylation , Protein Kinases/genetics , Tyrosine 3-Monooxygenase/metabolism , Xenopus , Xenopus Proteins
7.
Res Rep Health Eff Inst ; (92): 151-90; discussion 211-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10925841

ABSTRACT

Analysis of N7-guanine adducts derived from 1,3-butadiene (BD) was conducted with use of liquid chromatography-mass spectrometry (LC-MS) in combination with stable isotope methods. The N7-guanine adducts were shown to undergo spontaneous depurination from DNA in vitro in both calf-thymus DNA and TK6-cell DNA. A comparison was made between BD-derived N7-guanine adduct concentrations both in liver DNA and urine of rats and mice exposed to BD. This has provided insight into the exposure of the animals to 1,2-epoxy-3-butene (BDO), 1,2,3,4-diepoxybutane (BDO2), and 1,2-dihydroxy-3,4-epoxybutane (BDO-diol), the three oxidative metabolites of BD thought to be responsible for BD-mediated carcinogenesis. The liver DNA of mice contained more of the two N7-guanine adducts of BDO--N7-2-hydroxy-3-butenyl-1-guanine (2HB1G) and N7-1-hydroxy-3-butenyl-2-guanine (1HB2G)--than the amounts in rats during the 10-day BD exposure and the 6 days after exposure that were monitored. An excess of 1HB2G over 2HB1G by a factor of approximately 10 in the rat liver and a factor of approximately 5 in the mouse liver was also observed. This regioselective difference was apparent during both the 10-day exposure and the 6 days after exposure. The half-lives of 2HB1G and 1HB2G were estimated as 4.3 days and 3.5 days, respectively, in the DNA of BD-exposed mice and rats. Higher amounts of 2HB1G and 1HB2G appeared in rat urine compared with mouse urine after the 10-day exposure to 1,250 ppm BD. Analysis of liver DNA for N7-guanine adducts derived from BDO2 revealed the presence of two diastereomeric forms of N7-(2,3,4-trihydroxybutyl)-1-guanine (THBG). One of the diastereomers [(+/-)-THBG] was formed by reaction of DNA with (+/-)-BDO2 or BDO-diol, and the other diastereomer (meso-THBG) was formed by reaction of DNA with meso-BDO2 or BDO-diol. There was more (+/-)-THBG and meso-THBG in liver DNA of mice compared with amounts in rats during the 10 days of BD exposure and the 6 days after exposure. A twofold excess of (+/-)-THBG over meso-THBG in rat liver was found at all of the time points monitored. After 10 days of exposure to BD, (+/-)-THBG in mouse liver was also present in an almost twofold excess over meso-THBG. At 6 days after exposure to BD, however, (+/-)-THBG and meso-THBG were present in almost equal amounts in mouse liver. Furthermore, amounts of the two THBG diastereomers in mouse liver 6 days after exposure to BD were almost fivefold greater than amounts in rat liver. The half-lives of (+/-)-THBG and meso-THBG appeared to be longer in mouse liver (4.1 days and 5.5 days, respectively) than in rat liver (3.6 days and 4.0 days, respectively). Higher amounts of (+/-)-THBG were excreted in rat urine compared with mouse urine. It is noteworthy that each of the N7-guanine adducts derived from BD was present in higher concentrations in the liver DNA of mice exposed to 1,250 ppm BD than in the liver DNA of rats exposed to the same dose. Conversely, each of the adducts was present in higher concentrations in the urine of rats compared with the urine of mice after exposure to 1,250 ppm BD.


Subject(s)
Butadienes/toxicity , DNA Adducts/analysis , Mutation , Neoplasms, Experimental/chemically induced , Animals , Biomarkers , Butadienes/metabolism , Carcinogens/metabolism , Carcinogens/toxicity , Cattle , Cell Line , Chromatography, Liquid , Dose-Response Relationship, Drug , Humans , Mass Spectrometry , Mice , Mutagens/metabolism , Mutagens/toxicity , Rats , Rats, Inbred F344
8.
J Anal Toxicol ; 24(3): 194-201, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10774539

ABSTRACT

A sensitive method using reversed-phase liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS) for simultaneous determination of triazolam (TZ) and its hydroxy metabolites in hair has been developed. After the addition of deuterium-labeled 1 -hydroxymethyltriazolam (1-HT-d4) as an internal standard, analytes in hair shaft and hair root samples were extracted with a basic medium, CH2Cl2/MeOH/28% NH4OH (20:80:2), at room temperature overnight. The chromatographic separation of the analytes was achieved using a 3-microm micro HPLC column (100 x 2.0-mm i.d.) with a gradient of acetonitrile in water containing 1% acetic acid as the mobile phase at a flow rate of 0.15 mL/min. The mass spectrometer was operated in selected-ion monitoring mode at quasi molecular ions [M+H]+ of TZ and its metabolites. Under the proposed conditions, the ranges of quantitation of TZ, 1-HT, and 4-HT were 0.1-10 ng/0.2 mL. The method has been applied to determine the hair shaft and hair root incorporation of TZ and its metabolites into Dark Agouti rats administered with 3 mg/kg or 6 mg/kg intraperitoneally twice a day for five days. Judging from the retention behavior by the chromatography and the mass spectra of the peaks detected, TZ, 1-HT, and 4-HT were incorporated in the hair shaft and the hair root. The concentration of 4-HT was the highest of all compounds detected. An unknown substance thought to be 1,4-diHT also appeared in both hair shaft and hair root samples. This substance was obtained from in vitro metabolic studies of TZ using rat liver microsome fraction and was accompanied by the other two metabolites, 1-HT and 4-HT. Structural elucidation was performed with online high-performance liquid chromatography-MS after acetylation of the substance with acetic anhydride and pyridine. This is the first report of the detection of the hydroxy metabolites of TZ in hair. The method has been found to be useful as a screening procedure of TZ intake in humans.


Subject(s)
Hair/chemistry , Triazolam/analysis , Animals , Chromatography, High Pressure Liquid/methods , Hydroxylation , In Vitro Techniques , Male , Mass Spectrometry/methods , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Rats , Rats, Wistar , Triazolam/metabolism
9.
Anal Biochem ; 276(1): 48-58, 1999 Dec 01.
Article in English | MEDLINE | ID: mdl-10585743

ABSTRACT

Seventeen DL-amino acids labeled with a fluorescent chiral labeling reagent, R(-)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N, N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole (R(-)-DBD-PyNCS), were separated by reversed-phase chromatography and detected fluorometrically at 550 nm (excitation at 460 nm). The reagent reacted with amino functional group in dl-amino acids under basic medium. The thiocarbamoyl derivatives were converted to thiohydantoin via thiazolinone in trifluoroacetic acid (TFA) solution. The epimerization ratios during the reaction of the cyclization were less than 37% in all dl-amino acids tested. The resulting thiohydantoin derivatives of individual dl-amino acids were completely separated with isocratic elutions using acidic mobile phase involving 0.1% TFA. The separations of the thiohydantoins yielded from acidic, basic, neutral, hydroxyl, and aromatic amino acids were good enough for the identification of dl-amino acid. The method using the reagent was adopted to identification of dl-amino acid sequences in eight peptides. The separation and identification of the thiohydantoin derivatives liberated from the peptides labeled were performed by the isocratic elutions. The applicability of the proposed procedure to sequential analysis of peptide was demonstrated with [D-Ala(2)]-leucine enkephalin, [D-Ala(2)]-deltorphin II, d-Phe-Met-Arg-Phe-amide, and Phe-D-Met-Arg-Phe-amide. D-Ala, D-Phe, and D-Met in the peptides were positively identified with the proposed procedures. [L-Ala(2)]-leucine enkephalin, beta-lipotropin, Asp-Ser-Asp-Pro-Arg, and Pro-Asp-Val-Asp-His-Val-Phe-Leu-Arg-Phe-amide were also analyzed as the references without D-amino acid.


Subject(s)
Amino Acids/isolation & purification , Chromatography, High Pressure Liquid/methods , Peptides/chemistry , Sequence Analysis, Protein/methods , Amino Acid Sequence , Amino Acids/chemistry , Evaluation Studies as Topic , Fluorescent Dyes , Isothiocyanates , Oxadiazoles , Stereoisomerism , Thiohydantoins
10.
Steroids ; 64(4): 252-8, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10399881

ABSTRACT

16alpha-Hydroxyestrone (16alpha-OHE1), one of the major estrogen metabolites in humans that may plays a role in cell transformation, has been found to form stable adducts with nuclear proteins. The mechanism for the formation of a stable covalent adduct of 16alpha-OHE1 with protein has been postulated via the Heyns rearrangement after Schiff base formation. The Heyns rearrangement on the steroidal D-ring alpha-hydroxyimine was investigated using 17-(2-methoxyethylimino)estra-1,3,5(10)-triene-3,16alpha-dio l as a model intermediate. Rates of the Heyns rearrangement and hydrolysis of the steroidal a-hydroxyimine were determined by a high-performance liquid chromatography (HPLC) simultaneously. The Heyns rearrangement was demonstrated to be optimum at pH 6.2 and the reaction rate at physiological pH, 7.3-7.5, was more than 90% of that at the optimum pH. On the other hand, modulator(s) to the reactions were also examined. According to our previous finding of the proton-mediated mechanism of the Heyns rearrangement, the effects of cationic metal ions on the reactions were examined with 29 metal chlorides. Five metal ions, Pt4+, Cu2+, Ni2+, Co2+, and Mn2+, suppressed the formation of Heyns product significantly while Fe2+, Y3+, Gd3+, and Er3+ slightly increased it. The suppression rate was synergistically enhanced by the combination of Pt4+ with Co2+, Cu2+, or Ni2+. These results suggest the five metal ions, Pt4+, Cu2+, Ni2+, Co2+, and Mn2+, reduce the formation of the Heyns product in vivo and, therefore, would be useful tools to clarify the implication of the stable adduct formation of 16alpha-OHE1 with protein.


Subject(s)
Hydroxyestrones/chemistry , Hydroxyestrones/metabolism , Metals/pharmacology , Cations , Chemical Phenomena , Chemistry, Physical , Chromatography, High Pressure Liquid , Cobalt/pharmacology , Copper/pharmacology , Drug Stability , Erythrocyte Membrane/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Membrane Proteins/metabolism , Molecular Structure , Nickel/pharmacology , Platinum/pharmacology , Serum Albumin/metabolism , Structure-Activity Relationship
11.
Anal Biochem ; 269(1): 124-32, 1999 Apr 10.
Article in English | MEDLINE | ID: mdl-10094782

ABSTRACT

D-Amino acids in food and biological samples labeled with R(-)- and S(+)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N, N-dimethylaminosulfonyl)-2,1,3-benzoxadiazoles (DBD-PyNCS) were separated by reversed-phase chromatography and detected fluorometrically at 550 nm (excitation at 460 nm). DL-Amino acids were efficiently labeled at 55 degrees C for 20 min in basic medium. The resulting thiocarbamoyl-amino acids were resolved by an isocratic elution using water:30% methanol in acetonitrile (72:28) containing 0.1% trifluoracetic acid as mobile phase for hydrophilic amino acids and gradient elutions using sodium acetate buffer (pH 5. 2)/acetonitrile as gradient solvent mixture for hydrophobic amino acids, respectively. The detection limits (S/N = 3) of DL-amino acids tested were in the range of 0.16-0.75 pmol. The proposed method was applied to determine the D-amino acid(s) in milk, cream, fermented dairy products (yogurt and yakult), tomato products (juice, puree, and catchup), fermented beverages (beer and red wine), and human urine. The existence of D-amino acid(s) was demonstrated in all the samples tested. Furthermore, the identification of the D-amino acid(s) was performed using both isomers of DBD-PyNCS and by on-line HPLC-electrospray ionization-MS.


Subject(s)
Amino Acids/analysis , Chromatography, High Pressure Liquid/methods , Fluorescent Dyes , Isothiocyanates , Oxadiazoles , Amino Acids/urine , Beverages/analysis , Dairy Products/analysis , Food , Humans , Solanum lycopersicum/chemistry , Stereoisomerism
12.
Dev Biol ; 207(2): 432-44, 1999 Mar 15.
Article in English | MEDLINE | ID: mdl-10068474

ABSTRACT

Chk1 kinase, a DNA damage/replication G2 checkpoint kinase, has recently been shown to phosphorylate and inhibit Cdc25C, a Cdc2 Tyr-15 phosphatase, thereby directly linking the G2 checkpoint to negative regulation of Cdc2. Immature Xenopus oocytes are arrested naturally at the first meiotic prophase (prophase I) or the late G2 phase, with sustained Cdc2 Tyr-15 phosphorylation. Here we have cloned a Xenopus homolog of Chk1, determined its developmental expression, and examined its possible role in prophase I arrest of oocytes. Xenopus Chk1 protein is expressed at approximately constant levels throughout oocyte maturation and early embryogenesis. Overexpression of wild-type Chk1 in oocytes prevents the release from prophase I arrest by progesterone. Conversely, specific inhibition of endogenous Chk1 either by overexpression of a dominant-negative Chk1 mutant or by injection of a neutralizing anti-Chk1 antibody facilitates prophase I release by progesterone. Moreover, when ectopically expressed in oocytes, a Chk1-nonphosphorylatable Cdc25C mutant alone can induce prophase I release much more efficiently than wild-type Cdc25C; if endogenous Chk1 function is inhibited, however, even wild-type Cdc25C can induce the release very efficiently. These results suggest strongly that Chk1 is involved in physiological prophase I arrest of Xenopus oocytes via the direct phosphorylation and inhibition of Cdc25C. We discuss the possibility that Chk1 might function either as a G2 checkpoint kinase or as an ordinary cell cycle regulator in prophase-I-arrested oocytes.


Subject(s)
Oocytes/enzymology , Protein Kinases/genetics , Xenopus/embryology , cdc25 Phosphatases , Amino Acid Sequence , Animals , Base Sequence , Cell Cycle Proteins/antagonists & inhibitors , Cell Cycle Proteins/metabolism , Checkpoint Kinase 1 , Cloning, Molecular , Embryonic Development , Gene Expression Regulation, Developmental , Meiosis/genetics , Microinjections , Molecular Sequence Data , Mutation , Oocytes/metabolism , Phosphoprotein Phosphatases/antagonists & inhibitors , Phosphoprotein Phosphatases/metabolism , Phosphorylation , Progesterone/pharmacology , Prophase/genetics , Protein Kinases/metabolism , RNA, Messenger/metabolism , Sequence Alignment , Time Factors , Xenopus Proteins
13.
Chem Res Toxicol ; 12(3): 247-57, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10077487

ABSTRACT

Liquid chromatography (LC) in combination with tandem mass spectrometry (MS/MS) and stable isotope methodology was employed for the analysis of the N7-guanine (Gua) adducts derived from 1,2:3, 4-diepoxybutane (BDO2) a reactive metabolite of 1,3-butadiene (BD). Two diastereomeric forms of N7-(2,3,4-trihydroxybutyl)guanine (THBG) were identified in the livers of both mice and rats. One of the diastereomers [(+/-)-THBG] was formed by reaction of DNA with (+/-)-BDO2, and the other diastereomer (meso-THBG) was formed by reaction of DNA with meso-BDO2. There was significantly more (+/-)-THBG and meso-THBG in the liver DNA of the mice when compared with those of the rats during the 10 days of exposure to BD and the 6 days of postexposure that were monitored. There was a 2-fold excess of (+/-)-THBG over meso-THBG in the rat liver at all the time points. In the mouse liver after 10 days of exposure to BD, the (+/-)-THBG (3.9 adducts/10(6) normal bases) was also present in an almost 2-fold excess over meso-THBG (2.2 adducts/10(6) normal bases). However, 6-days after exposure to BD, (+/-)-THBG (1.2 adducts/10(6) normal bases) and meso-THBG (1.0 adduct/10(6) normal bases) were present in almost equal amounts in the mouse liver. Furthermore, there was an almost 5-fold excess of the two THBG diastereomers in the mouse liver DNA 6 days after exposure to BD when compared with rat liver DNA. The half-lives of (+/-)-THBG and meso-THBG appeared to be slightly longer in mouse liver (4.1 and 5.5 days, respectively) than in rat liver (3.6 and 4.0 days, respectively). The apparent persistence of these adducts in the mouse may contribute to the increased susceptibility of this species to BD-induced carcinogenesis. It is possible that (+/-)-THBG and meso-THBG could have also been derived from the reaction of DNA with the hydrolysis product of BDO2, 1,2-dihydroxy-3,4-epoxybutane (DHEB). Surprisingly, a vast majority of the studies in which the mutagenic and carcinogenic potential of BDO2 have been examined have only employed the commercially available (+/-)-BDO2. In light of the present findings, additional studies will be required to determine the potency of meso-BDO2 and the DHEB that is the precursor to meso-THBG as mutagens and carcinogens.


Subject(s)
Butadienes/toxicity , DNA Adducts/metabolism , Guanine/metabolism , Liver/metabolism , Mutagens/toxicity , Animals , Butadienes/metabolism , Chromatography, Liquid , DNA Adducts/chemical synthesis , DNA Adducts/chemistry , Epoxy Compounds/chemistry , Epoxy Compounds/metabolism , Female , Guanine/analogs & derivatives , Guanine/chemical synthesis , Guanine/chemistry , Half-Life , Hydrolysis , Inhalation Exposure , Liver/drug effects , Mass Spectrometry , Mice , Mice, Inbred Strains , Mutagens/metabolism , Rats , Rats, Inbred F344 , Spectrophotometry, Ultraviolet , Stereoisomerism
15.
J Chromatogr B Biomed Sci Appl ; 708(1-2): 285-9, 1998 Apr 24.
Article in English | MEDLINE | ID: mdl-9653974

ABSTRACT

A method was developed for the simultaneous determination of gamma-glutamylglutathione (gamma-GluGSH) and other low-molecular-mass thiol compounds (cysteine, cysteamine, homocysteine, cysteinylglycine, gamma-glutamylcysteine, glutathione and N-acetylcysteine) using high-performance liquid chromatography combined with precolumn fluorescence labeling with ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate (SBD-F). These SBD-labeled thiol compounds were separated within 35 min on a Cosmosil 5C-18AR column with isocratic elution using 75 mM sodium citrate buffer (pH 2.90)-methanol (98:2) and detected fluorimetrically (ex. 386 nm, em. 516 nm). The calibration graphs using 2-mercaptoethanol as an internal standard showed good linearity in the range from 20 pmol to 10 nmol for all thiol compounds examined. The application of this method for the quantitative determination of thiol compounds in the urine from gamma-glutamyl transpeptidase-deficient mice was also demonstrated. This method is sufficiently simple, rapid and sensitive for the determination of gamma-GluGSH and other low-molecular-mass thiol compounds in biological samples.


Subject(s)
Chromatography, High Pressure Liquid/methods , Fluorometry/methods , Glutathione/analogs & derivatives , Sulfhydryl Compounds/analysis , Animals , Calibration , Fluorescent Dyes , Fluorobenzenes , Glutathione/analysis , Mice , Molecular Weight , Oxidation-Reduction , Phosphines , Sensitivity and Specificity , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/urine
16.
Jpn J Antibiot ; 51(12): 746-58, 1998 Dec.
Article in Japanese | MEDLINE | ID: mdl-10077773

ABSTRACT

Clinical efficacy and safety of pareteral sulbactam/ampicillin (SBT/ABPC) was compared with cefotiam (CTM) in a randomized clinical trial of pneumonia in the elderly at 13 National Hospitals of Kyushu island. 37 patients received SBT/ABPC 3 g i.v., b.i.d., and 31 patients received CTM 1 g i.v., b.i.d. for 7 to 14 days. 1. 68 patients (37 for SBT/ABPC and 31 for CTM) were evaluated for safety. No statistical differences were noted in the patients' backgrounds of either group. 2. The clinical efficacy of SBT/ABPC was 96.3% (26/27 cases) while CTM was 75.2% (17/23 cases). This was found to be statistically significant (Fisher's exact test: p < 0.05). 3. 100% of evaluated cases (10 for SBT/ABPC and 4 for CTM) showed bacterial elimination. 4. No side effects were observed in the study. 5. Abnormal laboratory findings were noted in 10.8% (4/37 cases) for SBT/ABPC and 3.2% (1/31 cases) for CTM. The major adverse events were mild elevation of GOT, GPT and A1-P for SBT/ABPC, and mild platelets overproduction for CTM. No statistical differences were noted in both groups. These results are consistent with SBT/ABPC as a highly effective antibiotic in the treatment of elderly patients with pneumonia.


Subject(s)
Drug Therapy, Combination/administration & dosage , Pneumonia, Bacterial/drug therapy , Aged , Aged, 80 and over , Alanine Transaminase/blood , Ampicillin/administration & dosage , Ampicillin/adverse effects , Aspartate Aminotransferases/blood , Cefotiam/administration & dosage , Cefotiam/adverse effects , Cephalosporins/administration & dosage , Cephalosporins/adverse effects , Drug Evaluation , Drug Therapy, Combination/adverse effects , Female , Humans , Infusions, Intravenous , Male , Sulbactam/administration & dosage , Sulbactam/adverse effects , Treatment Outcome
17.
Int J Immunopharmacol ; 14(7): 1195-201, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1280628

ABSTRACT

The effect of a novel synthetic compound, Y-25510, (+-)-3-[4-(2-dimethylamino-1-methylethoxy)phenyl]-1H-pyrazolo[3,4 -b] pyridine-1-acetic acid, on recovery from long-lasting leukopenia induced by 5-fluorouracil was compared with that of recombinant human granulocyte colony-stimulating factor (rhG-CSF). When mice were administered i.p. with 5-FU (200 mg/kg) on days 0 and 7, intravenous administration of Y-25510 (100 and 1000 micrograms/kg) prevented the decrease in the peripheral leukocyte and neutrophil number and accelerated the recovery from leukopenia. Subcutaneous administration of rhG-CSF (50 micrograms/kg) did not prevent leukopenia but accelerated the recovery from leukopenia. In particular, peripheral neutrophil number increased over a normal level. The administration of Y-25510 (10, 100 and 1000 micrograms/kg) restored the decrease in the number of bone marrow cells, spleen cells, lymphocytes, neutrophils and monocytes. The administration of rhG-CSF (50 micrograms/kg) restored the decrease in the number of bone marrow cells, spleen cells, and neutrophils but not that of lymphocytes and monocytes. In fractions of bone marrow cells on day 21, the administration of Y-25510 (1000 micrograms/kg) showed a tendency of restoring the decrease in neutrophil number. In conclusion, the administration of Y-25510 prevented leukopenia and accelerated the recovery from leukopenia in the 5-FU-treated mice. It is suggested that the mechanism of the restorative action of Y-25510 is different from that of rhG-CSF. In a number of immature bone marrow cells Y-25510 has a potent stimulatory effect on the recovery from the decrease in number of hematopoietic cells, keeping a balance in number of each blood cell.


Subject(s)
Adjuvants, Immunologic/pharmacology , Granulocyte Colony-Stimulating Factor/pharmacology , Leukopenia/drug therapy , Pyrazoles/pharmacology , Pyridines/pharmacology , Animals , Bone Marrow/drug effects , Bone Marrow/pathology , Female , Fluorouracil , Hematopoiesis/drug effects , Hematopoietic Stem Cells/drug effects , Leukocyte Count , Leukopenia/blood , Leukopenia/chemically induced , Mice , Mice, Inbred ICR , Spleen/drug effects , Spleen/pathology
18.
Kekkaku ; 67(7): 509-13, 1992 Jul.
Article in Japanese | MEDLINE | ID: mdl-1434315

ABSTRACT

Forty-eight cases of tuberculous pleurisy were examined and the following results were obtained. (1) Most of the patients were male, and there was no significant age and underlying diseases. (2) Fever and chest pain were observed mainly in younger patients, and sputum and dyspnea in older patients. (3) All of the cases examined had exudative pleural effusion, and increased ADA activity was frequently observed. (4) Mycobacterium tuberculosis was detected in the sputum of 65%, and also in the pleural effusion of 28% of the patients. The pathological diagnosis of tuberculosis was made by pleural biopsy in 83% of the patients, suggesting that pleural biopsy is very useful in the diagnosis of tuberculosis pleurisy. (5) The prognosis of the patients with tuberculosis pleurisy was good. Steroid therapy was generally ineffective.


Subject(s)
Tuberculosis, Pleural , Adolescent , Adult , Aged , Aged, 80 and over , Antitubercular Agents/therapeutic use , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Pleural Effusion/microbiology , Prednisolone/therapeutic use , Prognosis , Sputum/microbiology , Tuberculosis, Pleural/drug therapy , Tuberculosis, Pleural/microbiology
19.
Yakugaku Zasshi ; 111(4-5): 225-33, 1991.
Article in Japanese | MEDLINE | ID: mdl-1652011

ABSTRACT

High-performance liquid chromatography (HPLC) with electrochemical detection has been developed for the trace analysis of electrochemically active substances in biological fluids such as catecholamines. The recent development of this system, both instruments and application, has been reviewed. The principle of instrument and newly developed electrode for electrochemical detector have been described at the first section. Series electrodes, especially with coulometric detection, gave much higher selectivity to the analysis of biological substances. The application of HPLC with electrochemical detection to the determination of estrogens in biological fluids clarified the metabolic pathway of catechol estrogens. The applicability to the determination of vitamin D3 and related compounds has been also suggested. For the purpose of extending the applicability of HPLC with electrochemical detection to electro-inactive compounds, pre- and post-column labeling methods have been developed. Pre-column derivatization reagents possessing ferrocene as an electrophore provided a selective and sensitive response to the detector, because of their high-reversibility and low applied potential in the redox reaction. Post-column reaction by using immobilized enzyme reactor has been widely used for the determination of acetylcholine and choline in biological fluids.


Subject(s)
Chromatography, High Pressure Liquid/instrumentation , Electrochemistry/instrumentation , Catecholamines/analysis , Cholecalciferol/analysis , Chromatography, High Pressure Liquid/methods , Electrochemistry/methods , Estrogens/analysis
20.
Nihon Seikeigeka Gakkai Zasshi ; 64(1): 43-9, 1990 Jan.
Article in Japanese | MEDLINE | ID: mdl-2181048

ABSTRACT

Idiopathic herniation of the spinal cord is a very rare disease, only 2 cases being so far reported in the literature. A 61-year-old man with a gradual loss of power in his lower extremities was diagnosed as intradural arachnoid cyst, and underwent operation. During operation, not only an arachnoid cyst was observed dorsally, but was also duplicated the dura mater ventrally. In the latter lesion, a ventral part of the spinal cord was herniated from a defected area of the dural inner layer. Although this dural inner layer as well as the arachnoid cyst was resected, his clinical symptoms remained unchanged after operation. When a shift of the spinal cord is detected in an image, we should precisely determine the relationship between the spinal cord and the dura mater during operation with consideration of a possibility of the presence of idiopathic herniation of the spinal cord.


Subject(s)
Arachnoid , Cysts/complications , Dura Mater/abnormalities , Spinal Cord Diseases/complications , Cysts/surgery , Dura Mater/surgery , Hernia/complications , Hernia/diagnosis , Herniorrhaphy , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Myelography , Spinal Cord Diseases/diagnosis , Spinal Cord Diseases/surgery , Tomography, X-Ray Computed
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