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White L, Johnston H, Jones R, Mameghan H, Nayanar V, McWhirter W, Kellie S, Waters K, Toogood I. Postoperative chemotherapy without radiation in young children with malignant non-astrocytic brain tumours. A report from the Australia and New Zealand Childhood Cancer Study Group (ANZCCSG). Cancer Chemother Pharmacol 1993; 32:403-6. [PMID: 8339393 DOI: 10.1007/bf00735928] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Young children with malignant brain tumours have particularly poor survival and manifest severe sequelae of radiation therapy. A multi-institutional pilot study of post-operative primary chemotherapy for children under 3 years with primitive neuroectodermal tumours (PNET) or ependymoma was initiated in 1987. The chemotherapy protocol comprised carboplatin, vincristine and the "eight drugs in 1 day" regimen. Radiation was recommended only if tumour progression or recurrence was documented. A total of 14 patients between 5 and 36 months of age were enrolled. Seven had supratentorial tumours (PNET, pinealoblastoma, intracranial retinoblastoma) with multiple predictors of adverse outcome. Four of these responded to initial chemotherapy but subsequently progressed and all had died by 16 months from diagnosis. The seven patients with infratentorial tumours (three medulloblastomas, four ependymomas) had more favourable predictors of outcome: no meningeal dissemination and gross macroscopic resection in six of the seven cases. One patient progressed rapidly and died within 5 months. The other six are alive at 37-57 months from diagnosis. Four are in continuous complete remission at 57, 51, 41 and 37 months, respectively from the time of their tumour resection. One is described as having stable disease with a persistent radiographic lesion at 41 months from diagnosis. One has relapsed on two occasions and is the only surviving patient to have been irradiated. Intelligence scores for the six long-term survivors have thus for remained within the normal range. It is suggested that some infants with standard-risk ependymoma and, possibly, medulloblastoma may be cured without radiation therapy.
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Sohn HJ, Stokes GS, Johnston H. An Na, K ATPase inhibitor from ultrafiltrate obtained by hemodialysis of patients with uremia. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1992; 120:264-71. [PMID: 1323635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ultrafiltrate obtained by hemodialysis of patients with uremia who were not taking cardiac glycosides was used as a source of Na, K adenosine triphosphatase inhibitor for purification and further study. Inhibitory activity was measured by a linked-enzyme assay and by effect on rubidium 86 uptake in guinea pig aortic strips. Two approaches were used in purification: dialysis with a 500 dalton membrane followed by gel filtration with Sephadex G-25, and removal of protein by acidification and boiling followed by Sephadex G-10. The first procedure failed to separate the inhibitor from the salt fraction, whereas the second separated the inhibitor from the salt peak but resulted in partial coelution of the inhibitor with endogenous pyruvate, which interferes with the linked-enzyme assay. Pooled, concentrated G-10 elution fractions from the early part of the inhibitor peak, which were free of pyruvate, produced a dose-response relationship by enzymatic assay that was close to parallel with that for ouabain. Like ouabain, these fractions also inhibited 86Rb uptake in guinea pig aorta. Despite these properties, our previous work has demonstrated that the inhibitor, unlike some other ouabain-like or digitalis-like substances obtained from blood or urine, has no apparent role in body fluid homeostasis.
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Purvis-Smith SG, Saville T, Manass S, Yip MY, Lam-Po-Tang PR, Duffy B, Johnston H, Leigh D, McDonald B. Uniparental disomy 15 resulting from "correction" of an initial trisomy 15. Am J Hum Genet 1992; 50:1348-50. [PMID: 1598916 PMCID: PMC1682578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Stokes GS, Monaghan JC, Flemming CL, Johnston H, Jones M, Pinkerton G, Baber R. Effects of oral contraceptives containing oestrogen combined with norethisterone or levonorgestrel on erythrocyte cation transport in normal women. Clin Sci (Lond) 1992; 82:505-12. [PMID: 1317759 DOI: 10.1042/cs0820505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. Studies were undertaken in pre-menopausal women to examine the effects of treatment with standard oestrogen-progestogen and progestogen-ony oral contraceptives on erythrocyte Na+,K+ co-transport and Na(+)-Na+ countertransport over 3- and 6-month periods. Concurrent observations were made on other erythrocyte cation transport components, plasma lipid concentrations, plasma renin activity, plasma aldosterone concentration and blood pressure. 2. Na+,K+ co-transport, measured as the ouabain-resistant, frusemide-sensitive component of 86Rb+ influx, and Na(+)-Na+ countertransport, measured as the ouabain-resistant, phloretin-sensitive component of 22Na+ influx, were both increased in women taking, on days 1-21 of their cycle, ethinyloestradiol (30-50 micrograms) combined with norethisterone (1000 micrograms or 500-1000 micrograms) for 3 or 6 months. Neither of these fluxes was increased in a control group of women, or in women treated for the same time periods with ethinyloestradiol combined with levonorgestrel. 3. In a separate study of erythrocyte cation transport (excluding Na(+)-Na+ countertransport), in which women undertook treatment with norethisterone only (350 micrograms/day) for 6 months starting 6 weeks post partum, no changes in Na+,K+ co-transport were observed at 3 or 6 months; there were no changes in cation transport in a corresponding control group. 4. The results of these studies confirm that certain oral contraceptive compounds can alter erythrocyte cation transport, and indicate that norethisterone in higher dose preparations is the component predominantly responsible. The alterations observed could not be explained by a direct link with concurrent changes in plasma triacylglycerol concentrations or in the renin-aldosterone axis and were not closely associated with elevation of blood pressure.
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Stokes GS, Monaghan JC, Marwood JF, Okoro EO, Johnston H. Increase in serum total angiotensin-converting enzyme activity with enalapril therapy in humans: a controlled trial. Clin Exp Pharmacol Physiol 1992; 19:297-9. [PMID: 1325880 DOI: 10.1111/j.1440-1681.1992.tb00456.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. In a controlled, randomized double-blind trial, 15 patients with essential hypertension were treated with enalapril 5-20 mg/day, or doxazosin 1-8 mg/day, during a 7 week dose titration phase. This was followed by 7 weeks of combined treatment with doxazosin and enalapril. 2. Blood was taken after a 2 week placebo run-in phase, and at 3 and 7 weeks in the single-agent and combined treatment phases, for measurement of plasma renin activity (PRA), plasma angiotensin II (AII), plasma aldosterone and serum free and total angiotensin-converting enzyme (ACE) activities. 3. Doxazosin had no effect on serum free or total ACE activities. 4. Enalapril reduced serum free ACE activity and increased serum total ACE activity, which at 7 weeks was significantly greater than in patients receiving doxazosin. 5. In those patients who received enalapril, 10 mg/day for 3 weeks and then 20 mg/day for 4 weeks (n = 12), with or without doxazosin, mean serum total ACE activity increased by 51%. PRA was also increased in this group, but there were no changes in plasma AII or aldosterone concentrations.
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McCance DR, Hadden DR, Atkinson AB, Johnston H, Kennedy L. The relationship between long-term glycaemic control and diabetic nephropathy. THE QUARTERLY JOURNAL OF MEDICINE 1992; 82:53-61. [PMID: 1438668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Urine albumin excretion was studied by two widely accepted methods in 210 patients with insulin-dependent diabetes mellitus and related to the mean of serial glycosylated haemoglobin (HbA1) measurements made every 3 months during the previous 6 years. Microalbuminuria (albumin excretion rate > 20 micrograms/min) was present in 9.5 per cent of patients when defined by a 24-hour collection and 8.1 per cent of patients when defined by a timed overnight urine sample. Those with microalbuminuria, as estimated from a timed overnight urine sample, had a longer duration of diabetes but otherwise did not differ in age, duration of diabetes or arterial blood pressure from patients whose albumin excretion rate was 20 micrograms/min or less irrespective of the method of urine collection. The mean and the most recent HbA1 levels differed significantly between the normal and the microalbuminuric groups when defined by the 24-hour albumin excretion rate (p < 0.001, p < 0.01), but no significant difference between these groups was found when albumin excretion rates were calculated from the timed overnight urine sample. Albumin excretion rate, examined in relation to mean HbA1, increased significantly with worsening glycaemic control whether measured over 24 hours or overnight (p < 0.05, p < 0.01). These findings support an association between glycaemic control and microalbuminuria, but the correlation is weak, dependent on the method of urine collection and is just as good for a relatively short-term as for a long-term measure of average blood glucose.
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March JS, Johnston H, Jefferson JW, Kobak KA, Greist JH. Do subtle neurological impairments predict treatment resistance to clomipramine in children and adolescents with obsessive-compulsive disorder? J Child Adolesc Psychopharmacol 1990; 1:133-40. [PMID: 19630661 DOI: 10.1089/cap.1990.1.133] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACT A 10-week double-blind, placebo-controlled design was employed to investigate the effectiveness of clomipramine (CMI) versus placebo in 16 outpatients (ages 10-18 years) with obsessive-compulsive disorder (OCD). While a trend favoring clomipramine was observed, the difference in efficacy between clomipramine (N=8) and placebo (N=8) did not reach statistical significance, partly due to small sample size (N = 6,8). Post-hoc exclusion of two clomipramine-resistant subjects with subtle neurological impairments did, however, yield a statistically significant improvement with drug treatment. Neurological impairments are commonly seen in children with OCD, and may be a risk factor for the disorder during childhood. Speculatively, subtle neurological impairments may also predict resistance to CMI therapy in some patients, and influence the outcome of clinical and research medication trials, depending on differences in neurological inclusion and exclusion criteria.
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Stokes GS, Norris LA, Marwood JF, Johnston H, Caterson RJ. Effect of dialysis on circulating Na,K ATPase inhibitor in uremic patients. Nephron Clin Pract 1990; 54:127-33. [PMID: 2156180 DOI: 10.1159/000185832] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Deproteinized plasma from patients with renal failure had an inhibitory effect on Na,K ATPase activity measured in vitro by a linked-enzyme assay. No inhibitory effect was observed with plasma from normal subjects or from patients undergoing chronic ambulatory peritoneal dialysis. The inhibition of Na,K ATPase whether measured by the linked-enzyme assay or by 86Rb uptake in guinea pig aortic strips was decreased acutely by a single hemodialysis treatment, but was unaffected during a time-control study or ultrafiltration. Changes in Na,K ATPase activity and in Rb uptake were correlated, indicating that the presence of the enzyme inhibitor in uremic plasma was associated with depressed Na pump activity. Change in inhibition of Na,K ATPase activity did not correlate with change in body weight. Dialysis in vitro against a membrane of molecular weight 3,500 cut-off decreased the inhibitory effect of uremic plasma on Na,K ATPase. It was concluded that a dialyzable, low-molecular-weight Na,K ATPase inhibitor circulates in uremia but has no demonstrable role in volume homeostasis.
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Paryani SB, Marsland TA, Faucher P, Fontanelli E, Freeman M, Johnston H, Morrow W, Prabhu P, Stearman M, Vines F. Breast Cancer Screening Project in Northeast Florida. THE JOURNAL OF THE FLORIDA MEDICAL ASSOCIATION 1990; 77:29-31. [PMID: 2299324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The American Cancer Society--Duval Unit, in June, 1987, helped organize a community demonstration screening project involving all hospitals and institutions with mammography units in the area. A Northeast Florida Cooperative Breast Cancer Screening Group was formed comprised of physicians and administrators from each institution. A total of 1,200 women agreed to participate in the project and each underwent complete screening including education, instruction in self-examination, physical examination by a physician and mammography as indicated according to ACS guidelines. Of the study group, 1,032 women were eligible for mammography at a participating center, and 628 (61%) underwent a mammogram at no cost to them as instructed. Twenty four (4%) had definite abnormalities which led to biopsy and seven (1%) of them had malignant lesions. The medical community organized to provide breast cancer screening and follow-up with low-cost mammography.
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Johnston H, Reisz G. Changing spectrum of hemoptysis. Underlying causes in 148 patients undergoing diagnostic flexible fiberoptic bronchoscopy. ARCHIVES OF INTERNAL MEDICINE 1989; 149:1666-8. [PMID: 2742442 DOI: 10.1001/archinte.149.7.1666] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A retrospective study to examine the underlying causes of hemoptysis in patients undergoing diagnostic bronchoscopy was conducted. We found hemoptysis to be caused by bronchitis in 55 (37%) of 148, bronchogenic carcinoma in 28 (19%) of 148, tuberculosis in 10 (7%) of 148, and bronchiectasis in 1 (1%) of 148 patients. Compared with previous studies, it appears that hemoptysis is less likely to be caused by bronchiectasis or tuberculosis while hemoptysis caused by bronchitis has increased proportionately. The rate of occurrence of hemoptysis caused by bronchogenic carcinoma has not changed significantly. All patients with underlying bronchogenic carcinoma had a positive smoking history and abnormal chest roentgenogram. The rate of hemoptysis was not a good indicator of the underlying disease.
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March JS, Johnston H, Greist JH. Obsessive-compulsive disorder. Am Fam Physician 1989; 39:175-82. [PMID: 2497627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Patients with obsessive-compulsive disorder complain of anxiety-producing intrusive thoughts and/or perform repetitive, anxiety-reducing rituals. A combination of behavior therapy and drug therapy is generally beneficial in this relatively common disorder. Behavior therapy consists of exposing patients to anxiety-provoking situations and helping them avoid ritualistic responses. Drug therapy appears to work by blocking serotonin reuptake in the brain.
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Henderson SA, Graham HK, Mollan RA, Riddoch C, Sheridan B, Johnston H. Calcium homeostasis and exercise. INTERNATIONAL ORTHOPAEDICS 1989; 13:69-73. [PMID: 2722319 DOI: 10.1007/bf00266727] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Calcium homeostasis is altered by strenuous physical exercise. The mechanism is unclear. Our study was designed to investigate this relationship, particularly any associated changes in the calcium regulating hormones. Six subjects carried out a strenuous exercise programme for 10 min on a bicycle ergometer. Blood samples were analysed for ionized calcium, total calcium, calcitonin and pH. Plasma parathormone was assayed using a new and very sensitive N-terminal assay. Serum ionized calcium was significantly elevated by exercise at 50% of maximum aerobic capacity (VO2 max). The rise persisted until the late recovery phase, when it fell significantly below resting levels. Plasma parathormone levels were initially depressed by moderate exercise (50% VO2 max.) but were significantly elevated during and immediately after severe exercise. Our results suggest that exercise stimulates the hormonal, osteolytic influences acting on the skeleton, with increases in plasma parathormone and mobilisation of calcium stores. These changes may provide a supply of raw material allowing the osteogenic mechanical forces initiated by exercise to produce a positive skeletal balance. In view of the possible relevance of these findings to the understanding and management of osteoporosis we feel that this area merits further study.
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Meara J, Mayon-White R, Johnston H. Salmonellosis in a psychogeriatric ward: problems of infection control. J Hosp Infect 1988; 11:86-90. [PMID: 2895143 DOI: 10.1016/0195-6701(88)90044-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Johnston H, Majewski H, Musgrave IF. Involvement of cyclic nucleotides in prejunctional modulation of noradrenaline release in mouse atria. Br J Pharmacol 1987; 91:773-81. [PMID: 3664078 PMCID: PMC1853579 DOI: 10.1111/j.1476-5381.1987.tb11275.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
1 In mouse isolated atria previously incubated with [3H]-noradrenaline, 8-bromo-cyclic AMP (3-270 microM) produced a concentration-dependent increase in the fractional stimulation-induced outflow of radioactivity. 8-Bromo-cyclic GMP induced a lesser increase in the stimulation-induced outflow. 2 The phosphodiesterase inhibitors: M&B 22948 (90 microM); ICI 63197 (30 and 90 microM) and 3-isobutyl-1-methylxanthine (90 microM) increased the fractional stimulation-induced outflow. Together these results indicate that cyclic AMP may have a modulatory effect on noradrenaline release. 3 The inhibition of the stimulation-induced outflow produced by clonidine (0.03 microM) and its facilitation produced by phentolamine (1 microM) were unaltered in the presence of 8-bromo-cyclic AMP (90 microM). However, in the presence of 8-bromo-cyclic AMP (270 microM), the facilitatory effect of phentolamine was enhanced, but the inhibitory effect of clonidine (0.03 microM) was unaltered. In the presence of ICI 63197 (30 microM) the inhibitory effect of clonidine (0.03 microM) was unaltered, but the facilitatory effect of phentolamine (1 microM) was slightly enhanced. 4 Isoprenaline (0.003-0.1 microM) enhanced the fractional stimulation-induced outflow, an effect blocked by propranolol (0.1 microM). In the presence of 8-bromo-cyclic AMP (90 microM), the facilitatory effect of isoprenaline (0.01 microM) was blocked. In the presence of ICI 63197 (30 microM) the facilitatory effect of isoprenaline (0.003 microM) was potentiated. 5 These results suggest that whereas beta-adrenoceptor-mediated enhancement of noradrenaline release is linked to the stimulation of adenylate cyclase and enhanced formation of cyclic AMP, alpha-adrenoceptor-mediated inhibition of noradrenaline release is not linked to inhibition of adenylate cyclase activity.
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Tallman MS, McGuffin RW, Higano CS, Starkebaum G, Collins SJ, Johnston H, Singer JW, Perry DJ, Kunath A. Bone marrow transplantation in a patient with myelodysplasia associated with diffuse eosinophilic fasciitis. Am J Hematol 1987; 24:93-9. [PMID: 3541583 DOI: 10.1002/ajh.2830240112] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A 34-year-old man with diffuse eosinophilic fasciitis and a hypocellular myelodysplastic syndrome underwent marrow transplantation from an HLA-identical brother. Prompt hematopoietic reconstitution was observed, strongly suggesting that the marrow hypocellularity was caused by neither a serum inhibitory factor nor a microenvironmental disorder. The patient died of disseminated cytomegalovirus infection too early to evaluate the impact of hematopoietic reconstitution on the eosinophilic fasciitis. Nevertheless, marrow transplantation may offer a therapeutic option for those patients with this disorder who develop severe hematopoietic dysfunction and who have a suitable marrow donor.
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Barry J, Tran Z, Weltman A, Johnston H. THE EFFECTS OF TRAINING ON THE LACTATE THRESHOLD IN INSULIN-DEPENDENT DIABETIC MEN. Med Sci Sports Exerc 1986. [DOI: 10.1249/00005768-198604001-00351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Markley LD, Tong YC, Dulworth JK, Steward DL, Goralski CT, Johnston H, Wood SG, Vinogradoff AP, Bargar TM. Antipicornavirus activity of substituted phenoxybenzenes and phenoxypyridines. J Med Chem 1986; 29:427-33. [PMID: 3005578 DOI: 10.1021/jm00153a020] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Phenoxybenzenes and phenoxypyridines were prepared and tested for the effect of substituents on antipicornavirus activity. The most active compound, 2-(3,4-dichlorophenoxy)-5-nitrobenzonitrile (8), demonstrated broad-spectrum antipicornavirus activity. Compound 8 and several analogues each given orally prior to and during infection protected mice against an otherwise lethal challenge with coxsackievirus A21.
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Johnston H, Majewski H. Prejunctional beta-adrenoceptors in rabbit pulmonary artery and mouse atria: effect of alpha-adrenoceptor blockade and phosphodiesterase inhibition. Br J Pharmacol 1986; 87:553-62. [PMID: 2879584 PMCID: PMC1916557 DOI: 10.1111/j.1476-5381.1986.tb10197.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In rabbit isolated pulmonary artery previously incubated with [3H]-noradrenaline, isoprenaline (0.3 microM) had no effect on the stimulation-induced outflow of radioactivity. However, if the phosphodiesterase inhibitor ICI 63,197 (30 microM) or the alpha-adrenoceptor blocker phentolamine (1 microM) was present, then isoprenaline significantly enhanced the stimulation-induced outflow, an effect blocked by propranolol (0.1 microM). ICI 63,197 (30 microM) but not phentolamine significantly enhanced the stimulation-induced outflow of radioactivity. In mouse isolated atria previously incubated with [3H]-noradrenaline and stimulated at a frequency of 10 Hz, isoprenaline had no effect on the stimulation-induced outflow of radioactivity; this is in contrast to its release-enhancing effects at stimulation frequencies of 4 Hz and 2 Hz. The facilitation of stimulation-induced outflow by isoprenaline at 4 Hz was blocked by propranolol (0.08 microM) which, by itself, had no effect on the stimulation-induced outflow. At a stimulation frequency of 2 Hz in mouse atria the facilitatory effect of isoprenaline (0.01 microM) was significantly greater in the presence of ICI 63,197 (30 microM) which, by itself, had no effect on the stimulation-induced outflow. Similarly, the facilitatory effect of isoprenaline was significantly greater in the presence of phentolamine (1 microM) but, in this case, phentolamine significantly enhanced the stimulation-induced outflow. These results suggest that facilitatory prejunctional beta-adrenoceptors are present in both rabbit pulmonary artery and mouse atria. The effects of the phosphodiesterase inhibitor ICI 63,197 suggest that they are linked to adenylate cyclase in both tissues and we propose that the ability of phentolamine to facilitate the release and enhance the effect of isoprenaline may be due to the blockade of alpha-adrenoceptor inhibition of adenylate cyclase. This latter proposition needs further investigation.
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Kennedy L, Atkinson A, Johnston H, Sheridan B, Hadden D. Serum Cortisol Concentrations During Low Dose Dexamethasone Suppression Test to Screen for Cushing’s Syndrome. J Urol 1985. [DOI: 10.1016/s0022-5347(17)49197-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kennedy L, Hadden D, Atkinson B, Sheridan B, Johnston H. Serum cortisol concentrations during low dose dexamethasone suppression test to screen for Cushing's syndrome. West J Med 1985. [DOI: 10.1136/bmj.290.6462.158-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kennedy L, Atkinson AB, Johnston H, Sheridan B, Hadden DR. Serum cortisol concentrations during low dose dexamethasone suppression test to screen for Cushing's syndrome. BMJ : BRITISH MEDICAL JOURNAL 1984; 289:1188-91. [PMID: 6437479 PMCID: PMC1443333 DOI: 10.1136/bmj.289.6453.1188] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Forty four subjects (23 obese controls, 11 patients with possible Cushing's syndrome, and 10 patients with definite Cushing's syndrome) underwent low dose (0 X 5 mg every six hours for two days) dexamethasone suppression tests during which serum cortisol concentration at 0800 and excretion of urinary free cortisol over 24 hours were measured. Serum cortisol concentration fell to below 60 nmol/1 (2 X 2 micrograms/100 ml) in 31 subjects and remained above 250 nmol/1 (9 X 1 micrograms/100 ml) in the 13 others. Excretion of urinary free cortisol showed a similar response, falling to below 110 nmol (40 micrograms)/24 h in 31 and remaining above 180 nmol (65 micrograms)/24 h in the 13 others. There was complete concordance between the two variables in terms of the pattern of response. Serum cortisol concentration fell to below 60 nmol/1 (2 X 2 micrograms/100 ml) in at least 97% (31 of a possible 32) of subjects without Cushing's syndrome. On the other hand, a serum cortisol concentration of above 250 nmol/1 (9 X 1 micrograms/100 ml) after low dose dexamethasone gave a false positive diagnosis of Cushing's syndrome in at most only one of 13 patients (7 X 7%). Measurement of serum cortisol concentration during the low dose dexamethasone test is simpler than, and as accurate and reliable as, measurements of urinary steroids.
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Johnston H, Rubinowitz MJ. The many faces of mono. THE JOURNAL OF THE KANSAS MEDICAL SOCIETY 1984; 85:115-6, 124. [PMID: 6586925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Moran JR, Vaughan R, Stroop S, Coy S, Johnston H, Greene HL. Concentrations and total daily output of micronutrients in breast milk of mothers delivering preterm: a longitudinal study. J Pediatr Gastroenterol Nutr 1983; 2:629-34. [PMID: 6685761 DOI: 10.1097/00005176-198311000-00010] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The number of preterm infants fed their own mother's milk appears to be increasing as a result of information suggesting certain benefits over milk from human milk banks or proprietary formulas. It is also apparent that the nutritional requirements of term and preterm infants differ. Thus, the finding of various deficiencies in small preterm infants indicates that studies which examine the nutrient content of milk from mothers who deliver prematurely are important to aid in suggesting appropriate supplementation. In order to provide appropriate recommendations, nutrient content must be assayed during the period of exclusive milk feedings. Accordingly, the concentrations and total daily output of breast milk zinc and copper, and vitamins A, C, and E, were examined in a group of 13 mothers delivering at or before 32 weeks gestation. Collections of a total 24-h output were obtained every 7 days for the first 7 weeks after delivery. Concentrations of all micronutrients were similar to those reported previously during the first 5 weeks of lactation. Most striking, however, was the progressive decline in total output as well as concentration of zinc. After the first 2 weeks of lactation, levels of copper and vitamins A, C, and E were not affected by the duration of lactation. There was substantial variation between mothers in daily output of all the micronutrients. The low output of these micronutrients suggests that some attempt should be made at monitoring the mineral and vitamin status of small preterm infants fed exclusively human milk for the first 3 months of life.(ABSTRACT TRUNCATED AT 250 WORDS)
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Goldfarb WB, Bigos TS, Eastman RC, Johnston H, Nishyama RH. Needle biopsy in the assessment and management of hypofunctioning thyroid nodules. Am J Surg 1982; 143:409-12. [PMID: 7072907 DOI: 10.1016/0002-9610(82)90187-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Needle biopsy of hypofunctioning solitary thyroid nodules provides direct diagnostic information which would be otherwise obtainable only by surgery. The technique is safe and cost-effective. It provides a high diagnostic yield. It is also useful in planning surgery and reducing dependence on frozen-section diagnosis, which is often difficult with thyroid nodules. Technical and interpretative precautions are discussed. Of 192 patients undergoing this procedure, a satisfactory specimen was obtained in 95 percent. Needle aspiration biopsy (fine needle) was done in 110 patients with good cytologic correlations. Of 52 glands subsequently excised, carcinoma was present in 22 (42 percent). The preoperative diagnosis had been made in 19 (86 percent) of the latter group. This procedure is recommended for consideration in the assessment and management of hypofunctioning thyroid nodules.
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77
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Goodman RH, Post KD, Molitch ME, Adelman LS, Altemus LR, Johnston H. Eosinophilic granuloma mimicking a pituitary tumor. Neurosurgery 1979; 5:723-5. [PMID: 534084 DOI: 10.1227/00006123-197912000-00015] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The authors present the case report of a patient in whom hypopituitarism, diplopia, and visual field defects were due to eosinophilic granuloma. Radiographic studies were suggestive of a pituitary tumor and subsequent histological evaluation showed replacement of the anterior pituitary by histiocytic cells. Eosinophilic granuloma should be included in the differential diagnosis of an intrasellar mass.
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78
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Block MB, Johnston H, Kartub MG. Unilateral exophthalmos: an unusual presentation of primary hyperparathyroidism. ARIZONA MEDICINE 1978; 35:785-6. [PMID: 727953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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79
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Abstract
Soil and sea bacteria produce a small amount of nitrous oxide (N(2)O); a small part of this N(2)O is photochemically converted to nitric oxide (NO) in the stratosphere. This process has recently been shown to be the principal source of the active oxides of nitrogen (NO and NO(2)) in the stratosphere. The active oxides of nitrogen catalytically destroy ozone, and NO and NO(2) appear to be a principal factor in the natural ozone balance. Stratospheric ozone is the only effective shield for the surface of the Earth against the harsh ultraviolet radiation between 300 and 250 nm. Thus, soil bacteria indirectly control the intensity of ultraviolet radiation reaching the Earth's surface. This subcycle of the major nitrogen cycle involves a relatively small amount of nitric oxide, estimated to be between 0.26 and 1.2 x 10(9) kg of NO per year on a worldwide basis. A recent estimate of the future nitric oxide emission in the stratosphere by the Concord supersonic transport is 0.37 x 10(9) kg/year on a world-wide basis, which is similar to the amount estimated from the natural source.
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80
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Johnston H. Reduction of Stratospheric Ozone by Nitrogen Oxide Catalysts from Supersonic Transport Exhaust. Science 1971; 173:517-22. [PMID: 17738433 DOI: 10.1126/science.173.3996.517] [Citation(s) in RCA: 719] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Although a great deal of attention has been given to the role of water vapor from supersonic transport (SST) exhaust in the stratosphere, oxides of nitrogen from SST exhaust pose a much greater threat to the ozone shield than does an increase in water. The projected increase in stratospheric oxides of nitrogen could reduce the ozone shield by about a factor of 2, thus permitting the harsh radiation below 300 nanometers to permeate the lower atmosphere.
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81
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Neuburger C, Johnston H. Continuing education in diabetes. A report of the North Dakota nutrition and diabetes workshops. BEDSIDE NURSE 1970; 3:14-9. [PMID: 5203418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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82
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Hunter RJ, Pinkerton JH, Johnston H. Serum placental alkaline phosphatase in normal pregnancy and preeclampsia. Obstet Gynecol 1970; 36:536-46. [PMID: 5506461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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83
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Clarke RS, Johnston H, Sheridan B. The influence of anaesthesia and surgery on plasma cortisol, insulin and free fatty acids. Br J Anaesth 1970; 42:295-9. [PMID: 5427262 DOI: 10.1093/bja/42.4.295] [Citation(s) in RCA: 82] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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