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Zhang Y, Butler J, Pryor B. Comparison of apprehension about communication in China and the United States. Percept Mot Skills 1996; 82:1168-70. [PMID: 8823884 DOI: 10.2466/pms.1996.82.3c.1168] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A translated version of the Personal Report of Communication Apprehension was administered to 688 students at four Chinese colleges and universities. The data were compared with American norms established by McCroskey in 1982 and with the responses of 177 students at a large state university in Florida. The Chinese sample reported a significantly higher mean score on apprehension about communication than the Americans. The findings were discussed with reference to cultural differences.
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Aruoma OI, Spencer JP, Rossi R, Aeschbach R, Khan A, Mahmood N, Munoz A, Murcia A, Butler J, Halliwell B. An evaluation of the antioxidant and antiviral action of extracts of rosemary and Provençal herbs. Food Chem Toxicol 1996; 34:449-56. [PMID: 8655093 DOI: 10.1016/0278-6915(96)00004-x] [Citation(s) in RCA: 161] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Extracts of herbs and spices are increasingly of interest in the food industry because they retard oxidative degradation of lipids. There is also increasing interest in the antiviral activity of plant products. A liquid, deodorized rosemary extract and an oily extract of a mixture of Provençal herbs were tested for antioxidant and antiviral action in vitro. The rosemary extract (Herbor 025) and the extract of Provençal herbs (Spice Cocktail) inhibited peroxidation of phospholipid liposomes with 50% inhibition concentration values of 0.0009% (v/v) and 0.0035% (v/v), respectively. Herbor 025 and the spice cocktail (at 0.2%, v/v) reacted with trichloromethylperoxyl radical with calculated rates of 2.7 x 10(4) s-1 and 1.5 x 10(3) s-1, respectively. The main active components in the herbal preparations, carnosol and carnosic acid, at 0.05% (v/v) react with rate constants of (1-3) x 10(6) M-1 sec-1 and 2.7 x 10(7) M-1 sec-1, respectively. Both extracts show good antioxidant activity in the Rancimat test, especially in lard. Herbor 025 and the spice cocktail inhibited human immunodeficiency virus (HIV) infection at very low concentrations which were also cytotoxic. However, purified carnosol exhibited definite anti-HIV activity at a concentration (8 microM) which was not cytotoxic. Both preparations promoted some DNA damage in the copper-phenanthroline and the bleomycin-iron systems. The two herbal preparations possess antioxidant properties that may make them useful in the food matrix.
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Brabbins C, Butler J, Bentall R. Consent to neuroleptic medication for schizophrenia: clinical, ethical and legal issues. Br J Psychiatry 1996; 168:540-4. [PMID: 8733791 DOI: 10.1192/bjp.168.5.540] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND The effects of neuroleptic medication on schizophrenic patients are both positive (reduction in symptoms) and negative (adverse side-effects). Given that altered cognitive functioning may be a feature of schizophrenia, the use of neuroleptics raises important ethical and legal issues. METHOD A selective review was carried out of papers addressing ethical arguments for and against obtaining consent from schizophrenic patients, and the ethical and legal requirements which must be met for consent to occur. RESULTS Although a balance must be met between arguments for and against obtaining consent, clinicians should seek informed consent in all but exceptional circumstances. Obtaining consent depends on the adequate presentation of information, the absence of duress and the patients' capacity to consent. Various tests of capacity to consent have been proposed. CONCLUSIONS It is proposed that clinicians employ a proforma to record attempts to obtain informed consent during routine clinical practice.
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Lee JM, Baumgartner FJ, Shellans S, Butler J, French S. Degeneration and sarcomatous transformation of a retroperitoneal leiomyoma. THE EUROPEAN JOURNAL OF SURGERY = ACTA CHIRURGICA 1996; 162:337-40. [PMID: 8739423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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355
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Prütz WA, Butler J, Land EJ. Photocatalytic and free radical interactions of the heterocyclic N-oxide resazurin with NADH, GSH, and Dopa. Arch Biochem Biophys 1996; 327:239-48. [PMID: 8619609 DOI: 10.1006/abbi.1996.0116] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Electron donating free radicals NAD(.), (.)CO2(-), MV(.)+, and e(aq)-, generated by pulse radiolysis, reduce resazurin (RNO) with rate constants of 1.9 x 10(9), 2.8 x 10(9), 4.8 x 10(9), and 2.3 x 10(10) M(-1) s(-1), respectively, neutral solution. The semireduced dye (RN(.)-O- disproportionates slowly to RN (resorufin) and RNO. There was little evidence that RN(.)-O- behaves as an oxidizing species capable of initiating chain reactions, for instance via oxidation of NADH to NAD(.). The oxidizing radicals GS(.), (.)OH, and N3(.) interact with RNO via complex consecutive processes, probably by addition-elimination reactions. Stable products generated upon oxidation of RNO by N3(.) exhibit a red-shifted absorption, but GS(.) and (.)OH also cause partial reduction to RN. Neither O2(.)- nor dopa semiquinone nor tyrosine phenoxyl radicals appear to interact with RNO. Radicals formed by reaction of (.)OH with (Gly)3 reduce RNO to RN with stoichiometry near two (gamma-radiolysis), and there is evidence (pulse radiolysis) for direct slow O-atom transfer from RNO to these species. Resazurin is highly photosensitive under anaerobic conditions in presence of H-atom donors like NADH, GSH, or dopa. Under aerobic conditions RNO becomes an efficient catalyst of red light induced photooxidation of these donors; the RN(.)-O- intermediate, formed in the photooxidative process, is apparently recycled to RNO by O2, and by other electron acceptors. Our results suggest that RNO can behave as a photoactive, free radical generating xenobiotic compound.
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356
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Spencer JP, Jenner A, Butler J, Aruoma OI, Dexter DT, Jenner P, Halliwell B. Evaluation of the pro-oxidant and antioxidant actions of L-DOPA and dopamine in vitro: implications for Parkinson's disease. Free Radic Res 1996; 24:95-105. [PMID: 8845917 DOI: 10.3109/10715769609088005] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The antioxidant and pro-oxidant properties of L-DOPA and dopamine were investigated in vitro. Both compounds inhibited the peroxidation of ox-brain phospholipids, with IC50 values of 8.5 microM for dopamine and 450 microM for L-DOPA. Dopamine and L-DOPA reacted with trichloromethyl peroxyl radicals (CCl3O2.) with rate constants of 2.1 x 10(7)M-1s-1 and 1.3 x 10(7)M-1s-1 respectively. The effects of dopamine and L-DOPA on iron ion-dependent hydroxyl radical generation from H2O2 were complex. In general, low concentrations stimulated OH. formation in the presence of ferric-EDTA and, in the case of L-DOPA, ferric-ADP and ferric citrate chelates. Both compounds also reacted with superoxide radical and hypochlorous acid. The products of the reaction with HOCl could still inhibit alpha 1-antiproteinase and appear to be 'long lived' chloramine-type oxidizing species. Our results suggest that L-DOPA and dopamine might have a complex mixture of pro- and anti- oxidant effects, which could contribute to tissue damage due to oxidative stress in Parkinson's disease and other neurological disorders.
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Piscitelli D, Dowell J, Butler J, Devane J, Young D. Population Pharmacokinetics (PPK) of Fampridine Determined by Two Programs: NONMEM and PPHARM. Clin Pharmacol Ther 1996. [DOI: 10.1038/sj.clpt.1996.317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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358
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Butler J. Angioplasty versus bypass surgery. Lancet 1996; 347:271; author reply 272-3. [PMID: 8551923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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359
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Mayalarp SP, Hargreaves RH, Butler J, O'Hare CC, Hartley JA. Cross-linking and sequence specific alkylation of DNA BY aziridinylquinones. 1. Quinone methides. J Med Chem 1996; 39:531-7. [PMID: 8558523 DOI: 10.1021/jm950629q] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The cytotoxicities and DNA cross-linking abilities of 16 1,4-benzoquinones have been investigated. All of the alkylmonoaziridinyl-1,4-benzoquinones were able to interstrand crosslink DNA after reduction and were cytotoxic in vitro. Compounds lacking an aziridine group were unable to cross-link DNA and were less cytotoxic. The methyl analogues were shown to preferentially react at TGC sequences. From comparing the structural requirements for crosslinking and the cytotoxicities, a mechanism has been proposed wherein some hydroquinones can associate and react at TGC sequences in DNA. These hydroquinones can subsequently autoxidize to form a reactive quinone methide which reacts at the opposite strand to form a cross-link.
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Brown R, Kovacs C, Butler J, Wang N, Lehr J, Banzett R. The avian lung: is there an aerodynamic expiratory valve? J Exp Biol 1995; 198:2349-57. [PMID: 9320272 DOI: 10.1242/jeb.198.11.2349] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The unidirectional gas-flow pattern through the avian lung is thought to result from 'aerodynamic valves'; support for this hypothesis lies mainly in the failure to find any evidence for anatomical valves. During expiration, air flows from the caudal air sacs through the major exchange area of the lung, the paleopulmonic parabronchi, instead of bypassing the lungs via the intrapulmonary bronchus. We tested whether the effectiveness of this expiratory flow control mechanism depends on aerodynamic factors, especially convective inertial forces that depend on gas density and flow velocity. In pump-ventilated, anaesthetized geese, a bolus of tracer gas was introduced into both the right and left caudal thoracic air sacs during an end-inspiratory pause. During the first expiration, the rise of tracer levels within the caudal trachea was measured. Valve efficacy was positively correlated with the rate of expiratory gas flow, V·ao (range 8­200 ml s-1). At flows assumed to occur during exercise in geese (V·ao>100 ml s-1), the expiratory valve efficacy was approximately 95 %; it was less effective at lower flows. Surprisingly, the density (rho) of the background gas (rho of He/O2=0.43 g l-1, Ar/O2=1.72 g l-1 or SF6/O2=5.50 g l-1) had no effect on expiratory valving. We suggest two possible mechanisms that might explain this unusual combination of flow dependence without density dependence. (1) If airway geometry changes occurred between experiments with different gases, flow in the vicinity of the expiratory valve may have varied independently from flow measured at the airway opening. (2) Alternatively, valving may depend on dynamic compression of the intrapulmonary bronchus, which could depend mainly on viscous resistance and thus on flow velocity but not gas density.
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Alkhulaifi A, Allen SM, Anderson JR, Argano V, Austin C, Barlow C, Barnard S, Barron D, Berrisford R, Billing S, Brackenbury E, Braidley PC, Bridgewater BJM, Briffa NP, Buchan K, Butler J, Cale ARJ, Carr HMH, Ciulli F, Clark S, Cooper GJ, Craig S, Danton M, Dihimis WC, Duffy J, Duncan A, Gaer J, Gibson G, Griffin SC, Hasan RIR, Hopkinson D, Hornick P, Hunter S, John LCH, Kanagaseay R, Kuo J, Langley S, Levine AJ, Mcnamara V, Oakley EE, Ohri SK, O'Keefe PA, O'Regan D, Parry GW, Pathi VL, Peters P, Prendergast B, Ridley PD, Ritchie AJ, Roxburgh JC, Sharpe DAC, De Souza AC, Steyn R, Tan KK, Tolan M, Trevidi UH, Tsang GMK, Tsui S, Underwood MJ, Unsworth-White MJ, Uppal R, Van Doorn C, Waller DA, Weerasena N, Young V. New deal not satisfactory for cardiothoracic surgery. BMJ : BRITISH MEDICAL JOURNAL 1995. [DOI: 10.1136/bmj.311.7010.953] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Eiserich JP, Butler J, van der Vliet A, Cross CE, Halliwell B. Nitric oxide rapidly scavenges tyrosine and tryptophan radicals. Biochem J 1995; 310 ( Pt 3):745-9. [PMID: 7575405 PMCID: PMC1135961 DOI: 10.1042/bj3100745] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
By utilizing a pulse-radiolytic technique, we demonstrate for the first time that the rate constant for the reaction of nitric oxide (.NO) with biologically relevant tyrosine and tryptophan radicals (Tyr. and Trp. respectively) in amino acids, peptides and proteins is of the order of (1-2) x 10(9) M-1.s-1. We also show that .NO effectively interferes with electron-transfer processes between tryptophan and tyrosine residues in proteins subjected to pulse radiolysis. The near diffusion-controlled rates of these reactions, coupled with the increasingly recognized role of protein radicals in enzyme catalysis and oxidative damage, suggest that Tyr. and Trp. are likely and important targets for .NO generated in vivo.
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365
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Beall HD, Murphy AM, Siegel D, Hargreaves RH, Butler J, Ross D. Nicotinamide adenine dinucleotide (phosphate): quinone oxidoreductase (DT-diaphorase) as a target for bioreductive antitumor quinones: quinone cytotoxicity and selectivity in human lung and breast cancer cell lines. Mol Pharmacol 1995; 48:499-504. [PMID: 7565631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Bioreductive antitumor quinones require reductive metabolism to produce their cytotoxic effects. A series of these compounds was screened for relative rates of reduction by the two-electron reductase, NAD(P)H:quinone oxidoreductase (DTD). The antitumor quinones streptonigrin (SN), 2,5-diaziridinyl-3-phenyl-1,4-benzoquinone (PDZQ), 2,5-diaziridinyl-3,6-dimethyl-1,4-benzoquinine (MeDZQ), and [3-hydroxymethyl-5-aziridinyl-1-methyl-2-(1H-indole-4,7-dione)-propen ol] (EO9) were all excellent substrates for recombinant rat and human DTD. All four compounds were reduced by DTD at least 100 times faster than the clinically important bioreductive alkylating agent, mitomycin C (MC). Reduction of the antitumor quinones was generally 4-5 times more efficient by rat DTD than by human DTD. The exception was EO9, which, surprisingly, was reduced 23 times faster by rat DTD than by human DTD. The rate of reduction of each individual quinone was similar under either aerobic or anaerobic conditions, suggesting that DTD may be an important activating enzyme in the hypoxic fraction of solid tumors. The cytotoxicity of MeDZQ and MC was examined in a panel of human breast and lung cancer cell lines. The data showed good correlations between DTD activity and toxicity for both MeDZQ (r = 0.57, p = 0.054) and MC (r = 0.69, p = 0.020), confirming biochemical data that both compounds are bioactivated by DTD. In addition, IC50 values were in general lower for MeDZQ than for MC in cell lines containing elevated DTD, a finding that was consistent with metabolic data that indicated that MeDZQ was a better substrate for DTD than MC. SR, defined as the ratio of the IC50 value for the H596 NSCLC cell line (undetectable DTD activity) to the IC50 value for the H460 NSCLC cell line (high DTD activity), were determined for all five antitumor quinones. SN was the most selective (SR = 86) followed by EO9 (SR = 62), MeDZQ (SR = 17), and MC (SR = 11). Surprisingly, PDZQ, an excellent substrate for DTD, was toxic to both cell lines (SR = 1.8). These data suggest that antitumor quionones that are substrates for DTD may be selectively toxic to tumors with high DTD activity and may be useful in the treatment of those tumors.
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Ward TH, Haran MS, Whittaker D, Watson AJ, Howard TD, Butler J. Cross-resistance studies on two K562 sublines resistant to diaziridinylbenzoquinones. Biochem Pharmacol 1995; 50:459-64. [PMID: 7646550 DOI: 10.1016/0006-2952(95)00155-s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Two resistant K562 sublines have been developed by treatment with AZQ (2,5-bis(carboethoxyamino)-3,6-diaziridinyl-1,4-benzoquinone) and BZQ (2,5-bis(2-hydroxyethylamino)-3,6-diaziridinyl-1,4-benzoquinone). The ID50 values of for AZQ on K562, the AZQ-resistant sublines (AZQR) and the BZQ-resistant sublines (BZQR) were 0.063, 1.47 and 0.244 microM, respectively. The relative ID50 values for BZQ on the same cell lines were 0.2, 0.67 and 0.83 microM, respectively. Although it is generally believed that these two quinones function by different mechanisms, the two sublines have similar decreased levels of cytochrome P-450 reductase and DT-diaphorase and increased levels of glutathione and superoxide dismutase, compared to the parent cell line. The sublines are also cross-resistant to adriamycin, mitozolamide, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and mitomycin C. This work indicates the potential multifactorial mechanisms by which drug resistance can be induced in cell lines in the absence of conventional 'P'-glycoprotein multidrug resistance.
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367
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Palazidou E, Stephenson J, Butler J, Coskeran P, Chambers S, McGregor AM. Evidence for 5-hydroxytryptamine1A receptor involvement in the control of prolactin secretion in man. Psychopharmacology (Berl) 1995; 119:311-4. [PMID: 7675967 DOI: 10.1007/bf02246297] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of pindolol pretreatment (2 days) on prolactin and cortisol responses to a single dose of (+)-fenfluramine (30 mg po) were examined in nine healthy male volunteers. Pindolol pretreatment attenuated the (+)-fenfluramine-induced increase in prolactin concentrations but failed to affect the (+)-fenfluramine-induced cortisol increase. These data provide evidence in support of 5-HT1A receptor involvement in the regulation of prolactin secretion but question its importance in the regulation of cortisol secretion in man.
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368
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Wilson MR, Polanskey D, Butler J, DiZinno JA, Replogle J, Budowle B. Extraction, PCR amplification and sequencing of mitochondrial DNA from human hair shafts. Biotechniques 1995; 18:662-9. [PMID: 7598901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Techniques have been developed for extracting, amplifying and directly sequencing mitochondrial DNA (mtDNA) from human hair shafts. The hair shaft is ground in a glass micro-tissue grinder, and the DNA is extracted with organic solvent and purified by filtration. The filtrate subsequently provides the mtDNA template for the PCR. The two hypervariable segments of the mtDNA control region are amplified in four separate reactions. After a purification step to remove unincorporated PCR primers, amplified products are quantitated by capillary electrophoresis and subjected to cycle sequencing. The products are separated and analyzed on an automated DNA sequencer. The mtDNA sequences from the hair shaft match the mtDNA sequences from blood samples taken from the same donor.
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369
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Goin J, Giulivi C, Butler J, Cadenas E. Enzymic- and thiol-mediated activation of halogen-substituted diaziridinylbenzoquinones: redox transitions of the semiquinone and semiquinone-thioether species. Free Radic Biol Med 1995; 18:525-36. [PMID: 9101243 DOI: 10.1016/0891-5849(94)00175-j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Activation of 2,5-diaziridinyl-1,4-benzoquinones bearing halogen (Cl, Br, or F) substituents at C3 and C6 by NADPH-cytochrome P450 reductase and glutathione nucleophilic substitution was examined in terms of free radical production and DNA strand scission. A semiquinone species was observed by direct ESR in aerobic conditions during: (a) NADPH-cytochrome P450 reductase-catalyzed reduction of the above quinones. (b) The interaction of these quinones with GSH entailing primarily reactivity of halogen substituents toward sulfur substitution. (c) NADPH-cytochrome P450 reductase-catalyzed activation of products resulting from the quinone/GSH interaction. The semiquinone ESR signal observed during enzymic catalysis was suppressed by superoxide dismutase and was not affected by catalase. ESR studies in conjunction with the spin trapping technique on the autoxidation of the semiquinones formed by the above reaction pathways indicated the formation of superoxide radicals. In addition, thiyl radicals were formed during the reactions following glutathione necleophilic substitution of the above quinones. The ESR signals of both superoxide and thiyl radicals were abolished by superoxide dismutase. No hydroxyl radicals were formed in solution during the redox transitions of these halogen-containing diaziridinylbenzoquinones. Bioreductive activation of these compounds via NADPH-cytochrome P450 reductase or sulfur nucleophilic substitution was associated with the formation of DNA strand breaks. This process was substantially inhibited (74-86%) by superoxide dismutase and to a lesser extent (23-31%) by catalase. It is suggested that DNA strand breakage proceeds in a manner entailing a semiquinone-dependent reduction of metal-ligands bound at the DNA surface and leading to site-specific, hydroxyl radical production.
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Butler J. Negative interference in immunoassays. Clin Chem 1995; 41:481-2. [PMID: 7882535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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372
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Bearn J, Allain T, Coskeran P, Munro N, Butler J, McGregor A, Wessely S. Neuroendocrine responses to d-fenfluramine and insulin-induced hypoglycemia in chronic fatigue syndrome. Biol Psychiatry 1995; 37:245-52. [PMID: 7711161 DOI: 10.1016/0006-3223(94)00121-i] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Chronic fatigue syndrome (CFS) is a disorder characterized by severe physical and mental fatigue and fatiguability of central rather than peripheral origin. We hypothesized that CFS is mediated by changes in hypothalamopituitary function and so measured the adrenocorticotrophic hormone (ACTH), cortisol, growth hormone, and prolactin responses to insulin-induced hypoglycemia, and the ACTH, cortisol, and prolactin responses to serotoninergic stimulation with dexfenfluramine in nondepressed CFS patients and normal controls. We have shown attenuated prolactin responses to hypoglycemia in CFS. There was also a greater ACTH response and higher peak ACTH concentrations (36.44 +/- 4.45 versus 25.60 +/- 2.78 pg ml), whereas cortisol responses did not differ, findings that are compatible with impaired adrenal cortical function. This study provided evidence for both pituitary and adrenal cortical impairment in CFS and further studies are merited to both confirm and determine more precisely their neurobiological basis so that rational treatments can be evolved.
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Aruoma OI, Spencer JP, Butler J, Halliwell B. Reaction of plant-derived and synthetic antioxidants with trichloromethylperoxyl radicals. Free Radic Res 1995; 22:187-90. [PMID: 7704187 DOI: 10.3109/10715769509147538] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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374
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Brizot ML, Snijders RJ, Butler J, Bersinger NA, Nicolaides KH. Maternal serum hCG and fetal nuchal translucency thickness for the prediction of fetal trisomies in the first trimester of pregnancy. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1995; 102:127-32. [PMID: 7538782 DOI: 10.1111/j.1471-0528.1995.tb09065.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To compare the potential value of maternal serum total hCG and free beta-hCG in predicting the risk for fetal trisomies during the first trimester of pregnancy and to examine whether data on maternal hCG and fetal nuchal translucency thickness can be combined to derive risks. METHODS Maternal serum total hCG and free beta-hCG were measured in samples from 83 singleton pregnancies with fetal chromosomal abnormalities (trisomy 21 (n = 41), trisomy 18 (n = 19), trisomy 13 (n = 8) sex chromosome aneuploidies (n = 11), triploidy (n = 4) and 394 chromosomally normal controls at 10 to 13 weeks gestation. In all cases, the fetal nuchal translucency thickness was measured at the time of fetal karyotyping. RESULTS In the 249 chromosomally normal controls with fetal nuchal translucency less than 3 mm, total hCG and free beta-hCG decreased significantly with increased fetal crown-rump length. In 145 chromosomally normal fetuses with nuchal translucency 3 to 9 mm total hCG and free beta-hCG were not significantly different from the 249 with nuchal translucency less than 3 mm. In fetuses with trisomy 21, total hCG and free beta-hCG were significantly higher, whereas in trisomies 18 and 13 levels were lower than in chromosomally normal controls. When the cutoff levels for total hCG and free beta-hCG were selected to include 4% of chromosomally normal fetuses, the detection rates for trisomy 21 were 24% and 32%, respectively. There was no significant association between hCG and nuchal translucency thickness in either the chromosomally normal (r = -0.01) or abnormal group (r = -0.15). CONCLUSION An improved estimate of risk for fetal trisomies at 10 to 13 weeks gestation can be derived by combining data on maternal age, maternal serum total or free beta-hCG and fetal nuchal translucency thickness.
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375
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Behera D, Bernard S, Butler J, Lakshminarayan S. Positive end expiratory pressure reduces bronchial blood flow after aspiration injury. Respiration 1995; 62:10-5. [PMID: 7716348 DOI: 10.1159/000196382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We hypothesized that since added airway pressure compresses bronchial vessels, the airway hyperemia found following airway injury would be reduced by positive end-expiratory pressure (PEEP). Accordingly, we measured the effect of 15 cm H2O PEEP on bronchial and pulmonary blood flows by the radioactive microsphere reference flow technique in closed chested goats (n = 7) before and after aspiration injury to the left lung with 0.1 N HCl. Thirty minutes after aspiration, the pulmonary blood flow to the injured left lung was reduced by one third, whereas the total bronchial blood flow to the left lung (normalized to mean systemic pressure of 100 torr) doubled (11.3 +/- 2.2 to 20.6 +/- 1.0 ml/min 100 torr; p < 0.01). Increasing PEEP from 5 to 15 cm H2O decreased total bronchial blood flow by about half both before (11.3 +/- 2.2 falling to 5.7 +/- 1.4 ml/min/100 torr) and after injury (20.6 +/- 1.0 falling to 10.3 +/- 2.7 ml/min/100 torr). The airway portion (down to 2-3 mm airways) of the total bronchial blood flow of the injured lung increased more than three-fold (1.4 +/- 0.5 rising to 5.5 +/- 1.3 ml/min/100 torr; p < 0.01). This increased flow after aspiration was less affected by PEEP of 15 cm H2O (5.5 +/- 1.3 to 2.8 +/- 0.7 ml/min/100 torr, p = 0.09) than before injury (1.4 +/- 0.5 falling to 0.5 +/- 0.1 ml/min/100 torr; p < 0.05). The increase of the parenchymal portion of the bronchial blood flow after injury, although apparent (9.9 +/- 1.8 increasing to 15.1 +/- 1.2 ml/min/100 torr), was not significant (p = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)
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