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Toda T, Bedrosian TA, Schafer ST, Cuoco MS, Linker SB, Ghassemzadeh S, Mitchell L, Whiteley JT, Novaresi N, McDonald AH, Gallina IS, Yoon H, Hester ME, Pena M, Lim C, Suljic E, AlFatah Mansour A, Boulard M, Parylak SL, Gage FH. Long interspersed nuclear elements safeguard neural progenitors from precocious differentiation. Cell Rep 2024; 43:113774. [PMID: 38349791 PMCID: PMC10948021 DOI: 10.1016/j.celrep.2024.113774] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 11/30/2023] [Accepted: 01/24/2024] [Indexed: 02/15/2024] Open
Abstract
Long interspersed nuclear element-1 (L1 or LINE-1) is a highly abundant mobile genetic element in both humans and mice, comprising almost 20% of each genome. L1s are silenced by several mechanisms, as their uncontrolled expression has the potential to induce genomic instability. However, L1s are paradoxically expressed at high levels in differentiating neural progenitor cells. Using in vitro and in vivo techniques to modulate L1 expression, we report that L1s play a critical role in both human and mouse brain development by regulating the rate of neural differentiation in a reverse-transcription-independent manner.
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Affiliation(s)
- Tomohisa Toda
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA; Laboratory of Neural Epigenomics, Institute of Medical Physics and Micro-tissue Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; Nuclear Architecture in Neural Plasticity and Aging Laboratory, German Center for Neurodegenerative Diseases, 01307 Dresden, Germany.
| | - Tracy A Bedrosian
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA; Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Simon T Schafer
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA; Department of Psychiatry and Psychotherapy, School of Medicine and Health, Technical University of Munich, Munich, Germany; TUM Center for Organoid Systems (COS), Munich Institute of Biomedical Engineering, Garching, Germany
| | - Michael S Cuoco
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA; Computational Neural DNA Dynamics Lab, Department of Cognitive Science, University of California, San Diego, San Diego, CA, USA; Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, San Diego, CA, USA
| | - Sara B Linker
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Saeed Ghassemzadeh
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Lisa Mitchell
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jack T Whiteley
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Nicole Novaresi
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Aidan H McDonald
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Iryna S Gallina
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Hyojung Yoon
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Mark E Hester
- Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Monique Pena
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA; Department of Psychiatry and Psychotherapy, School of Medicine and Health, Technical University of Munich, Munich, Germany; TUM Center for Organoid Systems (COS), Munich Institute of Biomedical Engineering, Garching, Germany
| | - Christina Lim
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Emelia Suljic
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Abed AlFatah Mansour
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Matthieu Boulard
- Epigenetics & Neurobiology Unit, EMBL Rome, European Molecular Biology Laboratory, Via Ramarini 32, 00015 Monterotondo, Italy
| | - Sarah L Parylak
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Parylak SL, Qiu F, Linker SB, Gallina IS, Lim CK, Preciado D, McDonald AH, Zhou X, Gage FH. Neuronal activity-related transcription is blunted in immature compared to mature dentate granule cells. Hippocampus 2023; 33:412-423. [PMID: 36811254 PMCID: PMC10985790 DOI: 10.1002/hipo.23515] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/01/2023] [Accepted: 02/07/2023] [Indexed: 02/24/2023]
Abstract
Immature dentate granule cells (DGCs) generated in the hippocampus during adulthood are believed to play a unique role in dentate gyrus (DG) function. Although immature DGCs have hyperexcitable membrane properties in vitro, the consequences of this hyperexcitability in vivo remain unclear. In particular, the relationship between experiences that activate the DG, such as exploration of a novel environment (NE), and downstream molecular processes that modify DG circuitry in response to cellular activation is unknown in this cell population. We first performed quantification of immediate early gene (IEG) proteins in immature (5-week-old) and mature (13-week-old) DGCs from mice exposed to a NE. Paradoxically, we observed lower IEG protein expression in hyperexcitable immature DGCs. We then isolated nuclei from active and inactive immature DGCs and performed single-nuclei RNA-Sequencing. Compared to mature nuclei collected from the same animal, immature DGC nuclei showed less activity-induced transcriptional change, even though they were classified as active based on expression of ARC protein. These results demonstrate that the coupling of spatial exploration, cellular activation, and transcriptional change differs between immature and mature DGCs, with blunted activity-induced changes in immature cells.
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Affiliation(s)
- Sarah L Parylak
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Fan Qiu
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Sara B Linker
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Iryna S Gallina
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Christina K Lim
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - David Preciado
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Aidan H McDonald
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Xavier Zhou
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, USA
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McDonald AH. Emergency medicine--merging with other specialities: an update. W INDIAN MED J 2014; 63:213-6. [PMID: 25629692 PMCID: PMC4663906 DOI: 10.7727/wimj.2014.395] [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] [Received: 05/12/2014] [Accepted: 05/15/2014] [Indexed: 11/18/2022]
Affiliation(s)
- A H McDonald
- Emergency Medicine Division, Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica.
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McDonald AH, Murphy R. A pilot audit of a protocol for ambulatory investigation of predicted low-risk patients with possible pulmonary embolism. J R Coll Physicians Edinb 2011; 41:196-201. [DOI: 10.4997/jrcpe.2011.302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Abstract
AIM This study reviewed the operative management and outcome of patients with adult Hirschsprung's disease treated at the University Hospital of the West Indies, Mona, Jamaica. METHOD The case notes for 11 patients with adult Hirschsprung's disease, treated operatively between January 1986 and December 2007, were reviewed and data on preoperative diagnosis, operative procedures and postoperative complications were retrieved. RESULTS Diagnosis was by open rectal biopsy in nine patients and by rectal suction biopsy in two patients. The time taken for preoperative bowel preparation ranged from 10 to 35 days, and colostomy was required in three patients to facilitate bowel cleansing. The Soave and Swenson procedures were used in six and five patients, respectively, leading to anastomotic stricture in one patient treated using the Soave procedure and to leakage in two patients treated using the Swenson procedure. All procedures took longer than 300 min, and 300-800 ml of blood or plasma was transfused. CONCLUSION Therapeutic procedures for adult Hirschsprung's disease may result in life-threatening anastamotic complications. A protective colostomy is recommended when Swenson's procedure is used.
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Affiliation(s)
- N D Duncan
- Department of Surgery, University of the West Indies, Mona, Jamaica.
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Williams-Johnson JA, McDonald AH, Strachan GG, Williams EW. Effects of tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2) A randomised, placebo-controlled trial. W INDIAN MED J 2010; 59:612-624. [PMID: 21702233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND Tranexamic acid can reduce bleeding in patients undergoing elective surgery. We assessed the effects of early administration of a short course of tranexamic acid on death, vascular occlusive events, and the receipt of blood transfusion in trauma patients. METHODS This randomised controlled trial was undertaken in 274 hospitals in 40 countries. 20 211 adult trauma patients with, or at risk of significant bleeding were randomly assigned within 8 h of injury to either tranexamic acid (loading dose 1 g over 10 min then infusion of 1 g over 8 h) or matching placebo. Randomisation was balanced by centre, with an allocation sequence based on a block size of eight, generated with a computer random number generator Both participants and study staff (site investigators and trial coordinating centre staff) were masked to treatment allocation. The primary outcome was death in hospital within 4 weeks of injury, and was described with the following categories: bleeding, vascular occlusion (myocardial infarction, stroke and pulmonary embolism), multiorgan failure, head injury, and other AL analyses were by intention to treat. This study is registered as ISRCTN86750102, Clinicaltrials.gov NCT00375258, and South African Clinical Trial Register DOH-27-0607-1919. RESULTS 10096 patients were allocated to tranexamic acid and 10 115 to placebo, of whom 10060 and 10067, respectively, were analysed. All-cause mortality was significantly reduced with tranexamic acid (1463 [14.5%] tranexamic acid group vs 1613 [160%] placebo group; relative risk 0.91, 95% CI 085-097; p = 00035). The risk of death due to bleeding was significantly reduced (489 [49%] vs 574 [5-7%]; relative risk 0-85, 95% CI 0.76-0.96; p = 0-0077). CONCLUSION Tranexamic acid safely reduced the risk of death in bleeding trauma patients in this study On the basis of these results, tranexamic acid should be considered for use in bleeding trauma patients.
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Ward E, McCartney T, Arscott-Mills S, Gordon N, Grant A, McDonald AH, Ashley DE. The Jamaica Injury Surveillance System: a profile of the intentional and unintentional injuries in Jamaican hospitals. W INDIAN MED J 2010; 59:7-13. [PMID: 20931906] [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: 05/30/2023]
Abstract
BACKGROUND Injuries in Jamaica are a major public health problem as demonstrated by a hospital based computerized injury surveillance system established in 1999 that provides a risk profile for injuries. SUBJECTS AND METHOD Injury data from 2004 were selected to provide an annual profile, as comprehensive injury data were available from nine public hospitals. These nine public hospitals provide care for 70% of the Jamaicans admitted to hospitals annually. RESULTS Data are presented on unintentional injuries where falls caused 44%, lacerations 27% and accidental blunt injuries were 17% of these. For motor vehicle related injuries, 55% were sustained while commuting by motorcars, 17% while riding motorbikes/bicycles and 16% of those injured were pedestrians. Most violence related injuries were due to fights (76%) with acquaintances (47%) who used sharp objects (40%) to inflict the injury. CONCLUSION The Jamaica Injury Surveillance System (JISS) data, augmented by data collected on injuries from the health centres and the sentinel surveillance system, give a measure of the magnitude of the impact of injuries on the health services. The JISS provides data on the profile of injuries seen and treated at health facilities in Jamaica. In collaboration with police data and community-based surveys, it can be used to complete the risk profiles for different types of injuries. The data generated at the parish, regional and national levels form the basis for the design and monitoring of prevention programmes, as well as serve to support and evaluate policy, legislative control measures and measures that impact on interventions.
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Affiliation(s)
- E Ward
- Ministry of Health, Kingston, Jamaica.
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Plummer JM, Brown H, Jones K, Fearon-Boothe D, Meeks-Aitken N, McDonald AH. Trauma: the burden of a preventable problem. W INDIAN MED J 2010; 59:26-28. [PMID: 20931909] [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: 05/30/2023]
Abstract
Trauma is a leading cause of morbidity and mortality in developing countries and we reviewed the demographics and cost of trauma in a Jamaican population. This is a retrospective, descriptive analytical study of all trauma patients aged 25 to 29-years who presented to the University Hospital of the West Indies (UHWI) during the study period, January 2001 to December 2005. Data were extracted from the Trauma Registry and analysed. Seven hundred and fifteen patients were included in the specified age group over the five-year period. The median age of the patients was 27 years and the median hospital stay was 3 days. There was a 4:1 ratio of males to females and 49.7% of injuries were caused by penetrating wounds. Motor vehicle accidents occurred in 22.4% of cases. Head injuries occurred in 13.6% of cases, long bone fractures in 16.5% and internal injury to chest or abdominal organs in 15.9% of cases. Craniotomy or thoracotomy was undertaken in 4% of cases, Open Reduction Internal Fixation (ORIF) or bone immobilization in 11% and laparotomy in 8% of cases. The mean injury severity scores (ISS) was 4 while 5% of patients had ISS greater than 15. More than 60% of patients underwent diagnostic X-rays, 8% had abdominal imaging (CT scan or ultrasound) and 9.5% underwent head CT scan. The in-hospital mortality was 4.2%. The median hospital bill charged was US$320.00 and the median amount paid by the patients was US$50.00. At the start of the new millennium, penetrating trauma accounted for almost 50% of cases at UHWI with the majority of costs associated with trauma-care being state funded.
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Affiliation(s)
- J M Plummer
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Crandon IW, Harding HE, Cawich SO, McDonald AH, Fearron-Boothe D. Motorcycle accident injury profiles in Jamaica: an audit from the University Hospital of the West Indies. Int J Inj Contr Saf Promot 2009; 16:175-8. [PMID: 19941216 DOI: 10.1080/17457300903024236] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
There is little data available on the prevalence of motorcycle accidents, their resultant injuries and the demand on the health care services in Jamaica. We performed a descriptive, analytical study to evaluate the extent of this problem and the need for preventative national policy measures. Between 1 January 2000 and 1 January 2007, demographic and clinical data on all motorcycle accident victims admitted to the University Hospital of the West Indies were collected in a prospective database. The data were analysed using the SPSS version 12.0. Of 270 motorcycle accident victims, there were 257 (95.2%) males and 13 (4.8%) females. Overall, 134 (49.6%) victims wore helmets at the time of their accident. The more common injuries were as follows: soft tissue trauma 270 (100%); head injuries 143 (53.0%); long bone fractures 126 (46.7%); abdominal injuries 38 (14.1%); thoracic injuries 71 (26.3%); vascular injuries 11 (4.1%). The mean injury severity score was 9.0 (SD 9.4; Median 8; Mode 4). There were 195 patients needing surgical intervention in the form of orthopaedic operations (94), neurosurgical operations (43), abdominal operations (49) and vascular operations (14). The mean duration of hospitalisation was 10 days (SD 11.2; Range 0-115; Median 6; Mode 3). There were 12 (4.4%) deaths, 9 (75%) due to traumatic brain injuries. Fatal injuries were more common in males (11) and un-helmeted patients (10). Motorcycle accidents take a heavy toll on this health care facility in Jamaica. Measures to prevent motorcycle accidents and reduce consequent injuries may be one way in which legislators can preserve precious resources that are spent during these incidents. This can be achieved through active measures such as educational campaigns, adherence to traffic regulations and enforcement of helmet laws.
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Affiliation(s)
- I W Crandon
- Section of Surgery, Department of Surgery, Radiology and Anaesthesia, University of the West Indies, Jamaica
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Williams EW, Williams-Johnson J, McDonald AH, French S, Hutson R, Singh P, Sadock J, Butchey R, Ellis M, Thompson C, Espinosa K. The evolution of emergency medicine in Jamaica. W INDIAN MED J 2008; 57:161-165. [PMID: 19565961] [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: 05/28/2023]
Abstract
Emergency Medicine in Jamaica has evolved rapidly over the past 20 years and has gained recognition as a specialty. A residency training programme has been established, trademark life support courses are now available, moves to develop areas of sub-specialization have begun and an emergency medicine association has been formed. There has been an increase in the diagnostic modalities in the main teaching institution, the University Hospital of the West Indies (UHWI). There is an urgent need for improvements in pre-hospital care. This will require the development of an efficient Emergency Medical Service (EMS). More emphasis and attention is required on disaster medicine, toxicology and trauma. Increased training of emergency physicians and nurses, advances in academia and research, and greater advocacy by local emergency physicians will further advance the specialty.
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Affiliation(s)
- E W Williams
- Emergency Medicine Division, Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Williams-Johnson JA, Hemmings S, Williams EW, Channer G, McDonald AH. Six years experience of angioedema at the University Hospital of the West Indies. W INDIAN MED J 2008; 56:278-81. [PMID: 18072413 DOI: 10.1590/s0043-31442007000300018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Angioedema (AE) is a problem that all doctors inclusive of emergency room physicians and the otolaryngologists are often asked to treat. We present a six-year experience with this disorder. In this series, angiotensin-converting enzyme inhibitors (ACEIs) were related to 60% of admissions for angioedema. Lip and tongue swelling was the most common manifestation. The discontinuation of ACEI therapy and supportive management are the recommended approaches to treatment and prevention of unfavourable outcomes. The authors strongly recommend medic alert bracelets for all patients with this disorder. The use and side effects of ACEI therapy in our population which is predominantly of African descent warrants further investigations.
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Affiliation(s)
- J A Williams-Johnson
- Department of Surgery, Radiology, Anaesthesia and Intensive Care. The University of the West Indies, Kingston 7, Jamaica, West Indies
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Williams EW, Cawich SO, James M, Felix RA, Ashman H, Douglas V, Williams-Johnson J, French S, McDonald AH. Penetrating neck trauma and the aberrant subclavian artery. W INDIAN MED J 2008; 56:288-93. [PMID: 18072416 DOI: 10.1590/s0043-31442007000300021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular injuries from penetrating trauma to the base of the neck are accompanied by significant morbidity and potential mortality. These injuries require several diagnostic adjuncts in order to facilitate early diagnosis and appropriate treatment. Herein reported is the case of a patient who sustained penetrating injury to the thoracic inlet but had a fortuitous anomaly that prevented vascular injury and its attendant complications.
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Affiliation(s)
- E W Williams
- Emergency Medicine Division, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Harding-Goldson HE, Crandon IW, McDonald AH, Augier R, Fearon-Boothe D, Rhoden A, Meeks-Aitken N. Surgical and intensive care needs of head-injured patients transferred to the University Hospital of the West Indies. W INDIAN MED J 2008; 56:230-3. [PMID: 18072402 DOI: 10.1590/s0043-31442007000300007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A cross-sectional, descriptive study utilizing data collected in the 'Trauma Registry' of the Department of Surgery, Radiology, Anaesthesia and Intensive Care at the University Hospital of the West Indies (UHWI) was undertaken to document injury severity, surgical requirements and intensive care needs of head-injured patients transferred to the UHWI over a three-year period Of 144 patients studied, the majority (71%) were young males. Overall, injury tended to be mild Twenty-three patients (16.0%) had severe head injury and 27 patients (18.8%) were admitted to the intensive care unit. Concussion with (33%) or without (36%) skull fracture was the commonest neurological admission diagnosis. Associated non-neurological injuries in 33% were primarily fractures. Fifty-six patients (39%) required surgical intervention. Craniotomies and open reduction and internal fixation of fractures were the commonest procedures. The majority of patients (79.2%) were discharged home; 56 (39%) made a good Glasgow outcome score recovery. Seventeen patients (11.8%) died in hospital. As most of the transferred patients with head injuries in this study had only mild injury, most commonly concussions, and their prognosis was good, we recommend that appropriate educational and training programmes and transfer policies be implemented to minimize inappropriate transfers.
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Affiliation(s)
- H E Harding-Goldson
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Williams EW, Reid M, Lindo JLM, Williams-Johnson J, French S, Singh P, McDonald AH. Association between exposure/non-exposure to the mandatory seat belt law with regards to compliance in vehicle accident victims--a hospital review. W INDIAN MED J 2007; 56:236-9. [PMID: 18072404 DOI: 10.1590/s0043-31442007000300009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Injuries sustained in motor vehicle accidents (MVAs) are a major challenge to the Jamaican healthcare system. In November 1999, Jamaica enacted legislation to make seat belt usage in motor vehicles compulsory. The effect of this policy change on seat belt usage is unclear. This study therefore sought to determine the prevalence of seat belt usage and to determine the association between exposure/non-exposure to the mandatory seat belt law and seat belt use in subjects who presented to the Accident and Emergency Department (A&E) of the University Hospital of the West Indies (UHWI) as a result of motor vehicle accidents. METHODS Subjects were recruited from June to November 2003, post-seat belt law (POBL) period, and May to October 1999, pre-seat belt law (PRBL) period. Data collected included demographic variables, seat belt use and position of the occupants in the vehicle. RESULTS Of the 277 patients who were eligible for inclusion, data were complete in 258 subjects, 87 in the PRBL period and 171 in the POBL period. The prevalence of seat belt use was 47% (PRBL) and 63% (POBL) respectively. There was no significant gender difference at each period. The odds of wearing seat belt in the rear of a motor vehicle were significantly lower than that of a driver (Table 3, OR 0.19, 95% CI 0.07, 0.48). Adjusting for age, gender and position in vehicle exposure, there was about 100% increase in the odds of seat belt use during the post seat belt law era (OR = 2.09, 95% CI 1.21, 3.61). CONCLUSION It is concluded from this hospital-based study that the mandatory seat belt law legislature was associated with increased seat belt use in motor vehicle accident victims. However, current data from the Road Traffic Agency indicate that there is still an alarming number of fatalities. This clearly suggests that additional public health measures are needed to address the epidemic of motor vehicle trauma in Jamaica.
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Affiliation(s)
- E W Williams
- Emergency Medicine Division, Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Crandon IW, Harding-Goldson HE, Benaris M, McDonald AH. Unnecessary admissions of head-injured patients at the University Hospital of the West Indies. W INDIAN MED J 2007; 56:226-9. [DOI: 10.1590/s0043-31442007000300006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Plummer JM, Mitchell DIG, Duncan ND, McDonald AH, Arthurs M. Bile duct injuries in the laparoscopic era: the University Hospital of the West Indies experience. W INDIAN MED J 2007; 55:228-31. [PMID: 17249311 DOI: 10.1590/s0043-31442006000400005] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
During the ten-year period July 1994 to June 2004, 20 patients were seen with iatrogenic bile duct injuries. The case notes of these patients were reviewed. Half of the patients were referred after initial surgery at other hospitals. At the University Hospital of the West Indies, bile duct injury rate was 0.8% and 1% for open and laparoscopic cholecystectomy respectively. Sixty per cent of patients' injuries resulted from open cholecystectomy and the majority of these were during emergency cholecystectomies for acute cholecystitis. A wide range of treatment modalities were employed for patients with minor bile duct injuries but Roux en Y hepaticojejunostomy was the treatment of choice for patients with transection of the common hepatic or bile duct. Follow-up was available in seven of nine patients who had major bile duct injury repair to a median of 36 months and all but one were asymptomatic and had normal liver function tests. There were two deaths because of septic complications.
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Affiliation(s)
- J M Plummer
- Department of Surgery, The University of the West Indies, Kingston 7, Jamaica.
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Plummer JM, Gibson TN, McFarlane MEC, Hanchard B, Martin A, McDonald AH. Clinicopathologic profile of gastric carcinomas at the University Hospital of the West Indies. W INDIAN MED J 2006; 54:364-8. [PMID: 16642652 DOI: 10.1590/s0043-31442005000600004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The objective of this study was to examine the clinicopathologic features of gastric cancer seen at the University Hospital of the West Indies (UHWI) and to compare the findings with other studies. A retrospective study was conducted using data obtained from the surgical pathology reports of all gastrectomies and gastric biopsies during the period January 1993 and December 2002. Additional cases were identified from the Department of Surgery's audit database. Demographic, clinical and pathological features were analyzed. Two hundred and sixteen patients were identified, 126 males and 90 females. One hundred and thirty-six underwent biopsy procedures but no definitive surgery aimed at cancer eradication, while 70 had gastrectomy. The peak age prevalence in both males and females was the 70-79-year age group. While the antrum was the commonest site, there was an overall increase in tumours of the gastro-oesophageal junction and tumours of the entire stomach in the latter five-year period of the review especially in the 50-59-year age group. Epigastric pain and constitutional symptoms were the common presenting features, and the most common gross tumour characteristic was an ulcerating mass, while histologically, the intestinal variety was most common. Lymph node metastases were common. Helicobacter pylori (Hpylori) were present in 16.7% while chronic multifocal atrophic gastritis was present in 40%. This study indicates that the gastric cancer pattern is typical of developing countries. However, the low prevalence of H pylori in the resected specimens may indicate the importance of other risk factors for gastric cancer development in this population. This warrants further study.
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Affiliation(s)
- J M Plummer
- Department of Surgery, The University of the West Indies, Kingston 7, Jamaica.
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Abstract
The use of radiological studies as diagnostic tools in patients with suspected acute appendicitis has increased recently. In this setting, abdominal ultrasonography is viewed as a possible means of avoiding unnecessary surgery. This retrospective study of patients who underwent laparotomy for suspected acute appendicitis was undertaken to determine the sensitivity and specificity of ultrasound in diagnosing acute appendicitis and the frequency of leucocytosis in patients in whom the diagnosis was confirmed by histology. The ultrasound and surgery registers were reviewed to identify 254 referrals for abdominal ultrasound between January 2001 and December 2002 because of a clinical suspicion of acute appendicitis. Of these cases, 223 did not proceed to surgery. The study sample comprised 31 patients who had appendectomies after abdominal ultrasonography. The ultrasound reports, pathological diagnoses and white blood cell counts of these patients were obtained and formed the basis for the analysis. A histological diagnosis was available for 30 cases, in 17 of whom appendicitis was confirmed In these patients, positive ultrasound and leucocytosis were present in five (29%) and nine (53%) respectively. Ultrasound showed 92% specificity and 29% sensitivity for the pre-operative diagnosis of appendicitis. The positive predictive value of ultrasonography (83%) was higher than that of leucocytosis (69%). The sensitivity and specificity of ultrasound and leucocytosis in this study indicate limited utility as preoperative diagnostic tools.
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Affiliation(s)
- W M West
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Williams EW, Ramphal PS, Williams-Johnson J, Ford R, McDonald AH. Spontaneous haemo-pneumothorax: a rare but life-threatening phenomenon. W INDIAN MED J 2006; 54:346-7. [PMID: 16459522 DOI: 10.1590/s0043-31442005000500016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Crandon IW, Harding H, McDonald AH, Bruce CAR, Fearon-Boothe D, Rhoden A, Meeks-Aitken N. Transfer of head-injured patients in Jamaica: is there a problem? W INDIAN MED J 2006; 54:220-4. [PMID: 16312186 DOI: 10.1590/s0043-31442005000400002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Head-injured patients are often transferred to the University Hospital of the West Indies (UHWI) for tertiary care. There is no standardized, agreed protocol governing their transfer. During the three-year period January 1998 to December 2000, 144 head injured patients were transferred to the UHWI from other institutions. They were 70% male, had a mean age of 34 years and spent a mean of 13 days in hospital. Eighteen per cent were admitted to the Intensive Care Unit, where they spent a mean of nine days. On arrival, mean pulse rate was 92 +/- 22 beats/minute, mean systolic blood pressure was 130 +/- 27 mmHg and mean diastolic was 76 +/- 19mmHg. Twenty-eight per cent of patients had a pulse rate above 100/min on arrival and 13.8% had systolic blood pressure below 60 mmHg. The Glasgow Coma Scale score was unrecorded at the referring institution in 70% of cases and by the receiving officers at the UHWI in 23% of cases. Intubation was done on only half of those who were eligible. Junior staff members initiated and carried out transfers whenever this was documented. The types of vehicles and monitoring equipment used could not be determined in most instances. Fifty-eight per cent of patients had minor head injuries, 12%, severe injury and 33%, associated injuries requiring a variety of surgical procedures by multiple specialties. Most patients (80.6%) were discharged home but 11.8% died in hospital. Transfer of head-injured patients, many with multiple injuries is not being performed in a manner consistent with modern medical practice. There is urgent need for implementation of a standardized protocol for the transfer of such patients in Jamaica.
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Affiliation(s)
- I W Crandon
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, Faculty of Medical Sciences, The University of the West Indies, Kingston, Jamaica.
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Plummer JM, Duncan ND, Mitchell DIG, McDonald AH, Reid M, Arthurs M. Laparoscopic cholecystectomy for chronic cholecystitis in Jamaican patients with sickle cell disease: preliminary experience. W INDIAN MED J 2006; 55:22-4. [PMID: 16755815 DOI: 10.1590/s0043-31442006000100006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Laparoscopic cholecystectomy, with its advantages of reduced postoperative pain and shorter hospitalization is the accepted standard of care for patients with symptomatic cholelithiasis. A retrospective study was done to assess the outcome of laparoscopic cholecystectomy in patients with sickle cell disease, a group known for its high postoperative morbidity. The study sample comprised of patients seen at the University Hospital of the West Indies during the period 1999 to 2004. Twelve patients were females and four were males. Their mean age was 28.5 years (range 13-43 years). Fifteen underwent elective cholecystectomy for recurrent episodes of cholecystitis while one patient required an emergency procedure. All patients underwent endoscopic retrograde cholangiopancreatography, which successfully removed common bile duct stones which were present in 25% of the cases. There were four conversions to open cholecystectomy as a result of obscure anatomy due to scarring and adhesions. The duration of surgery ranged from 70-150 minutes. Six patients developed postoperative complications, four of whom had acute chest syndrome. This resulted in death in one patient. The mean postoperative hospitalization period was 5.5 days. This report indicates that patients with sickle cell disease remain a high risk group with the potential for significant morbidity even when subjected to minimal access surgery.
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Affiliation(s)
- J M Plummer
- Department of Surgery, Tropical Metabolism Research Institute, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Williams EW, Williams-Johnson J, French S, Singh P, McDonald AH, Ford R. The effect of hurricane Ivan on emergency department operations at the University Hospital of the West Indies. W INDIAN MED J 2005; 54:232-5. [PMID: 16312188 DOI: 10.1590/s0043-31442005000400004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to determine the impact of Hurricane Ivan on the operations of the Emergency Department (ED) at the University Hospital of the West Indies (UHWI). Hurricane Ivan,--a category four Hurricane--traversed the south coast of the island of Jamaica on September 10, 2004, causing damage to several parishes. The study design is a descriptive retrospective record-based incidence study of all admissions to the ED commencing at 8:00 am September 10, 2004 and ending at 12 midnight September 11, 2004, covering the period of the entire duration of the hurricane as well as immediately after. Injuries that took place during the hurricane, inclusive of gun-shot wounds (GSWs) represented 40% of the total patients seen. The types of admission are listed categorically as well as specific items to be considered in planning for potential disasters of higher magnitude. Overall, the coping mechanism of the ED at UHWI was adequate for this magnitude of disaster.
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Affiliation(s)
- E W Williams
- Accident and Emergency Department, University Hospital of the West Indies, Kingston, Jamaica.
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Williams EW, Chambers D, Ashman H, Williams-Johnson J, Singh P, McDonald AH, Reid M, Brown B. Oesophageal foreign bodies at the University Hospital of the West Indies. W INDIAN MED J 2005; 54:47-50. [PMID: 15892390 DOI: 10.1590/s0043-31442005000100010] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A retrospective study was conducted of 97 patients with oesophageal foreign bodies (EFB). The patients were admitted to assess characteristics of EFB, modes of presentation and radiological and endoscopic findings. The patients were from the University Hospital of the West Indies and most (42%) were over the fourth decade of life. The commonest EFB were bones. A negative radiological finding was not a reliable means to select patients for endoscopy. Oesophagoscopy is a reliable method in the treatment of EFB impaction. There were no major complications or deaths.
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Affiliation(s)
- E W Williams
- Emergency Medicine Division, Department of Surgery, Radiology, Anaesthesia and Intensive Care and Tropical Medicine Research Institute The University Hospital of the West Indies, Kingston 7, Jamaica, West Indies.
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Plummer JM, McDonald AH, McFarlane MEC. Civilian rectal trauma: the surgical challenge. W INDIAN MED J 2004; 53:382-6. [PMID: 15816265] [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: 05/02/2023]
Abstract
Using the Department of Surgery, Radiology, Anaesthesia and Intensive Care's operative database and information from the Trauma Registry for patients presenting after 1998, a retrospective study of patients seen between the period 1992 and 2002 was done at the University Hospital of the West Indies with the objective of determining the treatment and outcome of patients with a diagnosis of rectal trauma. Over the 10-year period, 45 patients were seen with this diagnosis. Eighty-two per cent of the cases were males, with a mean age of 29.8 years (range 16-70 years) while the eight female patients had a mean age of 36.8 years. Low velocity gunshot wounds accounted for 64% of the entire group and for 78% in males. Six of the eight cases seen in females were iatrogenic occurring during gynaecological operations. Sixty-three per cent of rectal injuries were associated with other injuries with the genitourinary system most commonly involved The majority (83%) were diagnosed preoperatively by visualization of the rectal wound or the presence of blood on proctosigmoidoscopy. All the patients had peri-operative antibiotics and diversion with a proximal sigmoid colostomy. Fifteen per cent of cases had presacral drain insertion. Distal rectal washout was not used. There were no deaths. Seventy-three per cent of patients had closure during the period under review at an average time of 8.5 months after initial surgery. The other 27% after an average of 23 months did not have documented closure. The mainstay of treatment for civilian rectal trauma remains diverting sigmoid loop colostomy, despite its morbidity, and peri-operative antibiotics.
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Affiliation(s)
- J M Plummer
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, Section of Surgery, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Williams-Johnson JA, Wilks RJ, McDonald AH. Falls: A modifiable risk factor for the occurrence of hip fractures in the elderly. W INDIAN MED J 2004; 53:238-41. [PMID: 15622677] [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: 05/01/2023]
Abstract
The objective of the study was to examine the clinical and demographic features of patients with hip fractures presenting to the Accident and Emergency Department, the University Hospital of the West Indies (UHWI). The study involved all patients with hip fractures registered in the Trauma Registry at the UHWI between January 1, 1998 and December 31, 2001. They were assessed retrospectively for age, gender, associated extrinsic and intrinsic factors, cause of the fall, location when fracture occurred and the site of the femur that was fractured. One hundred and fifty-two persons were identified There were one hundred and eleven women and forty-one men. Seventy-eight per cent of the falls occurred in the over sixty-five-year age group. Ninety per cent of the patients had a fall associated with their fracture. Most of the falls occurred at the patients' homes. This study indicated that falling at home was the commonest associated factor for the occurrence of hip fractures and preventive measures may lead to reductions in the frequency of hip fractures seen in the emergency room.
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Affiliation(s)
- J A Williams-Johnson
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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26
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Plummer JM, Arthurs M, McDonald AH, Mitchell DIG, McFarlane MEC, West W. Endoscopic retrograde cholangiopancreatography use at the University Hospital of the West Indies. W INDIAN MED J 2004; 53:234-7. [PMID: 15622676] [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: 05/01/2023]
Abstract
All patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) at the University Hospital of the West Indies (UHWI) were entered into a prospective database. Parameters included demographics, indication for the procedure, success of the ERCP and any immediate complications noted. Retrospectively, the patients' case notes were analyzed for complications developing after 24 hours, and outcome. During the period March 1999 to December 2002, a total of 120 consecutive patients were subjected to 123 ERCPs, all being performed by a single gastroenterologist. Of these 120 patients, eight had ERCP as outpatients and were transferred back to their referring hospitals. These patients were excluded from further analysis. Of the 115 UHWI patients, the case notes of 96 were available for analysis and this group formed the basis of this review. ERCP had successful cannulation in 95% of patients. There were 70 females and 26 males with a female to male ratio of 2.7:1. Age ranged from 13 to 85 years (mean +/- SD, 43 +/- 17), males being an average six years older than females. The most common indication for ERCP was a patient with cholelithiasis and abnormal liver function tests scheduled for laparoscopic cholecystectomy. This made up 33% of patients and in this subgroup, sickle cell disease accounted for 50% of cases. Patients with common bile duct stones preoperatively and post-cholecystectomy accounted for 13% and 17% respectively while gallstones pancreatitis accounted for 13% of cases, including three patients with severe pancreatitis. While 64% of the patients had normal cholangiogram, 66% of them had sphincterotomy. Common bile duct stones were seen in 23 cases and complete removal was successful in 48%. There were ten cases (10%) of ERCP pancreatitis and this was severe in three patients and the direct cause of death in one. One patient had ascending cholangitis post ERCP and there were no cases of post-sphincterotomy bleeding or duodenal perforation. Endoscopic retrograde cholangiopancreatography at the UHWI has high diagnostic yield but its therapeutic use needs further development.
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Affiliation(s)
- J M Plummer
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, The University of the West Indies, Kingston 7, Jamaica, West Indies.
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Plummer JM, Gibson TN, Newnham MS, McDonald AH. The management of isolated splenic abscess. W INDIAN MED J 2004; 53:201-2. [PMID: 15352755] [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: 04/30/2023]
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28
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Williams EW, Mansingh A, McDonald AH, Singh P. Bilateral simultaneous rupture of the quadriceps tendon. W INDIAN MED J 2004; 53:139-40. [PMID: 15199729] [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: 04/29/2023]
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McDonald AH. Trauma care in Jamaica. A time for decision. W INDIAN MED J 2002; 51:167-70. [PMID: 12501544] [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: 02/28/2023]
Abstract
The high incidence of trauma in Jamaica is well documented. Trauma accounts for approximately 40 per cent of the workload in both the Accident and Emergency Unit and the surgical wards at the University Hospital of the West Indies. The death rates for motor vehicle accidents and homicide in Jamaica are greater than those in developed countries as well as the rest of the Caribbean region. Many of these deaths occur before the patient reaches hospital. Preventative measures and improved pre-hospital care will reduce these deaths and also lessen the burden injuries place on the health service. In hospitals, most preventable deaths occur within the first few hours of admission. An organized system of care which ensures that the right patient is taken to the right hospital at the right time as well as training in Advanced Trauma Life Support should reduce the preventable death rate. Collaboration is needed between health workers and other concerned groups to stimulate an interest in injury prevention and improvement in trauma care.
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Affiliation(s)
- A H McDonald
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, University of the West Indies, Kingston 7, Jamaica, West Indies.
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Duncan ND, Smith AI, McDonald AH, Mitchell DIG. Biliary surgery in sickle cell disease: the Jamaican experience. J R Coll Surg Edinb 2002; 47:414-7. [PMID: 11878301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Of 62 patients with homozygous sickle cell disease subjected to open cholecystectomy for symptomatic gallstones over a 12-year period at the University Hospital of the West Indies, 25 were males and 37 were females. Of these, 27 were paediatric patients aged 18 years or less, and 35 were adults. Preoperative transfusion was selectively administered. All cases presented with right upper quadrant pain and 15 of 62 with obstructive jaundice. Mucocoele of the gallbladder, empyema of the gallbladder and common bile duct stones were detected in 2, 2, and 23 patients, respectively. Exploration of the common bile duct was necessary in 31 cases and a T-tube sited in 15 cases. Twelve of the 62 patients developed acute chest syndrome post operatively (20%). There were 2 deaths, both occurring in patients who had developed acute chest syndrome; in a 34 year old and a 10 year old patient. Common bile duct related morbidity was proportionately more common in paediatric patients than adults, represented by ductal dilation (48% vs 37%), ductal calculi (44% vs 31%) and retained stones (7% vs 3%).
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Affiliation(s)
- N D Duncan
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, University Hospital of the West Indies, Jamaica
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Newnham MS, Shirley SE, McDonald AH. Granulomatous lobular mastitis. A case report and review of the literature. W INDIAN MED J 2001; 50:236-8. [PMID: 11769035] [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: 02/23/2023]
Abstract
Granulomatous lobular mastitis is a rare, benign, inflammatory breast condition of unknown aetiology that can clinically mimic breast cancer. Awareness of this condition is important, as the appropriate specimens must be taken to confirm the diagnosis and to rule out an infectious aetiology. While surgical excision has been the traditional therapeutic modality, the most appropriate therapy seems to involve the use of corticosteroids, even in the case of recurrence.
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Affiliation(s)
- M S Newnham
- Departments of Surgery, Radiology, Anaesthesia and Intensive Care, and Pathology, University of the West Indies, Mona, Kingston 7, Jamaica
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Mitchell DI, McDonald AH, Williams NP, Royes CA, Duncan ND, Hanchard B. Colonic lipomas at the University Hospital of the West Indies. W INDIAN MED J 2001; 50:144-7. [PMID: 11677913] [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: 02/22/2023]
Abstract
Lipomas of the colon are uncommon but cause diagnostic difficulty when they are symptomatic. The clinical and pathological features of 17 cases of colonic lipomas diagnosed at the University Hospital of the West Indies between 1970 and 1999 are reported. Ten cases were symptomatic, two of these being diagnosed with adult intussusception. Six patients had incidental lipomas in bowel resected for other pathology while one lipoma was diagnosed on sigmoidoscopy. Increased awareness of these lesions will enhance pre-operative diagnostic accuracy.
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Affiliation(s)
- D I Mitchell
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, Department of Pathology, University of the West Indies, Kingston 7, Jamaica.
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Abstract
Twenty-seven children aged 18 years and under with homozygous sickle-cell disease had open cholecystectomy for symptomatic gallstones over the 12-year period 1985-1997. Emergency procedures (done during period of acute exacerbation of symptoms) were performed on 16 patients. Four with haemoglobin levels greater than 1 g/dl below their steady state received a simple blood transfusion preoperatively designed to raise haemoglobin levels to 10 g/dl. All had acute or acute on chronic cholecystitis based on histological examination of gallbladder specimens. Twelve had common bile duct stones. In two patients calculi were missed intraoperatively but these subsequently passed into the duodenum after a period saline irrigation via an in-situ t-tube. Six developed the acute chest syndrome (aetiology not determined) and this progressed to multi system failure and death in one. This high level of postoperative mobility and mortality may in part be due to the high proportion of emergency procedures.
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Affiliation(s)
- N D Duncan
- Department of Surgery, Radiology, Anaesthesia and Intensive Care, University Hospital of the West Indies, Kingston 7, Jamaica.
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Abstract
BACKGROUND Ring avulsion injuries can vary in severity from mere breach of the skin through to complete amputation or degloving. Management of the more severe injuries remains controversial in deciding whether to salvage or amputate. METHOD Six cases managed between 1991 and 1997 are presented. RESULTS Results were comparable to the larger series published. CONCLUSION Referral to a microsurgical unit and attempted repair where possible are recommended.
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McDonald AH, Weir K, Schneider M, Gudenkauf L, Sanger JR. Silicone gel enhances the development of autoimmune disease in New Zealand black mice but fails to induce it in BALB/cAnPt mice. Clin Immunol Immunopathol 1998; 87:248-55. [PMID: 9646834 DOI: 10.1006/clin.1998.4532] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Anecdotal evidence links silicone gel breast implants with the development of autoimmune connective tissue disease in women. To investigate whether silicone gel is capable of directly inducing and/or enhancing the development of autoimmune disease, female BALB/cAnPt (BALB/c) and New Zealand Black (NZB) mice were injected subcutaneously with silicone gel, pristane, a nonmetabolizable substance that can cause plasmacytomas in BALB/c and NZB mice, or saline and monitored for the development of glomerulonephritis and autoantibody production. NZB, but not BALB/c, mice spontaneously develop autoantibodies and an autoimmune hemolytic anemia by 12 months of age. Over a period of 10 months, biweekly screening for proteinuria revealed increases in urinary protein in NZB mice that received multiple injections of either silicone gel or pristane. In contrast, urinary protein was unaffected in identically treated BALB/c mice. Although, silicone gel had no effect on serum titers of antierythrocyte antibodies in NZB mice, the hematocrits were significantly decreased. Moreover, silicone gel both increased the concentration of IgM anti-type I collagen antibodies and skewed the immunofluorescent staining pattern of serum autoantibodies on HEp-2 cells. In contrast, silicone gel failed to induce the production of anti-erythrocyte or antinuclear antibodies in BALB/c mice and induced only slight increases in IgG anti-type I collagen antibodies. These results suggest that silicone gel can exacerbate the development of autoimmune disease in autoimmune NZB mice, but fails to induce disease in normal BALB/c mice. This is consistent with several epidemiological studies failing to demonstrate an increase in the incidence of autoimmune disease in women with breast implants. However, because silicone gel was able to exacerbate autoimmune disease in NZB mice, it may play a similar role in the development of autoimmune disease in a small percentage of women who are genetically susceptible to such diseases.
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Affiliation(s)
- A H McDonald
- Department of Pathology, Medical College of Wisconsin, Milwaukee, USA
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McDonald AH, Byrd LG, Mainhart CR, Sopher J, Smith-Gill SJ. Plasmacytoma-refractory BALB/cAnPt mice have naive T cell and highly specific B cell responses to antigen. Mol Immunol 1996; 33:1183-96. [PMID: 9070667 DOI: 10.1016/s0161-5890(96)00103-4] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Recently, a reduction in the incidence of pristane-induced plasmacytomas in BALB/cAnPt (BALB/c) mice that were kept in viral specific pathogen-free (SPF) conditions has been reported. Environmentally, these SPF-BALB/c mice differed from conventionally-housed (CON) mice only in viral exposure and diet (i.e. sterilization of mouse chow), since microbial colonization of the intestinal tract was seen to be equivalent. This report assessed the ability of SPF- and CON-BALB/c mice to respond to immunologic challenge with soluble antigen, i.e. hen egg white lyzosyme (HEL), as a means of evaluating differences in T and B cell function and, indirectly, evaluating the possible effects these differences might have on plasmacytoma development. When cultured in vitro for 5 days with HEL, HEL-primed lymph node cells (LNC) from SPF-BALB/c mice proliferated to a significantly lesser extent than HEL-primed CON-BALB/c LNC. Moreover, HEL-induced production of IFN-gamma and IL-5 was significantly lower in SPF LNC. Serum IgG1 levels were 10-fold lower in SPF-BALB/c mice with, or without prior immunization with HEL and were not reconstituted by repeated injections of HEL in adjuvant. Serum IgM levels of SPF- and CON-BALB/c mice were equivalent. This reduction in immune responses could not be attributed to a lack of colonization of secondary lymphoid organs, since flow cytometric analysis of LNC revealed no difference in the number of recoverable cells and the proportion of lymphocyte subsets (CD4+, CD8+ and CD45+ cells) obtained from SPF- and CON-BALB/c mice. However, only CON LNC were induced to increase surface expression of CD44 after antigenic or mitogenic stimulation in vitro. Antibody responsiveness to HEL, as evidenced by serum anti-HEL binding or splenic hybridoma studies, demonstrated higher levels of IgG1 antibodies in CON BALB/c mice than in SPF mice. However, a greater proportion of the SPF IgG1 antibodies present were specifically directed against HEL, so that specific activity was greater in SPF-BALB/c mice. Therefore, while SPF BALB/c mice have a more restricted response to HEL than CON-BALB/c mice, those antibodies that are produced are more specifically directed against HEL with very little apparent bystander/polyclonal activation of multireactive cells. Resistance to plasmacytomas in SPF-BALB/c mice, therefore, may stem from a reduced number of circulating memory T and B cells, which are capable of reacting and/or crossreacting with a chronic inflammatory stimulus.
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Affiliation(s)
- A H McDonald
- Department of Pathology, Medical College of Wisconsin, Milwaukee 53226, U.S.A
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37
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Affiliation(s)
- A H McDonald
- Department of Pathology, Medical College of Wisconsin, Milwaukee, USA
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McDonald AH, van den Berg EH. Effect of watering regimen on injury to corn and grain sorghum by pratylenchus species. J Nematol 1993; 25:654-658. [PMID: 19279822 PMCID: PMC2619429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
The effect of simulated rainfall frequency on the pathogenicity of Pratylenchus zeae and P. brachyurus was studied in four greenhouse experiments. Corn and grain sorghum were watered at different intervals during predetermined cycles to create a gradient of water-stressed plants. Each experiment included nematode and uninoculated treatments. Growth reaction of plants to different frequencies of watering was significant but was not affected by the presence of nematodes. Pratylenchus zeae numbers differed among watering regimens on corn but not on sorghum. Numbers of P. brachyurus did not differ among watering regimens on corn or sorghum. Both lesion nematode species were harmful to corn, but sorghum increased plant growth in response to P. brachyurus. It is concluded that water stress is not the only environmental factor that influences the pathogenicity of these two species on corn and sorghum.
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McDonald AH, Degrassi A. Pristane induces an indomethacin inhibitable inflammatory influx of CD4+ T cells and IFN-gamma production in plasmacytoma-susceptible BALB/cAnPt mice. Cell Immunol 1993; 146:157-70. [PMID: 8425224 DOI: 10.1006/cimm.1993.1014] [Citation(s) in RCA: 14] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In BALB/cAnPt (BALB/c) mice, the intraperitoneal injection of pristane induces the formation of chronic oil granulomatous tissue and a high incidence of plasmacytomas (PCT). DBA/2N (DBA) and (BALB/c x DBA)F1 hybrid (CDF1) mice develop oil granulomas but no PCT. Recent studies comparing pristane-injected conventionally housed BALB/c mice with specific pathogen-free BALB/c mice (SPF) demonstrated a significant reduction in both the incidence of PCT and the T cell infiltration of oil granulomatous tissue in SPF mice. In this study, FACS analysis was performed to determine the proportion of myeloid, T. and B cells present in pristane-induced peritoneal exudate (PE), and oil granulomas (OG) of BALB/c, DBA, and CDF1 mice. At all time points studied, the majority of cells recovered from the PE and OG of all three strains of mice were Mac-1+, presumably macrophages and neutrophils. Neither Ly-5(B220)+ B cells nor CD8+ T cells were significantly altered by pristane injection. BALB/c mice had a dramatic influx of CD4+ T lymphocytes (three- to fivefold) more than 50 days after the initial injection of pristane. The PCT-resistant DBA and CDF1 mice did not. This increase in CD4+ cells in BALB/c mice was not significantly affected by a second injection of pristane nor was it induced by a second injection in DBA mice. Indomethacin, which has been shown to prevent the development of PCT in BALB/c mice, prevented the infiltration of CD4+ T cells. In addition, pristane-induced levels of interferon-gamma greater than controls were found in the peritoneal lavages of BALB/c mice at all time points tested but not in DBA or indomethacin-treated BALB/c mice. In contrast, pristane injection increased levels of interleukin-5 in DBA but not BALB/c mice.
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Affiliation(s)
- A H McDonald
- Laboratory of Genetics, National Cancer Institute/National Institutes of Health, Bethesda, Maryland 20892
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Byrd LG, McDonald AH, Gold LG, Potter M. Specific pathogen-free BALB/cAn mice are refractory to plasmacytoma induction by pristane. J Immunol 1991; 147:3632-7. [PMID: 1682379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Forty to sixty percent of conventionally (CON) raised BALB/cAnPt (BALB/c) mice develop plasmacytomas (PCT) when injected with three 0.5 ml i.p. injections of pristane. When CON-BALB/c mice were converted to specific pathogen free (SPF) status by foster nursing caesarean delivered term mice on C3H/HeN SPF mothers and maintained under strict SPF conditions, less than 5% of the mice developed pristane-induced PCT. FACS analysis of the cellular composition of oil granulomatous tissue revealed a dramatic influx of CD4+ cells in CON mice that was significantly reduced in SPF mice. Moreover, while both CON and SPF mice had similar patterns of gut flora colonization, only CON-BALB/c mice had occasional circulating antibodies to mouse hepatitis virus and Sendai viruses. Maintenance in strict SPF conditions, therefore, results in a prolonged state of relative Ag deprivation and a failure to continuously activate new T and B cell populations. The results suggest that PCT formation depends on exogenous antigenic stimulation and that the presence of minimal gut flora is insufficient to render these mice susceptible to PCT induction.
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Affiliation(s)
- L G Byrd
- Laboratory of Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Byrd LG, McDonald AH, Gold LG, Potter M. Specific pathogen-free BALB/cAn mice are refractory to plasmacytoma induction by pristane. The Journal of Immunology 1991. [DOI: 10.4049/jimmunol.147.10.3632] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Forty to sixty percent of conventionally (CON) raised BALB/cAnPt (BALB/c) mice develop plasmacytomas (PCT) when injected with three 0.5 ml i.p. injections of pristane. When CON-BALB/c mice were converted to specific pathogen free (SPF) status by foster nursing caesarean delivered term mice on C3H/HeN SPF mothers and maintained under strict SPF conditions, less than 5% of the mice developed pristane-induced PCT. FACS analysis of the cellular composition of oil granulomatous tissue revealed a dramatic influx of CD4+ cells in CON mice that was significantly reduced in SPF mice. Moreover, while both CON and SPF mice had similar patterns of gut flora colonization, only CON-BALB/c mice had occasional circulating antibodies to mouse hepatitis virus and Sendai viruses. Maintenance in strict SPF conditions, therefore, results in a prolonged state of relative Ag deprivation and a failure to continuously activate new T and B cell populations. The results suggest that PCT formation depends on exogenous antigenic stimulation and that the presence of minimal gut flora is insufficient to render these mice susceptible to PCT induction.
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Affiliation(s)
- L G Byrd
- Laboratory of Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - A H McDonald
- Laboratory of Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - L G Gold
- Laboratory of Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - M Potter
- Laboratory of Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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McDonald AH, Fletcher PR. Ruptured rectal prolapse. W INDIAN MED J 1990; 39:190-2. [PMID: 2264336] [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: 12/31/2022]
Abstract
Rectal prolapse is not a common surgical disorder. The complication reported here, of evisceration of small bowel through a prolapsed rectum, is extremely rare and is the first case reported in the West Indies. Some of the features of rectal prolapse are described, and the surgical management of this particular complication is discussed.
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McDonald AH, Hanchard B, Shah D, Fletcher PR, DuQuesnay R. Fine needle aspiration biopsy in the diagnosis of breast cancer. W INDIAN MED J 1990; 39:71-3. [PMID: 2205978] [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: 12/30/2022]
Abstract
A prospective study of 176 Fine Needle Aspiration Biopsies (FNAB) in 172 patients was carried out to assess the accuracy of FNAB in diagnosing breast cancer at the University Hospital of the West Indies. The results showed 99 per cent and 97 per cent accuracy and sensitivity rates, respectively. There were no false positives and a one per cent false negative rate. FNAB provides a rapid, safe and cheap method of accurately diagnosing breast cancer.
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McDonald AH, Swanborg RH. Antigen-specific inhibition of immune interferon production by suppressor cells of autoimmune encephalomyelitis. The Journal of Immunology 1988. [DOI: 10.4049/jimmunol.140.4.1132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Previous work from this laboratory has revealed that spleen and/or lymph node cells from Lewis rats, that have recovered from an acute episode of experimental autoimmune encephalomyelitis (EAE), suppress the development of EAE when injected into syngeneic recipients subsequently challenged with myelin basic protein (MBP) in CFA. In an effort to understand the mechanism of this suppression, we measured the production of immune IFN-gamma, which may be required for the induction of an immune response, by EAE effector T cells (which transfer disease) and EAE suppressor cells when cultured in vitro with MBP. We now report that EAE effector T cells produce IFN-gamma when cultured in vitro with MBP. In contrast, spleen cells from recovered rats (which manifest suppressor activity in vivo) do not produce IFN-gamma. Moreover, in cell mixing experiments, these suppressor spleen cells inhibited the production of IFN-gamma by EAE effector cells. This inhibition was not eliminated by the removal of macrophages nor by the inhibition of PG synthesis by indomethacin. Furthermore, the inhibition was shown to be Ag-specific and mediated by nylon-adherent, radiation-sensitive splenic T cells. The findings suggest that suppressor cells regulate EAE by inhibiting IFN-gamma production by effector cells. This inhibition may result in the down-regulation of IFN-gamma-induced expression of class II major histocompatibility Ag on cells of the central nervous system, thus reducing the presentation of tissue-specific Ag (i.e., MBP) to autoreactive lymphocytes.
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Affiliation(s)
- A H McDonald
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
| | - R H Swanborg
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
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McDonald AH, Swanborg RH. Antigen-specific inhibition of immune interferon production by suppressor cells of autoimmune encephalomyelitis. J Immunol 1988; 140:1132-8. [PMID: 2963860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Previous work from this laboratory has revealed that spleen and/or lymph node cells from Lewis rats, that have recovered from an acute episode of experimental autoimmune encephalomyelitis (EAE), suppress the development of EAE when injected into syngeneic recipients subsequently challenged with myelin basic protein (MBP) in CFA. In an effort to understand the mechanism of this suppression, we measured the production of immune IFN-gamma, which may be required for the induction of an immune response, by EAE effector T cells (which transfer disease) and EAE suppressor cells when cultured in vitro with MBP. We now report that EAE effector T cells produce IFN-gamma when cultured in vitro with MBP. In contrast, spleen cells from recovered rats (which manifest suppressor activity in vivo) do not produce IFN-gamma. Moreover, in cell mixing experiments, these suppressor spleen cells inhibited the production of IFN-gamma by EAE effector cells. This inhibition was not eliminated by the removal of macrophages nor by the inhibition of PG synthesis by indomethacin. Furthermore, the inhibition was shown to be Ag-specific and mediated by nylon-adherent, radiation-sensitive splenic T cells. The findings suggest that suppressor cells regulate EAE by inhibiting IFN-gamma production by effector cells. This inhibition may result in the down-regulation of IFN-gamma-induced expression of class II major histocompatibility Ag on cells of the central nervous system, thus reducing the presentation of tissue-specific Ag (i.e., MBP) to autoreactive lymphocytes.
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Affiliation(s)
- A H McDonald
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
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Kitney RI, Fulton T, McDonald AH, Linkens DA. Transient interactions between blood pressure, respiration and heart rate in man. J Biomed Eng 1985; 7:217-24. [PMID: 4033097 DOI: 10.1016/0141-5425(85)90022-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Auto regressive spectral estimation techniques have been used to follow transient interactions between mean blood pressure, respiration and heart rate. This demonstrates that these inter-relationships are variable. It is concluded that while central modulation of heart rate is the major factor in the interactions, when the heart rate is fixed, peripheral modulation of the blood pressure by respiration is clearly demonstrated.
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McDonald AH, Kitney R, Damper R. The distribution of energy in the electrocardiogram. Clin Sci (Lond) 1973; 45:4P-5P. [PMID: 4719181 DOI: 10.1042/cs045004pa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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