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Sewell F, Ragan I, Horgan G, Andrew D, Holmes T, Manou I, Müller BP, Rowan T, Schmitt BG, Corvaro M. New supporting data to guide the use of evident toxicity in acute oral toxicity studies (OECD TG 420). Regul Toxicol Pharmacol 2024; 146:105517. [PMID: 37838350 DOI: 10.1016/j.yrtph.2023.105517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 10/03/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
Currently there are three test guidelines (TG) for acute oral toxicity studies of substances or mixtures from the Organisation for Economic Co-operation and Development (OECD). TG 423 and TG 425 use lethality as an endpoint, while TG 420 replaces death with 'evident toxicity', defined as clear signs that exposure to a higher dose would result in death. However, the perceived subjectivity of 'evident toxicity' may be preventing wider use of TG 420. To address this, the UK National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) and the European Partnership for Alternative Approaches to Animal Testing (EPAA) collaborated to provide recommendations on the recognition of 'evident toxicity'. Historical data from acute oral toxicity studies were analysed for clinical signs at the lower dose that could have predicted death at the higher dose. Several signs including ataxia, laboured respiration, and eyes partially closed, alone or in combination, are highly predictive. Others such as lethargy, decreased respiration, and loose faeces have lower but still appreciable positive predictive value (PPV). The data has been used to develop recommendations to promote use of TG 420 and thus reduce the suffering and numbers of animals used in acute oral toxicity studies.
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Affiliation(s)
- Fiona Sewell
- UK National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK.
| | - Ian Ragan
- UK National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
| | - Graham Horgan
- Biomathematics and Statistics Scotland (BioSS), Aberdeen, UK
| | | | | | - Irene Manou
- European Partnership for Alternative Approaches to Animal Testing (EPAA), Brussels, Belgium
| | | | - Tim Rowan
- European Partnership for Alternative Approaches to Animal Testing (EPAA), Brussels, Belgium
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2
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Holmes T, Andrew D, Corvaro M, Manou I, Mueller B, Rowan T, Horgan G, Sewell F. P21-18 New data supporting recognition of evident toxicity in acute oral toxicity studies (OECD TG 420). Toxicol Lett 2022. [DOI: 10.1016/j.toxlet.2022.07.698] [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: 11/26/2022]
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3
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Smith A, Wall RJ, Patterson S, Rowan T, Rico Vidal E, Stojanovski L, Huggett M, Hampton SE, Thomas MG, Corpas Lopez V, Gillingwater K, Duke J, Napier G, Peter R, Vitouley HS, Harrison JR, Milne R, Jeacock L, Baker N, Davis SH, Simeons F, Riley J, Horn D, Brun R, Zuccotto F, Witty MJ, Wyllie S, Read KD, Gilbert IH. Repositioning of a Diaminothiazole Series Confirmed to Target the Cyclin-Dependent Kinase CRK12 for Use in the Treatment of African Animal Trypanosomiasis. J Med Chem 2022; 65:5606-5624. [PMID: 35303411 PMCID: PMC9014415 DOI: 10.1021/acs.jmedchem.1c02104] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Indexed: 11/29/2022]
Abstract
African animal trypanosomiasis or nagana, caused principally by infection of the protozoan parasites Trypanosoma congolense and Trypanosoma vivax, is a major problem in cattle and other livestocks in sub-Saharan Africa. Current treatments are threatened by the emergence of drug resistance and there is an urgent need for new, effective drugs. Here, we report the repositioning of a compound series initially developed for the treatment of human African trypanosomiasis. A medicinal chemistry program, focused on deriving more soluble analogues, led to development of a lead compound capable of curing cattle infected with both T. congolense and T. vivax via intravenous dosing. Further optimization has the potential to yield a single-dose intramuscular treatment for this disease. Comprehensive mode of action studies revealed that the molecular target of this promising compound and related analogues is the cyclin-dependent kinase CRK12.
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Affiliation(s)
- Alasdair Smith
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Richard J. Wall
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Stephen Patterson
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Tim Rowan
- GALVmed, Doherty Building, Pentlands Science
Park, Bush Loan, Penicuik, Edinburgh EH26 0PZ, United Kingdom
| | - Eva Rico Vidal
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Laste Stojanovski
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Margaret Huggett
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Shahienaz E. Hampton
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Michael G. Thomas
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Victoriano Corpas Lopez
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Kirsten Gillingwater
- Swiss
Tropical and Public Health Institute, Socinstrasse 57, CH-4002 Basel, Switzerland
- University
of Basel, Petersplatz 1, CH-4001 Basel, Switzerland
| | - Jeff Duke
- University
of Greenwich, Medway Campus, Central Avenue, Chatham Maritime, Chatham, Kent ME4 4TB United Kingdom
| | - Grant Napier
- GALVmed, Doherty Building, Pentlands Science
Park, Bush Loan, Penicuik, Edinburgh EH26 0PZ, United Kingdom
| | - Rose Peter
- GALVmed, Doherty Building, Pentlands Science
Park, Bush Loan, Penicuik, Edinburgh EH26 0PZ, United Kingdom
| | - Hervé S. Vitouley
- Centre
International de Recherche-Développement sur l’Elevage
en zone Subhumide (CIRDES), No 559 ru
5-31 angle Av. du Gouverneur Louveau, 01 BP: 454 Bobo-Dioulasso 01, Burkina Faso
| | - Justin R. Harrison
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Rachel Milne
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Laura Jeacock
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Nicola Baker
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Susan H. Davis
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Frederick Simeons
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Jennifer Riley
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - David Horn
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Reto Brun
- Swiss
Tropical and Public Health Institute, Socinstrasse 57, CH-4002 Basel, Switzerland
- University
of Basel, Petersplatz 1, CH-4001 Basel, Switzerland
| | - Fabio Zuccotto
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Michael J Witty
- GALVmed, Doherty Building, Pentlands Science
Park, Bush Loan, Penicuik, Edinburgh EH26 0PZ, United Kingdom
| | - Susan Wyllie
- Wellcome
Centre for Anti-Infectives Research, Division of Biological Chemistry
and Drug Discovery, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Kevin D. Read
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
| | - Ian H. Gilbert
- Drug
Discovery Unit, Wellcome Centre for Anti-Infectives Research, Division
of Biological Chemistry and Drug Discovery, University of Dundee, Dow Street, Dundee DD1
5EH, United Kingdom
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Steketee PC, Dickie EA, Iremonger J, Crouch K, Paxton E, Jayaraman S, Alfituri OA, Awuah-Mensah G, Ritchie R, Schnaufer A, Rowan T, de Koning HP, Gadelha C, Wickstead B, Barrett MP, Morrison LJ. Divergent metabolism between Trypanosoma congolense and Trypanosoma brucei results in differential sensitivity to metabolic inhibition. PLoS Pathog 2021; 17:e1009734. [PMID: 34310651 PMCID: PMC8384185 DOI: 10.1371/journal.ppat.1009734] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 08/24/2021] [Accepted: 06/21/2021] [Indexed: 11/18/2022] Open
Abstract
Animal African Trypanosomiasis (AAT) is a debilitating livestock disease prevalent across sub-Saharan Africa, a main cause of which is the protozoan parasite Trypanosoma congolense. In comparison to the well-studied T. brucei, there is a major paucity of knowledge regarding the biology of T. congolense. Here, we use a combination of omics technologies and novel genetic tools to characterise core metabolism in T. congolense mammalian-infective bloodstream-form parasites, and test whether metabolic differences compared to T. brucei impact upon sensitivity to metabolic inhibition. Like the bloodstream stage of T. brucei, glycolysis plays a major part in T. congolense energy metabolism. However, the rate of glucose uptake is significantly lower in bloodstream stage T. congolense, with cells remaining viable when cultured in concentrations as low as 2 mM. Instead of pyruvate, the primary glycolytic endpoints are succinate, malate and acetate. Transcriptomics analysis showed higher levels of transcripts associated with the mitochondrial pyruvate dehydrogenase complex, acetate generation, and the glycosomal succinate shunt in T. congolense, compared to T. brucei. Stable-isotope labelling of glucose enabled the comparison of carbon usage between T. brucei and T. congolense, highlighting differences in nucleotide and saturated fatty acid metabolism. To validate the metabolic similarities and differences, both species were treated with metabolic inhibitors, confirming that electron transport chain activity is not essential in T. congolense. However, the parasite exhibits increased sensitivity to inhibition of mitochondrial pyruvate import, compared to T. brucei. Strikingly, T. congolense exhibited significant resistance to inhibitors of fatty acid synthesis, including a 780-fold higher EC50 for the lipase and fatty acid synthase inhibitor Orlistat, compared to T. brucei. These data highlight that bloodstream form T. congolense diverges from T. brucei in key areas of metabolism, with several features that are intermediate between bloodstream- and insect-stage T. brucei. These results have implications for drug development, mechanisms of drug resistance and host-pathogen interactions.
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Affiliation(s)
- Pieter C Steketee
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Emily A Dickie
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - James Iremonger
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Kathryn Crouch
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Edith Paxton
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Siddharth Jayaraman
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Omar A Alfituri
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Ryan Ritchie
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Achim Schnaufer
- Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Tim Rowan
- Global Alliance for Livestock Veterinary Medicines, Edinburgh, United Kingdom
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Catarina Gadelha
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Bill Wickstead
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Michael P Barrett
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom.,Glasgow Polyomics, University of Glasgow, Glasgow, United Kingdom
| | - Liam J Morrison
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
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5
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O'Shea C, Murphy CH, Loane D, Diettrich C, McTiernan E, Hyland E, Campbell M, Kinnarney G, Rowan T, Ferns M, Phelan P, Lee P, Bryant M, Glennon C. 10Weight Trends among Residents in HSE Residential Care Sites for Older Persons in CHO 8 (Midlands Area) – an Exploratory Study. Age Ageing 2018. [DOI: 10.1093/ageing/afy140.03] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- C O'Shea
- University College Dublin, Dublin, Ireland
| | - C H Murphy
- University College Dublin, Dublin, Ireland
| | - D Loane
- Community Nutrition & Dietetic Service, HSE CHO 8 (Midlands Area), Primary Care Centre, Mountmellick, Co. Laois, Ireland
| | - C Diettrich
- Community Nutrition & Dietetic Service, HSE CHO 8 (Midlands Area), St. Fintans Hospital, Portlaoise, Co. Laois, Ireland
| | - E McTiernan
- St. Joseph’s Care Centre, Dublin Road, Longford, Ireland
| | - E Hyland
- St. Joseph’s Care Centre, Dublin Road, Longford, Ireland
| | - M Campbell
- Cluain Lir Care Centre, Mullingar, Co. Westmeath, Ireland
| | - G Kinnarney
- Riada House Care Centre, Tullamore, Co. Offaly, Ireland
| | - T Rowan
- Ofalia House Care Centre, Edenderry, Co. Offaly, Ireland
| | - M Ferns
- St. Brigid’s Care Centre, Shaen, Co. Laois, Ireland
| | - P Phelan
- St. Vincent’s Care Centre, Mountmellick, Co. Laois, Ireland
| | - P Lee
- St. Vincent’s Care Centre, Athlone, Co. Westmeath, Ireland
| | - M Bryant
- Community Nursing Unit, Birr, Co. Offaly, Ireland
| | - C Glennon
- Community Nutrition & Dietetic Service, HSE CHO 8 (Midlands Area), Primary Care Unit, St. Loman’s Hospital, Mullingar, Co. Westmeath, Ireland
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6
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Grandemange E, Perrin PA, Cvejic D, Haas M, Rowan T, Hellmann K. Randomised controlled field study to evaluate the efficacy and clinical safety of a single 8 mg/kg injectable dose of marbofloxacin compared with one or two doses of 7.5 mg/kg injectable enrofloxacin for the treatment of Actinobacillus pleuropneumoniae infections in growing-fattening pigs in Europe. Porcine Health Manag 2017; 3:10. [PMID: 28496988 PMCID: PMC5424389 DOI: 10.1186/s40813-017-0057-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 04/04/2017] [Indexed: 11/23/2022] Open
Abstract
Background Acute outbreaks of Actinobacillus pleuropneumoniae (APP) require rapid, effective, parenteral antimicrobial treatment. The efficacy and safety of a single, short-acting, high dose of marbofloxacin (Forcyl® swine 160 mg/mL) compared with 1 or 2 doses of 7.5 mg/kg enrofloxacin in APP outbreaks in European farms was studied. Methods A controlled, randomised block, blinded, multicentre, field study was conducted on four farms with acute respiratory disease associated with APP. Animals with clinical signs of respiratory disease were allocated similarly to intramuscular treatments of either a single dose 8 mg/kg marbofloxacin on day 0 or, 7.5 mg/kg enrofloxacin (Baytril 1nject®) on day 0 and again on day 2, if clinical signs had not improved. Results The results were similar for intention to treat (242 pigs) and per protocol populations (239 pigs). On day 0, all pigs had pyrexia (means, 40.6 °C), moderate to severe clinical signs (depression, cough, dyspnoea). Following treatment, animals improved rapidly and on day 7, clinical signs were absent or mild in all pigs and mean temperatures for each treatment were <39.5 °C (P > 0.05). The primary efficacy criterion, animals cured, for marbofloxacin and enrofloxacin was 81.8 and 81.4% on day 7, and 84.2 and 82.2% on day 21, respectively. Results for cure, respiratory disease removals and mortalities, and relapses were compared using confidence intervals and confirmed that marbofloxacin was non-inferior to enrofloxacin (P > 0.05). There were no significant treatment differences in live weight gains, adverse events and injection site reactions (<2.5% animals) (P > 0.05). Significantly more animals developed concurrent disorders in the enrofloxacin (7.5%) than marbofloxacin (0.0%) group (P < 0.01). On day 0, the MIC90 values of APP for marbofloxacin and enrofloxacin were 0.06 μg/mL for APP, less than the clinical breakpoints. Conclusions Marbofloxacin (single dose of 8 mg/kg) and enrofloxacin (1 or 2 doses of 7.5 mg/kg) were clinically safe and effective in the treatment of clinical respiratory disease associated predominantly with APP in four European commercial, fattening pig herds.
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Affiliation(s)
- Erik Grandemange
- Vetoquinol SA, Research and Development Centre, B.P. 189, 70204 Lure Cedex, France
| | | | - Dejean Cvejic
- Klifovet AG, Geyerspergerstr 27, D-80689 Munich, Germany
| | - Miriam Haas
- Klifovet AG, Geyerspergerstr 27, D-80689 Munich, Germany
| | - Tim Rowan
- Rowdix Ltd, Folly Hall, Cawton, York, YO62 4LW UK
| | - Klaus Hellmann
- Klifovet AG, Geyerspergerstr 27, D-80689 Munich, Germany
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7
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Dagnachew S, Tsegaye B, Awukew A, Tilahun M, Ashenafi H, Rowan T, Abebe G, Barry DJ, Terefe G, Goddeeris BM. Prevalence of bovine trypanosomosis and assessment of trypanocidal drug resistance in tsetse infested and non-tsetse infested areas of Northwest Ethiopia. Parasite Epidemiol Control 2017; 2:40-49. [PMID: 29774280 PMCID: PMC5952666 DOI: 10.1016/j.parepi.2017.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 02/16/2017] [Accepted: 02/18/2017] [Indexed: 11/28/2022] Open
Abstract
The Northwestern region of Ethiopia is affected by both tsetse and non-tsetse transmitted trypanosomosis with a significant impact on livestock productivity. The control of trypanosomosis in Ethiopia relies on either curative or prophylactic treatment of animals with diminazene aceturate (DA) or isometamidium chloride (ISM). In the present work; questionnaire survey, cross-sectional and experimental studies were carried out to; a) assess the utilization of trypanocidal drugs; b) determine the prevalence of bovine trypanosomosis and; c) assess the drug resistant problems respectively in Tsetse and non-tsetse infested areas on NW Ethiopia. A total of 100 respondents were included for the survey and the questionnaires focused on the drug utilization practices for the control of Trypanosomosis. Blood from cattle 640 (324 cattle tested in 2011, 316 cattle tested in 2012) and 795 (390 cattle tested in 2011, 405 cattle tested in 2012) were examined from tsetse infested and non-tsetse infested areas respectively using the buffy coat technique and thin blood smear for the detection of trypanosomes and measurement of packed cell volume (PCV). For the assessment of trypanocidal drug resistance three isolates, one from tsetse (TT) and two from non-tsetse (NT) areas were used on thirty six trypanosome naïve calves. The experimental animals were divided randomly into six groups of six animals (TT-ETBS2-DA, TT-ETBS2-ISM, NT-ETBD2-DA, NT-ETBD2-ISM, NT-ETBD3-DA and NT-ETBD3-ISM), which were infected with T. vivax isolated from a tsetse-infested or non-tsetse infested area with 2 × 106 trypanosomes from donor animals, and in each case treated with higher dose of DA or ISM. The results of the questionnaire survey showed trypanosomosis was a significant animal health constraint for 84% and 100% of the farmers questioned in non-tsetse and tsetse infested areas of Northwest Ethiopia respectively. Responses on trypanocidal drug utilization practices indicated that risk factors for the development of drug resistance are common and treatment failures are frequently seen. Accordingly, the majority of farmers in tsetse infested area get trypanocides from drug stores and unauthorized sources whereas those from non-tsetse area get from veterinary clinics. Moreover, treatment administration is mainly by animal health personnel and treatment frequency is a maximum of three times/year/animal in non-tsetse area whereas it is administered mainly by the farmers more than seven times/year/animal in tsetse infested area. The prevalence of trypanosomosis varied from 17.59% in 2011 to 25.0% in 2012 in tsetse infested areas with a significant (P = 0.023) difference. Similarly, in non-tsetse infested area the prevalence was varied from 3.85% in 2011 to 5.93% in 2012 without significant rise. Trypanosoma congolense (75%) was the most prevalent followed by T. vivax (20.58%) and mixed infections (4.41%) in tsetse infested area while in non-tsetse infested area only T. vivax was detected. The overall mean PCV in parasitaemic animals (20 ± 2.3 SD) was significantly (P < 0.001) lower than that of aparasitaemic animals (27 ± 4.3 SD). The assessment of trypanocidal drug resistance tests revealed one isolate of non-tsetse infested area against DA in group NT-ETBD2-DA is resistant to the higher dose used with 3 relapsing animals (50% relapses) in the group. Another two relapses were detected one against ISM for the isolate from tsetse infested area (TT-ETBS2-ISM) and one against DA for another isolate (NT-ETBD3-DA) from the non-tsetse area. In conclusion, trypanosomosis is widely prevalent in both study areas causing significant reduction in the mean PCV values. Farmers' trypanocidal utilization practices appear to pose risks of drug resistance problems. The in vivo drug resistance tests indicated the presence of resistant parasites with the higher dose against DA for NT-ETBD2 isolate and suspected resistance problems were detected against ISM and DA for TT-ETBS2 and NT-ETBD3 isolates respectively. Therefore, trypanosomosis is a major constraint in Northwest Ethiopia and drug resistance is a threat in the control of trypanosomosis in both study areas.
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Affiliation(s)
| | - Biniam Tsegaye
- Addis Ababa University, CVMA, P. O. Box 34, Debre Zeit, Ethiopia
| | - Addissu Awukew
- Addis Ababa University, CVMA, P. O. Box 34, Debre Zeit, Ethiopia
| | | | - Hagos Ashenafi
- Addis Ababa University, CVMA, P. O. Box 34, Debre Zeit, Ethiopia
| | - Tim Rowan
- Global Alliance for Livestock and Veterinary Medicine, Scotland, UK
| | - Getachew Abebe
- Food and Agriculture Organization of the United Nations, FAO, Addis Ababa, Ethiopia
| | - Dave J Barry
- University of Glasgow, CMVLS, 120 University Place, G12 8TA, Glasgow, UK
| | - Getachew Terefe
- Addis Ababa University, CVMA, P. O. Box 34, Debre Zeit, Ethiopia
| | - Bruno M Goddeeris
- KU Leuven, Faculty of Bioscience Engineering, 30 bus 2456, B-3001 Heverlee, Belgium
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8
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Morrison LJ, Vezza L, Rowan T, Hope JC. Animal African Trypanosomiasis: Time to Increase Focus on Clinically Relevant Parasite and Host Species. Trends Parasitol 2016; 32:599-607. [PMID: 27167665 DOI: 10.1016/j.pt.2016.04.012] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/19/2016] [Accepted: 04/20/2016] [Indexed: 10/21/2022]
Abstract
Animal African trypanosomiasis (AAT), caused by Trypanosoma congolense and Trypanosoma vivax, remains one of the most important livestock diseases in sub-Saharan Africa, particularly affecting cattle. Despite this, our detailed knowledge largely stems from the human pathogen Trypanosoma brucei and mouse experimental models. In the postgenomic era, the genotypic and phenotypic differences between the AAT-relevant species of parasite or host and their model organism counterparts are increasingly apparent. Here, we outline the timeliness and advantages of increasing the research focus on both the clinically relevant parasite and host species, given that improved tools and resources for both have been developed in recent years. We propose that this shift of emphasis will improve our ability to efficiently develop tools to combat AAT.
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Affiliation(s)
- Liam J Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK.
| | - Laura Vezza
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Tim Rowan
- GALVmed, Doherty Building, Pentlands Science Park, Bush Loan, Edinburgh, EH25 0PZ, UK
| | - Jayne C Hope
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
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Tran T, Napier G, Rowan T, Cordel C, Labuschagne M, Delespaux V, Van Reet N, Erasmus H, Joubert A, Büscher P. Development and evaluation of an ITS1 "Touchdown" PCR for assessment of drug efficacy against animal African trypanosomosis. Vet Parasitol 2014; 202:164-70. [PMID: 24685024 DOI: 10.1016/j.vetpar.2014.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/26/2014] [Accepted: 03/01/2014] [Indexed: 10/25/2022]
Abstract
Animal African trypanosomoses (AAT) are caused by flagellated protozoa of the Trypanosoma genus and contribute to considerable losses in animal production in Africa, Latin America and South East Asia. Trypanosoma congolense is considered the economically most important species. Drug resistant T. congolense strains present a threat to the control of AAT and have triggered research into discovery of novel trypanocides. In vivo assessment of trypanocidal efficacy relies on monitoring of treated animals with microscopic parasite detection methods. Since these methods have poor sensitivity, follow-up for up to 100 days after treatment is recommended to increase the chance of detecting recurrent parasitaemia waves. Molecular techniques are more amendable to high throughput processing and are generally more sensitive than microscopic detection, thus bearing the potential of shortening the 100-day follow up period. The study presents a "Touchdown" PCR targeting the internal transcribed spacer 1 of the ribosomal DNA (ITS1 TD PCR) that enables detection and discrimination of different Trypanosoma taxa in a single run due to variations in PCR product sizes. The assay achieves analytical sensitivity of 10 parasites per ml of blood for detection of T. congolense savannah type and T. brucei, and 100 parasites per ml of blood for detection of T. vivax in infected mouse blood. The ITS1 TD PCR was evaluated on cattle experimentally infected with T. congolense during an investigational new veterinary trypanocide drug efficacy study. ITS1 TD PCR demonstrated comparable performance to microscopy in verifying trypanocide treatment success, in which parasite DNA became undetectable in cured animals within two days post-treatment. ITS1 TD PCR detected parasite recrudescence three days earlier than microscopy and had a higher positivity rate than microscopy (84.85% versus 57.58%) in 66 specimens of relapsing animals collected after treatments. Therefore, ITS1 TD PCR provides a useful tool in assessment of drug efficacy against T. congolense infection in cattle. As the assay bears the potential for detection of mixed infections, it may be applicable for drug efficacy studies and diagnostic discrimination of T. vivax and T. congolense against other pathogenic trypanosomes, including T. brucei, T. evansi and T. equiperdum.
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Affiliation(s)
- Thao Tran
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Doherty Building, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, UK; Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Grant Napier
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Doherty Building, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, UK
| | - Tim Rowan
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Doherty Building, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, UK
| | - Claudia Cordel
- ClinVet International (Pty) Ltd., Uitzigweg, Bainsvlei, Bloemfontein, South Africa
| | - Michel Labuschagne
- ClinVet International (Pty) Ltd., Uitzigweg, Bainsvlei, Bloemfontein, South Africa
| | - Vincent Delespaux
- Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Nick Van Reet
- Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Heidi Erasmus
- ClinVet International (Pty) Ltd., Uitzigweg, Bainsvlei, Bloemfontein, South Africa
| | - Annesca Joubert
- ClinVet International (Pty) Ltd., Uitzigweg, Bainsvlei, Bloemfontein, South Africa
| | - Philippe Büscher
- Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
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Bouyer J, Bouyer F, Donadeu M, Rowan T, Napier G. Community- and farmer-based management of animal African trypanosomosis in cattle. Trends Parasitol 2013; 29:519-22. [PMID: 24012356 DOI: 10.1016/j.pt.2013.08.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 08/10/2013] [Accepted: 08/13/2013] [Indexed: 10/26/2022]
Abstract
Tsetse eradication is impossible in many parts of Africa given environmental, political, and economic circumstances. Animal African trypanosomosis (AAT) control then relies on implementation of local, integrated control strategies by communities or farmers that must take into account the eco-epidemiological context and the cattle rearing system to be sustainable.
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Affiliation(s)
- Jérémy Bouyer
- Unité Mixte de Recherche Contrôle des Maladies Animales Exotiques et Emergentes, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, France; Unité Mixte de Recherche 1309 Contrôle des Maladies Animales Exotiques et Emergentes, Institut National de la Recherche Agronomique, Montpellier, France; Institut Sénégalais de Recherches Agricoles, Laboratoire National d'Elevage et de Recherches Vétérinaires, Dakar, BP 2057, Sénégal.
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Munday JC, Rojas López KE, Eze AA, Delespaux V, Van Den Abbeele J, Rowan T, Barrett MP, Morrison LJ, de Koning HP. Functional expression of TcoAT1 reveals it to be a P1-type nucleoside transporter with no capacity for diminazene uptake. Int J Parasitol Drugs Drug Resist 2013; 3:69-76. [PMID: 24533295 PMCID: PMC3862423 DOI: 10.1016/j.ijpddr.2013.01.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 01/19/2013] [Accepted: 01/23/2013] [Indexed: 11/26/2022]
Abstract
It has long been established that the Trypanosoma brucei TbAT1/P2 aminopurine transporter is involved in the uptake of diamidine and arsenical drugs including pentamidine, diminazene aceturate and melarsoprol. Accordingly, it was proposed that the closest Trypanosoma congolense paralogue, TcoAT1, might perform the same function in this parasite, and an apparent correlation between a Single Nucleotide Polymorphism (SNP) in that gene and diminazene tolerance was reported for the strains examined. Here, we report the functional cloning and expression of TcoAT1 and show that in fact it is the syntenic homologue of another T. brucei gene of the same Equilibrative Nucleoside Transporter (ENT) family: TbNT10. The T. congolense genome does not seem to contain a syntenic equivalent to TbAT1. Two TcoAT1 alleles, differentiated by three independent SNPs, were expressed in the T. brucei clone B48, a TbAT1-null strain that further lacks the High Affinity Pentamidine Transporter (HAPT1); TbAT1 was also expressed as a control. The TbAT1 and TcoAT1 transporters were functional and increased sensitivity to cytotoxic nucleoside analogues. However, only TbAT1 increased sensitivity to diamidines and to cymelarsan. Uptake of [3H]-diminazene was detectable only in the B48 cells expressing TbAT1 but not TcoAT1, whereas uptake of [3H]-inosine was increased by both TcoAT1 alleles but not by TbAT1. Uptake of [3H]-adenosine was increased by all three ENT genes. We conclude that TcoAT1 is a P1-type purine nucleoside transporter and the syntenic equivalent to the previously characterised TbNT10; it does not mediate diminazene uptake and is therefore unlikely to play a role in diminazene resistance in T. congolense.
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Affiliation(s)
- Jane C Munday
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom ; Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Karla E Rojas López
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Anthonius A Eze
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Vincent Delespaux
- Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Jan Van Den Abbeele
- Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Tim Rowan
- GALVmed, Pentlands Science Park, Bush Loan, Edinburgh, United Kingdom
| | - Michael P Barrett
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom ; Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Liam J Morrison
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom ; Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom ; Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, United Kingdom
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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Newton HT, Green MJ, Benchaoui H, Cracknell V, Rowan T, Bradley AJ. Comparison of the efficacy of cloxacillin alone and cloxacillin combined with an internal teat sealant for dry-cow therapy. Vet Rec 2008; 162:678-84. [PMID: 18503067 DOI: 10.1136/vr.162.21.678] [Citation(s) in RCA: 22] [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] [Indexed: 11/04/2022]
Abstract
All the quarters in the cows with high somatic cell counts in 10 herds were treated at drying off with either 600 mg cloxacillin or 600 mg cloxacillin and 4 g of an internal teat sealant containing 65 per cent bismuth subnitrate. The quarters were sampled daily for bacteriological tests for the three days before drying off and twice after calving to establish whether they were infected. Clinical mastitis cases were monitored from drying off until 100 days after calving. The odds of a quarter being bacteriologically negative after calving or developing clinical mastitis in the first 100 days after calving were investigated by multilevel logistic regression. The quarters treated with the internal sealant and cloxacillin were significantly more likely to be bacteriologically negative in the immediate period after calving and were significantly less likely to suffer clinical mastitis during the first 100 days after calving than the quarters treated with cloxacillin alone. There was more variation between cows than between herds in the underlying risk of an infection after calving, but there was more variation between herds than between cows in the underlying risk of clinical mastitis during the 100 days after calving.
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Affiliation(s)
- H T Newton
- School of Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU
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Bywater R, Deluyker H, Deroover E, de Jong A, Marion H, McConville M, Rowan T, Shryock T, Shuster D, Thomas V, Vallé M, Walters J. A European survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing animals. J Antimicrob Chemother 2004; 54:744-54. [PMID: 15375107 DOI: 10.1093/jac/dkh422] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.8] [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: 11/13/2022] Open
Abstract
OBJECTIVE To study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology. METHODS Samples were taken at slaughter from chickens, pigs and cattle in four EU countries per host. Escherichia coli (indicator organism; n = 2118), Salmonella spp. (n = 271) and Campylobacter spp. (n = 1325) were isolated in national laboratories and MICs tested in a central laboratory against, where appropriate, ampicillin, cefepime, cefotaxime, ciprofloxacin, chloramphenicol, erythromycin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim/sulfamethoxazole. RESULTS Isolation rates were high for E. coli, low for Salmonella and intermediate for Campylobacter. MIC results showed resistance prevalence varied among compounds, hosts and countries. For E. coli and Salmonella, resistance to newer compounds (cefepime, cefotaxime, ciprofloxacin) was absent or low, but to older compounds (except gentamicin), resistance was variable and higher. E. coli isolates from Sweden showed low resistance, whereas among isolates from Spain (pigs), resistance to ampicillin, chloramphenicol, streptomycin, tetracycline and trimethoprim/sulfamethoxazole was higher; the UK, France, the Netherlands, Germany, Italy and Denmark were intermediate. For Campylobacter spp. isolates from chickens, nalidixic acid and ciprofloxacin resistance was >30% in France and the Netherlands, >6% in the UK and zero in Sweden. Nalidixic acid resistance was high in cattle (20%-64%), whereas ciprofloxacin resistance was markedly lower in cattle, variable in pigs (3%-21%) and highest in Sweden. Generally, Campylobacter coli was more resistant than Campylobacter jejuni. CONCLUSION Antimicrobial resistance among enteric organisms in food animals varied among countries, particularly for older antimicrobials, but resistance to newer compounds used to treat disease in humans was generally low.
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Affiliation(s)
- Robin Bywater
- EASSA Study Group, c/o CEESA, 1, Rue Defacqz, Brussels, Belgium.
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Hübschle O, Godinho K, Rowan T, Nicholas R. Danofloxacin treatment of cattle affected by CBPP. Vet Rec 2004; 155:403. [PMID: 15499816] [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: 05/01/2023]
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16
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Rowan T. Breast cancer: pathologic and prognostic evaluation. Wis Med J 1991; 90:679-84. [PMID: 1843060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Breast cancer presentation is changing, with more tumors detected at an early stage. This makes choosing the most appropriate tests for evaluation of a particular tumor more difficult. Mammography with biopsy of suspicious areas reveals an increasing incidence of microscopic cancers, with a corresponding reduction in larger palpable cancers. Coincidentally, a number of tests for evaluating these cancers, which may affect treatment, have been developed. These includes immunohistochemical evaluation of estrogen receptor and progesterone receptor status and a number of tests still listed as investigational. This paper reviews the diagnosis, evaluation, and prognosis of breast cancers, and suggests an optimal way for handling these tumors.
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Staugaitis SM, Rowan T, Sanes DH, Colman DR, Smith PR. Applications of confocal microscopy to the study of myelin development and neuron structure. J Electron Microsc Tech 1991; 18:31-7. [PMID: 1711576 DOI: 10.1002/jemt.1060180106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Confocal laser scanning microscopy has been used to study the localization of myelin basic proteins expressed in nonglial cells, and to probe the three-dimensional structure of central auditory neurons in the lateral superior olive. The paper focuses on the techniques used to obtain the results. The key roles of confocal microscopy and computer image processing of the images obtained are emphasized as they relate to the discovery of essential structural information about these specimens.
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Affiliation(s)
- S M Staugaitis
- Department of Cell Biology, NYU Medical Center, New York 10016
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Abstract
Sonographic signs were correlated with clinical data, surgical findings, and pathology in 15 patients withtubal pregnancy. Sonograms showed absence of intrauterine gestation in 12 patients. In 3, structures resembling gestational sacs were produced by decidual reaction and blood in the uterine cavity separating the endometrial echoes. The uterus was normal in size in 6 cases. Almost all sonograms showed a pelvic mass (usually adnexal) displacing the uterus. Seven patients had predominantly sonolucent masses, 3 had complex masses, and 4 had both types. Only one woman exhibited a definite gestational sac in an extrauterine location. Four patients had a negative pregnancy test at the time of sonography. Meticulous sonographic technique and a high index of suspicion will facilitate the diagnosis of tubal pregnancy in most cases.
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Petters WJ, Schrank LW, Rowan T. Pneumatosis coli. Report of a case with perforation. Wis Med J 1977; 76:109-11. [PMID: 906550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Boddy K, Hume R, White C, Pack A, King PC, Weyers E, Rowan T, Mills E. The relation between potassium in body fluids and total body potassium in healthy and diabetic subjects. Clin Sci Mol Med 1976; 50:455-61. [PMID: 1277754 DOI: 10.1042/cs0500455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. The concentration of potassium in the erythrocytes and the plasma of forty-one normal subjects and twenty-five diabetic patients was measured and the results were used to calculate the total amount of potassium in the erythrocyte mass and the total amount of potassium in the plasma. The total body potassium was measured in a whole-body monitor. 2. In normal subjects a close correlation was found between total erythrocyte potassium and total body potassium and also between total plasma potassium and total body potassium. 3. The regression relation between total body potassium and total erythrocyte potassium in normal subjects was used to predict the total body potassium in diabetic patients. There was reasonable agreement between the measured and predicted total body potassium but there was poor agreement between the measured total body potassium and that predicted from the patient's height and age or height and age or height, weight and age.
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Boddy K, Hume R, King PC, Weyers E, Rowan T. Total body, plasma and erythrocyte potassium and leucocyte ascorbic acid in 'ultra-fit' subjects. Clin Sci Mol Med 1974; 46:449-56. [PMID: 4829860 DOI: 10.1042/cs0460449] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
1. Total body potassium was measured in professional football players before the football season began and at approximately mid-season. The values obtained were significantly higher than in healthy subjects taking only average exercise. There was a significant increase in body potassium as the season progressed.
2. Lean body mass was estimated by four methods and the results were compared. The values of lean body mass, as a percentage of body weight, were significantly higher than in healthy control subjects taking only average exercise and they also increased significantly over the period of the study.
3. The mean erythrocyte potassium concentration was lower pre-season than at mid-season and the pre-season value was also significantly less than in healthy controls. The values before and after vigorous exercise were not significantly different.
4. Conversely, the pre-season mean plasma potassium concentration was significantly higher than in control subjects and than the mid-season value. The mean plasma potassium concentration was higher before vigorous exercise than immediately afterwards.
5. The leucocyte count increased significantly after vigorous exercise, correlating with a decrease in leucocyte ascorbic acid content.
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Rowan T. Hematology Control Service of the Wisconsin Society of Pathologists. Wis Med J 1971; 70:87-8. [PMID: 5555654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Rowan T. Enzyme changes in myocardial infarction. Wis Med J 1969; 68:277-8. [PMID: 5347545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Patel AR, Paton AM, Rowan T, Lawson DH, Linton AL. Clinical studies on the effect of laevulose on the rate of metabolism of ethyl alcohol. Scott Med J 1969; 14:268-71. [PMID: 5812044 DOI: 10.1177/003693306901400803] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A study of the effect of laevulose upon the rate of metabolism of ethyl alcohol was undertaken. The rate of disappearance of ethyl alcohol from the blood of normal volunteers was estimated under normal conditions and also following the administration of oral and intravenous laevulose. These results were compared with the rate of disappearance of ethyl alcohol from the blood of inebriated patients under normal circumstances and following intravenous laevulose.The investigation confirms that ethyl alcohol is metabolised at a constant rate which varies from individual to individual and that the administration of laevulose significantly increases this rate of metabolism.It is suggested that laevulose is helpful in the management of inebriated patients in whom there is clinical suspicion of accompanying head injury.
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Rowan T, Wood HC. The biosynthesis of pteridines. V. The synthesis of riboflavin from pteridine precursors. J Chem Soc Perkin 1 1968; 4:452-8. [PMID: 5688888 DOI: 10.1039/j39680000452] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Rowan T. TREATMENT OF FRACTURE OF THE PATELLA. West J Med 1911. [DOI: 10.1136/bmj.2.2653.1234-b] [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: 11/03/2022]
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