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Amin K, Fahad Ullah M, Hannon E, Feaney G, Khan J. 950 A Close Loop Audit to Assess Awareness Among Non-Consultant Hospital Doctors Re Use of Personal Protective Equipment. Br J Surg 2021. [PMCID: PMC8524480 DOI: 10.1093/bjs/znab259.759] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Introduction Personal protective equipments (PPEs) are like war uniforms in the fight against Corona Pandemic. The limited supply of PPEs warrant their proper use not only to avoid shortage of supplies but also to prevent any infectious spread to healthcare workers. This study aimed at analyzing awareness among non-consultant hospital doctors re proper use of PPEs Method A questionnaire was devised using local available guidelines published by university Hospital Limerick. The study was done in 2 phases. In 1st phase 100 questionnaires were distributed to non-consultant hospital doctors(NCHDs). Results were analysed and after 1st phase and emails were sent with results and local guidelines and a zoom educational session was organized. In 2nd phase, questionnaire was redistributed in a week's time and results were re analysed to close the loop. Results 200 NCHDs participated in the study,100 in each phase. Most common age group in two phases was 21-30 yrs. Awareness about PPEs use for Covid 19 increased significantly in 2nd phase across all domains (what is included in PPEs (100% from 91%), Sequence for putting on PPEs (52% to 88% p < 0.05), steps for FIT test (57% to 74% p = 0.247) and sequence for removing PPEs (47% to 81% p < 0.05). Conclusions Though PPEs donning and doffing sessions were organized by the hospital officially, Awareness about effective use of PPEs among NCHDs further improved after organizing a Zoom educational session and auditing.
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Affiliation(s)
- K Amin
- University Hospital Limerick, Limerick, Ireland
| | | | - E Hannon
- University Hospital Limerick, Limerick, Ireland
| | - G Feaney
- University Hospital Limerick, Limerick, Ireland
| | - J Khan
- University Hospital Limerick, Limerick, Ireland
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Hannon E, Leonard A, Martin L, Lyons M, Deasy C, Gallagher PF, Brosnan S, Ahern E, James K. Letter to the Editor: An Unknown Unknown: Early Identification of Dysphagia in Frail Patients in the Emergency Department. J Nutr Health Aging 2021; 25:1030-1031. [PMID: 34545925 DOI: 10.1007/s12603-021-1653-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- E Hannon
- Evelyn Hannon, Specialist Registrar in Geriatric Medicine, Department of Geriatric Medicine, Cork University Hospital, Cork, Ireland, Phone: 00353 861943693, /, Twitter handle: @EvelynHannon
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Charnell AM, Hannon E, Burke D, Iredale MR, Sutcliffe JR. Virtual consultations: delivering outpatient clinics in paediatric surgery during the COVID-19 pandemic. Ann Pediatr Surg 2020; 16:49. [PMID: 34899879 PMCID: PMC7700816 DOI: 10.1186/s43159-020-00060-w] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/10/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The COVID-19 pandemic has resulted in many changes to clinical practice, including the introduction of remote clinics. Those familiar with remote clinics have reported benefits to their use, such as patient satisfaction and cost benefits; however, ongoing challenges exist, including delivering optimal patient-centred care. As a tertiary paediatric surgery unit in the UK, completing remote clinics was a new experience for most of our surgical team. We completed a service evaluation early into the COVID-19 pandemic aiming to define and address issues when delivering remote clinics in paediatric surgery. Remote clinics were observed (telephone and video), with follow-up calls to families following the consultations. RESULTS Eight paediatric surgeons were observed during their remote clinics (telephone n = 6, video n = 2). Surgeons new to remote clinics felt their consultations took longer and were reluctant to discharge patients. The calls did not always occur at the appointed time, causing some upset by parents. Prescription provision and outpatient investigations led to some uncertainty within the surgical team. Families (n = 11) were called following their child's appointment to determine how our remote clinics could be optimised. The parents all liked remote clinics, either as an intermediate until a face-to-face consultation or for continued care if appropriate.Our findings, combined by discussions with relevant managers and departments, led to the introduction of recommendations for the surgical team. An information sheet was introduced for the families attending remote clinics, which encouraged them to take notes before and during their consultations. CONCLUSIONS There must be strong support from management and appropriate departments for successful integration of remote clinics. Surgical trainees and their training should be considered when implementing remote clinics. Our learning from the pandemic may support those considering integrating remote clinics in the future.
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Affiliation(s)
- A. M. Charnell
- Department of Paediatric Surgery, Leeds Children’s Hospital NHS Trust, Leeds, UK
- Leeds Institute of Medical Education, University of Leeds, Leeds, LS2 9JT UK
| | - E. Hannon
- Department of Paediatric Surgery, Leeds Children’s Hospital NHS Trust, Leeds, UK
| | - D. Burke
- Department of Paediatric Surgery, Leeds Children’s Hospital NHS Trust, Leeds, UK
- Leeds Institute of Medical Education, University of Leeds, Leeds, LS2 9JT UK
| | - M. R. Iredale
- Department of Paediatric Surgery, Leeds Children’s Hospital NHS Trust, Leeds, UK
| | - J. R. Sutcliffe
- Department of Paediatric Surgery, Leeds Children’s Hospital NHS Trust, Leeds, UK
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Thakkar HS, Hewitt R, Cross K, Hannon E, De Bie F, Blackburn S, Eaton S, McLaren CA, Roebuck DJ, Elliott MJ, Curry JI, Muthialu N, De Coppi P. The multi-disciplinary management of complex congenital and acquired tracheo-oesophageal fistulae. Pediatr Surg Int 2019; 35:97-105. [PMID: 30392126 PMCID: PMC6325990 DOI: 10.1007/s00383-018-4380-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/18/2018] [Indexed: 12/02/2022]
Abstract
AIM OF THE STUDY Complex tracheo-oesophageal fistulae (TOF) are rare congenital or acquired conditions in children. We discuss here a multidisciplinary (MDT) approach adopted over the past 5 years. METHODS We retrospectively collected data on all patients with recurrent or acquired TOF managed at a single institution. All cases were investigated with neck and thorax CT scan. Other investigations included flexible bronchoscopy and bronchogram (B&B), microlaryngobronchoscopy (MLB) and oesophagoscopy. All cases were subsequently discussed in an MDT meeting on an emergent basis if necessary. MAIN RESULTS 14 patients were referred during this study period of which half had a congenital aetiology and the other half were acquired. The latter included button battery ingestions (5/7) and iatrogenic injuries during oesophageal atresia (OA) repair. Surgical repair was performed on cardiac bypass in 3/7 cases of recurrent congenital fistulae and all cases of acquired fistulae. Post-operatively, 9/14 (64%) patients suffered complications including anastomotic leak (1), bilateral vocal cord paresis (1), further recurrence (1), and mortality (1). Ten patients continue to receive surgical input encompassing tracheal/oesophageal stents and dilatations. CONCLUSIONS MDT approach to complex cases is becoming increasingly common across all specialties and is important in making decisions in these difficult cases. The benefits include shared experience of rare cases and full access to multidisciplinary expertise.
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Affiliation(s)
- H. S. Thakkar
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK
| | - R. Hewitt
- Department of Otolaryngology, Great Ormond Street Hospital, London, UK ,Tracheal Team, Great Ormond Street Hospital, London, UK
| | - K. Cross
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK
| | - E. Hannon
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK
| | - F. De Bie
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK ,General Surgery Resident, KU Leuven, Leuven, Belgium
| | - S. Blackburn
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK
| | - S. Eaton
- Stem Cells and Regenerative Medicine Section, DBC, University College London, London, UK ,Department of Radiology, Great Ormond Street Children’s Hospital, London, UK
| | - C. A. McLaren
- Tracheal Team, Great Ormond Street Hospital, London, UK ,Stem Cells and Regenerative Medicine Section, DBC, University College London, London, UK ,Department of Radiology, Great Ormond Street Children’s Hospital, London, UK
| | - D. J. Roebuck
- Tracheal Team, Great Ormond Street Hospital, London, UK ,Stem Cells and Regenerative Medicine Section, DBC, University College London, London, UK ,Department of Radiology, Great Ormond Street Children’s Hospital, London, UK
| | - M. J. Elliott
- Tracheal Team, Great Ormond Street Hospital, London, UK ,Department of Cardiothoracic Surgery, Great Ormond Street Hospital, London, UK
| | - J. I. Curry
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK
| | - N. Muthialu
- Tracheal Team, Great Ormond Street Hospital, London, UK ,Department of Cardiothoracic Surgery, Great Ormond Street Hospital, London, UK
| | - P. De Coppi
- Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK ,Tracheal Team, Great Ormond Street Hospital, London, UK ,Stem Cells and Regenerative Medicine Section, DBC, University College London, London, UK
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Urbani L, Camilli C, Crowley C, Phylactopoulos D, Natarajan D, Scottoni F, Pellegata A, McCann C, Urciuolo A, Baradez M, Hannon E, Deguchi K, Gjinovci A, Cossu G, Eaton S, Bonfanti P, De Coppi P. Development of a bioartificial oesophagus engineered with primary mesoangioblasts, neural and epithelial cells for preclinical studies. Cytotherapy 2017. [DOI: 10.1016/j.jcyt.2017.02.034] [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: 11/29/2022]
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Day T, Sylvan A, Christoforides S, Hannon E, Curry J, Fenton M, Burch M, Simmonds J. Pancreatitis Following Paediatric Heart Transplantation. J Heart Lung Transplant 2017. [DOI: 10.1016/j.healun.2017.01.730] [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: 10/19/2022] Open
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7
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Pishva E, Kenis G, Hannon E, Viechtbauer W, Jeffries A, Lardenoije R, Sienaert P, van Os J, Stek M, Rutten B. Genome-wide meta-analysis of DNA methylation changes associated with antidepressant effects of Electroconvulsive Therapy. Brain Stimul 2017. [DOI: 10.1016/j.brs.2017.01.146] [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: 11/17/2022] Open
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Spiers H, Bray N, Hannon E, Schalkwyk L, Wong C, Pidsley R, Smith R, Mill J. ISDN2014_0171: Dynamic and sex‐specific changes in DNA methylation during human fetal brain development. Int J Dev Neurosci 2015. [DOI: 10.1016/j.ijdevneu.2015.04.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Affiliation(s)
| | | | | | | | | | | | | | - J. Mill
- King's College LondonUK
- Exeter UniversityUK
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Hannon E, Williams R, Allen R, Okoye B. Re: UK intussusception audit: A national survey of practice and audit of reduction rates. A reply. Clin Radiol 2014; 69:e433. [DOI: 10.1016/j.crad.2014.05.007] [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] [Received: 05/08/2014] [Accepted: 05/13/2014] [Indexed: 10/25/2022]
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Hannon E, O'Shaughnessy M, Clover AJP. Does upgraded histological grade account for increase in recurrence rates? RE: Re-excision of incompletely excised cutaneous squamous cell carcinoma: histological findings influence prognosis. J Plast Reconstr Aesthet Surg 2013; 66:874-5. [PMID: 23419682 DOI: 10.1016/j.bjps.2013.01.022] [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] [Received: 01/15/2013] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
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Manasia A, Kang H, Hannon E, Lu Y, Oropello J, Leibowitz A, Stein J, Benjamin E. Effects of the stable prostacyclin analogue iloprost on mesenteric blood flow in porcine endotoxic shock. Crit Care Med 1997; 25:1222-7. [PMID: 9233751 DOI: 10.1097/00003246-199707000-00026] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To determine the effects of the stable prostacyclin analog, iloprost, in a porcine model of endotoxin-induced mesenteric ischemia. DESIGN Prospective, experimental, randomized, controlled study. SETTING Animal research laboratory at a university medical center. INTERVENTIONS Pigs were randomized to receive a constant infusion of iloprost (0.18 microg/kg/min) or an equivalent amount of carrier solution (normal saline) 30 mins before being infused with endotoxin (100 microg/kg over 1 hr). The infusion with iloprost or carrier solution was continued for the duration of the experiment. MEASUREMENTS AND MAIN RESULTS Twelve pigs (six per group), weighing between 20 and 22 kg, underwent laparotomy during which a magnetic flowprobe was placed around the superior mesenteric artery and an ileal tonometer was inserted. Thirty minutes before they were infused with endotoxin, the animals were randomized to receive intravenous iloprost or normal saline. Endotoxin was infused centrally over a 60-min period. Animals received normal saline at a rate of 1.2 mL/kg/min which was begun at the start of the endotoxin infusion. Data were measured at the end of the endotoxin infusion (E60) and 1 hr later (E120). Mean arterial pressure was not affected by the dosage of iloprost used in this experiment. After resuscitation, the cardiac output returned to baseline in the iloprost-treated group but remained decreased in the control group (2.6 +/- 0.5 vs. 1.6 +/- 0.4 L/min). Superior mesenteric blood flow increased 34% above baseline levels in animals pretreated with iloprost (from 363 +/- 85 to 485 +/- 81 mL/min). The superior mesenteric PCO2 was significantly higher (53 +/- 9 vs. 40 +/- 5 torr; 7.1 +/- 1.2 vs. 5.3 +/- 0.7 kPa) and the ileal intramucosal pH was significantly lower (7.07 +/- .28 vs. 7.44 +/- .23) in the control group than in the iloprost-treated group. CONCLUSIONS Pretreatment with intravenous iloprost effectively increased intestinal blood flow in this model of endotoxin-induced mesenteric ischemia. This action of the drug resulted in an attenuation of ileal intracellular acidosis. Since low-dose iloprost had no effect on mean arterial pressure, it may be a useful adjunct in the treatment of sepsis and septic shock.
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Affiliation(s)
- A Manasia
- Department of Surgery, Mount Sinai Medical Center, City University of New York, New York 10029, USA
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12
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Nierman DM, Eisen DI, Fein ED, Hannon E, Mechanick JI, Benjamin E. Transthoracic bioimpedance can measure extravascular lung water in acute lung injury. J Surg Res 1996; 65:101-8. [PMID: 8903454 DOI: 10.1006/jsre.1996.0350] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We used a porcine endotoxemic model of acute lung injury to compare extravascular lung water (EVLW) measured by right transthoracic bioimpedance to postmortem gravimetric EVLW measurements. Adult pigs were randomized into control (N = 5) or endotoxin groups [150 microgram/kg Escherichia coli lipopolysaccharide B for 1 hr followed by 3 hr of resuscitation for a thermodilution cardiac output less than 90% of baseline using either isotonic saline (N = 5) or isooncotic albumin (N = 5)]. Right lung resistance was measured using a novel electrode array and a highly sensitive analyzer and was used to calculate right lung resistivity. At the end of the experiment, animals in the endotoxin-albumin group had higher gravimetric EVLWs than those in the endotoxin-saline or control groups (P < 0.05). Right lung resistivity corrected for body weight significantly correlated with gravimetric EVLW (r2 = 0.49; SEE = 0.96; P = 0.0038). Using multiple regression analysis, a predictive equation for EVLW based on right lung resistivity, body weight, and mean pulmonary artery pressure was generated (r2 = 0.81; SEE = 0.60; P < 0.0001). These results demonstrate that right lung resistivity measurements can provide a noninvasive estimate of EVLW. In addition, crystalloid may be preferable to colloid for fluid resuscitation in noncardiogenic pulmonary edema.
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Affiliation(s)
- D M Nierman
- Department of Medicine, The Mount Sinai Medical Center, New York, New York 10029-6574, USA
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Abstract
STUDY OBJECTIVE To compare the performance of continuous fiberoptic blood gas monitoring with standard, intermittent blood gas sampling in the measurement of arterial and central venous blood gases during marked hemodynamic changes. DESIGN Prospective, consecutive, enrollment, experimental study. SETTING Research laboratory at a university medical center. PARTICIPANTS Seven anesthetized, mechanically ventilated pigs. INTERVENTIONS Severe shock was induced by hemorrhage in pigs monitored by a pulmonary artery catheter, an arterial line, and two fiberoptic blood gas sensors: one intra-arterial, and the other inserted into the superior vena cava via right internal jugular vein cutdown. Fiberoptic blood gas monitor measurements were compared with standard intermittent blood gas sampling. MEASUREMENTS AND RESULTS A total of 184 blood gas samples were compared in seven animals at baseline, during shock, and after resuscitation. The baseline mean (+/- 1 SD) cardiac output decreased from 4.0 +/- 0.9 to 1.2 +/- 0.6 L/min during shock and returned to baseline after retransfusion (3.9 +/- 1.3 L/min). The comparison of continuous fiberoptic blood gas monitoring with intermittent blood gas sampling showed a bias+/-precision of 0.035 +/- 0.047 for arterial pH, 0.021 +/- 0.031 for central venous pH, -4.09 +/- 2.96 mm Hg (-0.55 +/- 0.39 kPa) for arterial Pco2, -3.67 +/- 2.44 mm Hg (-0.49 +/- 0.3 3 kPa) for central venous Pco2, -5.79 +/- 9.64 mm Hg (-0.77 +/- 1.29 kPa) for arterial Po2, and -7.85 +/- 8.52 mm Hg (-1.05 +/- 1.14 kPa) for central venous Po2. CONCLUSIONS Continuous fiberoptic blood gas monitoring agrees closely with standard intermittent blood gas sampling during severe hemodynamic shifts and has a comparable accuracy for both arterial and venous blood gas measurements. Changes in venous Pco2 have recently been shown to correlate with changes in global tissue perfusion (eg, changes in cardiac output). Such data, available immediately via continuous venous blood gas monitoring, may be useful for monitoring shock and the response to resuscitation.
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Affiliation(s)
- J M Oropello
- Department of Surgery, Mount Sinai Medical Center, New York, USA
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Ezeugwu C, Hannon E, Savel T, Kreisel D, Manasia A, Nfonoyim J, Oropello JM, Benjamin E. THE EFFECTS OF BLOCKING CALCITONIN GENE RELATED PEPTIDE, and NITRIC OXIDE SYNTHASE IN A RAT MODEL OF ENDOTOXIC SHOCK. Shock 1995. [DOI: 10.1097/00024382-199506000-00174] [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: 11/25/2022]
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Manasia A, Hannon E, Oropello J, Leibowitz A, Lu Y, Stein J, Benjamin E. 108; EFFECTS OF THE STABLE PROSTACYCLIN ANALOGUE ILOPROST ON INTESTINAL ACIDOSIS IN ENDOTOXIN-INDUCED MESENTERIC ISCHEMIA. Shock 1994. [DOI: 10.1097/00024382-199401001-00109] [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: 11/25/2022]
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Hannon E, Barry R. Gun control: Iowa physicians have opposing views. Iowa Med 1992; 82:364-6. [PMID: 1399466] [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: 12/26/2022]
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Mauch P, Greenberger JS, Botnick L, Hannon E, Hellman S. Evidence for structured variation in self-renewal capacity within long-term bone marrow cultures. Proc Natl Acad Sci U S A 1980; 77:2927-30. [PMID: 6930675 PMCID: PMC349519 DOI: 10.1073/pnas.77.5.2927] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Bone marrow pluripotent stem cells (CFUs) demonstrate capacity for both proliferation and differentiation. The proliferative capacity of CFUs has been measured by serial transplantability and by the Rs, a measurement of CFU production in a single 14-day transfer. In the present study, the self-renewal capacity fo both adherent and nonadherent CFUs from long-term bone marrow cultures was measured. Culture conditions were established such that nonadherent cells were derived from the adherent cell layer. Both adherent and non-adherent cells produced spleen colonies, demonstrating that significant proliferative potential was present in both locations; however, at all times in culture, the CFUs within the adherent stromal cell layer had a significantly greater self-renewal capacity than did the nonadherent CFUs. During the initial establishment of the cultures, the self-renewal capacity of the adherent CFUs decreased as the total number of CFUs per flask increased. After 3 weeks in culture, the self-renewal potential of the adherent CFUs stabilized and was maintained. These results suggest two different mechanisms of stem cell proliferation. In order to increase the most primitive stem cell pool size, there was initial proliferation of early stem cells with a concomitant decrease in self renewal capacity. Once this pool was established, the self-renewal capacity of the adherent CFUs maintained for 13 weeks in culture suggests that CFU production and cell maintenance were achieved by clonal succession.
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Goodman R, Grate H, Hannon E, Hellman S. Hematopoietic stem cells: effect of preirradiation, bleeding, and erythropoietin on thrombopoietic differentiation. Blood 1977; 49:253-61. [PMID: 318875] [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: 12/14/2022] Open
Abstract
A method of measuring differentiation of stem cells towards platelets is described using syngeneic bone marrow injected into lethally irradiated mice. Fourteen days after such injection, the platelet counts are found to be proportional to the number of bone marrow cells injected and can be used as a measure of platelet progenitors. Perturbation of the milieu in which the transplanted marrow is placed by host preirradiation, bleeding, or erythropoietin administration leads to enhanced thrombopoiesis. It has been shown previously that similar perturbation favors erythropoiesis at the expense of granulopoiesis. The data from these and other experiments appear to be consistent, with a model of the stem cell compartment as a continuum with proliferative activity increasing as commitment is restricted. These functions vary inversely with the capacity for self-renewal. The various stem cell assays measure different ranges of stem cells, but overlap within this continuum.
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Hellman S, Hannon E. Letter: Effects of adriamycin on the radiation response of murine hematopoietic stem cells. Radiat Res 1976; 67:162-7. [PMID: 940929] [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: 12/25/2022]
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