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Ekhator C, Grezenko H, Haider Z, Ali Cheema U, Haider H, Mohsin SN, Affaf M, Bellegarde SB, Amir S, Kumar S, Shehryar A, Arif S, Fareed MU, Rehman A. Beneath the Layers: Deciphering the Molecular Pathways, Therapeutic Avenues, and Neurological Connections of Soft Tissue Sarcomas. Cureus 2023; 15:e44694. [PMID: 37674761 PMCID: PMC10477814 DOI: 10.7759/cureus.44694] [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] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2023] [Indexed: 09/08/2023] Open
Abstract
Soft tissue sarcomas (STSs) are a heterogeneous group of malignancies that have long posed challenges in terms of diagnosis, treatment, and management. This narrative review provides a comprehensive exploration into the multifaceted realm of STS, spanning from its historical origins to the latest advancements in research and clinical care. We delve into the molecular intricacies of STS, highlighting the genetic and epigenetic aberrations that drive these tumors. The review emphasizes the neurological implications of STS, a relatively underexplored area, shedding light on the interplay between tumor biology and neural processes. The evolving therapeutic landscape is discussed, with a focus on the promise of targeted therapies, immunotherapy, and precision medicine. A significant portion is dedicated to the patient-centric approach, underscoring the importance of holistic care that addresses both the physical and psychological needs of STS patients. Furthermore, we highlight the gaps in current research and clinical practices, offering insights into potential avenues for future exploration. This review serves as a valuable resource for clinicians, researchers, and the broader scientific community, encapsulating the current state of STS knowledge and pointing toward future directions in this dynamic field.
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Affiliation(s)
- Chukwuyem Ekhator
- Neuro-oncology, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, USA
| | - Han Grezenko
- Translational Neuroscience, Barrow Neurological Institute, Phoenix, USA
| | - Zaroon Haider
- Internal Medicine, CMH Lahore Medical College and Institute of Dentistry, Lahore, PAK
| | | | - Haseeb Haider
- Medicine and Surgery, CMH Multan Institute of Medical Sciences, Multan, PAK
| | | | - Maryam Affaf
- Internal Medicine, Women's Medical and Dental college, Abbottabad, PAK
| | - Sophia B Bellegarde
- Pathology and Laboratory Medicine, American University of Antigua, St. John's, ATG
| | - Saniya Amir
- Accident and Emergency, Liaquat National Hospital and Medical College, Karachi, PAK
| | - Sahil Kumar
- Medicine, Liaquat National Hospital, Karachi, PAK
| | | | - Sidra Arif
- Urology, Jinnah Postgraduate Medical Center, Karachi, PAK
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Shamah SP, Chapman CG, Haider H, Liao C, Waxman I, Siddiqui UD. Partially Covered Versus Uncovered Self-Expandable Metal Stents: Coating Nor Diameter Affect Clinical Outcomes. Dig Dis Sci 2019; 64:2631-2637. [PMID: 31041643 DOI: 10.1007/s10620-019-05643-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/23/2019] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Jaundice is a common initial presentation of malignant biliary stricture. In patients with life expectancies that are greater than 3 months, self-expanding metal stents (SEMS) offer a larger diameter stent with longer patency and fewer complications compared to plastic stents. There have been conflicting results in the published literature as to efficacy and safety between the various SEMS types and diameters. We compared stent coating (PCSEMS vs USEMS) and diameter on clinical outcomes regarding management of malignant biliary obstruction. METHODS A retrospective cohort study was conducted using a database of consecutive patients who underwent an ERCP with biliary SEMS placement (only 8 and 10 mm) between 2009 and 2017. RESULTS In total, 278 patients who had SEMS at ERCP for malignant biliary obstruction were included (213 PCSEMS vs 65 USEMS). The groups were demographically evenly matched. Clinical success rates and patency duration were not statistically significant between PCSEMS and USEMS (98.1% vs 95.5%, P = 0.36, and 302.5 vs 225.5 days, P = 0.72, respectively). Adverse event rates were similar between both PCSEMS and USEMS with regard to overall adverse events. Stent diameter did not have an impact on overall clinical success (98.9% vs 95.3%, P = 0.11) or patency duration (239 days vs 336 days, P = 0.51). CONCLUSIONS Our comparison of PCSEMS versus USEMS and 8 mm versus 10 mm showed no difference in clinical efficacy or adverse events between the two SEMS coatings and diameter, illustrating that coating and size do not matter in regard to stent choice, despite prior suggestive data.
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Affiliation(s)
- S P Shamah
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA.
| | - C G Chapman
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA
| | - H Haider
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA
| | - C Liao
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA
| | - I Waxman
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA
| | - U D Siddiqui
- Center for Endoscopic Research and Therapeutics (CERT), University of Chicago Medicine, 5700 S. Maryland Avenue, MC 8043, Chicago, IL, 60637, USA
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Cima RFF, Mazurek B, Haider H, Kikidis D, Lapira A, Noreña A, Hoare DJ. A multidisciplinary European guideline for tinnitus: diagnostics, assessment, and treatment. HNO 2019; 67:10-42. [DOI: 10.1007/s00106-019-0633-7] [Citation(s) in RCA: 157] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Gran R, Betancourt M, Elkins M, Rodrigues PA, Akbar F, Aliaga L, Andrade DA, Bashyal A, Bellantoni L, Bercellie A, Bodek A, Bravar A, Budd H, Vera GFRC, Cai T, Carneiro MF, Coplowe D, da Motta H, Dytman SA, Díaz GA, Felix J, Fields L, Fine R, Gallagher H, Ghosh A, Haider H, Han JY, Harris DA, Henry S, Jena D, Kleykamp J, Kordosky M, Le T, Leistico JR, Lovlein A, Lu XG, Maher E, Manly S, Mann WA, Marshall CM, McFarland KS, McGowan AM, Messerly B, Miller J, Mislivec A, Morfín JG, Mousseau J, Naples D, Nelson JK, Nguyen C, Norrick A, Olivier A, Paolone V, Patrick CE, Perdue GN, Ramírez MA, Ransome RD, Ray H, Ren L, Rimal D, Ruterbories D, Schellman H, Salinas CJS, Su H, Sultana M, Falero SS, Valencia E, Wolcott J, Wospakrik M, Yaeggy B. Antineutrino Charged-Current Reactions on Hydrocarbon with Low Momentum Transfer. Phys Rev Lett 2018; 120:221805. [PMID: 29906174 DOI: 10.1103/physrevlett.120.221805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 04/17/2018] [Indexed: 06/08/2023]
Abstract
We report on multinucleon effects in low momentum transfer (<0.8 GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.
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Affiliation(s)
- R Gran
- Department of Physics and Astronomy, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA
| | - M Betancourt
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - M Elkins
- Department of Physics and Astronomy, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA
| | - P A Rodrigues
- Oxford University, Department of Physics, Oxford, United Kingdom
- University of Mississippi, Oxford, Mississippi 38677, USA
- University of Rochester, Rochester, New York 14627 USA
| | - F Akbar
- AMU Campus, Aligarh, Uttar Pradesh 202001, India
| | - L Aliaga
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
- Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
| | - D A Andrade
- Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato 36000, México
| | - A Bashyal
- Department of Physics, Oregon State University, Corvallis, Oregon 97331, USA
| | - L Bellantoni
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - A Bercellie
- University of Rochester, Rochester, New York 14627 USA
| | - A Bodek
- University of Rochester, Rochester, New York 14627 USA
| | - A Bravar
- University of Geneva, 1211 Geneva 4, Switzerland
| | - H Budd
- University of Rochester, Rochester, New York 14627 USA
| | - G F R Caceres Vera
- Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil
| | - T Cai
- University of Rochester, Rochester, New York 14627 USA
| | - M F Carneiro
- Department of Physics, Oregon State University, Corvallis, Oregon 97331, USA
| | - D Coplowe
- Oxford University, Department of Physics, Oxford, United Kingdom
| | - H da Motta
- Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil
| | - S A Dytman
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - G A Díaz
- University of Rochester, Rochester, New York 14627 USA
- Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
| | - J Felix
- Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato 36000, México
| | - L Fields
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
- Northwestern University, Evanston, Illinois 60208, USA
| | - R Fine
- University of Rochester, Rochester, New York 14627 USA
| | - H Gallagher
- Physics Department, Tufts University, Medford, Massachusetts 02155, USA
| | - A Ghosh
- Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, Rio de Janeiro 22290-180, Brazil
- Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile
| | - H Haider
- AMU Campus, Aligarh, Uttar Pradesh 202001, India
| | - J Y Han
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - D A Harris
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - S Henry
- University of Rochester, Rochester, New York 14627 USA
| | - D Jena
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - J Kleykamp
- University of Rochester, Rochester, New York 14627 USA
| | - M Kordosky
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - T Le
- Physics Department, Tufts University, Medford, Massachusetts 02155, USA
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - J R Leistico
- Department of Physics and Astronomy, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA
| | - A Lovlein
- Department of Physics and Astronomy, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA
| | - X-G Lu
- Oxford University, Department of Physics, Oxford, United Kingdom
| | - E Maher
- Massachusetts College of Liberal Arts, 375 Church Street, North Adams, Massachusetts 01247, USA
| | - S Manly
- University of Rochester, Rochester, New York 14627 USA
| | - W A Mann
- Physics Department, Tufts University, Medford, Massachusetts 02155, USA
| | - C M Marshall
- University of Rochester, Rochester, New York 14627 USA
| | - K S McFarland
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
- University of Rochester, Rochester, New York 14627 USA
| | - A M McGowan
- University of Rochester, Rochester, New York 14627 USA
| | - B Messerly
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - J Miller
- Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile
| | - A Mislivec
- University of Rochester, Rochester, New York 14627 USA
| | - J G Morfín
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - J Mousseau
- University of Florida, Department of Physics, Gainesville, Florida 32611, USA
| | - D Naples
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - J K Nelson
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - C Nguyen
- University of Florida, Department of Physics, Gainesville, Florida 32611, USA
| | - A Norrick
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - A Olivier
- University of Rochester, Rochester, New York 14627 USA
| | - V Paolone
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - C E Patrick
- Northwestern University, Evanston, Illinois 60208, USA
| | - G N Perdue
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
- University of Rochester, Rochester, New York 14627 USA
| | - M A Ramírez
- Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato 36000, México
| | - R D Ransome
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - H Ray
- University of Florida, Department of Physics, Gainesville, Florida 32611, USA
| | - L Ren
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - D Rimal
- University of Florida, Department of Physics, Gainesville, Florida 32611, USA
| | - D Ruterbories
- University of Rochester, Rochester, New York 14627 USA
| | - H Schellman
- Department of Physics, Oregon State University, Corvallis, Oregon 97331, USA
- Northwestern University, Evanston, Illinois 60208, USA
| | | | - H Su
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - M Sultana
- University of Rochester, Rochester, New York 14627 USA
| | - S Sánchez Falero
- Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú
| | - E Valencia
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
- Campus León y Campus Guanajuato, Universidad de Guanajuato, Lascurain de Retana No. 5, Colonia Centro, Guanajuato 36000, México
| | - J Wolcott
- University of Rochester, Rochester, New York 14627 USA
| | - M Wospakrik
- University of Florida, Department of Physics, Gainesville, Florida 32611, USA
| | - B Yaeggy
- Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680 Casilla 110-V, Valparaíso, Chile
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Hinterhofer C, Ferguson JC, Apprich V, Haider H, Stanek C. A finite element model of the bovine claw under static load for evaluation of different flooring conditions. N Z Vet J 2011; 53:165-70. [PMID: 16012586 DOI: 10.1080/00480169.2005.36501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AIM To create a computer-based finite element (FE) model of the bovine claw and to use finite element analysis (FEA) to estimate stress and deformation of a physiologically-shaped model claw under static load, to visualise potential material weakness and to evaluate the effect of different flooring conditions. METHODS Model geometry was derived using digitalised images from a recently trimmed, sound, hind claw from a 4-year-old Austrian Fleckvieh cow. Material properties of bovine claw horn were defined from preliminary investigations and recently established material data, using a modulus of elasticity from 200 to 600 N/mm2. Meshing of the model was performed with 42,127 elements based on 116,141 nodes. Loading of the model was defined at 756 N per claw on a hard and soft surface. RESULTS The FE model of the bovine claw under a load of 756 N showed only minimal deformation, most of which took place at the axial wall. Highest stresses were evident in the proximal axial wall, the outer edge of the weight-bearing surface and under the heels. The claw-floor contact image showed a pressure distribution resembling the distal rim of the claw wall. On the hard surface, the maximum stresses were three times higher than those on the soft surface. CONCLUSIONS AND CLINICAL RELEVANCE FEA allowed visualisation of the effects that loading on different floor surfaces have on the biomechanics of the claw. Uneven preparation of the claw sole resulted in high stresses at and close to irregularities of the sole. Consequences were more severe on harder flooring. The model supports the hypothesis that mechanical factors play a substantial role in the pathogenesis of claw lesions.
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Affiliation(s)
- C Hinterhofer
- Orthopaedic Clinic, University of Veterinary Medicine, Vienna, Veterinärplatz 1, A-1210 Vienna, Austria.
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Veres G, Radovits T, Otila G, Hirschberg K, Haider H, Krieger N, Knoll A, Weigang E, Szabolcs Z, Karck M, Szabó G. Efficacy of the non-adenosine analogue A1 adenosine receptor agonist (BR-4935) on cardiovascular function after cardiopulmonary bypass. Thorac Cardiovasc Surg 2010; 58:86-92. [PMID: 20333570 DOI: 10.1055/s-0029-1186271] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND We tested the hypothesis that pharmacological preconditioning with a newly developed, potent non-adenosine analogue A1AdoR agonist (BR-4935) improves biventricular cardiac and endothelial function after cardiopulmonary bypass. METHODS Twelve anesthetized dogs underwent cardiopulmonary bypass. Dogs were divided into two groups: group 1 (n = 6) received saline vehicle, group 2 (n = 6) received BR-4935 before cardiopulmonary bypass. Biventricular hemodynamic variables were measured using a combined pressure-volume conductance catheter. Coronary blood flow, ATP content, malondialdehyde and myeloperoxidase levels and vasodilatative responses to acetylcholine and sodium nitroprusside were also determined. RESULTS Administration of the A1AdoR agonist led to a significantly better recovery of left and right ventricular systolic function after 60 minutes of reperfusion. Although the vasodilatative response to sodium nitroprusside was similar in both groups, acetylcholine resulted in a significantly greater increase in coronary blood flow in the BR-4935 group. In addition, the ATP content was significantly higher in the same group. Furthermore, malondialdehyde and myeloperoxidase levels significantly decreased in the A1AdoR group. CONCLUSION Pharmacological preconditioning with a new, potent non-adenosine analogue A1AdoR agonist improves biventricular function recovery and endothelial function after hypothermic cardiac arrest.
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Affiliation(s)
- G Veres
- Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany
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Affiliation(s)
- A Khalil
- Elizabeth Garrett Anderson and Obstetric Hospital, University College Hospitals, London, UK
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Hinterhofer C, Haider H, Apprich V, Ferguson J, Collins S, Stanek C. Development of a twenty-one-component finite element distal hind limb model: Stress and strain in bovine digit structures as a result of loading on different floorings. J Dairy Sci 2009; 92:972-9. [DOI: 10.3168/jds.2008-1605] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ghaffar A, Siddiqui TS, Haider H, Khatri H. Postsurgical pneumoperitoneum - comparison of abdominal ultrasound findings with plain radiography. J Coll Physicians Surg Pak 2008; 18:477-80. [PMID: 18798583 DOI: 08.2008/jcpsp.477480] [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] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Accepted: 03/21/2008] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To compare abdominal ultrasonography findings with plain radiography in the detection of postsurgical pneumoperitoneum. STUDY DESIGN Cross-sectional, observational. PLACE AND DURATION OF STUDY Radiology Department, PNS Shifa Hospital, Karachi, from October, 2005 to April, 2006. METHODOLOGY Thirty patients of either gender who underwent laparotomies were included in the study. Patients were examined with plain radiography and abdominal ultrasound to detect postsurgical pneumoperitoneum within 24 hours of surgery. Upright chest radiography and left lateral decubitus views of abdomen were used to detect free air. McNemar test was applied to compute relationship between sonographic and radiographic findings. RESULTS Among 30 patients, 22 (73.3%) were females and 8 (26.7%) were males (M: F = 1: 2.75). Average age was 38.07 +/- 12.41 years. Out of 30 patients of postsurgical pneumoperitoneum, 27 (90%) were detected on ultrasonography while 3 (10%) were not detected. On plain X-rays, 4 patients were observed in group-I (no free air) and 26 in group-II (1-10 mm thickness). Significant (p<0.001) relationship was observed between the two findings. CONCLUSION Since both modalities can diagnose pneumoperitoneum reliably, ultrasonography can be a useful alternative imaging modality for the detection of pneumoperitoneum.
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Affiliation(s)
- Abdul Ghaffar
- Department of Diagnostic Radiology, PNS Shifa Hospital, Karachi, Pakistan.
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Wessel J, Rose M, Haider H. Electrophysiological precursors of explicit rule-representation in serial reaction time tasks. Int J Psychophysiol 2008. [DOI: 10.1016/j.ijpsycho.2008.05.470] [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: 10/21/2022]
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Abstract
Arthroplasty outcome is influenced by the ‘quality’ of bone preparation for implant insertion. Surgeons face increasing choices of technique and instrumentation, yet clinical scoring methods assess the overall outcome and patient satisfaction but not the bone cuts directly. ‘Quality management’ of bone reshaping is needed to evaluate different bone cutting methods and computer assisted orthopaedic surgery (CAOS) systems. Analyses and experiments in this study were formulated for measurement and computation of four quantitative characteristics of bone preparation ‘quality’ and produced a highly condensed index for each. These represented (a) surface finish of cuts, (b) implant fit/looseness possible with the cut shape, (c) implant location/misalignment, and (d) accuracy of individual planar cuts. Assessment of synthetic bone cuts verified the robustness of the method for wide application in arthroplasty intraoperatively, in vitro and for comparing navigation systems.
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Affiliation(s)
- O A Barrera
- Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - H Haider
- Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - K L Garvin
- Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
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Hinterhofer C, Apprich V, Polsterer E, Haider H, Stanek C. Comparison of Stress Zones in Finite Element Models of Deformed Bovine Claw Capsules. J Dairy Sci 2007; 90:3690-9. [PMID: 17638980 DOI: 10.3168/jds.2006-817] [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: 11/19/2022]
Abstract
Pathological claw formations occur subsequent to irregular or prolonged claw trimming periods and as a result of improper flooring. Clinical experience and material testing finds horn of minor quality to be associated with the malformations. Finite element models (FEM) of a flat claw (FC), a contracted claw (CC), and a laminitic claw (LC) were designed from native claw specimens to combine material properties and altered claw geometry for stress analysis. The FEM were created by digitizing the typically deformed exungulated claw capsule by means of computed tomography or digital photography. The derived geometry data were meshed with finite elements and the material properties were attributed. Loading was performed via vertical load vectors according to the suspensory and support apparatus of the bovine digit. All FEM were loaded on soft floors. Loading of the FEM of the FC with 756 N exhibited maximum stress values of 3.32 MPa in the dorsal wall, that of the CC exhibited comparably lower stress of 1.33 MPa in the distal abaxial wall, and the model of the LC showed maximum stress of 4.51 MPa in the region of the dorsal border, all at the same loading. The solar surfaces and the corresponding imprints showed stress concentrations in the palmar aspect of the bulb in the FC, a highly stressed bearing margin of the abaxial wall in the CC, and a diffusely stressed sole and bulb in the LC in contrast to the sound claw models. The FEM of the selected pathological claw forms (FC, CC, LC) calculated high stress zones exactly at locations in the claw wall and sole where clinical experts expect the typical claw lesions for these pathologies. These results were obtained simply by exchanging the outer form of the claw capsules; the method of loading and type of flooring for these pathological models were equivalent to those of the sound FEM. It is highly possible that the stress zones derived from these calculations represent corium compression in reality, and these data support the pathophysiological theory that claw lesions may arise as a consequence thereof.
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Affiliation(s)
- C Hinterhofer
- Clinic for Orthopedics in Ungulates, University of Veterinary Medicine, Vienna, Austria.
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Haider H, Tzakis A, Manoharan M, Selvaggi G, Nishida S, Levi D, Ciancio G. Ureteral reconstruction and bladder augmentation using intestinal allograft in a modified multivisceral transplant patient. Am J Transplant 2006; 6:1968-71. [PMID: 16889551 DOI: 10.1111/j.1600-6143.2006.01388.x] [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: 01/25/2023]
Abstract
Segments of ileum are used as conduits following ureteral resection and for bladder augmentation to achieve adequate bladder capacity. We herein report the use of a segment of transplanted ileum for this purpose in a patient with Gardner's syndrome who underwent multivisceral transplantation. To our knowledge this is the first such case report.
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Affiliation(s)
- H Haider
- Department of Surgery, University of Miami, Florida, USA.
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Namavar F, D. Jackson J, G. Sharp J, Varma S, Haider H, Feschuk C, L. Garvin K. Novel Engineered Nanocrystalline Ultra-hydrophilic Hard Ceramic Coatings for Attachment and Growth of Bone Marrow Stromal Cells. ACTA ACUST UNITED AC 2006. [DOI: 10.32604/mcb.2006.003.171] [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: 11/15/2022]
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15
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Hinterhofer C, Ferguson JC, Apprich V, Haider H, Stanek C. Slatted Floors and Solid Floors: Stress and Strain on the Bovine Hoof Capsule Analyzed in Finite Element Analysis. J Dairy Sci 2006; 89:155-62. [PMID: 16357278 DOI: 10.3168/jds.s0022-0302(06)72079-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
An established finite element model of a bovine claw was used to compare mechanical stress levels in a loaded model claw on different types of flooring. The following situations were compared: a claw standing on a solid floor, a claw standing on the edge of a short tie stand, and claws standing on slatted floors with slats of 28 and 40 mm (wide) running parallel and perpendicular to the claw axis. Finite element analysis allowed visualization of stress peaks seen predominantly in the weight-bearing border of the dorsal abaxial wall and of the bulbar region and in the proximal axial wall. Maximum stress values of 13 MPa were found in the model claw loaded on the solid floor and values of 18 to 22 MPa were seen in the model claw loaded on the edge of the solid floor. On slatted floors, stresses increased in the situation in which the claw was not supported under the abaxial wall. Comparison between the other slatted floors showed little difference in amounts of mechanical stress. A clear distinction was detected between the solid floor with full claw contact and the slatted floors. From the point of view of the mechanical stress seen in finite element analysis, a large contact area between claw and floor, as seen in the solid surface floor, is preferable. When use of slatted floors is unavoidable, direction of the slats should run perpendicular to the direction of the walkway to prevent even more mechanical impact in certain footing situations.
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Affiliation(s)
- C Hinterhofer
- Clinic for Orthopaedics in Ungulates, University of Veterinary Medicine, Vienna, Austria.
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16
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Tamu DV, Lüersen K, Eschbach ML, Haider H, Walter RD, Al-Karadaghi S. Crystal structure of Caenorhabditis elegansspermidine synthase: in preparation. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305088860] [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: 11/10/2022] Open
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17
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Abstract
Measurement of the constraint of total knee components in a test machine provides an objective method of describing the laxity and stability characteristics of the implant itself, independent of the knee joint into which it would be implanted. A special fixture was designed and fitted to a Bionix multi-channel loading machine. The test consisted of applying a compressive load, applying a cyclic AP force or internal-external torque, and measuring all of the displacements and rotations. Three different commonly-used TKR's showed widely different constraint characteristics. In the cyclic AP test, along with the cyclic AP displacement, displacements and rotations occurred in the other directions. This indicated that all degrees of freedom should be free to move, otherwise anomalous results would be obtained. The paper concludes with recommendations for standardized constraint tests.
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Affiliation(s)
- H Haider
- Department of Orthopaedic Surgery, University of Nebraska, Omaha, USA
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18
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Abstract
The hypothesis is tested, whether increasing language processing demands draw on the capacity of working memory thereby leading to an increase in theta band power. Previous research has shown that theta reflects working memory whereas upper alpha semantic memory demands. Sentences were presented in four chunks in a reading and a semantic task. In the latter, subjects had to find a superordinate concept to a noun presented in the third chunk. The data show an increase in theta during sentence processing which was significantly smaller in the semantic task. In contrast, the upper alpha band exhibited a significantly larger change in band power during the semantic task and that time window in which subjects searched for the superordinate concept. Thus, we conclude that semantic processing does not draw selectively on the capacity of working memory and that different linguistic processes have no direct influence on theta oscillations.
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Affiliation(s)
- D Röhm
- University of Salzburg, Department of Physiological Psychology, Institute of Psychology, Hellbrunnerstrasse 34, A-5020 Salzburg, Austria.
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19
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Abstract
A finite element (FE) hoof capsule was built as a small, symmetrical forelimb hoof on IDEAS* as a model for calculation and visualisation of stress and displacement of the equine hoof capsule. The model's loading was performed according to the suspension of the coffin bone within the hoof wall (pulling force) and over the sole and frog (compressing force) with a total of 3000 N. Restraints of the model's ground nodes and surface wall nodes were defined for simulation of 4 shoeing situations: a regular horseshoe, a horseshoe with a toe clip, a horseshoe with regular side clips and a horseshoe with a toe clip and more caudally-placed side clips, all fixed to the hoof capsule with 3 nails on each side and each calculated in a tense and a loose nailed condition. Von Mises stresses were taken ranging from 1.22 N/mm2 in the weightbearing border of the side clip shoe fixed loosely to the capsule up to 16.67 N/mm2 in the hoof horn material surrounding the third nail. Further high stress zones were calculated in the proximal dorsal wall, the distal heel and the lateral hoof wall. Displacement values were taken showing movements of hoof wall, sole and frog according to the shoeing conditions. Maximal displacement was calculated in the hoof capsule shod with a regular horseshoe without a clip. Minimal displacement was found in the capsule with a toe clip and 2 side clips placed behind the 3rd nail. All models showed higher displacements when calculated with a loose nail fixation. Validation of the detailed features of the models is not yet possible. Finite element analysis (FEA) can be used practically to predict influences of various farrier techniques on the equine hoof in order to avoid possible harm to horses' feet in field studies.
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Affiliation(s)
- C Hinterhofer
- Clinic of Orthopedics in Ungulates, University of Veterinary Medicine, Veterinärplatz 1, Vienna, Austria
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20
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Riecker A, Ackermann H, Wildgruber D, Meyer J, Dogil G, Haider H, Grodd W. Articulatory/phonetic sequencing at the level of the anterior perisylvian cortex: a functional magnetic resonance imaging (fMRI) study. Brain Lang 2000; 75:259-276. [PMID: 11049668 DOI: 10.1006/brln.2000.2356] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Damage to the anterior peri-intrasylvian cortex of the dominant hemisphere may give rise to a fairly consistent syndrome of articulatory deficits in the absence of relevant paresis of orofacial or laryngeal muscles (apraxia of speech, aphemia, or phonetic disintegration). The available clinical data are ambiguous with respect to the relevant lesion site, indicating either dysfunction of the premotor aspect of the lower precentral gyrus or the anterior insula in the depth of the Sylvian fissure. In order to further specify the functional anatomic substratum of this syndrome, functional magnetic resonance imaging (fMRI) was performed during reiteration of syllables differing in their demands on articulatory/phonetic sequencing (CV versus CCCV versus CVCVCV). Horizontal tongue movements and a polysyllabic lexical item served as control conditions. Repetition of the CV and CCCV monosyllables elicited a rather bilateral symmetric hemodynamic response at the level of the anterior and posterior bank of the central sulcus (primary sensorimotor cortex), whereas a more limited area of neural activity arose within this domain during production of lexical and nonlexical polysyllables, significantly or exclusively lateralized toward the left hemisphere. There is neurophysiological evidence that primary sensorimotor cortex mediates the "fractionation" of movements. Assuming that the polysyllables considered are organized as coarticulated higher-order units, the observed restricted and lateralized cortical activation pattern, most presumably, reflects a mode of "nonindividualized" motor control posing fewer demands on "movement fractionation." These findings may explain the clinical observation of disproportionately worse repetition of trisyllabic items as compared to monosyllables in apraxia of speech. The various test materials failed to elicit significant activation of the anterior insula. If at all, only horizontal tongue movements yielded a hemodynamic reaction extending beyond the sensorimotor cortex to premotor areas. Since limbic projections target the inferior dorsolateral frontal lobe, the enlarged region of activation during horizontal tongue movements might reflect increased attentional requirements of this task.
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Affiliation(s)
- A Riecker
- Department of Neurology, University of Tübingen, Germany
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21
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DesJardins JD, Walker PS, Haider H, Perry J. The use of a force-controlled dynamic knee simulator to quantify the mechanical performance of total knee replacement designs during functional activity. J Biomech 2000; 33:1231-42. [PMID: 10899332 DOI: 10.1016/s0021-9290(00)00094-4] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The experimental evaluation of any total knee replacement (TKR) design should include the pre-implantation quantification of its mechanical performance during tests that simulate the common activities of daily living. To date, few dynamic TKR simulation studies have been conducted before implantation. Once in vivo, the accurate and reproducible assessment of TKR design mechanics is exceedingly difficult, with the secondary variables of the patient and the surgical technique hindering research. The current study utilizes a 6-degree-of-freedom force-controlled knee simulator to quantify the effect of TKR design alone on TKR mechanics during a simulated walking cycle. Results show that all eight TKR designs tested elicited statistically different measures of tibial/femoral kinematics, simulated soft tissue loading, and implant geometric restraint loading during an identical simulated gait cycle, and that these differences were a direct result of TKR design alone. Maximum ranges of tibial kinematics over the eight designs tested were from 0.8mm anterior to 6.4mm posterior tibial displacement, and 14.1 degrees internal to 6.0 degrees external tibial rotation during the walking cycle. Soft tissue and implant reaction forces ranged from 106 and 222N anteriorly to 19 and 127N posteriorly, and from 1.6 and 1.8Nm internally to 3.5 and 5.9Nm externally, respectively. These measures provide valuable experimental insight into the effect of TKR design alone on simulated in vivo TKR kinematics, bone interface loading and soft tissue loading. Future studies utilizing this methodology should investigate the effect of experimentally controlled variations in surgical and patient factors on TKR performance during simulated dynamic activity.
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Affiliation(s)
- J D DesJardins
- Centre for Biomedical Engineering, University College London, Royal National Orthopaedic Hospital Trust, Stanmore, UK.
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22
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Walker PS, Blunn GW, Perry JP, Bell CJ, Sathasivam S, Andriacchi TP, Paul JP, Haider H, Campbell PA. Methodology for long-term wear testing of total knee replacements. Clin Orthop Relat Res 2000:290-301. [PMID: 10738439 DOI: 10.1097/00003086-200003000-00032] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This article begins to address the validation requirements of wear testing on total knee replacements in a knee simulator. The knee simulator has four stations. The axial force is variable but reaches a maximum of 2.3 kN. Physiologic anteroposterior shear force and rotational torques are supplied to the knee. The forces and displacements are timed to coincide with those of a typical gait cycle. Kinematics of the simulator are dependent on the type of knee being tested. Tests of designs with well known clinical histories were done to 10 million cycles. The relative amounts and types of wear shown by the designs were similar to that found in their clinical histories. Wear tracks on more conforming designs were larger, and the penetration into the plastic appeared to be less. This did not necessarily mean that wear, as measured by loss of material, was reduced on conforming designs. Delamination of the plastic was achieved only after aging the tibial components. Wear particles isolated from the lubricating fluid were similar in size and shape to those isolated from in vivo specimens. However, the relative amounts of wear particle shapes were different depending on the design. At the start of the tests, all of the flexibly mounted tibial components showed more motion than after 5 million cycles, indicating that the surface of the plastic became more conforming. This study showed that knee wear similar to wear observed in vivo can be reproduced in the laboratory. The parameters and methods elucidated in this introductory study should form the basis for use in preclinical wear tests of total knee replacements.
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Affiliation(s)
- P S Walker
- Centre for Biomedical Engineering, University College London, Royal National Orthopaedic Hospital Trust, Stanmore, United Kingdom
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23
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Hinterhofer C, Stanek C, Haider H. The effect of flat horseshoes, raised heels and lowered heels on the biomechanics of the equine hoof assessed by finite element analysis (FEA). J Vet Med A Physiol Pathol Clin Med 2000; 47:73-82. [PMID: 10803106 DOI: 10.1046/j.1439-0442.2000.00263.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The biomechanical effects of lowering and raising the heels were studied using a finite element (FE) computer model of the equine hoof capsule consisting of 18,635 finite elements. A static load of 3000 N was distributed to nodes of the inner hoof wall (80%) according to the suspension of the coffin bone, 20% loaded sole and frog. When loaded the FE hoof capsules showed the following deformations: the proximal dorsal wall moves back, the quarters flare to the side and sole and frog perform a downward movement. Stresses are high in the material surrounding the quarter nails, in the heels and in the proximal dorsal wall. Three types of horseshoes were simulated, a regular shoe with flat branches, a shoe with 5 degrees raised heels and a shoe with 5 degrees lowered heels. Raising the heels resulted in significantly (P < 0.05) low stress and displacement values. The lowered heels model calculated highest stress and displacement values and the results of the FE model with the regular horseshoe were found in between.
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Affiliation(s)
- C Hinterhofer
- Clinic of Orthopaedics in Ungulates, University of Veterinary Medicine Vienna, Austria.
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24
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Abstract
Catastrophic failure of tibial baseplates due to fatigue fracture have occurred in patients. The International Standards Organisation (ISO) have proposed an endurance test to ensure a safety level for trays with respect to this problem. At present the magnitude of the applied load has not been defined. The purpose of this study is to evaluate the ISO test by comparing the results of two tibial trays: one with a clinical history of fracture of the tibial baseplate in some cases (Kinematic) and one without such a record (Kinemax). A load of 2000 N was selected, representing the peak force during the normal walking cycle. Finite element analysis (FEA) predicted that both the Kinematic and Kinemax trays would rapidly fail for two defined contact positions. Mechanical testing performed on both these components confirmed the FEA predictions. However, under service conditions, the Kinematic tray has been reported to have a failure of only 1-2%, the failure occurring at a mean of 54 months for early fracture and 7 years for late fracture. There are no published reports of failed Kinemax trays. It is concluded that the ISO test is an exaggeration of reality when a physiological load is used. As a result of our study we propose that a load of 500 N would effectively screen components with respect to the ISO test conditions for the likelihood of fracture.
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Affiliation(s)
- S P Ahir
- Centre for Biomedical Engineering, University College London, Royal National Orthopaedic Hospital Trust, Stanmore, Middlesex UK
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25
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Abstract
To investigate how adenoid hypertrophy and subsequent adenoidectomy affect pediatric airway resistance, we developed a prospective controlled study. Fifty children, aged 3 to 12 years, diagnosed with adenoid hypertrophy and selected for adenoidectomy, preoperatively had their nasal airway resistance assessed by active anterior rhinomanometry. Twenty-five of these children were subsequently followed up postoperatively, undergoing nasal resistance evaluations at 1 month, 3 months, 6 months, and 12 months. Another 25 children, without chronic upper airway obstruction symptoms, were enrolled as a control group, and their airway resistance was assessed in the same fashion. We concluded that the children selected for adenoidectomy, compared to the control group and before surgery, had mean resistance values up to two- to threefold higher, in both untreated and decongested nose states. Surgery was found to dramatically reduce airway resistance, but only in children under the age of seven. However, the postoperative values still tended to remain higher than the control subjects results. If in a significant number of children the operation failed in completely resolving their complaints, no pre-operative rhinomanometric pattern could be found to specifically relate to a complete surgical success.
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Affiliation(s)
- P B Dinis
- Department of Otorhinolaryngology, Hospital de Pulido Valente, Lisbon, Portugal
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26
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Dinis PB, Haider H, Gomes A. Rhinomanometry, sinus CT-scan and allergy testing in the diagnostic assessment of chronic nasal obstruction. Rhinology 1997; 35:158-60. [PMID: 9532634] [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: 02/07/2023]
Abstract
In order to assess how effective a combination of diagnostic methods, each addressing specific aetiopathogenic aspects, would be in uncovering the cause of common chronic nasal obstruction, we evaluated 45 consecutive adult subjects. They were submitted to rhinomanometry testing, sinus CT-scans and RASTs to prevalent allergens. Most, but not all, patients ended up showing abnormal results in at least one of the diagnostic procedures. Sinus pathology was, by far, the most frequent diagnosis, while allergy took second place, with a number of atopic subjects displaying sinusitis as well. On the other hand, septal deviations with a significant effect on nasal resistance were only seldom found to be the cause of chronic nasal obstruction.
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Affiliation(s)
- P B Dinis
- Department of Otorhinolaryngology, Hospital de Pulido Valente, Lisbon, Portugal
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Hinterhofer C, Stanek C, Haider H. Simulation of pressure by means of a finite element computer model of the equine hoof capsule. PFERDEHEILKUNDE 1997. [DOI: 10.21836/pem19970402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Abstract
Theories of skill acquisition assume that the effects of practice on task performance are due to either qualitative changes in the task structure, an increased efficiency of performing individual task components, an increased efficiency of performing sequences of task components, or some combination of these mechanisms. We propose an extension to the existing theories by arguing that for many tasks, practice affects which information is processed. More specifically, we argue that people learn, over the course of practice, to separate task-relevant from task-redundant information, and to limit their processing to relevant aspects of the task. In three experiments, subjects verified alphabetic strings, such as M [4] R S T. Strings were correct if they followed the alphabet when the number of letters, given by the digit in parentheses, was skipped. Strings were constructed such that errors occurred only within the initial "letter-digit-letter" triplet. Analyses of subjects' RTs for strings of varying lengths demonstrated that: (a) subjects were able to distinguish relevant from redundant task information, and to limit their processing to the relevant information, (b) the ability to reduce the amount of information that is processed takes time and develops gradually over the course of practice, and (c) the mechanism underlying this ability appears to be largely stimulus-independent in the sense that structural components of a task are ignored, rather than specific task information. The findings and their implications for general theories of skill acquisition are discussed.
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Affiliation(s)
- H Haider
- Institut fur Kognitionsforschung, Universitat der Bundeswehr, Hamburg, Germany
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Watzek G, Gross P, Haider H. [Position report on modern implantation from surgical viewpoint]. Niedersachs Zahnarztebl 1991; 26:348-54. [PMID: 1945767] [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: 12/29/2022]
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