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Mahtab S, Madewell ZJ, Madhi SA, Wise A, Swart PJ, Velaphi S, Mandomando I, Bramugy J, Mabunda R, Xerinda E, Scott AG, Assefa N, Madrid L, Bweihun M, Temesgen F, Onyango D, Akelo V, Oliech R, Otieno P, Verani JR, Arifeen SE, Gurley ES, Alam M, Rahman A, Hossain MZ, Sow S, Kotloff K, Tapia M, Keita AM, Sanogo D, Ogbuanu I, Ojulong J, Lako S, Ita O, Kaluma E, Wilson T, Mutevedzi P, Barr BAT, Whitney CG, Blau DM, Bassat Q. Stillbirths and Neonatal Deaths Caused by Group B Streptococcus in Africa and South Asia Identified Through Child Health and Mortality Prevention Surveillance (CHAMPS). Open Forum Infect Dis 2023; 10:ofad356. [PMID: 37674633 PMCID: PMC10478157 DOI: 10.1093/ofid/ofad356] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 07/10/2023] [Indexed: 09/08/2023] Open
Abstract
Background Invasive Group B Streptococcus (GBS) is a common cause of early-onset neonatal sepsis and is also associated with stillbirth. This study aimed to determine the proportion of stillborn infants and infants who died between 0 and 90 days attributable to GBS using postmortem minimally invasive tissue sampling (MITS) in 7 low- and middle-income countries (LMICs) participating in Child Health and Mortality Prevention Surveillance (CHAMPS). Methods Deaths that occurred between December 2016 and December 2021 were investigated with MITS, including culture for bacteria of blood and cerebrospinal fluid (CSF), multipathogen polymerase chain reaction on blood, CSF, and lung tissue and histopathology of lung, liver, and brain. Data collection included clinical record review and verbal autopsy. Expert panels reviewed all information and assigned causes of death. Results We evaluated 2966 deaths, including stillborn infants (n = 1322), infants who died during first day of life (0 to <24 hours, n = 597), early neonatal deaths (END) (1 day to <7 days; END; n = 593), and deaths from 7 to 90 days (n = 454). Group B Streptococcus was determined to be in the causal pathway of death for 2.7% of infants (79 of 2, 966; range, 0.3% in Sierra Leone to 7.2% in South Africa), including 2.3% (31 of 1322) of stillbirths, 4.7% (28 of 597) 0 to <24 hours, 1.9% (11 of 593) END, and 2.0% (9 of 454) of deaths from 7 to 90 days of age. Among deaths attributed to GBS with birth weight data available, 61.9% (39 of 63) of decedents weighed <2500 grams at birth. Group B Streptococcus sepsis was the postmortem diagnosis for 100% (31 of 31) of stillbirths. For deaths <90 days, postmortem diagnoses included GBS sepsis (83.3%, 40 of 48), GBS meningitis (4.2%, 2 of 48), and GBS pneumonia (2.1%, 1 of 48). Conclusions Our study reveals significant heterogeneity in the contribution of invasive GBS disease to infant mortality across different countries, emphasizing the need for tailored prevention strategies. Moreover, our findings highlight the substantial impact of GBS on stillbirths, shedding light on a previously underestimated aspect in LMICs.
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Affiliation(s)
- Sana Mahtab
- South African Medical Research Council, Vaccines Infectious Diseases and Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Zachary J Madewell
- Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Shabir A Madhi
- South African Medical Research Council, Vaccines Infectious Diseases and Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Amy Wise
- National Health for Laboratory Service in South Africa, Johannesburg, South Africa
| | - Peter J Swart
- Department of Obstetrics and Gynecology, Rahima Mossa Mother and Child Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - Sithembiso Velaphi
- Department of Pediatrics, Chris Hani Baragwanath Academic Hospital, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Inacio Mandomando
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Instituto Nacional de Saúde (INS), Maputo, Mozambique
| | - Justina Bramugy
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Rita Mabunda
- ISGlobal—Hospital Clínic, Unversitat de Barcelona, Barcelona, Spain
| | - Elisio Xerinda
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Anthony G Scott
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Nega Assefa
- College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Lola Madrid
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | | | | | - Dickens Onyango
- Kisumu County Department of Health, Ministry of Health, Kisumu, Kenya
| | - Victor Akelo
- US Centers for Disease Control and Prevention–Kenya, Kisumu, Kenya
| | - Richard Oliech
- Kenya Medical Research Institute-Center for Global Health Research (KEMRI-CGHR), Kisumu, Kenya
| | - Peter Otieno
- Kenya Medical Research Institute-Center for Global Health Research (KEMRI-CGHR), Kisumu, Kenya
| | - Jennifer R Verani
- National Center for Immunization and Respiratory Disease, Centers for Disease Control, Atlanta, Georgia, USA
| | - Shams El Arifeen
- International Center for Diarrhoeal Diseases Research (icddr, b), Dhaka, Bangladesh
| | - Emily S Gurley
- International Center for Diarrhoeal Diseases Research (icddr, b), Dhaka, Bangladesh
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Muntasir Alam
- International Center for Diarrhoeal Diseases Research (icddr, b), Dhaka, Bangladesh
| | - Afruna Rahman
- International Center for Diarrhoeal Diseases Research (icddr, b), Dhaka, Bangladesh
| | | | - Samba Sow
- Centre pour le Développement des Vaccins (CVD-Mali), Ministère de la Santé, Bamako, Mali
| | - Karen Kotloff
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Milagritos Tapia
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Adama Mamby Keita
- Centre pour le Développement des Vaccins (CVD-Mali), Ministère de la Santé, Bamako, Mali
| | - Doh Sanogo
- Centre pour le Développement des Vaccins (CVD-Mali), Ministère de la Santé, Bamako, Mali
| | | | | | - Sandra Lako
- Aberdeen Women's Centre in Freetown, Sierra Leone
| | | | | | - Tais Wilson
- Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Portia Mutevedzi
- Emory Global Health Institute, Emory University, Atlanta, Georgia, USA
| | - Beth A Tippett Barr
- Kenya Medical Research Institute-Center for Global Health Research (KEMRI-CGHR), Kisumu, Kenya
| | - Cynthia G Whitney
- Emory Global Health Institute, Emory University, Atlanta, Georgia, USA
| | - Dianna M Blau
- Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Quique Bassat
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- ISGlobal—Hospital Clínic, Unversitat de Barcelona, Barcelona, Spain
- Institutó Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain
- Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain
- Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
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Baillie VL, Moore DP, Mathunjwa A, Baggett HC, Brooks A, Feikin DR, Hammitt LL, Howie SRC, Knoll MD, Kotloff KL, Levine OS, O’Brien KL, Scott AG, Thea DM, Antonio M, Awori JO, Driscoll AJ, Fancourt NSS, Higdon MM, Karron RA, Morpeth SC, Mulindwa JM, Murdoch DR, Park DE, Prosperi C, Rahman MZ, Rahman M, Salaudeen RA, Sawatwong P, Somwe SW, Sow SO, Tapia MD, Simões EAF, Madhi SA. Epidemiology of the Rhinovirus (RV) in African and Southeast Asian Children: A Case-Control Pneumonia Etiology Study. Viruses 2021; 13:v13071249. [PMID: 34198998 PMCID: PMC8310211 DOI: 10.3390/v13071249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 11/16/2022] Open
Abstract
Rhinovirus (RV) is commonly detected in asymptomatic children; hence, its pathogenicity during childhood pneumonia remains controversial. We evaluated RV epidemiology in HIV-uninfected children hospitalized with clinical pneumonia and among community controls. PERCH was a case-control study that enrolled children (1–59 months) hospitalized with severe and very severe pneumonia per World Health Organization clinical criteria and age-frequency-matched community controls in seven countries. Nasopharyngeal/oropharyngeal swabs were collected for all participants, combined, and tested for RV and 18 other respiratory viruses using the Fast Track multiplex real-time PCR assay. RV detection was more common among cases (24%) than controls (21%) (aOR = 1.5, 95%CI:1.3–1.6). This association was driven by the children aged 12–59 months, where 28% of cases vs. 18% of controls were RV-positive (aOR = 2.1, 95%CI:1.8–2.5). Wheezing was 1.8-fold (aOR 95%CI:1.4–2.2) more prevalent among pneumonia cases who were RV-positive vs. RV-negative. Of the RV-positive cases, 13% had a higher probability (>75%) that RV was the cause of their pneumonia based on the PERCH integrated etiology analysis; 99% of these cases occurred in children over 12 months in Bangladesh. RV was commonly identified in both cases and controls and was significantly associated with severe pneumonia status among children over 12 months of age, particularly those in Bangladesh. RV-positive pneumonia was associated with wheezing.
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Affiliation(s)
- Vicky L. Baillie
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa; (D.P.M.); (A.M.); (E.A.F.S.); (S.A.M.)
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases Unit, University of the Witwatersrand, Johannesburg 1864, South Africa
- Correspondence: ; Tel.: +27-(11)-9834283
| | - David P. Moore
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa; (D.P.M.); (A.M.); (E.A.F.S.); (S.A.M.)
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases Unit, University of the Witwatersrand, Johannesburg 1864, South Africa
- Department of Paediatrics & Child Health, Chris Hani Baragwanath Academic Hospital and University of the Witwatersrand, Johannesburg 1864, South Africa
| | - Azwifarwi Mathunjwa
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa; (D.P.M.); (A.M.); (E.A.F.S.); (S.A.M.)
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases Unit, University of the Witwatersrand, Johannesburg 1864, South Africa
| | - Henry C. Baggett
- Division of Global Health Protection, Thailand Ministry of Public Health–U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi 11000, Thailand; (H.C.B.); (P.S.)
- Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Abdullah Brooks
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA;
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka and Matlab, Bangladesh; (M.Z.R.); (M.R.)
| | - Daniel R. Feikin
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
- Division of Viral Diseases, National Center for Immunizations and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Laura L. Hammitt
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi 80108, Kenya; (A.G.S.); (J.O.A.); (S.C.M.)
| | - Stephen R. C. Howie
- Medical Research Council Unit at the London School of Hygiene and Tropical Medicine, Basse 273, The Gambia; (S.R.C.H.); (M.A.); (R.A.S.)
- Department of Paediatrics: Child & Youth Health, University of Auckland, Park Rd, Auckland 1023, New Zealand
| | - Maria Deloria Knoll
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Karen L. Kotloff
- Division of Infectious Disease and Tropical Pediatrics, Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21205, USA; (K.L.K.); (M.D.T.)
| | - Orin S. Levine
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Katherine L. O’Brien
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Anthony G. Scott
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi 80108, Kenya; (A.G.S.); (J.O.A.); (S.C.M.)
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Donald M. Thea
- Department of Global Health, Boston University School of Public Health, Boston, MA 02118, USA;
| | - Martin Antonio
- Medical Research Council Unit at the London School of Hygiene and Tropical Medicine, Basse 273, The Gambia; (S.R.C.H.); (M.A.); (R.A.S.)
- Department of Pathogen Molecular Biology, London School of Hygiene & Tropical Medicine, Microbiology and Infection Unit, Warwick Medical School, University of Warwick, Coventry CV4 7JJ, UK
| | - Juliet O. Awori
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi 80108, Kenya; (A.G.S.); (J.O.A.); (S.C.M.)
| | - Amanda J. Driscoll
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21205, USA
| | - Nicholas S. S. Fancourt
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Melissa M. Higdon
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Ruth A. Karron
- Department of International Health, Center for Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA;
| | - Susan C. Morpeth
- Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi 80108, Kenya; (A.G.S.); (J.O.A.); (S.C.M.)
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
- Microbiology Laboratory, Middlemore Hospital, Counties Manukau District Health Board, Auckland 1640, New Zealand
| | - Justin M. Mulindwa
- Department of Paediatrics and Child Health, University Teaching Hospital, Lusaka 50110, Zambia; (J.M.M.); (S.W.S.)
| | - David R. Murdoch
- Department of Pathology and Biomedical Sciences, University of Otago, Christchurch 8011, New Zealand;
- Microbiology Unit, Canterbury Health Laboratories, Christchurch 8140, New Zealand
| | - Daniel E. Park
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
- Milken Institute School of Public Health, Department of Epidemiology, George Washington University, Washington, DC 20052, USA
| | - Christine Prosperi
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; (D.R.F.); (L.L.H.); (M.D.K.); (O.S.L.); (K.L.O.); (A.J.D.); (N.S.S.F.); (M.M.H.); (D.E.P.); (C.P.)
| | - Mohammed Ziaur Rahman
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka and Matlab, Bangladesh; (M.Z.R.); (M.R.)
| | - Mustafizur Rahman
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka and Matlab, Bangladesh; (M.Z.R.); (M.R.)
| | - Rasheed A. Salaudeen
- Medical Research Council Unit at the London School of Hygiene and Tropical Medicine, Basse 273, The Gambia; (S.R.C.H.); (M.A.); (R.A.S.)
- Medical Microbiology Department, Lagos University Teaching Hospital, Lagos 100254, Nigeria
| | - Pongpun Sawatwong
- Division of Global Health Protection, Thailand Ministry of Public Health–U.S. Centers for Disease Control and Prevention Collaboration, Nonthaburi 11000, Thailand; (H.C.B.); (P.S.)
| | - Somwe Wa Somwe
- Department of Paediatrics and Child Health, University Teaching Hospital, Lusaka 50110, Zambia; (J.M.M.); (S.W.S.)
| | - Samba O. Sow
- Centre pour le Développement des Vaccins (CVD-Mali), Bamako 198, Mali;
| | - Milagritos D. Tapia
- Division of Infectious Disease and Tropical Pediatrics, Department of Pediatrics, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21205, USA; (K.L.K.); (M.D.T.)
| | - Eric A. F. Simões
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa; (D.P.M.); (A.M.); (E.A.F.S.); (S.A.M.)
- Department of Pediatrics, University of Colorado School of Medicine and Center for Global Health, Colorado School of Public Health, Aurora, CO 80309, USA
| | - Shabir A. Madhi
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa; (D.P.M.); (A.M.); (E.A.F.S.); (S.A.M.)
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases Unit, University of the Witwatersrand, Johannesburg 1864, South Africa
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3
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Than MP, Pickering JW, Dryden JM, Lord SJ, Aitken SA, Aldous SJ, Allan KE, Ardagh MW, Bonning JWN, Callender R, Chapman LRE, Christiansen JP, Cromhout APJ, Cullen L, Deely JM, Devlin GP, Ferrier KA, Florkowski CM, Frampton CMA, George PM, Hamilton GJ, Jaffe AS, Kerr AJ, Larkin GL, Makower RM, Matthews TJE, Parsonage WA, Peacock WF, Peckler BF, van Pelt NC, Poynton L, Richards AM, Scott AG, Simmonds MB, Smyth D, Thomas OP, To ACY, Du Toit SA, Troughton RW, Yates KM. ICare-ACS (Improving Care Processes for Patients With Suspected Acute Coronary Syndrome): A Study of Cross-System Implementation of a National Clinical Pathway. Circulation 2017; 137:354-363. [PMID: 29138293 DOI: 10.1161/circulationaha.117.031984] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 10/10/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Efforts to safely reduce length of stay for emergency department patients with symptoms suggestive of acute coronary syndrome (ACS) have had mixed success. Few system-wide efforts affecting multiple hospital emergency departments have ever been evaluated. We evaluated the effectiveness of a nationwide implementation of clinical pathways for potential ACS in disparate hospitals. METHODS This was a multicenter pragmatic stepped-wedge before-and-after trial in 7 New Zealand acute care hospitals with 31 332 patients investigated for suspected ACS with serial troponin measurements. The implementation was a clinical pathway for the assessment of patients with suspected ACS that included a clinical pathway document in paper or electronic format, structured risk stratification, specified time points for electrocardiographic and serial troponin testing within 3 hours of arrival, and directions for combining risk stratification and electrocardiographic and troponin testing in an accelerated diagnostic protocol. Implementation was monitored for >4 months and compared with usual care over the preceding 6 months. The main outcome measure was the odds of discharge within 6 hours of presentation RESULTS: There were 11 529 participants in the preimplementation phase (range, 284-3465) and 19 803 in the postimplementation phase (range, 395-5039). Overall, the mean 6-hour discharge rate increased from 8.3% (range, 2.7%-37.7%) to 18.4% (6.8%-43.8%). The odds of being discharged within 6 hours increased after clinical pathway implementation. The odds ratio was 2.4 (95% confidence interval, 2.3-2.6). In patients without ACS, the median length of hospital stays decreased by 2.9 hours (95% confidence interval, 2.4-3.4). For patients discharged within 6 hours, there was no change in 30-day major adverse cardiac event rates (0.52% versus 0.44%; P=0.96). In these patients, no adverse event occurred when clinical pathways were correctly followed. CONCLUSIONS Implementation of clinical pathways for suspected ACS reduced the length of stay and increased the proportions of patients safely discharged within 6 hours. CLINICAL TRIAL REGISTRATION URL: https://www.anzctr.org.au/ (Australian and New Zealand Clinical Trials Registry). Unique identifier: ACTRN12617000381381.
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Affiliation(s)
- Martin P Than
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | - John W Pickering
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.).,Department of Medicine, Christchurch Heart Institute, University of Otago, New Zealand (J.W.P., C.M.A.F., P.M.G., A.M.R., R.W.T.)
| | - Jeremy M Dryden
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | - Sally J Lord
- Department of Epidemiology and Medical Statistics, University of Notre Dame, Sydney Campus, New South Wales, Australia (S.J.L.)
| | | | - Sally J Aldous
- Department of Cardiology (S.J.A., D.S., R.W.T.), Christchurch Hospital, New Zealand.,National Health and Medical Research Council Clinical Trials Centre, University of Sydney, New South Wales, Australia (S.J.L.)
| | | | - Michael W Ardagh
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | | | - Rosie Callender
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | | | | | | | | | - Joanne M Deely
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | | | | | | | - Christopher M A Frampton
- Department of Medicine, Christchurch Heart Institute, University of Otago, New Zealand (J.W.P., C.M.A.F., P.M.G., A.M.R., R.W.T.)
| | - Peter M George
- Department of Medicine, Christchurch Heart Institute, University of Otago, New Zealand (J.W.P., C.M.A.F., P.M.G., A.M.R., R.W.T.)
| | - Gregory J Hamilton
- Planning and Funding, Canterbury District Health Board, Christchurch, New Zealand (G.J.H.)
| | - Allan S Jaffe
- Department of Cardiology, Mayo Clinic, Rochester, MN (A.S.J.)
| | - Andrew J Kerr
- Department of Emergency Medicine, Baylor College of Medicine, Houston, TX (A.J.K., W.F.P.)
| | - G Luke Larkin
- Department of Emergency Medicine (G.L.L.), Auckland University, New Zealand
| | | | - Timothy J E Matthews
- Department of General Medicine, Wairarapa Hospital, Masterton, New Zealand (T.J.E.M.)
| | - William A Parsonage
- Department of Cardiology (W.A.P.), Royal Brisbane and Women's Hospital, Australia
| | - W Frank Peacock
- Department of Emergency Medicine, Baylor College of Medicine, Houston, TX (A.J.K., W.F.P.)
| | | | - Niels C van Pelt
- Department of Cardiology (N.C.v.P.), Middlemore Hospital, Auckland, New Zealand
| | | | - A Mark Richards
- Department of Medicine, Christchurch Heart Institute, University of Otago, New Zealand (J.W.P., C.M.A.F., P.M.G., A.M.R., R.W.T.).,Cardiovascular Research Institute, National University of Singapore (A.M.R.)
| | - Anthony G Scott
- Cardiology (A.G.S.), North Shore Hospital, Auckland, New Zealand
| | | | - David Smyth
- Department of Cardiology (S.J.A., D.S., R.W.T.), Christchurch Hospital, New Zealand
| | - Oliver P Thomas
- Emergency Department (M.P.T., J.W.P., M.W.A., R.C., J.M.D., O.P.T., J.M.D.)
| | - Andrew C Y To
- Department of Cardiology (A.C.Y.T.), Waitakere Hospital, Auckland, New Zealand
| | - Stephen A Du Toit
- Department of Biochemistry (S.A.D.T.), Waikato Hospital, Hamilton, New Zealand
| | - Richard W Troughton
- Department of Cardiology (S.J.A., D.S., R.W.T.), Christchurch Hospital, New Zealand.,Department of Medicine, Christchurch Heart Institute, University of Otago, New Zealand (J.W.P., C.M.A.F., P.M.G., A.M.R., R.W.T.)
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4
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Edwards T, Scott AG, Munyoki G, Odera VM, Chengo E, Bauni E, Kwasa T, Sander LW, Neville BG, Newton CR. Active convulsive epilepsy in a rural district of Kenya: a study of prevalence and possible risk factors. Lancet Neurol 2008; 7:50-6. [PMID: 18068520 DOI: 10.1016/s1474-4422(07)70292-2] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Few large-scale studies of epilepsy have been done in sub-Saharan Africa. We aimed to estimate the prevalence of, treatment gap in, and possible risk factors for active convulsive epilepsy in Kenyan people aged 6 years or older living in a rural area. METHODS We undertook a three-phase screening survey of 151,408 individuals followed by a nested community case-control study. Treatment gap was defined as the proportion of cases of active convulsive epilepsy without detectable amounts of antiepileptic drugs in blood. FINDINGS Overall prevalence of active convulsive epilepsy was 2.9 per 1000 (95% CI 2.6-3.2); after adjustment for non-response and sensitivity, prevalence was 4.5 per 1000 (4.1-4.9). Substantial heterogeneity was noted in prevalence, with evidence of clustering. Treatment gap was 70.3% (65.9-74.5), with weak evidence of a difference by sex and area. Adjusted odds of active convulsive epilepsy for all individuals were increased with a family history of non-febrile convulsions (odds ratio 3.3, 95% CI 2.4-4.7; p<0.0001), family history of febrile convulsions (14.6, 6.3-34.1; p<0.0001), history of both seizure types (7.3, 3.3-16.4; p<0.0001), and previous head injury (4.1, 2.1-8.1; p<0.0001). Findings of multivariable analyses in children showed that adverse perinatal events (5.7, 2.6-12.7; p<0.0001) and the child's mother being a widow (5.1, 2.4-11.0; p<0.0001) raised the odds of active convulsive epilepsy. INTERPRETATION Substantial heterogeneity exists in prevalence of active convulsive epilepsy in this rural area in Kenya. Assessment of prevalence, treatment use, and demographic variation in screening response helped to identify groups for targeted interventions. Adverse perinatal events, febrile illness, and head injury are potentially preventable associated factors for epilepsy in this region.
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Affiliation(s)
- Tansy Edwards
- Infectious Disease Epidemiology Unit, London School of Hygiene and Tropical Medicine, London, UK
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5
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Abstract
BACKGROUND Echocardiographic indices of dyssynchrony are increasingly used to select candidates for cardiac resynchronization therapy. For widespread screening of heart failure patients, such variables need to be comparable when evaluated by different operators using different equipment. OBJECTIVE AND METHODS To evaluate the reproducibility and obtainability of echocardiographic indices of mechanical dyssynchrony, we studied 40 subjects stratified according to QRS morphology and systolic function. Two echocardiograms were performed on each patient by different sonographers on different machines and each study was analyzed by two observers. RESULTS All blood-pool and tissue Doppler indices of dyssynchrony were obtainable in over 97% of cases. Blood-pool Doppler measures were the most reproducible indices of intraventricular dyssynchrony (aortic ejection delay) and interventricular dyssynchrony (aortopulmonary difference in ejection delay). For annular tissue Doppler delays, the time to peak velocity was consistently more reproducible than the time to velocity onset. CONCLUSION Differences in the reliability of echocardiographic indices may affect their suitability as screening tests for dyssynchrony.
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6
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Dyall SC, Michael GJ, Whelpton R, Scott AG, Michael-Titus AT. Dietary enrichment with omega-3 polyunsaturated fatty acids reverses age-related decreases in the GluR2 and NR2B glutamate receptor subunits in rat forebrain. Neurobiol Aging 2006; 28:424-39. [PMID: 16500747 DOI: 10.1016/j.neurobiolaging.2006.01.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [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: 09/05/2005] [Revised: 01/10/2006] [Accepted: 01/21/2006] [Indexed: 10/25/2022]
Abstract
Ageing is associated with a decrease in the brain content of omega-3 polyunsaturated fatty acids (PUFA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and with decreased neuroplasticity. The glutamate receptor subunits GluR2 and NR2B play a significant role in forebrain synaptic plasticity. We investigated GluR2 and NR2B in the aged prefrontal cortex, hippocampus and striatum, and tested if treatment with a preparation containing EPA and DHA can reverse age-related changes. The study compared adult and old (3-4 and 24-26 month) rats, and the latter were fed a standard diet or a diet supplemented for 12 weeks with omega-3 PUFA at 270mg/kg/day (ratio EPA to DHA 1.5:1). Ageing was associated with decreases in the GluR2 and NR2B subunits in all structures. These decreases were fully reversed by omega-3 PUFA supplementation. Age-related changes in the phospholipid PUFA content were also seen. Decreases in DHA were mostly corrected by supplementation. This study supports the neuroprotective effect of omega-3 fatty acids in brain ageing, and illustrates specific mechanisms underlying this effect.
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Affiliation(s)
- S C Dyall
- Neuroscience Centre, Institute of Cell and Molecular Sciences, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary, University of London, Whitechapel, London, United Kingdom.
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7
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Bakshi TK, Choo M, Edwards CC, Scott AG, Hart HH, Armstrong GP. Tachycardia causes troponin elevation despite normal coronary arteries. Heart Lung Circ 2003. [DOI: 10.1046/j.1443-9506.2003.01466.x] [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: 11/20/2022]
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8
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Bakshi TK, Choo M, Edwards CC, Scott AG, Hart HH, Armstrong GP. Causes of elevated troponin with normal coronary angiogram. Heart Lung Circ 2003. [DOI: 10.1046/j.1443-9506.2003.01533.x] [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: 11/20/2022]
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9
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Abstract
BACKGROUND The new definition of myocardial infarction (MI) emphasizes the pre-eminent role of troponin for diagnosis. Troponin rise indicates myocardial injury, but is not synonymous with infarction or ischaemia. AIMS To review the precipitating event for troponin elevation in patients with angiographically normal coronary arteries, in a district general hospital. METHODS Consecutive patients with elevated troponin I (TnI) who underwent angiography for suspected coronary disease were included in the present study if they had normal or mild disease (<50% diameter loss without complex features or thrombus). Precipitating event for TnI elevation was assigned on the totality of clinical evidence. RESULTS Twenty-one patients qualified, with an average age of 50 years (range 33-73). Sixty-two per cent of participants were female. Troponin release was attributed to tachycardia in six patients, only two of whom had haemodynamic compromise. Physical exertion was the precipitating factor in two patients; pericarditis in two patients; and severe congestive heart failure in one patient. Ten of 21 patients had no identifiable cause for a rise in TnI concentration. Five of 21 patients had left-ventricular wall motion abnormalities. There were no deaths or MI at 41 +/- 24 weeks follow up. CONCLUSION Troponin is a sensitive marker of myocardial injury and may rise following apparently minor insults. A rise in TnI concentration may have a cause other than acute coronary syndrome and may occur without significant angiographic coronary artery disease.
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Affiliation(s)
- T K Bakshi
- North Shore Hospital, Auckland, New Zealand
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10
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Duve H, Johnsen AH, Maestro JL, Scott AG, Jaros PP, Thorpe A. Isolation and identification of multiple neuropeptides of the allatostatin superfamily in the shore crab Carcinus maenas. Eur J Biochem 1997; 250:727-34. [PMID: 9461295 DOI: 10.1111/j.1432-1033.1997.00727.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
20 neuropeptides belonging to the allatostatin superfamily were isolated from extracts of cerebral and thoracic ganglia of the shore crab Carcinus maenas. They were purified by HPLC, monitored by radioimmunoassay and identified by mass spectrometry and amino acid sequencing. The allatostatins are characterised by a common C-terminal pentapeptide sequence -YXFGL-NH2. Previously such peptides have only been reported from insects. In insects the variable post-tyrosyl residue is restricted to Ala, Asn, Asp, Gly or Ser. In C. maenas, however, there are only two types; thirteen of the peptides having a post-tyrosyl Ala and the other seven, a post-tyrosyl Ser. The crab peptides include the shortest allatostatins so far identified (YAFGL-NH2 and YSFGL-NH2) as well as the longest, a 27-residue peptide. The total of 20 peptides exceeds the highest number of allatostatins found in any of the insects investigated so far (14 in Periplaneta americana). It is of interest that, despite their clear homology, none of the peptides of C. maenas is identical to any of the more than 50 known insect allatostatins. The crab allatostatins show evidence of gene duplication and mutation that has resulted in several sub-groups with close structural similarities. For example, there are four heptapeptides with the common C-terminus -PYAFGL-NH2 that differ only at the N-terminal residue, which is either Glu, Asp, Asn or Ser. Other motifs, variously extended at the N-terminus, include -GPY(A/S)FGL-NH2 (three peptides), -DMY(A/S)FGL-NH2 (three peptides), and -GQY(A/S)FGL-NH2 (two peptides). Unique among the allatostatin superfamily, one of the crab peptides has a Tyr for Phe substitution at position three from the C-terminus (GGPYSYGL-NH2). Immunocytochemistry has provided clues to the functions of the allatostatins in crustaceans by showing their widespread presence in the central and stomatogastric nervous systems.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, England
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11
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Duve H, Johnsen AH, Maestro JL, Scott AG, Crook N, Winstanley D, Thorpe A. Identification, tissue localisation and physiological effect in vitro of a neuroendocrine peptide identical to a dipteran Leu-callatostatin in the codling moth Cydia pomonella (Tortricidae: Lepidoptera). Cell Tissue Res 1997; 289:73-83. [PMID: 9182602 DOI: 10.1007/s004410050853] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [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: 02/04/2023]
Abstract
A neuroendocrine peptide of the Leu-callatostatin family, LPVYNFGL-NH2, has been isolated from tissue extracts of 5th instar larvae of the codling moth, Cydia pomonella (Lepidoptera). It is identical to a peptide previously isolated from the blowfly, Calliphora vomitoria (Diptera). The distribution of this peptide within the tissues of C. pomonella has been mapped by immunocytochemistry using antisera raised against LPVYNFGL-NH2. Midgut endocrine cells contain Leu-callatostatin immunoreactivity, as do several paired Leu-callatostatin neurones in the brain and ventral nerve cord. Within the visceral nervous system, the frontal ganglion contains four Leu-callatostatin neurones. Axons from these cells combine with others originating from neurones in the brain and project within the nervi cardiostomatogastrici to innervate the tissues of the foregut. In particular, the oesophageal valve has a prominent ring of Leu-callatostatin-immunoreactive fibres. The synthetic peptide, LPVYNFGL-NH2, has a potent reversible inhibitory effect in vitro on all visible forms of spontaneous contractile activity of the foregut, including closure of the oesophageal valve. Complete myoinhibition is observed at peptide concentrations from 10(-10 )to 10(-16) M. These results, in conjunction with the results of similar studies on cockroaches, crickets and flies, suggest that the Leu-callatostatins are a ubiquitous family of insect neuroendocrine peptides with an important role in the control of gut motility.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, E1 4NS, UK
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12
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Abstract
We have examined cross-resistance between trypanocidal drugs using a well-characterised drug-sensitive line, 247, and its cymelarsan-resistant derivative, 247melCyR. The cymelarsan-resistant line was cross-resistant to trimelarsen and melarsen oxide, and partially cross-resistant to two diamidines, pentamidine and berenil (diminazene aceturate). It was cross-resistant to lipid-soluble melarsoprol in vivo but to only a trivial degree in two in vitro assays. The potential role of adenosine transport in arsenical-induced killing of parasites was investigated. Adenosine, adenine, and the diamidines, but not inosine, were able to inhibit killing of drug-sensitive STIB 247 trypanosomes by cymelarsan and melarsen oxide in a concentration-dependent manner. These results are consistent with the view that these arsenical compounds enter trypanosomes via an adenosine-specific transporter. Melarsoprol-induced killing of trypanosomes was unaffected, however, by either purine and to only a slight degree by the diamidines. These data suggest that melarsoprol can enter trypanosomes by a route other than through an adenosine transporter and that there may be two mechanisms contributing to arsenical resistance in this drug-resistant line of trypanosomes.
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Affiliation(s)
- A G Scott
- Division of Infection and Immunity, University of Glasgow, United Kingdom
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13
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Abstract
Peptides of the allatostatin superfamily with the C-terminal amino acid sequence -YXFGL-NH2 have been isolated and identified from the lepidopterans, the codling moth, Cydia pomonella (Tortricidae) and the bollworm, Helicoverpa armigera (Noctuidae). The peptides, designated cydiastatins and helicostatins respectively, were monitored during purification with radioimmunoassays based on the callatostatins of the blowfly Calliphora vomitoria. The eight peptides from each of the two species appear to form an homologous series with four identical and three that differ by a single amino acid. This study demonstrates the ubiquitous nature of this family of peptides in insects.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary & Westfield College, University of London, UK
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14
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Duve H, Johnsen AH, Maestro JL, Scott AG, East PD, Thorpe A. Identification of the dipteran Leu-callatostatin peptide family: the pattern of precursor processing revealed by isolation studies in Calliphora vomitoria. Regul Pept 1996; 67:11-9. [PMID: 8952000 DOI: 10.1016/s0167-0115(96)00108-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Information from the Leu-callatostatin gene sequences of the blowflies Calliphora vomitoria and Lucilia cuprina was used to develop antisera specific for the variable post-tyrosyl amino-acid residues Ser, Ala and Asn of the common Leu-callatostatin C-terminal pentapeptide sequence -YXFGL-NH2. Radioimmunoassays based on these antisera were used to purify peptides from an extract of 40000 blowfly heads. Five neuropeptides of the Leu-callatostatin family were identified. Three have a seryl residue in the post-tyrosyl position. Two of these are octapeptides that differ only at the N-terminal residue; NRPYSFGL-NH2 and ARPYSFGL-NH2, whilst the third is the heptapeptide derived by N-terminal trimming; RPYSFGL-NH2. Two octapeptides in which X is Ala and Asn were also identified; VERYAFGL-NH2 and LPVYNFGL-NH2. The latter peptide is derived by processing at the internal dibasic site of a putative heneicosapeptide encoded by the DNA. These findings stress the necessity to have putative structures verified at the peptide level. Potent, reversible inhibitory effects on the spontaneous contractile activity of the blowfly rectum were recorded for ARPYSFGL-NH2 (monophasic dose-response curve with an IC50 = 10 fM) and for LPVYNFGL-NH2 (biphasic dose-response curve with IC50 values of approximately 1 fM and 1 nM). It is suggested that regulation of gut motility in insects, rather than an allatostatic function, may represent an ancestral and universal function of the allatostatins. One of the reasons for the large number of members of the Leu-callatostatin family appears to be in the provision of an integrated form of gut motility control, with different peptides controlling specific regions of the gut.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, UK
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15
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Abstract
Two cloned drug-sensitive stocks of Trypanosoma brucei (STIB 247 and STIB 386) were each used to generate cloned lines expressing resistance to the melaminophenyl arsenical drug cymelarsan (247MelCyR and 386MelCyR) and to suramin (247SurR and 386SurR). The drug-resistance phenotypes were stable after passaging in mice in the absence of drug pressure and three of the lines were transmitted through tsetse flies with no alteration of drug-resistance. There was no evidence of cross-resistance between melCy and suramin in vivo. Twenty-four hour growth inhibition assays were conducted on bloodstream and procyclic forms in axenic in vitro cultures. Suramin-resistance was expressed in bloodstream forms but not in the procyclic stage, while the melCy-resistant lines expressed melCy-resistance in both stages. No cross-resistance between melCy and suramin was observed. Cross-resistance between melCy and another arsenical drug, melB (melarsoprol), was observed in vivo, but to only a very limited extent in vitro. We propose that this difference between the in vivo and in vitro results for melB may indicate that an alteration in a surface adenosine transporter responsible for reduced melCy uptake was bypassed by melB over 24 hours in vitro.
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Affiliation(s)
- A G Scott
- Parasitology Laboratory, University of Glasgow, UK.
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Malhotra S, Scott AG, Zavorotinskaya T, Albritton LM. Analysis of the murine ecotropic leukemia virus receptor reveals a common biochemical determinant on diverse cell surface receptors that is essential to retrovirus entry. J Virol 1996; 70:321-6. [PMID: 8523543 PMCID: PMC189820 DOI: 10.1128/jvi.70.1.321-326.1996] [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: 01/31/2023] Open
Abstract
Two residues, tyrosine 235 and glutamic acid 237, of the ecotropic murine leukemia virus receptor (ATRC1) have been shown to be essential for receptor-mediated virus envelope binding and entry. We performed genetic analyses to examine the biochemical contribution of these residues in a productive virus-receptor interaction. Altered ATRC1 receptors bearing either a phenylalanine, a tryptophan, a histidine, or a methionine at position 235 mediated ecotropic virus entry comparable to that mediated by ATRC1. In contrast, altered ATRC1 receptors bearing alanine, threonine, serine, or proline at position 235 exhibited a 300- to 10,000-fold decrease in receptor capability. Furthermore, substitution of tyrosine or phenylalanine into the corresponding position (242) of the homologous human protein that lacks ecotropic virus receptor capability resulted in acquisition of ecotropic virus receptor function comparable to that of ATRC1. Substitution of a tryptophan or a histidine at that position of the human protein, however, resulted in a much-reduced receptor capability, suggesting a preference for a benzene ring in the hydrophobic side chain. A similar analysis of proteins substituted at position 237 revealed that aspartic acid, but not arginine or lysine, can functionally substitute for glutamic acid 237 in ATRC1 or at the corresponding position in the human protein. These results suggest a requirement for an acidic and a nearby hydrophobic amino acid for efficient ecotropic virus entry. Similar motifs have been identified in the virus binding sites of other retrovirus receptors, suggesting that the initial step of retrovirus entry may be governed by a common mechanism.
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Affiliation(s)
- S Malhotra
- Department of Microbiology & Immunology, College of Medicine, University of Tennessee, Memphis 38163, USA
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Duve H, Thorpe A, Scott AG, Johnsen AH, Rehfeld JF, Hines E, East PD. The sulfakinins of the blowfly Calliphora vomitoria. Peptide isolation, gene cloning and expression studies. Eur J Biochem 1995; 232:633-40. [PMID: 7556217 DOI: 10.1111/j.1432-1033.1995.tb20854.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The nonapeptide, Phe-Asp-Asp-Tyr(SO3)-Gly-His-Met-Arg-Phe-NH2 was isolated from heads of the blowfly Calliphora vomitoria. Designated callisulfakinin I, the peptide is identical to the earlier known drosulfakinin I of Drosophila melanogaster and to neosulfakinin I of Neobellieria bullata. It belongs to the sulfakinin family, all known members of which (from flies, cockroaches and locusts) have the C-terminal heptapeptide sequence Asp-Tyr(SO3)-Gly-His-Met-Arg-Phe-NH2. The callisulfakinin gene of C. vomitoria was cloned and sequenced. In addition to callisulfakinin I, the DNA revealed a coding sequence for the putative tetradecapeptide. Gly-Gly-Glu-Glu-Gln-Phe-Asp-Asp-Tyr-Gly-His- Met-Arg-Phe-NH2, callisulfakinin II. However, this peptide was not identified in the fly head extracts. Confocal laser scanning immunocytochemical studies with antisera raised against the synthetic undecapeptide C-terminal fragment of drosulfakinin II from D. melanogaster, Asp-Gln-Phe-Asp-Asp-Tyr(SO3)- Gly-His-Met-Arg-Phe-NH2, revealed only four pairs of sulfakinin neurones in the brain of C. vomitoria and no others anywhere else in the neural, endocrine or gut tissues. In situ hybridisation studies with a digoxigenin-labelled sulfakinin gene probe (from the blowfly Lucilia cuprina) also revealed only four pairs of neurones in the brain. The perikarya of two pairs of cells are situated medially in the caudo-dorsal region, close to the roots of the ocellar nerve. The other perikarya are slightly more posterior and lateral. Although it has been suggested by several authors that the insect sulfakinins are homologous to the vertebrate peptides gastrin and cholecystokinin, such arguments (based essentially on C-terminal structural similarities) do not take account of important differences in the C-terminal tetrapeptide. His-Met-Arg-Phe-NH2 in the sulfakinins, compared with Trp-Met-Asp-Phe-NH2 in gastrin and cholecystokinin. Furthermore, whereas the sulfakinin neurons of C. vomitoria are small in number and have a very specialised location, a greater number of cells throughout the nervous system react positively to gastrin/cholecystokinin antisera. Chromatographic profiles of the present study also revealed peaks of gastrin/cholecystokinin-immunoreactive material separate from the sulfakinin peptides. This evidence suggests that the insect and vertebrate peptides may not necessarily be homologous.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary & Westfield College, University of London, England
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Duve H, Johnsen AH, Scott AG, Thorpe A. Isolation, identification and functional significance of [Hyp2]Met-callatostatin and des Gly-Pro Met-callatostatin, two further post-translational modifications of the blowfly neuropeptide Met-callatostatin. Regul Pept 1995; 57:237-45. [PMID: 7480873 DOI: 10.1016/0167-0115(95)00037-c] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Two post-translationally modified neuropeptides of the Met-callatostatin (Gly-Pro-Pro-Tyr-Asp-Phe-Gly-Met-NH2) family have been identified from head extracts of the blowfly Calliphora vomitoria. They are the octapeptide, [Hyp2]Met-callatostatin, (Gly-Hyp-Pro-Tyr-Asp-Phe-Gly-Met-NH2) and the truncated hexapeptide, des Gly-Pro Met-callatostatin (Pro-Tyr-Asp-Phe-Gly-Met-NH2). The existence of the [Hyp2]Met-callatostatin variant, in addition to the previously identified [Hyp3]Met-callatostatin peptide, suggests that the motif for prolyl hydroxylation in C. vomitoria is more variable than those known from mammalian and other invertebrate studies where, in those regulatory peptides containing a pair of adjacent prolyl residues so far studied, e.g., bradykinin, and the mosquito peptide Aea HP-I, only one of the pair (the second) is known to undergo hydroxylation. The truncated hexapeptide, des Gly-Pro Met-callatostatin could be produced as a result of the action of a dipeptidyl peptidase II type of enzyme which is known from mammalian studies to be unique in its ability to cleave between the two prolyl residues of an Xaa-Pro-Pro- sequence, where Xaa is any unprotected NH2-terminal amino acid. This enzyme is, however, considered unlikely to be able to cleave the Gly-Hyp-Pro-sequence, which would suggest a functional significance for such a post-translational modification. For this reason, it is of interest that [Hyp2]Met-callatostatin (and earlier, [Hyp3]Met-callatostatin) have been shown to be potent inhibitors of the spontaneous contractions of the hindgut of C. vomitoria (biphasic dose-response curve with IC50 values of 10(-14) M and 10(-7) M).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, UK
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Duve H, Johnsen AH, Scott AG, East P, Thorpe A. [Hyp3]Met-callatostatin. Identification and biological properties of a novel neuropeptide from the blowfly Calliphora vomitoria. J Biol Chem 1994; 269:21059-66. [PMID: 8063725] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A novel, hydroxyproline-containing neuropeptide, Gly-Pro-Hyp-Tyr-Asp-Phe-Gly-Met-NH2, designated [HYP3]Met-callatostatin, has been identified from extracts of heads of the blowfly Calliphora vomitoria. The peptide is a naturally occurring hydroxylate analogue of Met-callatostatin, a previously identified allatostatin-like peptide, and is present to the extent of 20% of the nonhydroxylated form. In bioassays, both forms of the peptide show allatostatic activity by inhibiting juvenile hormone synthesis and release in the cockroaches Periplaneta americana, Diploptera punctata, and Blattella germanica (IC50 = 100 pM-10 nM). They do not, however, influence juvenile hormone bisepoxide synthesis and release in the blowfly. In flies, [Hyp3]Met-callatostatin inhibits the peristaltic movements of the hindgut, showing a biphasic response (IC50 = 0.5 pM and 0.5 microM) compared with the monophasic response of Met-callatostatin (IC50 = 100 nM). Immunocytochemical studies with Met-callatostatin antisera provide the cytological basis for a myoinhibitory role in the gut since the axons of immunoreactive neurons in the abdominal ganglion project to the ileum. There are also endocrine cells in the midgut that, by releasing the peptides into the hemolymph, would allow the Met-callatostatins to fulfill a neurohormonal role on muscles of the gut and heart. In contrast, there are no Met-callatostatin neural pathways from the brain to the corpus allatum, the gland that produces juvenile hormone. NH2-terminal degradation of Met-callatostatins incubated with the hemolymph of P. americana results in cleavage of the Pro-Tyr bond giving the pentapeptide Tyr-Asp-Phe-Gly-Met-NH2 as a degradation product. In contrast, the Hyp-Tyr bond resists cleavage. With hemolymph from C. vomitoria, no immunoassayable degradation product has been observed with either peptide.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary & Westfield College, University of London, United Kingdom
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Voisey CR, White DW, Dudas B, Appleby RD, Ealing PM, Scott AG. Agrobacterium-mediated transformation of white clover using direct shoot organogenesis. Plant Cell Rep 1994; 13:309-314. [PMID: 24193827 DOI: 10.1007/bf00232627] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/1993] [Revised: 01/03/1994] [Indexed: 06/02/2023]
Abstract
White clover (Trifolium repens L.) plants from the cultivars Grasslands Huia and Grasslands Tahora have been transformed using Agrobacterium-mediated T-DNA transfer. Transgenic plants regenerated directly from cells of the cotyledonary axil. To transform white clover, shoot tips from 3 day old seedlings were co-cultivated with A. tumefaciens strain LBA4404 carrying the plasmid vector pPE64. This vector contains the neomycin phosphotransferase II gene (nptII) and β-glucuronidase reporter gene (gus) both under the control of the CaMV 35S promoter. Kanamycin-resistant plants regenerated within 42 days after transfer onto selective media. Integration of the nptII and gus genes into the white clover genome was confirmed using Southern blotting, and histochemical analysis indicated that the gus gene was expressed in a variety of tissues. In reciprocal crosses between a primary transformant and a non-transformed plant the introduced gus gene segregated as a single dominant Mendelian trait.
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Affiliation(s)
- C R Voisey
- Plant Molecular Genetics Laboratory, AgResearch, Grasslands Research Centre, Private Bag 11008, Palmerston North, New Zealand
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Abstract
This paper reviews the experience of managing 31 patients with severe dysphagia in motor neurone disease. Thirteen patients were fed nasogastrically and the remaining 18 were managed conservatively without a nasogastric tube. The introduction of nasogastric feeding led to the development of new problems in some patients, without any significant differences in survival times or relief of distressing symptoms.
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Affiliation(s)
- A G Scott
- Bethlehem Hospital, South Caulfield, Victoria
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Scott AG. Comparison of criteria to define radon-prone areas. Health Phys 1993; 64:435-436. [PMID: 8449731] [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: 05/22/2023]
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Duve H, Johnsen AH, Scott AG, Yu CG, Yagi KJ, Tobe SS, Thorpe A. Callatostatins: neuropeptides from the blowfly Calliphora vomitoria with sequence homology to cockroach allatostatins. Proc Natl Acad Sci U S A 1993; 90:2456-60. [PMID: 8460157 PMCID: PMC46106 DOI: 10.1073/pnas.90.6.2456] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.4] [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: 01/30/2023] Open
Abstract
Five neuropeptides with C-terminal amino acid sequence homology to cockroach allatostatins have been identified in the blowfly Calliphora vomitoria. Three have the same pentapeptide C-terminal amino acid sequence as allatostatin 1 of the cockroach Diploptera punctata. A hexadecapeptide designated callatostatin 1, isolated from thoracic ganglia, brains, and heads, has the sequence Asp-Pro-Leu-Asn-Glu-Glu-Arg-Arg-Ala-Asn-Arg-Tyr-Gly-Phe-Gly-Leu-NH2. Callatostatins 2 and 3 have been isolated from heads and thoracic ganglia, respectively; they comprise the last 14 and 8 residues of callatostatin 1. Callatostatin 4, isolated from thoracic ganglia, has the sequence Xaa-Arg-Pro-Tyr-Ser-Phe-Gly-Leu-NH2, where Xaa is either Asp or Asn. This peptide, with a serine substitution for glycine at position 5, has a C-terminal pentapeptide sequence identical to that of allatostatins 3 and 4 of D. punctata. Callatostatin 5, with the sequence Gly-Pro-Pro-Tyr-Asp-Phe-Gly-Met-NH2, was identified from whole flies. All five peptides inhibit juvenile hormone production by the corpora allata of D. punctata in vitro. Callatostatin 5 was the most potent allatostatin so far tested in this species, with maximum inhibition occurring at 1 nM. In contrast, none of the callatostatins or the allatostatins showed allatostatic activity in mature female C. vomitoria when tested at concentrations of 100 to 0.1 microM. In accordance with these results, immunoreactivity to an antiserum directed against the common C terminus of callatostatin 1 and allatostatin 1 was observed in the corpora allata of D. punctata but not in the corpus allatum of C. vomitoria, despite its presence in neurons of the brain. Neurons in the thoracic ganglion of C. vomitoria that are immunoreactive against this antiserum project to the hindgut, rectum, rectal papillae, and oviduct, suggestive of a function different from that of a true allatostatin.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, United Kingdom
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Duve H, Johnsen AH, Sewell JC, Scott AG, Orchard I, Rehfeld JF, Thorpe A. Isolation, structure, and activity of -Phe-Met-Arg-Phe-NH2 neuropeptides (designated calliFMRFamides) from the blowfly Calliphora vomitoria. Proc Natl Acad Sci U S A 1992; 89:2326-30. [PMID: 1549595 PMCID: PMC48650 DOI: 10.1073/pnas.89.6.2326] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [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: 12/27/2022] Open
Abstract
Thirteen neuropeptides varying in length from 7 to 11 residues and ending C-terminally in -Phe-Met-Arg-Phe-NH2 (calliFMRFamides 1-13) and one dodecapeptide ending in -Met-Ile-Arg-Phe-NH2 (calliMIRFamide 1) have been isolated from thoracic ganglia of the blowfly Calliphora vomitoria. Different repeating patterns of amino acid sequences enable the peptides to be arranged into distinct groups. One such group of five nonapeptides has the sequence Xaa-Pro-Xaa-Gln-Asp-Phe-Met-Arg-Phe-NH2. Three peptides in this group, with the N-terminal tripeptide sequences Thr-Pro-Gln-, Thr-Pro-Ser-, and Ser-Pro-Ser-, are able to induce fluid secretion from the isolated salivary gland of Calliphora at a concentration of 0.1 to 1 nM. However, two other members of this group with the N-terminal tripeptide sequences Lys-Pro-Asn- and Ala-Pro-Gly-, the latter being the most abundant peptide isolated, were inactive in this assay, as were all the other peptides isolated. This indicates that the N terminus (in addition to the C terminus as previously found for FMRFamides of other organisms) is crucial for at least some biological activities.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, United Kingdom
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Duve H, Sewell JC, Scott AG, Thorpe A. Chromatographic characterisation and biological activity of neuropeptides immunoreactive to antisera against Met5-enkephalin-Arg6-Phe7 (YGGFMRF) extracted from the blowfly Calliphora vomitoria (Diptera). Regul Pept 1991; 35:145-59. [PMID: 1758972 DOI: 10.1016/0167-0115(91)90477-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neuropeptides identified with a radioimmunoassay specific for the C-terminus of Met5-enkephalin-Arg6-Phe7 (YGGFMRF) have been extracted from nervous tissues of the blowfly Calliphora vomitoria and also from whole flies. Chromatographic characterisation, based on criteria of molecular weight, charge and hydrophobicity, reveals a complex multiplicity of immunoreactive peptides. Variations in the amounts and types of peptides found within different nervous tissues is evidence that the cellular precursor processing is selective. Physiological studies on the isolated blowfly salivary gland show that synthetic YGGFMRF is a potent secretagogue with a maximal rate of fluid secretion induced at a concentration of between 10(-13) and 10(-12) M. The tetrapeptide comprising the last four residues of the C-terminus of YGGFMRF, Phe-Met-Arg-Phe, is equally potent. However, the carboxyamidated variants, YGGFMRF-NH2 and the molluscan cardioacceleratory peptide FMRF-NH2, as well as the opioid peptides Met5- and Leu5-enkephalin, have no activity. Partially purified YGGFMRF-immunoreactive peptides from the blowfly have ED50 values in the bioassay approximating to 0.3 thoracic ganglion, 2.1 hypocerebral ganglion and 3.0 brain equivalents.
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Affiliation(s)
- H Duve
- School of Biological Sciences, Queen Mary and Westfield College, University of London, U.K
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Mair GC, Scott AG, Penman DJ, Skibinski DO, Beardmore JA. Sex determination in the genus Oreochromis : 2. Sex reversal, hybridisation, gynogenesis and triploidy in O. aureus Steindachner. Theor Appl Genet 1991; 82:153-160. [PMID: 24213059 DOI: 10.1007/bf00226206] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/1990] [Accepted: 12/05/1990] [Indexed: 06/02/2023]
Abstract
Sex ratios from 62 single-pair matings of normal broodstock O. aureus were highly heterogeneous with an overall deficit of males (41.4%). Peaks in the sex ratio frequency distribution occurred at 1∶1, 3∶5 and 1∶3 (male∶female). Hybridisation of O. aureus with O. mossambicus, O. spilums and O. niloticus produced highly variable sex ratios, suggesting a complexity of hybrid sex determination. Few valid inferences could be made regarding intraspecific sex determination from these hybrid data. Sex ratios from progeny testing of sex-reversed males (1∶3) and most sex-reversed females (1∶0) provide evidence for female heterogamety in O. aureus. Several aberrant ratios observed suggest Mendelian inheritance of an autosomal recessive gene (F,f), epistatic to the major sex-determining gene (W,Z). Sex ratios of triploids and gynogens support the hypothesis of recombination between the centromere and the major sex-determining locus. Progeny testing of a female mitogyne demonstrated the viability of a novel WW "superfemale", which gave only female offspring. Not all data could be explained by a two-factor model of sex determination. Further exceptional sex ratios may be accounted for by rare autosomal or environmental sex-modifying factors. It is concluded that O. aureus has a multifactorial mechanism of sex determination with the underlying primary mechanism of female heterogamety.
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Affiliation(s)
- G C Mair
- School of Biological Sciences, University College of Swansea, SA2 8PP, Swansea, UK
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Mair GC, Scott AG, Penman DJ, Beardmore JA, Skibinski DO. Sex determination in the genus Oreochromis : 1. Sex reversal, gynogenesis and triploidy in O. niloticus (L.). Theor Appl Genet 1991; 82:144-152. [PMID: 24213058 DOI: 10.1007/bf00226205] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/1990] [Accepted: 12/12/1990] [Indexed: 06/02/2023]
Abstract
Established techniques of genetic manipulation were used to elucidate sex-determining mechanisms in the commercially important tilapia, Oreochromis niloticus. Analysis of sex ratios from single-pair matings of normal broodstock showed these to be heterogeneous, with an asymmetrical frequency distribution. Data were homogeneous, with the exclusion of a number of broods with sex ratios not significantly different from 3∶1 (male: female), and further progeny testing revealed atypical female heterogamety in the parents of these broods. Analysis of sex ratios from complete diallele-type crosses using five males and five females demonstrated no association between male parent, female parent and progeny sex ratio. Sex ratios of gynogens (0∶1) and triploids (1∶1), and from progeny testing of sex-reversed males (0∶1) and sex-reversed females (3∶1), provide evidence for female homogamety in this species. Progeny testing of male gynogens derived from sex-reversed females demonstrated recombination between the centromere and the sex-determining locus (68.9%). Novel YY "supermales" were shown to be viable and produced all-male offspring. It was concluded that this species exhibits monofactorial, genotypic sex determination with male heterogamety. However, rare autosomal or environmental sex-modifying factors may account for occasional deviations from expected sex ratios.
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Affiliation(s)
- G C Mair
- School of Biological Sciences, University College of Swansea, SA2 8PP, Swansea, UK
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Abstract
Squirrel monkeys were tested on an indirect spatial delayed response task after subcutaneous injections of either physiological saline, 100, or 500 microgram/kg [D-Ala2] methionine enkephalinamide (DAME). During Experiment 1 monkeys completed two-choice delayed response problems with 0-, 6-, 12- and 18- sec delays; DAME significantly enhanced performance at 18-sec delays but not for the shorter delay. During Experiment 2, monkeys performed a nine-choice spatial delayed response task with 0-, 4- and 8-sec delays. In Experiment 2, low but not high doses of DAME impaired performance. Memory functions represented by a bias-free performance measure paralleled percentage correct in both experiments. Therefore, DAME effect, in enhancing and in impairing performance, were not attributable to changes in the relative number of systematic spatial errors (positional win-shift; lose-stay, position perseveration, and position preference).
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Scott AG. The distribution of average radon daughter concentrations in houses estimated from single-sample surveys. Health Phys 1983; 45:435-438. [PMID: 6885447] [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: 05/21/2023]
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Scott AG. Radon daughter deposition velocities estimated from field measurements. Health Phys 1983; 45:481-485. [PMID: 6885453] [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: 05/21/2023]
Abstract
The surface deposition rate (plateout) of unattached radon daughters was estimated from simple surface activity measurements in a number of occupied buildings, and found to be about one third of the lowest value measured in diffusion tube experiments. This low value was confirmed by surface deposition and activity measurements made in a commercial building with high radon levels, which also showed that the deposition rate was higher on walls than on floors or tables. Predictions of the ratio between airborne and surface-deposited radon daughter activity using the estimated surface deposition rate were close to the ratios observed in occupied homes. Refinements to existing models are required to explain the variability of deposition rate with surface orientation.
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Scott AG. The bias in radon daughter concentration estimates caused by concentration variations during sampling. Health Phys 1983; 44:267-271. [PMID: 6832978] [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: 05/21/2023]
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Gunning C, Scott AG. Radon and thoron daughters in housing. Health Phys 1982; 42:527-528. [PMID: 6282785] [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: 05/21/2023]
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Scott AG. A field method for measurement of radon daughters in air. Health Phys 1981; 41:403-405. [PMID: 7275629] [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: 05/21/2023]
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Abstract
Endoscopic biopsies of the bladder were stained using a simple neurohistochemical technique to demonstrate the normal cholinergic innervation. The same technique was used on patients in whom a peripheral neuropathic bladder was suspected and clear evidence of denervation obtained. It is suggested that the technique be applied to all cases where peripheral denervation is a possibility to assist in diagnosis and to select cases where long-term urological follow-up is mandatory.
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Scott AG. Letter: Childhood poisoning: the failure of aluminium foil wrapping as a preventative. N Z Med J 1976; 83:378. [PMID: 1066569] [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: 12/25/2022]
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Scott AG. The establishment of a Regional School of Nursing at Newcastle Technical College. UNA Nurs J 1973; 71:14-7. [PMID: 4492898] [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: 01/10/2023]
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Scott AG. The establishment of a regional school of nursing at Newcastle Technical College. Designing an answer. Aust Nurses J 1973; 3:29-32. [PMID: 4492025] [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: 01/10/2023]
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Scott AG, Guthrie JE. The accumulation of radioactive cesium, phosphorus, strontium, and yttrium by mosquito larvae and its relevance to radiation dose. CAN J ZOOL 1972; 50:767-70. [PMID: 5038727 DOI: 10.1139/z72-103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Aedes aegypti (L.) larvae were reared in solutions of 137Cs, 32P, and 90Sr + 90Y and the apparent concentration ratios of the individual radionuclides which were accumulated are reported. A consideration of the significance of accumulation to the internal radiation dose delivered to the larvae reveals that larvae reared in identical concentrations of a radionuclide did not receive the same dose, nor were they exposed to the greatest dose-rate at the same stage of development. The probable dose to larvae reared in radioactive solutions cannot be calculated solely from a knowledge of the radionuclide concentration in the rearing medium.
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Abstract
Thermoluminescent dosimetry has been used to measure the radiation dose accumulated by Chironomidae larvae inhabiting a 19-m diameter pond contaminated with cesium-137. Small plastic tubes filled with lithium fluoride powder were arranged in parallel rows along the pond bottom. The accumulated gamma dose was greatest at the pond margin.
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