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Pavord ID, Wisniewski A, Tattersfield AE. Inhaled frusemide and exercise induced asthma: evidence of a role for inhibitory prostanoids. Thorax 1992; 47:797-800. [PMID: 1481179 PMCID: PMC464049 DOI: 10.1136/thx.47.10.797] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Inhaled frusemide protects subjects with asthma against a wide range of bronchoconstrictor challenges, including allergen, exercise and inhaled sodium metabisulphite. An investigation was designed to determine whether this protection is related to the production of inhibitory prostaglandins, such as prostaglandin E2 (PGE2), by studying the effect of the cyclooxygenase inhibitor indomethacin on the protection afforded by inhaled frusemide against exercise induced asthma. METHODS In a double blind crossover study 10 subjects with mild asthma were pretreated with indomethacin (50 mg thrice daily) or placebo capsules for three days; they then inhaled frusemide (40 mg) or placebo 10 minutes before an exercise test previously shown to cause a 20-30% fall in forced expiratory volume in one second (FEV1). RESULTS After inhalation of placebo exercise caused a similar maximum fall in FEV1 whether pretreatment was with placebo (26%) or indomethacin (25.2%). After inhalation of frusemide the maximum fall in FEV1 was reduced to 14.3% after placebo pretreatment and to 21.8% after indomethacin pretreatment; the difference between placebo and indomethacin pretreatment was significant (mean difference 7.5%, 95% limits 0.6%, 14.4%). The inhibitory effect of frusemide on the response to exercise, assessed as change in FEV1 over 30 minutes, was significantly greater with placebo (62%) than indomethacin (13%) pretreatment. CONCLUSION These findings support a role for inhibitory prostanoids, such as PGE2, in the beneficial effects of frusemide as a protection against exercise induced asthma.
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Knox AJ, Campos-Gongora H, Wisniewski A, MacDonald IA, Tattersfield AE. Modification of bronchial reactivity by physiological concentrations of plasma epinephrine. J Appl Physiol (1985) 1992; 73:1004-7. [PMID: 1400010 DOI: 10.1152/jappl.1992.73.3.1004] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Circulating epinephrine concentrations are altered in certain pathophysiological states, but whether such changes in epinephrine concentrations can alter bronchial responsiveness in subjects with asthma has not been studied. We studied 10 subjects with asthma in a double-blind crossover study on 4 nonconsecutive days. After measurement of baseline forced expiratory volume in 1 s (FEV1) and plasma epinephrine concentration, subjects were given placebo or 4, 16, or 64 ng.kg-1.min-1 epinephrine by intravenous infusion for 45 min. Blood was taken for plasma epinephrine concentration before the infusion and at 30 min, when a histamine challenge test was performed. Mean plasma epinephrine concentrations ranged from 0.37 nmol/l on placebo to 3.76 nmol/l with the 64-ng/kg infusion. FEV1 increased progressively with increasing concentrations of infused epinephrine, the mean change ranging from -0.051 on placebo to 0.331 after the highest concentration of epinephrine. The provocative dose of histamine causing a 20% fall in FEV1 increased progressively with increasing concentrations of infused epinephrine, geometric mean values ranging from 0.61 mumol with placebo to 1.7 mumol after the highest dose of epinephrine. Thus epinephrine, at physiological plasma concentrations, can modify bronchial reactivity.
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Vathenen AS, Knox AJ, Wisniewski A, Tattersfield AE. Effect of inhaled budesonide on bronchial reactivity to histamine, exercise, and eucapnic dry air hyperventilation in patients with asthma. Thorax 1991; 46:811-6. [PMID: 1771604 PMCID: PMC1021035 DOI: 10.1136/thx.46.11.811] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND It has been suggested that inhaled corticosteroids may provide greater protection against constrictor stimuli that act indirectly such as exercise than those that act directly such as histamine. METHODS The effects of six weeks treatment with inhaled budesonide (800 micrograms twice daily) on bronchial reactivity to histamine, exercise, and eucapnic voluntary hyperventilation of dry air were compared in a double blind, placebo controlled, non-crossover study in 40 subjects with asthma. Change in bronchial reactivity to histamine and eucapnic hyperventilation over the six weeks was measured as change in the provocative dose of histamine or dry air causing a 20% fall in FEV1 (PD20 histamine and PV20 eucapnic hyperventilation (EVH) of dry air); this was not possible for exercise because of the development of refractoriness. To enable the change in response to all three stimuli to be compared, the response (percent fall in FEV1) to a fixed dose was measured for all three challenge tests. RESULTS After budesonide there was an increase in PD20 histamine from 0.48 to 2.81 mumol and in PV20 EVH from 364 to 639 litres, and a significant correlation between the changes in PD20 histamine and PV20 EVH (r = 0.63). The median percentage fall in FEV1 in response to eucapnic hyperventilation, exercise, and histamine was similar before budesonide (25.5%, 26.6%, and 24.5%); the reduction in the percentage fall in FEV1 with budesonide was also similar for the three challenges (18.9%, 17.5%, and 16.6%), and all differed significantly from the changes following placebo. There was a significant correlation between change in percentage fall in FEV1 after budesonide with the three stimuli (histamine v exercise: r = 0.48; histamine v eucapnic hyperventilation: r = 0.46; exercise v eucapnic hyperventilation: r = 0.63). CONCLUSION The similar magnitude of change in bronchial reactivity to all three stimuli after budesonide and the within subject correlation obtained between these changes suggest that corticosteroids act by a common mechanism to protect against eucapnic hyperventilation, exercise, and histamine.
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Pavord ID, Wisniewski A, Mathur R, Wahedna I, Knox AJ, Tattersfield AE. Effect of inhaled prostaglandin E2 on bronchial reactivity to sodium metabisulphite and methacholine in patients with asthma. Thorax 1991; 46:633-7. [PMID: 1948791 PMCID: PMC463348 DOI: 10.1136/thx.46.9.633] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Inhaled frusemide protects against the bronchoconstrictor response to a wide range of stimuli that cause bronchoconstriction by indirect mechanisms. One possible explanation for this protection relates to the known ability of frusemide to enhance synthesis of prostaglandin E2 (PGE2). Studies in vitro suggest that PGE2 might protect against indirectly acting bronchoconstrictor challenges rather than those that act directly on airway smooth muscle, though little is known about the effects of PGE2 in vivo. The effect of inhaled PGE2 on the bronchoconstrictor response to inhaled sodium metabisulphite (a stimulus with an indirect action) and methacholine (which acts directly on airway smooth muscle) was studied in nine patients with asthma. Subjects were studied on four days, inhaling PGE2 (100 micrograms) or placebo in a double blind fashion followed immediately by a cumulative dose challenge with sodium metabisulphite or methacholine. The response to the constrictor stimuli was measured as the provocative dose causing a 20% fall in FEV1 (PD20). There was no significant change in FEV1 after inhaled PGE2 compared with placebo, nor any significant change in the response to methacholine; the geometric mean methacholine PD20 was 0.9 mumol after PGE2 and 0.56 mumol after placebo (mean difference 0.7 (95% confidence limits--0.1, 1.5) doubling doses). PGE2, however, protected against sodium metabisulphite, the geometric mean sodium metabisulphite PD20 being 11.8 mumol after PGE2 and 1.8 mumol after placebo (mean difference 2.5 (95% CL 1.9, 3.1) doubling doses). PGE2 conferred significantly greater protection against sodium metabisulphite than methacholine (mean difference 1.8 (95% CL 0.8, 2.8) doubling doses). This suggests that PGE2, like frusemide, has an inhibitory effect on pathways relevant to the bronchoconstriction induced by sodium metabisulphite, with little or no effect on those relevant to methacholine.
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Vathenen AS, Knox AJ, Wisniewski A, Tattersfield AE. Time course of change in bronchial reactivity with an inhaled corticosteroid in asthma. THE AMERICAN REVIEW OF RESPIRATORY DISEASE 1991; 143:1317-21. [PMID: 2048819 DOI: 10.1164/ajrccm/143.6.1317] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The time course of change in FEV1, bronchial reactivity, and daily measures of asthma control (peak expiratory flow, symptoms, and beta 2-agonist inhaler use) was determined during 6 wk of treatment with inhaled budesonide, 800 micrograms twice a day, and for 2 wk following cessation of treatment in 40 asthmatic subjects in a double-blind, placebo-controlled, parallel group study. Histamine reactivity, expressed as the provocative dose of histamine causing a 20% fall in FEV1 (PD20), was measured at intervals during the 8 wk of the study, with more frequent measurements after the first and last dose of drug to provide a detailed profile of change at the start and end of treatment. The first dose of budesonide caused a small increase in median values of FEV1 (0.2 L) and PD20 (1.0 doubling dose of histamine), which was maximum at 6 h. There was a further increase in FEV1 and PD20 over the 6 wk in the budesonide group relative to placebo, the maximum increases (0.53 L, 3.4 doubling doses of histamine) being recorded 6 h after the last dose on Day 42. Following cessation of treatment, FEV1 and PD20 declined and PD20 returned to placebo values at 1 wk. Median PEF increased by 40 and 30 L/min in the morning and evening, respectively, with budesonide treatment. Symptom scores and beta 2-agonist inhaler use were lower in the budesonide group than the placebo group during treatment but tended to be similar (symptom scores) or higher (beta 2-agonist) in the 2 wk following cessation of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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Knox AJ, Wisniewski A, Cooper S, Tattersfield AE. A comparison of the Yan and a dosimeter method for methacholine challenge in experienced and inexperienced subjects. Eur Respir J 1991; 4:497-502. [PMID: 1855579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bronchial reactivity is being measured with increasing frequency in epidemiological studies, but there debate continues about the relative merits of the different methods used to measure reactivity, particularly for subjects with no previous experience of reactivity testing as is the case in epidemiological studies. Repeatability is likely to improve with practice, and laboratory based studies on experienced subjects may overestimate the repeatability of a test in inexperienced subjects. We have compared the repeatability of the Yan method with a dosimeter (Mefar) method of administering methacholine to 40 asthmatic subjects: 20 with experience of methacholine challenge on at least six previous occasions and 20 with no previous experience. Subjects attended the laboratory on four days within a two week period, at the same time of day. A methacholine challenge was performed on two occasions using the Yan method and on two occasions using the dosimeter. Methacholine responsiveness was measured as the provocative dose causing a 20% reduction in forced expiratory volume in one second (PD20FEV1). Geometric mean PD20FEV1 values with the Yan method were 1.14 doubling doses (DD) of methacholine higher than with the dosimeter method. In the experienced subjects, the 95% range for a single estimate was +/- 1.56 DD for the Yan method and +/- 1.37 DD for the dosimeter method. In the inexperienced subjects, the 95% ranges were +/- 2.65 and +/- 1.87 DD for the Yan and dosimeter methods, respectively. Thus, the differences in repeatability between the Yan and dosimeter methods, were small; experienced subjects gave more repeatable values than inexperienced subjects.
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Knox AJ, Wisniewski A, Cooper S, Tattersfield AE. A comparison of the Yan and a dosimeter method for methacholine challenge in experienced and inexperienced subjects. Eur Respir J 1991. [DOI: 10.1183/09031936.93.04040497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bronchial reactivity is being measured with increasing frequency in epidemiological studies, but there debate continues about the relative merits of the different methods used to measure reactivity, particularly for subjects with no previous experience of reactivity testing as is the case in epidemiological studies. Repeatability is likely to improve with practice, and laboratory based studies on experienced subjects may overestimate the repeatability of a test in inexperienced subjects. We have compared the repeatability of the Yan method with a dosimeter (Mefar) method of administering methacholine to 40 asthmatic subjects: 20 with experience of methacholine challenge on at least six previous occasions and 20 with no previous experience. Subjects attended the laboratory on four days within a two week period, at the same time of day. A methacholine challenge was performed on two occasions using the Yan method and on two occasions using the dosimeter. Methacholine responsiveness was measured as the provocative dose causing a 20% reduction in forced expiratory volume in one second (PD20FEV1). Geometric mean PD20FEV1 values with the Yan method were 1.14 doubling doses (DD) of methacholine higher than with the dosimeter method. In the experienced subjects, the 95% range for a single estimate was +/- 1.56 DD for the Yan method and +/- 1.37 DD for the dosimeter method. In the inexperienced subjects, the 95% ranges were +/- 2.65 and +/- 1.87 DD for the Yan and dosimeter methods, respectively. Thus, the differences in repeatability between the Yan and dosimeter methods, were small; experienced subjects gave more repeatable values than inexperienced subjects.
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Deicken RF, Hubesch B, Jensen PC, Sappey-Marinier D, Krell P, Wisniewski A, Vanderburg D, Parks R, Fein G, Weiner MW. Alterations in brain phosphate metabolite concentrations in patients with human immunodeficiency virus infection. ARCHIVES OF NEUROLOGY 1991; 48:203-9. [PMID: 1993012 DOI: 10.1001/archneur.1991.00530140099022] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Human immunodeficiency virus (HIV)-infected individuals often demonstrate neuropsychiatric impairment; however, it is unclear how brain metabolism may be altered in such patients. We used in vivo phosphorus 31 magnetic resonance spectroscopy to noninvasively assess brain energy and phospholipid metabolism by measuring brain concentrations of adenosine triphosphate (ATP), phosphocreatine (PCr), and inorganic phosphate (Pi), as well as phospholipid compounds and intracellular pH. In study 1, 17 HIV-seropositive men with varying degrees of neuropsychiatric impairment and six control subjects were studied. Localized spectra were obtained from a heterogeneous 5 x 5 x 5-cm volume of interest (VOI). Patients with HIV infection had a significantly lower ATP/Pi ratio and a trend for a lower PCr/Pi ratio than did the control group. In addition, the ATP/Pi and PCr/Pi ratios were both significantly negatively correlated with overall severity of neuropsychiatric impairment. In study 2, three HIV-seropositive men with neuropsychiatric impairment were compared with 11 HIV-seronegative men. Localized phosphorus 31 magnetic resonance spectra were obtained from two relatively homogeneous VOIs: (1) a predominantly white matter VOI, and (2) a predominantly subcortical gray matter VOI. The three HIV-infected patients demonstrated significantly decreased ATP and PCr concentrations in the white matter VOI. These results suggest that HIV infection of the brain may impair brain cellular oxidative metabolism and that the degree of metabolic compromise may be related to the severity of neuropsychiatric impairment.
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Singh V, Wisniewski A, Britton J, Tattersfield A. Effect of yoga breathing exercises (pranayama) on airway reactivity in subjects with asthma. Lancet 1990; 335:1381-3. [PMID: 1971670 DOI: 10.1016/0140-6736(90)91254-8] [Citation(s) in RCA: 131] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of two pranayama yoga breathing exercises on airway reactivity, airway calibre, symptom scores, and medication use in patients with mild asthma were assessed in a randomised, double-blind, placebo-controlled, crossover trial. After baseline assessment over 1 week, 18 patients with mild asthma practised slow deep breathing for 15 min twice a day for two consecutive 2-week periods. During the active period, subjects were asked to breathe through a Pink City lung (PCL) exerciser--a device which imposes slowing of breathing and a 1:2 inspiration:expiration duration ratio equivalent to pranayama breathing methods; during the control period, subjects breathed through a matched placebo device. Mean forced expiratory volume in 1 s (FEV1), peak expiratory flow rate, symptom score, and inhaler use over the last 3 days of each treatment period were assessed in comparison with the baseline assessment period; all improved more with the PCL exerciser than with the placebo device, but the differences were not significant. There was a statistically significant increase in the dose of histamine needed to provoke a 20% reduction in FEV1 (PD20) during pranayama breathing but not with the placebo device. The usefulness of controlled ventilation exercises in the control of asthma should be further investigated.
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Dobrzynski L, Wisniewski A, Uemura YJ, Shapiro SM, Wicksted JP. Inelastic neutron scattering from Sendust. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 37:7175-7181. [PMID: 9944003 DOI: 10.1103/physrevb.37.7175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Mukherjee S, Wisniewski A, Bilder R, Sackeim HA. Possible association between tardive dyskinesia and altered carbohydrate metabolism. ARCHIVES OF GENERAL PSYCHIATRY 1985; 42:205. [PMID: 3977545 DOI: 10.1001/archpsyc.1985.01790250099016] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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McKay SE, Golden CJ, Moses JA, Fishburne F, Wisniewski A. Correlation of the Luria-Nebraska Neuropsychological Battery with the WAIS. J Consult Clin Psychol 1981; 49:940-6. [PMID: 7309961 DOI: 10.1037/0022-006x.49.6.940] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Ellis RJ, Wisniewski A, Potts R, Calhoun C, Loucks P, Wells MR. Reduction of flow rate and arterial pressure at moderate hypothermia does not result in cerebral dysfunction. J Thorac Cardiovasc Surg 1980; 79:173-80. [PMID: 7351842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Ellis RJ, Wisniewski A, Potts R, Calhoun C, Loucks P, Rose Wells M. Reduction of flow rate and arterial pressure at moderate hypothermia does not result in cerebral dysfunction. J Thorac Cardiovasc Surg 1980. [DOI: 10.1016/s0022-5223(19)37971-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Cogan MG, Covey CM, Arieff AI, Wisniewski A, Clark OH, Lazarowitz V, Leach W. Central nervous system manifestations of hyperparathyroidism. Am J Med 1978; 65:963-70. [PMID: 742632 DOI: 10.1016/0002-9343(78)90748-9] [Citation(s) in RCA: 131] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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