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Roeckner JT, Pressman K, Odibo L, Duncan JR, Odibo AO. Reply. Ultrasound Obstet Gynecol 2021; 58:494-495. [PMID: 34468058 DOI: 10.1002/uog.23748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Affiliation(s)
- J T Roeckner
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - K Pressman
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - L Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - J R Duncan
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - A O Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
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Roeckner JT, Pressman K, Odibo L, Duncan JR, Odibo AO. Reply. Ultrasound Obstet Gynecol 2021; 58:329-330. [PMID: 34346120 DOI: 10.1002/uog.23721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Affiliation(s)
- J T Roeckner
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - K Pressman
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - L Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - J R Duncan
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - A O Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
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Roeckner JT, Pressman K, Odibo L, Duncan JR, Odibo AO. Outcome-based comparison of SMFM and ISUOG definitions of fetal growth restriction. Ultrasound Obstet Gynecol 2021; 57:925-930. [PMID: 33798274 DOI: 10.1002/uog.23638] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 02/15/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
OBJECTIVE The recent international guidelines by the Society for Maternal-Fetal Medicine (SMFM) and the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) differ in their definitions of fetal growth restriction (FGR). Our aim was to compare the performance of the two definitions in predicting neonatal small-for-gestational age (SGA) and composite adverse neonatal outcome (ANO). METHODS This was a secondary analysis of data from a prospective study of women referred for fetal growth ultrasound examination between 26 + 0 and 36 + 6 weeks' gestation. The SMFM and ISUOG guidelines were used to define pregnancies with FGR. The SMFM definition of FGR is estimated fetal weight (EFW) or abdominal circumference (AC) < 10th percentile. The ISUOG-FGR definition follows the Delphi consensus criteria and includes either EFW or AC < 3rd percentile or EFW or AC < 10th percentile combined with abnormal Doppler findings or a decrease in growth centiles. The primary outcome was the prediction of neonatal SGA, defined as birth weight < 10th percentile, and a composite of ANO, which was defined as one or more of: Grade-III or -IV intraventricular hemorrhage, respiratory distress syndrome, neonatal death, cord blood pH < 7.1, seizures and admission to the neonatal intensive care unit. Test characteristics (sensitivity, specificity, positive predictive value (PPV), negative predictive value and positive (LR+) and negative likelihood ratios) and area under the receiver-operating-characteristics curve were determined. The association between FGR detected by each definition and selected adverse outcomes was assessed using logistic regression analysis. RESULTS Of the 1054 pregnancies that met the inclusion criteria, 137 (13.0%) and 55 (5.2%) were defined as having FGR by the SMFM and ISUOG definitions, respectively. Composite ANO and SGA neonate each occurred in 139 (13.2%) pregnancies. For the prediction of neonatal SGA, the SMFM-FGR definition had a higher sensitivity (54.7%) than did the ISUOG definition (28.8%). The ISUOG-FGR definition had higher specificity (98.4% vs 93.3%), LR+ (18.0 vs 8.2) and PPV (72.7% vs 55.5%) than did the SMFM definition for the prediction of a SGA neonate. The SMFM- and ISUOG-FGR definitions had similarly poor performance in predicting composite ANO, with sensitivities of 15.1% and 10.1%, respectively. CONCLUSIONS The SMFM definition of FGR is associated with a higher detection rate for SGA neonates but at the cost of some reduction in specificity. The ISUOG-FGR definition has a higher specificity, LR+ and PPV for the prediction of neonatal SGA. Both definitions of FGR performed poorly in predicting a composite ANO. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- J T Roeckner
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - K Pressman
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - L Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - J R Duncan
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - A O Odibo
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
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Crossin R, Lawrence AJ, Andrews ZB, Churilov L, Duncan JR. Growth changes after inhalant abuse and toluene exposure: A systematic review and meta-analysis of human and animal studies. Hum Exp Toxicol 2018; 38:157-172. [PMID: 30062923 DOI: 10.1177/0960327118792064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Inhalant abuse is a significant public health issue, particularly for adolescents, the predominant group of inhalant users. Adolescence is a critical growth period, and inhalant abuse has been associated with growth impairments, including reduced body weight and height. However, the extent to which inhalant abuse affects growth remains unquantified, and potential moderators remain unknown. To address this knowledge gap, a systematic review and meta-analysis of clinical human and preclinical animal studies utilizing toluene exposure (the primary solvent in abused products) was conducted. Five-hundred and sixty-nine studies were screened; 31 met inclusion criteria, yielding 64 toluene-control comparisons for body weight and 6 comparisons for height. Toluene exposure was negatively associated with body weight ( d = -0.73) and height ( d = -0.69). Concentration of inhaled toluene, but not duration, moderated the effect of toluene exposure on body weight, with more severe impairments at higher concentrations. Differences in effect size for body weight were observed for study characteristic subgroups including sex, age at first exposure, administration route and species. However, these findings should be interpreted cautiously due to low study numbers. Growth impairments, particularly during adolescence, can cause long-term health consequences. These effects on growth are therefore an important clinical outcome for individuals with a history of inhalant abuse.
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Affiliation(s)
- R Crossin
- 1 Addiction Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Victoria, Australia.,2 Eastern Health Clinical School, Monash University, Clayton, Victoria, Australia
| | - A J Lawrence
- 1 Addiction Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Victoria, Australia.,3 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Victoria, Australia
| | - Z B Andrews
- 4 Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - L Churilov
- 3 Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Victoria, Australia
| | - J R Duncan
- 1 Addiction Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Victoria, Australia.,5 School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
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Kaffenberger BH, Zhang E, Duncan JR, Jaglowski S, Klisovic RB, Devine SM, Wong HK, Gru AA. Endothelial chimerism in chronic sclerotic-type chronic graft-versus-host disease (GVHD) and GVHD-associated angiomatosis. Br J Dermatol 2016; 175:782-4. [PMID: 26875995 DOI: 10.1111/bjd.14484] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2016] [Indexed: 01/09/2023]
Abstract
Graft-versus-host disease-associated angiomatosis (GVHD-AA) is an uncommon manifestation of chronic GVHD consisting of friable vascular proliferations. Using fluorescence in situ hybridization, we demonstrate the presence of donor-derived endothelial cells within areas of GVHD-AA. This is the first documented occurrence of a benign neoplastic growth in relationship to a form of chronic GVHD.
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Affiliation(s)
- B H Kaffenberger
- Division of Dermatology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A.
| | - E Zhang
- The Ohio State University College of Medicine, Columbus, OH, U.S.A
| | - J R Duncan
- The Ohio State University College of Medicine, Columbus, OH, U.S.A
| | - S Jaglowski
- Division of Hematology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A
| | - R B Klisovic
- Division of Hematology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A
| | - S M Devine
- Division of Hematology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A
| | - H K Wong
- Division of Dermatology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A
| | - A A Gru
- Division of Dermatology, Wexner Medical Center at Ohio State University, Gahanna, OH, 43440, U.S.A
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Dick ALW, Simpson A, Qama A, Andrews Z, Lawrence AJ, Duncan JR. Chronic intermittent toluene inhalation in adolescent rats results in metabolic dysfunction with altered glucose homeostasis. Br J Pharmacol 2015; 172:5174-87. [PMID: 26282596 DOI: 10.1111/bph.13284] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 08/09/2015] [Accepted: 08/10/2015] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Abuse of toluene-containing inhalants is an increasing public health problem, especially among adolescents. Abuse during adolescence is associated with emaciation, while industrial exposure leads to altered glycaemic control suggesting metabolic instability. However, the relationship between adolescent inhalant abuse and metabolic dysfunction remains unknown. EXPERIMENTAL APPROACH To model human abuse patterns, we exposed male adolescent Wistar rats [postnatal day (PND) 27] to chronic intermittent inhaled toluene (CIT, 10,000 ppm) or air (control) for 1 h·day(-1) , three times a week for 4 weeks. Feeding and body composition were monitored. After 4 weeks, circulating metabolic hormone concentrations and responses to a glucose tolerance test (GTT) were measured. Dietary preference was measured by giving animals access to either a 'western diet' plus standard chow (WC + SC) or standard chow alone during 4 weeks of abstinence. Metabolic hormones and GTT were subsequently measured. KEY RESULTS Adolescent CIT exposure significantly retarded weight gain, altered body composition, circulating metabolic hormones and responses to a GTT. While reduced body weight persisted, responses to a GTT and circulating hormones appeared to normalize for animals on standard chow following abstinence. In CIT-exposed WC + SC rats, we observed impaired glucose tolerance associated with altered metabolic hormones. Analysis of hypothalamic genes revealed differential expression profiles in CIT-exposed rats following both the exposure period and abstinence, suggesting a central contribution to inhalant-induced metabolic dysfunction. CONCLUSION AND IMPLICATIONS CIT exposure during adolescence has long-term effects on metabolic function, which may increase the risk of disorders related to energy balance and glycaemic control.
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Affiliation(s)
- A L W Dick
- Division of Behavioural Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Vic., Australia.,Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - A Simpson
- Division of Behavioural Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Vic., Australia
| | - A Qama
- Division of Behavioural Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Vic., Australia
| | - Z Andrews
- Department of Physiology, Monash University, Clayton, Vic., Australia
| | - A J Lawrence
- Division of Behavioural Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Vic., Australia
| | - J R Duncan
- Division of Behavioural Neuroscience, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Vic., Australia.,Department Anatomy and Neuroscience, University of Melbourne, Melbourne, Vic., Australia
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Mack CL, Wilhelmi B, Duncan JR, Burgess JE. Biosorptive recovery of platinum from platinum group metal refining wastewaters by immobilised Saccharomyces cerevisiae. Water Sci Technol 2011; 63:149-155. [PMID: 21245567 DOI: 10.2166/wst.2011.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The process of platinum group metal (PGM) refining can be up to 99.99% efficient at best, and although it may seem small, the amount of valuable metal lost to waste streams is appreciable enough to warrant recovery. The method currently used to remove entrained metal ions from refinery wastewaters, chemical precipitation, is not effective for selective recovery of PGMs. The yeast Saccharomyces cerevisiae has been found capable of sorbing numerous precious and base metals, and is a cheap and abundant source of biomass. In this investigation, S. cerevisiae was immobilised using polyethyleneimine and glutaraldehyde to produce a suitable sorbent, capable of high platinum uptake (150-170 mg/g) at low pH (<2). The sorption mechanism was found to be a chemical reaction, which made effective desorption impossible. When applied to PGM refinery wastewater, two key wastewater characteristics limited the success of the sorption process; high inorganic ion content and complex speciation of the platinum ions. The results proved the concept principle of platinum recovery by immobilised yeast biosorption and indicated that a more detailed understanding of the platinum speciation within the wastewater is required before biosorption can be applied. Overall, the sorption of platinum by the S. cerevisiae sorbent was demonstrated to be highly effective in principle, but the complexity of the wastewater requires that pretreatment steps be taken before the successful application of this process to industrial wastewater.
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Affiliation(s)
- C L Mack
- Department of Biochemistry Microbiology and Biotechnology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa
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Moore BA, Mack C, Duncan JR, Burgess JE. Metal–biomass interactions: a comparison of visualisation techniques available in South Africa. S AFR J SCI 2010. [DOI: 10.4102/sajs.v105i3/4.61] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Jenkins JT, Duncan JR, Hole D, O'Dwyer PJ, McGregor JR. Malignant disease in peptic ulcer surgery patients after long term follow-up: A cohort study of 1992 patients. Eur J Surg Oncol 2007; 33:706-12. [PMID: 17207958 DOI: 10.1016/j.ejso.2006.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 11/10/2006] [Indexed: 01/29/2023] Open
Abstract
AIMS To assess the effect of previous peptic ulcer surgery on subsequent malignant events, in particular in relation to previous vagotomy, a historical cohort study was conducted. METHODS All patients undergoing surgery for peptic ulcer disease with accurate follow-up data at a large peptic ulcer clinic in the Western Infirmary, Glasgow, from 1965 to 1983 were assessed. All cancer events and specific cancer events (gastric, bronchial, laryngeal, colorectal, bladder, breast, prostate, pancreas, kidney, oesophageal cancers) were determined as outcome measures and expressed as standardised incidence ratio (SIR). RESULTS Vagotomy and drainage accounted for 67% of all procedures for peptic ulcer disease. Eighty-three percent were habitual smokers. For all peptic ulcer surgery patients, the SIR for all cancer events was 0.86. For specific cancers, the SIRs were bronchial cancer (SIR 1.13); laryngeal cancer (SIR 2.17), colorectal cancer (SIR 0.67). For vagotomised patients the risk of gastric cancer was significantly elevated (SIR 1.50). CONCLUSIONS An excess of cancers attributable to smoking have been found in peptic ulcer surgery patients. Vagotomised patients have a higher risk of gastric cancer after long term follow-up. This finding may have implications for screening and the safety of long term acid suppression with agents such as proton pump inhibitors.
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Affiliation(s)
- J T Jenkins
- Department of Surgery, Crosshouse Hospital, Kilmarnock, UK.
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Abstract
Biosorption has emerged as a low-cost and often low-tech option for removal or recovery of base metals from aqueous wastes. The conditions under which precious metals such as gold, platinum and palladium are sorbed by biomass are often very different to those under which base metals are sorbed. This, coupled with the increasingly high demand for precious metals, drives the increase in research into efficient recovery of precious metal ions from all waste material, especially refining wastewaters. Common biosorbents for precious metal ions include various derivatives of chitosan, as well as other compounds with relatively high surface amine functional group content. This is generally due to the ability of the positively charged amine groups to attract anionic precious metal ions at low pH. Recent research regarding the biosorption of some precious metals is reviewed here, with emphasis on the effects of the biosorption environment and the biosorption mechanisms identified.
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Affiliation(s)
- C Mack
- Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, South Africa
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11
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Umali LJ, Duncan JR, Burgess JE. Performance of Dead Azolla filiculoides Biomass in Biosorption of Au from Wastewater. Biotechnol Lett 2006; 28:45-50. [PMID: 16369874 DOI: 10.1007/s10529-005-9686-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Revised: 10/10/2005] [Accepted: 10/26/2005] [Indexed: 10/25/2022]
Abstract
Dried milled biomass of Azolla filiculoides removed up to 98.2% of gold from wastewater from a gold plating factory containing 5 mg gold/l in solution in batch biosorption. The gold uptake capacity of the biomass was 98 mg/g. Whole dried biomass used in a continuous flow column removed up to 100% of gold from diluted wastewater. A similar column was linked to a sulphide precipitation process to provide a two-step system which was able to remove 98% of gold from undiluted wastewater containing 41 mg Au/l. The lifetime of the column was five days.
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Affiliation(s)
- L J Umali
- Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, 6140, Grahamstown, South Africa
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Abstract
Intrauterine infection has been associated with fetal brain injury and preterm birth. We have recently shown that repeated exposure to bacterial endotoxin leads to hypoxia and brain injury in the preterm ovine fetus and we considered it possible that endotoxin could also damage the placenta. Our aim therefore was to assess placental structure following repeated exposure to endotoxin. Endotoxin was administered on 3-5 occasions (1 microg/kg, i.v.) over 5 days from 95-99 days of gestation (term approximately 147 days) to 6 fetal sheep and placental structure assessed at 105 days. In LPS-exposed animals there was a 17 per cent reduction (P<0.05) in placental weight and the average cross-sectional area of placentomes was reduced (P<0.05) by 20 per cent. In addition, all LPS-exposed placentae showed significant injury as evidenced by calcium deposits associated with areas of infarcted tissue. We conclude that repeated endotoxin exposure results in damage to the placenta which could lead to persistent alterations in placental exchange function.
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Affiliation(s)
- J R Duncan
- Department of Anatomy & Cell Biology, University of Melbourne, 3010, Victoria, Australia.
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Abstract
Primary aortoenteric fistula is such a rare condition that even specialist vascular surgeons may not encounter one in their lifetime practice. Any hope of survival depends upon prompt diagnosis and surgical treatment. We present our experience of one such case, particularly the difficulties encountered in confirming the diagnosis, and go on to review the literature on the subject. Both our experience and that reported by previous authors would suggest that specialized investigations such as computed tomography, contrast angiography, radionuclide scintigraphy, and gastrointestinal endoscopy have only a limited contribution to make in confirming the diagnosis of primary aortoenteric fistula. The diagnosis should be considered in any patient with gastrointestinal blood loss and an abdominal aortic aneurysm. Specialized investigations should not be relied upon to confirm or refute the diagnosis. Any prospect of survival is dependant upon prompt diagnosis and surgical intervention. The latter is only achieved by a high index of clinical suspicion.
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Affiliation(s)
- J R Duncan
- Department of Peripheral Vascular Surgery, Glasgow Royal Infirmary, North Glasgow Hospitals University NHS Trust, Glasgow, Scotland, UK.
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Baskett JJ, Wood PC, Broad JB, Duncan JR, English J, Arendt J. Melatonin in older people with age-related sleep maintenance problems: a comparison with age matched normal sleepers. Sleep 2001; 24:418-24. [PMID: 11403526 DOI: 10.1093/sleep/24.4.418] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
STUDY OBJECTIVES To determine whether older people with age-related sleep maintenance problems have significantly lower melatonin levels than comparable normal sleepers. DESIGN Case-control study. SETTING A largely urban population, Auckland, New Zealand. PARTICIPANTS People over the age of 65 years, who either slept normally, or had age-related sleep maintenance problems. Participants were recruited through media advertising, and local interest groups. Initial screening was by mail (Pittsburgh Sleep Quality Index), followed by interviews at a hospital day clinic. Exclusions included those with depression, cognitive impairment, medical and/or environmental problems which might impair sleep. INTERVENTIONS N/A. MEASUREMENTS AND RESULTS A metabolite of plasma melatonin, 6-sulphatoxymelatonin (aMT6s) was measured in the urine of 57 normal sleepers, and 53 people with age-related problems over 24 hours in three aliquots: 12:00-19:00h, 19:00-07:00h, 07:00-12:00h. There were clear differences in self reported quality of sleep but no difference in mean aMT6s 24 hour or total night excretory levels, or night/day ratios. CONCLUSIONS Older people with age-related sleep maintenance problems do not have lower melatonin levels than older people reporting normal sleep.
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Affiliation(s)
- J J Baskett
- Waitemata Health Ltd, Auckland, New Zealand.
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15
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Chakraverty R, Rabin N, Peggs K, Robinson S, Duncan JR, Yong K. Dermatomyositis and sarcoid-like reaction associated with multiple myeloma treated effectively by high-dose chemotherapy and autologous peripheral blood stem cell transplantation. Bone Marrow Transplant 2001; 27:1215-7. [PMID: 11551034 DOI: 10.1038/sj.bmt.1703048] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We report the case of a 46-year-old male who developed dermatomyositis and a sarcoid-like reaction in association with testicular relapse of multiple myeloma. The myositis progressed despite chemotherapy directed at the underlying malignant disorder and immunosuppressive treatment. There was, however, a dramatic and sustained response to high-dose chemotherapy and autologous peripheral blood stem cell transplantation which resulted in resolution of the myopathy and partial resolution of the sarcoid-like reaction. This case report highlights the potential of autologous stem cell transplantation as treatment for para-neoplastic disorders associated with haematological malignancies.
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Affiliation(s)
- R Chakraverty
- Institute of Cancer Studies, University of Birmingham, Edgbaston, UK
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16
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Duncan JR, Anderson CJ, Arano Y. Nuclear translocation of somatostatin analogs. J Nucl Med 2001; 42:529-31. [PMID: 11337534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
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17
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Duncan JR, Cock ML, Harding R, Rees SM. Relation between damage to the placenta and the fetal brain after late-gestation placental embolization and fetal growth restriction in sheep. Am J Obstet Gynecol 2000; 183:1013-22. [PMID: 11035356 DOI: 10.1067/mob.2000.107321] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Our aim was to determine the effects of 30 days of placental insufficiency on fetal brain development and to relate placental damage to the degree of fetal brain injury. STUDY DESIGN Umbilicoplacental embolization was induced from 110 to 140 days of gestation (term, 147 days) in 7 fetal sheep, such that fetal arterial oxygen saturation was maintained at 50% of pre-umbilicoplacental embolization values. Six control fetuses were used. At 140 days the fetal brains and placentas were subjected to structural and histochemical analysis. RESULTS During umbilicoplacental embolization, fetal arterial oxygen saturation, PaO(2), and pH were reduced (P <.05). Thirty days of umbilicoplacental embolization caused a decrease in cross-sectional area of the placentome (P <.05), with 20% of tissue showing damage. All umbilicoplacental embolization fetuses were growth restricted and had brain damage, most prominently in the cerebral white matter. There was no relation between the extent of placental damage and the severity of fetal brain damage. CONCLUSIONS The absence of a correlation between damage to the placenta and fetal brain is likely to be caused by variations between individuals in (1) the amount of placenta that is required to be functionally damaged to achieve the prescribed level of hypoxemia and (2) the response of the fetal brain to that level of hypoxemia.
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Affiliation(s)
- J R Duncan
- Department of Anatomy and Cell Biology, University of Melbourne, Parkville, Victoria, Australia
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Hackett ML, Duncan JR, Anderson CS, Broad JB, Bonita R. Health-related quality of life among long-term survivors of stroke : results from the Auckland Stroke Study, 1991-1992. Stroke 2000; 31:440-7. [PMID: 10657420 DOI: 10.1161/01.str.31.2.440] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The consequences of stroke are a major health concern. This study was conducted to compare the health-related quality of life among long-term survivors of stroke with that of the general population. METHODS Our data are taken from a population-based case-control study of all 6-year survivors of stroke with an age- and sex-matched control population. SF-36 mean scores for cases were compared with raw and standardized control and New Zealand norm mean scores. RESULTS Of the original 1761 registered cases, 639 were still alive at 6-year follow-up, and all of these participated in the study. Case patients were more likely than control subjects to be dependent in all basic activities of daily living. Crude mean scores were lower for women; as age increased; for those living in institutions; when the SF-36 was completed by proxy; and when help was required with the activities of daily living. Cases had statistically lower mean scores than both the control group and New Zealand norms for physical functioning and general health. After standardization for age and sex, no differences were found between cases and controls in mental health and bodily pain. CONCLUSIONS Health-related quality of life appears to be relatively good for the majority of patients 6 years after stroke. Despite significant ongoing physical disability, survivors of stroke appear to adjust well psychologically to their illness.
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Affiliation(s)
- M L Hackett
- Clinical Trials Research Unit, Department of Medicine, The University of Auckland, New Zealand.
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19
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Prasse KW, Mahaffey EA, Duncan JR, Burrow MF. Accuracy of interpretation of microscopic images of cytologic, hematologic, and histologic specimens using a low-resolution desktop video conferencing system. Telemed J 1999; 2:259-66. [PMID: 10165362 DOI: 10.1089/tmj.1.1996.2.259] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To determine the accuracy of interpretation of microscopic images for pathologic study transmitted over Switched-56 lines using a desktop interactive video conferencing system. MATERIALS AND METHODS In subjective studies, two systems were connected using null-modem cables, which allowed evaluation of different bandwidths from 56 kbps to 384 kbps. Objective studies were done with two systems connected at distant sites via paired Switched-56 lines that produced an effective bandwidth of 112 kbps. A video camera mounted on a microscope was attached to the sending system. The resolution of the video image on the video conferencing system was 352 x 288 lines. Cases for cytology, hematology, and histopathology studies were selected from archives; one pathologist transmitted microscopic images, and a second pathologist made interpretations. The three pathologists were Board certified with similar experience that ranged from 20 to 35 years. Categories of interpretations or observations were predetermined for each study to allow the data on agreement between the direct microscopic interpretation or observation and that recorded by the receiving pathologist to be corrected for agreement attributable to chance alone. The results were analyzed using the kappa statistic. RESULTS In the subjective studies, image degradation prevented interpretation while the microscope stage was moved. This problem occurred at all bandwidths tested. Image quality limited microscopic details. Organisms < 1 micron in diameter could not be seen reliably. In objective cytologic studies, overall agreement was recorded on 89 of 99 observations. In the four categories of specimens, observed agreement ranged from 0.778 to 0.958, and kappa was 0.704 to 0.948. For hematology specimens, overall agreement was found on 69 of 80 observations; observed agreement on eight types of nucleated blood cells ranged from 0.5 to 1.0, and kappa was 0.429 to 1.0. Poorer color definition and image quality prevented accurate identification of lymphoblasts and eosinophils in particular. For histologic specimens, overall agreement was obtained on 56 of 66 observations, observed agreement on four categories of histologic change ranged from 0.73 to 0.93, and kappa was 0.47 to 0.9. CONCLUSIONS The desktop interactive video conferencing system, as configured in this study, was unsuitable for making definitive diagnoses from transmitted microscopic images.
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Affiliation(s)
- K W Prasse
- Department of Veterinary Pathology, College of Veterinary Medicine, University of Georgia, Athens, USA
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20
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Rose PD, Boshoff GA, van Hille RP, Wallace LC, Dunn KM, Duncan JR. An integrated algal sulphate reducing high rate ponding process for the treatment of acid mine drainage wastewaters. Biodegradation 1999; 9:247-57. [PMID: 10022068 DOI: 10.1023/a:1008352008353] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Acid mine drainage pollution may be associated with large water volume flows and exceptionally long periods of time over which the drainage may require treatment. While the use and role of sulphate reducing bacteria has been demonstrated in active treatment systems for acid mine drainage remediation, reactor size requirement and the cost and availability of the carbon and electron donor source are factors which constrain process development. Little attention has focussed on the use of waste stabilisation ponding processes for acid mine drainage treatment. Wastewater ponding is a mature technology for the treatment of large water volumes and its use as a basis for appropriate reactor design for acid mine drainage treatment is described including high rates of sulphate reduction and the precipitation of metal sulphides. Together with the co-disposal of organic wastes, algal biomass is generated as an independent carbon source for SRB production. Treatment of tannery effluent in a custom-designed high rate algal ponding process, and its use as a carbon source in the generation and precipitation of metal sulphides, has been demonstrated through piloting to the implementation of a full-scale process. The treatment of both mine drainage and zinc refinery wastewaters are reported. A complementary role for microalgal production in the generation of alkalinity and bioadsorptive removal of metals has been utilised and an Integrated 'Algal Sulphate Reducing Ponding Process for the Treatment of Acidic and Metal Wastewaters' (ASPAM) has been described.
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Affiliation(s)
- P D Rose
- Gold Fields Biotechnology Laboratory, Rhodes University, Grahamstown, South Africa
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21
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Duncan JR, Hicks ME, Cai SR, Brunt EM, Ponder KP. Embolization of portal vein branches induces hepatocyte replication in swine: a potential step in hepatic gene therapy. Radiology 1999; 210:467-77. [PMID: 10207431 DOI: 10.1148/radiology.210.2.r99fe10467] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE To determine whether embolization of portal vein branches would stimulate hepatocyte replication in pigs. MATERIALS AND METHODS The portal vein branches supplying 50%-70% of the liver were embolized in eight pigs by using a combination of coils and polyvinyl alcohol particles. The extent of embolization was assessed at portography in all animals and at computed tomography in one animal. Hepatocyte replication was determined by calculating the percentage of cells that incorporated bromodeoxyuridine into their nuclei. Animals survived up to 35 days after the procedure. RESULTS Embolization of the portal vein branches supplying the left and median lobes caused transient increases of less than 70% in portal vein pressures and of less than 100% in liver enzyme levels. Indocyanine green clearance was measured in two animals and decreased less than 50%. The percentage of replicating hepatocytes in the nonembolized lobe was 0% on day 0, 7% on day 2, 14% on day 7, and 2% on day 12. CONCLUSION Substantial hepatocyte replication occurred 2-7 days after embolization of portal vein branches. Further research will help determine if this procedure can facilitate retroviral transduction in large animals. If successful, the low morbidity of this method may allow its use in humans for gene therapy.
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Affiliation(s)
- J R Duncan
- Mallinckrodt Institute of Radiology, Washington Univ School of Medicine, St Louis, Mo., USA
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22
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Dorshow RB, Bugaj JE, Burleigh BD, Duncan JR, Johnson MA, Jones WB. Noninvasive fluorescence detection of hepatic and renal function. J Biomed Opt 1998; 3:340-345. [PMID: 23015088 DOI: 10.1117/1.429854] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A noninvasive in vivo fluorescence detection scheme was employed to continuously monitor exogenous dye clearance from the vasculature. Differentiation between normal and impaired physiological function in a rat model was demonstrated for both liver and kidney. A fiber optic transmitted light from source to ear; a second fiber optic positioned near the ear transmitted the fluorescent light to a detector system. Two model dye systems were employed in this initial study. Indocyanine green, known to be exclusively cleared from the blood stream by the liver, was excited in vivo with laser light at 780 nm. The fluorescence signal was detected at 830 nm. A characteristic clearance curve of normal hepatic function was obtained. After a partial hepatectomy of the liver, the clearance curve was extended in time, as would be expected from reduced hepatic function. In addition, fluorescein labeled poly-D-lysine, a small polymer predominantly cleared from the blood stream by the kidney, was excited in vivo with laser light at 488 nm. The fluorescence signal was detected at 518 nm. A characteristic clearance curve of normal renal function was obtained. After a bilateral ligation of the kidneys, the clearance curve remained elevated and constant, indicating little if any clearance. Thus, the feasibility of a new noninvasive method for physiological function assessment was established. © 1998 Society of Photo-Optical Instrumentation Engineers.
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23
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Stevens JB, Thoen CO, Rohonczy EB, Tessaro S, Kelly HA, Duncan JR. The immunological response of llamas (Lama glama) following experimental infection with Mycobacterium bovis. Can J Vet Res 1998; 62:102-9. [PMID: 9553708 PMCID: PMC1189455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Llamas were experimentally infected with Mycobacterium bovis in order to evaluate the axillary skin test and the ELISA as diagnostic procedures for tuberculosis in llamas (Lama glama). Six llamas were given a single intratracheal challenge with 1 of 2 doses of a recent field isolate of M. bovis and 2 llamas were left as noninfected controls. This resulted in a progressive disease in some animals with 1 mortality as early as 68 d post-infection (PI). The tuberculin skin test, at the axillary site, was positive in 4 of 5 infected llamas at 80 d PI. At 143 d PI, all 3 surviving lamas were positive, including the one which had not responded at 80 d PI. The application of skin and serological tests throughout the course of this experiment adds support for the need to further evaluate the skin test and its anamnestic effect on serodiagnosis since serological responses were generally not observed in the absence of skin testing or antibiotic treatment. The wide variation in M. bovis antigens recognized by the serological response would indicate that a diagnostic panel should include multiple antigens such as MPB70 and lipoarabinomannan (LAM). While skin testing or serology alone may be of limited value to diagnose tuberculosis in llamas, together they may offer an enhanced potential for immunodiagnosis of tuberculosis.
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Affiliation(s)
- J B Stevens
- Animal Diseases Research Institute, Canadian Food Inspection Agency, Nepean, Ontario
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24
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Bass LA, Lanahan MV, Duncan JR, Erion JL, Srinivasan A, Schmidt MA, Anderson CJ. Identification of the soluble in vivo metabolites of indium-111-diethylenetriaminepentaacetic acid-D-Phe1-octreotide. Bioconjug Chem 1998; 9:192-200. [PMID: 9548534 DOI: 10.1021/bc970158h] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Indium-111-diethylenetriaminepentaacetic Acid-D-phenylalanine-octreotide ([111]In-DTPA-octreotide) is a cyclic eight amino acid somatostatin analogue which is approved for gamma scintigraphy of neuroendocrine tumors. To address the factors that contribute to liver and kidney retention of this radiopharmaceutical, its metabolism was evaluated in normal and tumor-bearing rats. The soluble fractions from nontarget (liver and kidney) and target (tumor, pancreas, adrenals) organ homogenates were analyzed out to 21 h postinjection, and urine was analyzed out to 12 h postinjection. The blood was analyzed at shorter time intervals due to the rapid clearance of (111)In-DTPA-octreotide. Radio-TLC and HPLC were used to analyze organ homogenates, blood, and urine. By TLC, intact (111)In-DTPA-octreotide was resolved from the soluble metabolites, and a similar apparent rate of metabolism was observed in the liver, kidney, tumor, and pancreas with approximately 30% intact (111)In-DTPA-octreotide at 4 h postinjection. In the adrenals, metabolism occurred more slowly with approximately 60% intact (111)In-DTPAoctreotide at 4 h postinjection. At 4 h postinjection, the activity excreted in the urine consisted of 85% intact (111)In-DTPA-octreotide. HPLC provided resolution of the individual extractable metabolites. In an attempt to identify these metabolites, two DTPA-amino acid sequences were synthesized: DTPA-D-Phe-Cys and DTPA-D-Phe. Under the conditions used for metabolite analysis, (111)In-DTPA-D-Phe-Cys-OH eluted at 14.6 min and (111)In-DTPA-D-Phe-OH eluted at 7.0 min. Each of these standard sequences was combined with the soluble portion of the organ homogenate and was shown by HPLC to coelute with the metabolites. These data suggest that (111)In-DTPA-octreotide was initially degraded to (111)In-DTPA-D-Phe-Cys-OH and (111)In-DTPA-D-Phe-OH. The (111)In-DTPA-D-Phe-Cys-OH was further degraded to (111)In-DTPA-D-Phe-OH, which appeared to be the final metabolite that was extracted from the organs. From these results, it can be concluded that at longer time points (> 2 h postinjection) a significant amount of (111)In was retained in nontarget organs as (111)In-DTPA-D-Phe-OH and (111)In-DTPA-D-Phe-Cys-OH and not as intact (111)In-DTPA-octreotide.
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Affiliation(s)
- L A Bass
- Division of Radiological Sciences, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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25
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Abstract
RATIONALE AND OBJECTIVES The American Association of Academic Chief Residents in Radiology annually surveys residency programs on a variety of issues related to residency training. The survey results allow individual programs to compare features of their programs with national averages and to gauge trends in radiology residency training. MATERIALS AND METHODS Questionnaires were mailed to the chief residents in 180 accredited radiology residency programs in the United States. A variety of demographic and common-interest questions were asked. The 1997 survey focused on American Board of Radiology (ABR) examination preparation, residency curriculum, and socioeconomic issues relevant to graduating radiology residents. RESULTS Completed surveys from 73 programs (41%) were returned. Areas of curriculum concern among chief residents reflected primarily current turf issues. A higher than expected percentage of residents considered their training to be inadequate in nonneurologic magnetic resonance imaging and chest, musculoskeletal, and genitourinary radiology. Job security is a major emerging concern for radiology residents who are considering careers in private practice. The practice of remembering and transcribing questions from the ABR written examination is common, and these questions are a valued resource in preparing for the diagnostic section of the written examination. Most residents attend a commercial review course before the oral examination, and the majority of programs also provide internal review courses. CONCLUSION A higher than expected percentage of chief residents expressed concern regarding training in subspecialties of radiology that are neither areas of turf dispute nor areas where certificate of additional qualification examinations are offered. Radiology programs and residents expend substantial resources on preparation for the ABR examinations in addition to the usual 4-year curriculum. The most valued resource for the diagnostic section of the examination is almost certainly not equally available. Radiology residents are increasingly concerned about future job security.
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Affiliation(s)
- D V Heck
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
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26
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Abstract
Malignant murine melanoma (BL6-F10) cells convert arachidonic acid primarily to PGD2, PGF2alpha, PGE2, PGI2 in descending order of magnitude. Supplementation with 1-10 microg/ml vitamin E succinate resulted in a significant (P < or = 0.05) decrease in PGD2 levels at vitamin concentrations of 3, 5, 7 and 10 microg/ml respectively, while PGF2alpha levels were significantly decreased at 1, 3, 5 (P < or = 0.05), 7 and 10 microg/ml (P < or = 0.01) vitamin E succinate. BL6-F10 cells supplemented with 7 and 10 microg/ml vitamin E succinate showed a marked increase in PGE2 levels with a significant increase occurring at 10 microg/ml (P < or = 0.025). PGI2 levels followed a similar trend to PGE2 with a significant increase (P < or = 0.05) occurring at 10 microg/ml.
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Affiliation(s)
- P Ottino
- Department of Biochemistry and Microbiology, Rhodes University, J Grahamstown, South Africa
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27
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Duncan JR, Behr TM, DeNardo SJ. Intracellular fate of radiometals. J Nucl Med 1997; 38:829. [PMID: 9170459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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Abstract
Auto immune haemolytic anaemia has been described in association with a variety of hepatotropic viruses, in particular cytomegalovirus, Epstein-Barr virus and hepatitis B. There is a well-recognized association between chronic active hepatitis and auto immune haemolytic anaemia. We present the first reported case of acute hepatitis A which resulted in a fall in haemoglobin concentration from 14.6 to 4.5 g/dl due to an acute haemolytic anaemia with an associated rise in bilirubin from 149 to 960 mumol/l.
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Affiliation(s)
- J A Tibble
- Department of Gastroenterology, Royal Sussex County Hospital, Brighton, UK
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29
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Duncan JR, Stephenson MT, Wu HP, Anderson CJ. Indium-111-diethylenetriaminepentaacetic acid-octreotide is delivered in vivo to pancreatic, tumor cell, renal, and hepatocyte lysosomes. Cancer Res 1997; 57:659-71. [PMID: 9044843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
To better understand the factors that govern the target-to-background ratios of 111In-diethylenetriaminepentaacetic acid (DTPA) polypeptides, we studied 111In-DTPA-octreotide and a model nontargeted compound, 111In-DTPA-poly(D)lysine-biotin. We evaluated the fate of 111In-DTPA-octreotide after it localizes in somatostatin receptor-positive tissues and sought to determine why such a large fraction of these and other 111In-DTPA-polypeptides accumulate in the liver and kidneys. Biodistribution studies in rats with an implanted pancreatic adenocarcinoma demonstrated rapid accumulation of 111In-DTPA-octreotide in the pancreas and tumor. Indium-111 also accumulated in the liver and kidneys. Subcellular fractionation of the liver, kidneys, tumor, and pancreas showed that the majority of the radioactivity copurified with lysosomal enzymes. Even at 1 h, little radioactivity was found in the fractions containing a cell surface enzyme. This suggests that in each tissue, the 111In-DTPA-octreotide was rapidly shuttled from the cell surface to lysosomes. In the liver, hepatocyte lysosomes were separated from sinusoidal and Kupffer cell lysosomes by administering chloroquine prior to sacrifice. This density shift experiment indicated that 111In-DTPA-octreotide accumulated predominantly in hepatocyte lysosomes. A low molecular weight 111In-DTPA-poly(D)lysine-biotin compound was synthesized, and biodistribution studies showed substantial renal accumulation. The poly(D)lysine backbone conferred resistance to degradation, and this fact allowed determination of the distribution of this compound at the cellular level using an antibiotin antibody and immunohistochemical techniques. These experiments, as well as subcellular fractionation studies, demonstrated that the 111In-DTPA-poly(D)lysine-biotin compound accumulated in the lysosomes of proximal renal tubular cells. These results indicate that lysosomes play a critical role in the cellular physiology of radiolabeled polypeptides. Using these data, we propose a comprehensive model that summarizes the factors that govern the target to background ratios of radiolabeled polypeptides.
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Affiliation(s)
- J R Duncan
- The Mallinckrodt Institute of Radiology and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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30
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Abstract
RATIONALE AND OBJECTIVES Diagnostic radiology chief residents were surveyed on issues related to residency training to compare features and gauge trends in training. METHODS Questionnaires were mailed to accredited programs in the United States. A variety of demographic and common-interest questions were asked. RESULTS Forty-three percent of surveys were returned. The percentage of female residents was similar to that reported in other recent surveys; however, the percentage of women among 1st-year residents had decreased. Resident salaries had increased, although the average salary for a 4th-year resident had decreased when adjusted for inflation. Most 1st-year residents started participating in overnight hospital coverage by their 12th month of residency, and the total number of call days during residency correlated inversely with the size of the residency program. Almost half of residency programs used a night-float resident to provide after-hours coverage. CONCLUSION The information derived from the survey should be useful for program evaluation and future planning.
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Affiliation(s)
- F K VanWagenen
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
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31
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Ottino P, Duncan JR. Effect of vitamin E and indomethacin treatment on adenylate cyclase activity, PGE2 and cAMP levels in murine melanoma cells. Prostaglandins Leukot Essent Fatty Acids 1997; 56:143-9. [PMID: 9051724 DOI: 10.1016/s0952-3278(97)90511-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Malignant murine melanoma (BL6) cells cultured in vitro were supplemented with indomethacin (0.15 microM) and varying levels (1-10 micrograms/ml) of vitamin E succinate. The effect of combined indomethacin and vitamin E succinate treatment on the growth as well as the levels of adenylate cyclase activity, prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP) were determined in these cells. BL6 cells supplemented with 0.15 microM indomethacin and 1-10 micrograms/ml vitamin E succinate showed a significant (P < or = 0.05) decrease in growth at 1 microgram/ml vitamin E succinate, while at 3-10 micrograms/ml, no significant increase or decrease in growth was observed when compared to control cultures (OE). Results from studies of adenylate cyclase activity in BL6 cells showed no significant increase or decrease in enzyme activity, nor were the levels of PGE2 and cAMP affected when the cells were supplemented with 0.15 microM indomethacin and 1-10 micrograms/ml vitamin E succinate.
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Affiliation(s)
- P Ottino
- Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
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Stoll A, Duncan JR. Implementation of a continuous-flow stirred bioreactor system in the bioremediation of heavy metals from industrial waste water. Environ Pollut 1997; 97:247-251. [PMID: 15093362 DOI: 10.1016/s0269-7491(97)00094-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/1996] [Accepted: 06/19/1997] [Indexed: 05/24/2023]
Abstract
The industrial applicability of immobilized non-viable yeast biomass (Saccharomyces cerivisiae) in continuous-flow stirred bioreactors was tested with respect to metal removal from electroplating effluent solutions containing Cu, Cd, Cr, Ni and Zn in excess of the stipulated water quality criteria. Two systems, a dual bioreactor and triple bioreactor system in series, were tested and compared regarding their efficiency of metal removal. The system containing two bioreactors linked in series provided a more efficient solution to the problem. The introduction of a third bioreactor into the system had a marginal effect on the amount of metal removed. Subsequent to treatment within the bioreactors the levels of Cu, Cr and Ni in the effluent complied with the stipulated drinking water quality criteria and, although in excess of these criteria only 18% of the initial Zn and 17% of the Cd remained in solution.
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Affiliation(s)
- A Stoll
- Department of Biochemistry and Microbiology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa
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33
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Abstract
Numerous studies have proposed a radical or oxidant involvement in a number of degenerative diseases such as cancer. This has led to suggestions that the supplementation of antioxidants such as alpha-tocopherol (vitamin E) may function to reduce the growth of cancer. In this study, a nonmalignant Monkey kidney (LLCMK) and a malignant Murine melanoma (BL6-F10) cell line were supplemented with varying levels of alpha-Tocopherol acid succinate (vitamin E succinate) ranging from 1 to 10 microg/ml. BL6-F10 cells supplemented with 5, 7, and 10 microg/ml vitamin E succinate, showed significant decreases in cell proliferation, and this decrease was accompanied by a concomitant increase rather than a decrease in the levels of free radicals and lipid peroxidation. LLCMK cells supplemented with 1-10 microg/ml vitamin E succinate showed no significant increase or decrease in growth, while the levels of lipid peroxidation were shown to be insignificantly elevated at 5, 7, and 10 microg/ml vitamin E succinate. Free radical levels in LLCMK cells were significantly decreased at 1 microg/ml vitamin E succinate, while at 3, 5, 7, and 10 microg/ml supplementary vitamin E succinate, free radical levels increased compared to the 1 microg/ml group, but not compared to control cultures. These results suggest that the inhibitory effects of vitamin E succinate on BL6-F10 cell growth in vitro is not a consequence of its antioxidant properties, but may, in fact, be due to one or more of its other potential roles within the cells, such as the regulation of cellular enzyme activities involved in growth.
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Affiliation(s)
- P Ottino
- Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
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Bowling WM, Kennedy SC, Cai SR, Duncan JR, Gao C, Flye MW, Ponder KP. Portal branch occlusion safely facilitates in vivo retroviral vector transduction of rat liver. Hum Gene Ther 1996; 7:2113-21. [PMID: 8934225 DOI: 10.1089/hum.1996.7.17-2113] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Hepatic gene therapy might correct the clinical manifestations of several genetic disorders in patients. Although retroviral vectors with a strong liver-specific promoter can result in stable and therapeutic levels of expression of genes from the liver, application of these techniques in humans is limited by the need to perform one or more invasive procedures to achieve ex vivo or in vivo transduction of hepatocytes. In vivo delivery involves injection of retrovirus into the portal vein during liver regeneration. Although transduction is efficient and specific for the liver, induction of hepatocyte replication requires a 70% partial hepatectomy or administration of a liver toxin. An alternative method for inducing hepatocyte replication is to occlude branches of the portal vein. This results in apoptosis of hepatocytes in the occluded lobes and compensatory replication of the hepatocytes in the nonoccluded lobes. We demonstrate here that portal branch occlusion is nearly as effective as partial hepatectomy at facilitating retroviral vector transduction in vivo and has a lower morbidity. Portal branch occlusion could be performed in larger animals by minimally invasive techniques and has been used safely to treat human patients with liver cancer. Portal branch occlusion might ultimately be used in humans to facilitate retroviral vector transduction in vivo for the treatment of genetic diseases.
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Affiliation(s)
- W M Bowling
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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35
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Stoll A, Duncan JR. Enhanced heavy metal removal from waste water by viable, glucose pretreated Saccharomyces cerevisiae cells. Biotechnol Lett 1996. [DOI: 10.1007/bf00128594] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Previous studies have shown that vitamin E supplementation inhibits murine melanoma cell growth in vitro. In this study, malignant murine melanoma (BL6) and non-malignant monkey kidney (LLCMK) cells were supplemented with 1-10 micrograms/ml D-alpha-tocopherol acid succinate (vitamin E succinate). The effect of vitamin E succinate supplementation on growth as well as the levels of adenylate cyclase activity, prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP) were determined in these cells. Results from these studies indicated a significant inhibition of BL6 cell growth at 5 (P < 0.025), 7 and 10 micrograms/ml (P < 0.001) vitamin E succinate supplementation, while LLCMK cells showed no significant increase or decrease in growth following vitamin E succinate supplementation. BL6 cells supplemented with 7 and 10 micrograms/ml vitamin E succinate showed a marked increase in PGE2 levels, with a significant increase (P < 0.025) occurring at 10 micrograms/ml. Adenylate cyclase activity in BL6 cells was also significantly increased at vitamin E succinate concentrations of 7 (P < 0.05) and 10 micrograms/ml (P < 0.05), respectively, and supplementation of these cells with 5 (P < 0.05), 7 and 10 micrograms/ml (P < 0.001) vitamin E succinate resulted in a significant increase in the levels of cAMP, while LLCMK cells showed no significant increase or decrease in PGE2, adenylate cyclase activity or cAMP levels over the vitamin concentrations tested.
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Affiliation(s)
- P Ottino
- Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
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Affiliation(s)
- N D Sargison
- Woodside Veterinary Clinic, Torphins, Aberdeenshire
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38
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Abstract
RATIONALE AND OBJECTIVES Radiology chief residents are surveyed annually and the data are used to improve the training of diagnostic radiology residents. METHODS Questionnaires were mailed to accredited programs in the United States and Canada. A variety of demographic and common-interest questions were asked. For the first time, an individual resident questionnaire also was included. RESULTS Completed surveys from 53 programs (42%) were returned. The percentage of female residents was similar to that reported in other recent surveys. Resident salaries continued to increase. Residency selection remained highly competitive. Residents indicated that the utility of a fellowship in radiology exceeded the utility of clinical training in other fields prior to the radiology residency. Residents agreed with recommendations by the American Association of Academic Chief Residents in Radiology concerning proposed changes in the American Board of Radiology (ABR) examinations. CONCLUSION The information derived from the surveys on resident selection, the utility of preradiology clinical training, and the ABR examination may be useful for residents, program directors, and departmental chairs.
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Affiliation(s)
- J R Duncan
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Rogers BE, Franano FN, Duncan JR, Edwards WB, Anderson CJ, Connett JM, Welch MJ. Identification of metabolites of 111In-diethylenetriaminepentaacetic acid-monoclonal antibodies and antibody fragments in vivo. Cancer Res 1995; 55:5714s-5720s. [PMID: 7493333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The in vivo fate of various 111In-labeled polypeptides has been the subject of many investigations. Intracellular metabolism has been studied through the use of 111In-labeled glycoproteins that are concentrated in the lysosome by receptor-mediated endocytosis. These studies have indicated that the main lysosomal metabolite is 111In-chelate-epsilon-lysine, both in vitro and in vivo (Y. Arano et al., J. Nucl. Med., 35: 890-898, 1994; F. N. Franano et al., Nucl. Med. Biol., 21: 1023-1034, 1994). Since the vast majority of radiolabeled antibodies do not localize within the target tissue, an understanding of the metabolism of 111In-labeled antibodies in nontarget tissues is important for the rational design of future radiolabeled antibodies. We investigated the in vivo metabolism of 111In-DTPA3-conjugated antibody in female Sprague-Dawley rats using the anticolorectal carcinoma monoclonal antibody (MAb) 1A3 and MAb 1A3-F(ab')2. Livers and kidneys were harvested from rats injected with either intact MAb or MAb fragments and analyzed by gel filtration chromatography. Thirty-five % of the radioactivity from 111In-DTPA-1A3 MAb present in the liver was in the form of a low molecular weight species at 1 through 5 days. In contrast, 111In-DTPA-1A3-F(ab')2 was > 98% degraded to a low molecular weight species in the kidney after 1 day. In each case, the low molecular weight metabolites were collected and further analyzed by silica gel thin-layer chromatography, reversed phase high-performance liquid chromatography, and ion-exchange chromatography and compared to 111In-DTPA and 111In-DTPA-epsilon-lysine standards. In each system, the major metabolite co-eluted with 111In-DTPA-epsilon-lysine, similar to the results obtained with 111In-labeled glycoproteins that are delivered to lysosomes by receptor-mediated endocytosis. A minor metabolite that was more highly charged than 111In-DTPA was also observed. Analysis of urine and feces demonstrated that the main excretory product of both 111In-labeled intact 1A3 and 1A3-F(ab')2 was 111In-DTPA-epsilon-lysine. Based on this data, we propose that 111In-DTPA-antibodies are degraded within lysosomes of nontarget organs such as the liver and kidneys.
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Affiliation(s)
- B E Rogers
- Mallinckrodt Institute of Radiology, Washington University, School of Medicine, St. Louis, Missouri 63110, USA
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41
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Abstract
To test the hypothesis that the developmental toxicity of cadmium (Cd) is due in part to oxidative damage, embryos were cultured in medium containing 0.0, 1.0, 3.0, or 6.0 microM Cd with or without various antioxidants for 72 h. Ascorbate, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and glutathione (GSH) were all effective at ameliorating 1.0 microM Cd-induced embryotoxicity. For embryos cultured in medium containing either 3.0 or 6.0 microM Cd, GSH was effective at ameliorating Cd toxicity while the other antioxidants tested were ineffective. Pretreating embryos with antioxidants for 24 h prior to exposing them to Cd and antioxidants did not significantly alter the previously observed improvement with the exception that pretreatment with GSH virtually eliminated Cd-induced embryotoxicity between 1.0 and 6.0 microM Cd. A 4-h exposure to GSH prior to culture in Cd markedly improved embryo development suggesting that GSH taken up during pretreatment can provide protection against Cd-induced embryotoxicity. This work supports the hypothesis that the developmental toxicity of Cd is in part due to oxidative damage that can be modulated by select antioxidants.
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Affiliation(s)
- J M Peters
- Department of Obstetrics and Gynecology, University of California, Davis 95616, USA
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42
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Abstract
Non-malignant LLCMK cells and malignant B16 cells were supplemented with ascorbate, over the concentration range 0-100 micrograms/ml ascorbate. The effects of ascorbate supplementation on cell growth and phospholipase A2 activity of the membrane fractions of the respective cell lines were determined. Increasing ascorbate supplementation had a significant inhibitory effect on the growth of the B16 cells. Phospholipase A2 activity in the control B16 cells was lower than that detected in the control LLCMK cells. Phospholipase A2 activity decreased significantly in the B16 cells upon increasing ascorbate supplementation, while the supplementation of ascorbate to the LLCMK cells did not have any significant effect on phospholipase A2 activity in these cells.
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Affiliation(s)
- K E Stoll
- Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
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Abstract
The effect of a metallothionein (MT) antisense oligodeoxynucleotide (ODN) on mouse preimplantation embryo development was investigated. Preimplantation embryos were cultured for 72 h and examined following exposure to either an MT antisense or sense ODN. Blastocyst formation (cavitation) and embryo cell number were lower in embryos exposed to the MT antisense ODN than in controls or in embryos exposed to the MT sense ODN. In embryos cultured in medium containing free nucleotides, cavitation frequency was not affected, although mean embryo cell number was lower than in controls. Combined, this work shows that an antisense ODN against MT can significantly affect blastocyst formation of preimplantation embryos; some, but not all, of the observed effects on embryo cell number may have been due to nucleotide toxicity.
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Affiliation(s)
- J M Peters
- Department of Obstetrics and Gynecology, University of California, Davis 95616, USA
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Duncan JR, McGregor JR, O'Dwyer PJ. Death from malignant disease after surgery for duodenal ulcer. Gut 1995; 36:475. [PMID: 7698714 PMCID: PMC1382470 DOI: 10.1136/gut.36.3.475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Franano FN, Edwards WB, Welch MJ, Brechbiel MW, Gansow OA, Duncan JR. Biodistribution and metabolism of targeted and nontargeted protein-chelate-gadolinium complexes: evidence for gadolinium dissociation in vitro and in vivo. Magn Reson Imaging 1995; 13:201-14. [PMID: 7739361 DOI: 10.1016/0730-725x(94)00100-h] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The intracellular metabolism of receptor-targeted 153Gd-DTPA-glycoproteins was studied in vitro and in vivo. These agents bound to cell surface receptors, underwent receptor mediated endocytosis, and were rapidly degraded to a metabolite which co-migrated with a 153Gd-DTPA-lysine standard on thin layer chromatography. The rates of dissociation of 153Gd and 111In from a glycoprotein-chelate conjugate were determined in vitro. Gadolinium readily dissociated, in a pH-sensitive manner, from glycoprotein-DTPA, and to a lesser degree glycoprotein-MX-DTPA. The biodistribution of targeted and blood pool 153Gd/111In labeled proteins also suggested that gadolinium dissociates from protein-DTPA and protein-MX-DTPA and their metabolites leading to an accumulation of gadolinium in bone. Metal-DTPA-glycoprotein agents targeted to cell surface receptors can still produce very high concentrations of radioactive or paramagnetic metals within the lysosome due to the high rate of accumulation afforded by receptor mediated endocytosis and the low release rate of metabolites such as metal-DTPA-lysine. However, the continued development of gadolinium based macromolecular agents will require improvements in bifunctional chelates.
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Affiliation(s)
- F N Franano
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Brady D, Rose PD, Duncan JR. The use of hollow fiber cross-flow microfiltration in bioaccumulation and continuous removal of heavy metals from solution by Saccharomyces cerevisiae. Biotechnol Bioeng 1994; 44:1362-6. [DOI: 10.1002/bit.260441113] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Franano FN, Edwards WB, Welch MJ, Duncan JR. Metabolism of receptor targeted 111In-DTPA-glycoproteins: identification of 111In-DTPA-epsilon-lysine as the primary metabolic and excretory product. Nucl Med Biol 1994; 21:1023-34. [PMID: 9234360 DOI: 10.1016/0969-8051(94)90174-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The hepatic and renal retention of indium-111 (111In) from 111In-labeled polypeptides has been the subject of many investigations. Because the lysosome is a common intracellular destination for the degradation of polypeptides, we studied the lysosomal metabolism of 111In-DTPA-labeled glycoproteins targeted to cell surface receptors in vitro and in vivo. We found that 111In-DTPA-glycoproteins were degraded to 111In-DTPA-epsilon-lysine, which was slowly released from cells and recovered intact in urine and feces. These results suggest a mechanism for 111In retention at target and non-target sites.
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Affiliation(s)
- F N Franano
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
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Brady D, Stoll AD, Starke L, Duncan JR. Chemical and enzymatic extraction of heavy metal binding polymers from isolated cell walls ofSaccharomyces cerevisiae. Biotechnol Bioeng 1994; 44:297-302. [DOI: 10.1002/bit.260440307] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Affiliation(s)
- J R Duncan
- Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110
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Abstract
Previous studies have shown that ascorbate (Asc) supplementation affects arachidonic acid (AA) and prostaglandin E2 (PGE2) levels in B16 murine melanoma cells. In this study, non-malignant LLCMK cells and malignant B16 cells were respectively supplemented with 20 microCi 15-3H AA, to investigate whether these two cell types were able to take up AA from the media. Furthermore, these cells were also supplemented with Asc (0-100 micrograms/ml) to determine the effect of Asc supplementation on 15-3H AA uptake. Both cell types incorporated 15-3H AA, while Asc supplementation enhanced this 15-3H AA uptake. To determine the site of the AA incorporation, both cell types were supplemented with 2.5 microM AA and Asc (0-100 micrograms/ml). The % AA composition of the stroma fractions of both cell types was increased with 100 micrograms/ml Asc supplementation. Supplementation of these cells with AA (0-50 microM) resulted in an increase in PGE2 levels in the B16 cells. Since PGE2 has been shown, in turn, to stimulate adenylate cyclase (AC) activity, the LLCMK and B16 cells were supplemented with 0-100 microM PGE2. A 3-fold increase of AC activity in the B16 cells occurred as a result of this supplementation.
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Affiliation(s)
- K E Stoll
- Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
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