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Effects of ECG Signal Processing on the Inverse Problem of Electrocardiography. COMPUTING IN CARDIOLOGY 2019; 45. [PMID: 30899762 DOI: 10.22489/cinc.2018.070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The inverse problem of electrocardiography is ill-posed. Errors in the model such as signal noise can impact the accuracy of reconstructed cardiac electrical activity. It is currently not known how sensitive the inverse problem is to signal processing techniques. To evaluate this, experimental data from a Langendorff-perfused pig heart (n=1) suspended in a human-shaped torso-tank was used. Different signal processing methods were applied to torso potentials recorded from 128 electrodes embedded in the tank surface. Processing methods were divided into three categories i) high-frequency noise removal ii) baseline drift removal and iii) signal averaging, culminating in n=72 different signal sets. For each signal set, the inverse problem was solved and reconstructed signals were compared to those directly recorded by the sock around the heart. ECG signal processing methods had a dramatic effect on reconstruction accuracy. In particular, removal of baseline drift significantly impacts the magnitude of reconstructed electrograms, while the presence of high-frequency noise impacts the activation time derived from these signals (p<0.05).
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Abstract
Gastric volvulus is a rare complication of diaphragmatic rupture. We report the case of an 82-year-old man who presented following an out-of-hospital cardiac arrest. Chest radiography and thoracic computed tomography revealed an acute gastric volvulus and a chronic diaphragmatic hernia containing transverse colon and abdominal viscera. He had complained of retching and associated epigastric pain prior to collapse, and had sustained a motorcycle accident approximately 60 years earlier. Insertion of a nasogastric tube was unsuccessful (completing Borchardt's diagnostic triad) and his condition prevented both operative and endoscopic reduction of his volvulus. He died soon afterwards.
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K01 Patient Views On The Delivery Of Predictive Test Counselling Services For Huntington's Disease. Journal of Neurology, Neurosurgery and Psychiatry 2014. [DOI: 10.1136/jnnp-2014-309032.225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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4
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Long-term radio frequency scar behavior after ablation of atrial fibrillation: lessons learned from LGE-MRI analysis. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht307.p496] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Poster Session 2. Europace 2011. [DOI: 10.1093/europace/eur222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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How climate change might influence the starvation-predation risk trade-off response. Proc Biol Sci 2009; 276:3553-60. [PMID: 19625317 DOI: 10.1098/rspb.2009.1000] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Climate change within the UK will affect winter starvation risk because higher temperatures reduce energy budgets and are likely to increase the quality of the foraging environment. Mass regulation in birds is a consequence of the starvation-predation risk trade-off: decreasing starvation risk because of climate change should decrease mass, but this will be countered by the effects of predation risk, because high predation risk has a negative effect on mass when foraging conditions are poor and a positive effect on mass when foraging conditions are good. We tested whether mass regulation in great tits (Parus major) across the UK was related to temporal changes in starvation risk (winter temperature 1995-2005) and spatial changes in predation risk (sparrowhawk Accipiter nisus abundance). As predicted, great tits carried less mass during later, warmer, winters, demonstrating that starvation risk overall has decreased. Also, the effects of predation risk interacted with the effects of temperature (as an index of foraging conditions), so that in colder winters higher sparrowhawk abundance led to lower mass, whereas in warmer, later, winters higher sparrowhawk abundance led to higher mass. Mass regulation in a small bird species may therefore provide an index of how environmental change is affecting the foraging environment.
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Immune mechanisms leading to abnormal B cell selection and activation in New Zealand Black mice. Eur J Immunol 2007; 37:2645-56. [PMID: 17668901 DOI: 10.1002/eji.200737334] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Polyclonal B cell activation is a hallmark of the immune dysregulation in New Zealand Black (NZB) mice. We have previously shown that the splenic B cell activation is associated with increased CD80 expression. Here we show that abnormal expansions of CD80-expressing GC, CD5(+), marginal zone (MZ) precursor and MZ B cells produce this increase. To investigate the role of BCR engagement in the generation and activation of these populations, a non-self-reactive Ig Tg was introduced onto the NZB background. NZB Ig-Tg mice lacked Tg CD5(+) and peanut agglutinin(+) B cells, confirming the role of endogenous Ag in their selection. Although the increased proportion of MZ B cells was retained in NZB Ig-Tg mice, CD80 expression on these cells was reduced as compared to non-Tg NZB mice, suggesting a role for BCR engagement with endogenous Ag in their activation. Examination of CD40L-knockout NZB mice showed no difference in the abnormal activation or selection of the B cell populations, with the exception of GC cells, as compared to wild-type NZB mice. Thus, polyclonal B cell activation in NZB mice does not require CD40 engagement, but results, in part, from dysregulated BCR-specific mechanisms.
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Dissociation of the genetic loci leading to b1a and NKT cell expansions from autoantibody production and renal disease in B6 mice with an introgressed New Zealand Black chromosome 4 interval. THE JOURNAL OF IMMUNOLOGY 2007; 178:1608-17. [PMID: 17237410 DOI: 10.4049/jimmunol.178.3.1608] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Previous mapping studies have linked New Zealand Black (NZB) chromosome 4 to several lupus traits, including autoantibody production, splenomegaly, and glomerulonephritis. To confirm the presence of these traits, our laboratory introgressed homozygous NZB chromosome 4 intervals extending from either 114 to 149 Mb or 32 to 149 Mb onto the lupus-resistant C57BL/6 background (denoted B6.NZBc4S and B6.NZBc4L, respectively). Characterization of aged cohorts revealed that B6.NZBc4L mice exhibited a striking increase in splenic B1a and NKT cells in the absence of high titer autoantibody production and significant renal disease. Tissue-specific expansion of these subsets was also seen in the peritoneum and liver for B1a cells and in the bone marrow for NKT cells. Staining with CD1d tetramers loaded with an alpha-galactosylceramide analog (PBS57) demonstrated that the expanded NKT cell population was mainly CD1d-dependent NKT cells. The lack of both cellular phenotypes in B6.NZBc4S mice demonstrates that the genetic polymorphism(s) that result in these phenotypes are on the proximal region of NZB chromosome 4. This study confirms the presence of a locus that promotes the expansion of B1a cells and newly identifies a region that promotes CD1d-restricted NKT cell expansion on NZB chromosome 4. Taken together, the data indicate that neither an expansion of B1a cells and/nor NKT cells is sufficient to promote autoantibody production and ultimately, renal disease.
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410 POSTER Identification and characterization of novel, orally active inhibitors of c-MET and Ron receptor tyrosine kinases. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70415-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Use of MRI and audiological tests in presymptomatic diagnosis of type 2 neurofibromatosis (NF2). J Med Genet 2000; 37:944-7. [PMID: 11186935 PMCID: PMC1734490 DOI: 10.1136/jmg.37.12.944] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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A G1 cell cycle arrest induced by ligands of the reovirus type 3 receptor is secondary to inactivation of p21ras and mitogen-activated protein kinase. DNA Cell Biol 1999; 18:763-70. [PMID: 10541435 DOI: 10.1089/104454999314908] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The reovirus type 3 S1 gene product (type 3 hemagglutinin; HA3) is the viral protein responsible for binding to a mammalian cell-surface receptor. It has been shown that HA3 binding to its receptor inhibits cell growth, even in the continuous presence of serum mitogens. Here, receptor-mediated signal transduction leading to growth arrest was studied after binding with synthetic or recombinant ligands in the absence of viral infection. Receptor ligation caused rapid inactivation of p21(ras), a decrease in Raf phosphorylation and in mitogen-activated protein kinase (MAPK) enzymatic activity, and G1 cell cycle arrest. Transfection and expression of constitutively active v-Has-ras prevented the G1 arrest, indicating that inactivation of p21(ras) is causative. Interestingly, v-Has-ras expression also decreased the efficiency of reoviridae replication, suggesting that inactivation of p21(ras) signals is required at some step of the viral cycle. This study may define new mechanisms regulating cell growth and support the approach of using viral proteins to identify and study cellular receptors. Synthetic receptor ligands with antiproliferative properties may be useful in drug development with the aim of blocking mitosis.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Capsid Proteins
- Cell Cycle Proteins
- Cell Division/drug effects
- Cytopathogenic Effect, Viral
- G1 Phase/drug effects
- Genes, ras
- Growth Inhibitors/chemistry
- Growth Inhibitors/pharmacology
- Guanosine Diphosphate/metabolism
- Guanosine Triphosphate/metabolism
- Humans
- Ligands
- MAP Kinase Signaling System/drug effects
- Mammalian orthoreovirus 3/physiology
- Mice
- Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Oncogene Protein p21(ras)/antagonists & inhibitors
- Oncogene Protein p21(ras)/physiology
- Peptides, Cyclic/pharmacology
- Phosphorylation/drug effects
- Protein Processing, Post-Translational/drug effects
- Protein Structure, Tertiary
- Proto-Oncogene Proteins c-raf/metabolism
- Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors
- Proto-Oncogene Proteins p21(ras)/physiology
- Receptors, Virus/agonists
- Receptors, Virus/physiology
- Recombinant Fusion Proteins/physiology
- Transfection
- Tumor Cells, Cultured
- Viral Proteins/chemistry
- Viral Proteins/immunology
- Viral Proteins/physiology
- Virus Replication/drug effects
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Abstract
Although there has been much debate about the uptake and effects of predictive testing for common cancers, such as breast and colon cancer, little has been published on the more classical tumour predisposing conditions, such as von Hippel-Lindau disease and familial adenomatous polyposis. Since 1990 the genetics departments in Manchester and Cambridge have had a genetic register for cancer predisposing syndromes and presymptomatic testing for these conditions has been offered once this has become possible. To investigate the factors that might influence uptake of genetic testing in familial cancer syndromes we have reviewed our experience. Demand for predictive testing has generally been high, but men had a lower uptake (77%) than a comparable group of women (93%) (p < 0.01).
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Science and democracy: historical reflections on present discontents. MINERVA 1997; 35:369-384. [PMID: 11619816 DOI: 10.1023/a:1004362816974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Root and shoot growth, assimilate partitioning and cell proliferation in roots of Sitka spruce (Picea sitchensis) grown in filtered and unfiltered chambers. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 1996; 92:343-347. [PMID: 15091387 DOI: 10.1016/0269-7491(95)00089-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/1995] [Accepted: 09/18/1995] [Indexed: 05/24/2023]
Abstract
Rooted cuttings of clonal Sitka spruce (Picea sitchensis (Bong.) Carr.) were grown from April to October in 1 m long tubes sunk into the ground inside open top chambers. The same experiment was repeated in each of two consecutive years using a different clone of Sitka spruce each year. Air was either passed directly into the chambers (ambient air) or passed over charcoal filters which removed the majority of gaseous pollutants before entering the chambers (filtered air). Ambient pollution did not appear to influence the growth of Sitka spruce at least over the experimental period used. No significant differences were found between plants exposed to ambient or filtered air in terms of shoot and root dry mass, needle dry mass, root length, carbohydrate content of roots and needles, and in the percentage of meristematic cells close to the apex in each phase or interphase or undergoing mitosis.
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Abstract
1. 2',3'-Dideoxyinosine (ddI) has potent activity against human immunodeficiency virus (HIV). It is converted within target cells to its active form dideoxyadenosine triphosphate(ddA-TP). 2. In addition to the intracellular formation of ddA-TP, ddI can be broken down to hypoxanthine, by purine nucleoside phosphorylase (PNP) and to uric acid, by xanthine oxidase. Since PNP is present in red blood cells we have examined the metabolism of [14C]-ddI by human blood. 3. When incubated with whole blood at 37 degrees C, ddI was extensively metabolised, principally to hypoxanthine (50.4 +/- 12.5% formed at 6 h; mean +/- s.d.; n = 16). Small amounts of uric acid were formed (3.8 +/- 2.4%). 4. ddI breakdown was temperature dependent, being virtually negligible at 4 degrees C. Metabolism to hypoxanthine occurred within red blood cells. 5. The short half-life of ddI in patients is probably the result of both hepatic and erythrocytic metabolism.
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In vitro inhibition studies of the glucuronidation of 3'-azido-3'-deoxythymidine catalysed by human liver UDP-glucuronosyl transferase. Biochem Pharmacol 1992; 43:382-6. [PMID: 1739424 DOI: 10.1016/0006-2952(92)90303-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Actions of intravenous magnesium on ventricular arrhythmias caused by acute myocardial infarction. J Pharmacol Exp Ther 1991; 259:939-46. [PMID: 1941638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Although the antiarrhythmic properties of magnesium are well recognized, its mechanisms of antiarrhythmic action are poorly understood. This study was designed to characterize the effects of magnesium on ventricular tachyarrhythmias related to acute myocardial infarction (MI) in dogs. When the circumflex coronary artery was occluded repeatedly for 10 min at 30-min intervals, ventricular fibrillation (VF) occurred in 30, 35 and 33% of dogs during occlusions 1, 2 and 3, respectively. Magnesium pretreatment reduced the incidence of VF to 14% during occlusion 3 (P less than .05 compared to occlusions without magnesium pretreatment). Neither the prevalence of ventricular ectopic complexes 24 h after MI nor arrhythmia inducibility 4 days after infarction were significantly altered by i.v. magnesium. Magnesium significantly attenuated the ST segment elevation (an index of ischemic injury) and ventricular conduction slowing caused by MI. Because magnesium has been reported to reverse the effects of hyperkalemia, we evaluated the role of this action by infusing potassium directly into a coronary artery (to mimic ischemia-induced hyperkalemia) and administered i.v. magnesium. Potassium infusion markedly slowed intraventricular conduction, an effect fully reversed by discontinuing potassium administration but unaffected by i.v. magnesium. We conclude that magnesium has antiarrhythmic actions only during the early phases of an experimental MI, and that these actions are associated with attenuation of indices of ischemic injury and conduction slowing. These properties of magnesium are similar to those of calcium antagonists, and suggest that magnesium's calcium antagonist properties may be important in its antiarrhythmic actions.
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Managing capital assets. NEW ZEALAND HEALTH & HOSPITAL 1989; 41:9-11. [PMID: 10295404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Experimental evidence of a relationship between turnip yellow mosaic virus and wild cucumber mosaic virus. Virology 1963. [DOI: 10.1016/0042-6822(63)90008-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Deformity of the Hands Caused by Absorption of the Phalangeal Bones. THE INDIAN MEDICAL GAZETTE 1885; 20:67-68. [PMID: 29001380 PMCID: PMC5184693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Dr. Macleod on the Statistics of Rheumatism. West J Med 1842; 4:19-21. [DOI: 10.1136/bmj.s1-4.1.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Remarks on the Use of Prussic Acid in Affections of the Stomach and Heart. THE LONDON MEDICAL AND PHYSICAL JOURNAL 1823; 50:462-464. [PMID: 30494520 PMCID: PMC5633431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Quarterly Report (No. 5,) of the Medical Cases Treated at the Westminster General Dispensary, from February 10th to May 10th, 1823. THE LONDON MEDICAL AND PHYSICAL JOURNAL 1823; 49:527-528. [PMID: 30494504 PMCID: PMC5632443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/30/2022]
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Quarterly Report (No. 4;) Being a List of the Medical Cases, Admitted from the 10th of November, 1822, to the 10th of February, 1823, at the Westminster General Dispensary. THE LONDON MEDICAL AND PHYSICAL JOURNAL 1823; 49:259-262. [PMID: 30494462 PMCID: PMC5632390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Report of Diseases Prevailing among Adults, from May to August 1822. THE LONDON MEDICAL AND PHYSICAL JOURNAL 1822; 48:267-272. [PMID: 30494644 PMCID: PMC5634191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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On a New Property of the Hydrocyanic Acid Taken Internally. THE LONDON MEDICAL AND PHYSICAL JOURNAL 1821; 46:359-363. [PMID: 30494335 PMCID: PMC5626059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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