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Semaphorin 3E/collapsin-5 inhibits growing retinal axons

EXPERIMENTAL CELL RESEARCH 2002年第1期279卷 52-61页

作者： Steinbach, K Volkmer, H Schlosshauer, B Univ Tubingen NMI Nat Wissensch & Med Inst D-72770 Reutlingen Germany

During development, the formation of neural networks is reflected by the oriented extension of neurites. Using retinal ganglion cells (RGCs) as a model, we identified the yet uncharacterized chick semaphorin Sema3E/collapsin-5 as a repulsive cue for outgrowing axons. Sema3E/collapsin-5 was highly regulated during retinal histogenesis, with peak expression during the period of intraretinal axon growth. Polymerase chain reaction analysis demonstrated Sema3E/collapsin-5 mRNA in retina layers, from which RGC axons are excluded. Neither isolated RGCs nor purified retinal Muller glia cells synthesized Sema3E/collapsin-5. Sema3E/ collapsin-5 receptor sites were visualized by alkaline phosphatase fusion proteins in the axon-rich optic fiber layer. Time-lapse video recording of chick in vitro cultures revealed a growth cone collapsing activity of recombinant Sema3E/collapsin-5. This effect was specific for RGCs, since dorsal root ganglia (DRG) neurons of the peripheral nervous system were not affected. Comparison with Sema3A/collapsin-1 displayed a reciprocal specificity, because Sema3A/collapsin-1 hampered exclusively DRG but not RGC growth cones. The collapsing effect was mediated by low cGMP levels, but not cAMP, as revealed by a set of agonists. In summary, the data suggest a possible role of chick Sema3E/collapsin-5 in restricting growth of retinal ganglion cell axons to the optic fiber layer. (C) 2002 Elsevier Science (USA).

关键词： cGMP chick ganglion cell dorsal root ganglia growth cone collapse guidance neuronal development retina time-lapse video recording

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Expression of Nogo protein by growing axons in the developing nervous system

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MOLECULAR BRAIN RESEARCH 2002年第2期104卷 111-119页

作者： Tozaki, H Kawasaki, T Takagi, Y Hirata, T Grad Univ Adv Studies Natl Inst Genet Div Brain Funct Mishima Shizuoka 4118540 Japan

We produced monoclonal antibody NG1 that strongly binds growing axons in the developing nervous system of mice. This antibody intensely labeled the growth cone of cultured neurons. Although these immunostaining patterns suggested the association of growing axons with the antigen recognized by this antibody, the antigen was identified as Nogo protein, an axonal repulsive factor isolated from the myelin. On the basis of this unexpected finding, we discuss the possible functions of Nogo in the developing nervous system. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： Nogo axon guidance regeneration monoclonal antibody

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Duplex ultrasound-guided femoropopliteal angioplasty: Initial and 12-month results from a case controlled study

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JOURNAL OF ENDOVASCULAR THERAPY 2002年第6期9卷 873-881页

作者： Ahmadi, R Ugurluoglu, A Schillinger, M Katzenschlager, R Sabeti, S Minar, E Univ Vienna Sch Med Vienna Gen Hosp Dept Angiol A-1090 Vienna Austria

Purpose: To evaluate initial technical success, procedural complications, and 12-month patency of duplex-guided angioplasty compared to conventional fluoroscopically-guided procedures. Methods: One hundred four patients (65 men;mean age 69 years) who underwent duplex-guided femoropopliteal angioplasty were compared to 104 patients undergoing fluoroscopically-guide procedures who were matched for age, sex, baseline ankle-brachial index (ABI), and length and grade of lesion. Patients were followed for 12 months, and restenosis was assessed by ABI and duplex sonography. Results: Technical success was achieved in 88 (84.6%) patients from the duplex-guided group and in 102 (98.1%) control patients (p=0.001). Periprocedural complications occurred in 12.5% (n=13) and 18.3% (n=19), respectively (p=0.4). Contrast-induced transient renal impairment was observed in 7 (6.7%) patients in the fluoroscopic group. One hundred (96.1%) patients in the duplex and 102 (98.1%) patients in the fluoroscopic group completed the 12-month follow-up. Restenosis was found in 35 (39.8%) patients of the duplex group and in 38 (37.2%) patients of the fluoroscopic group (p=0.8). Conclusions: Technical success of duplex-guided procedures was significantly lower compared to fluoroscopic angioplasty;complications and 12-month patency were similar with both techniques. Duplex-guided angioplasty may be a feasible alternative, particularly for patients at high risk for contrast-induced complications.

关键词： duplex ultrasound fluoroscopy guidance contrast agent restenosis

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Expression and role of roundabout-1 in embryonic Xenopus forebrain

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DEVELOPMENTAL DYNAMICS 2002年第1期225卷 22-34页

作者： Connor, RM Key, B Univ Queensland Dept Anat & Dev Biol Sch Biomed Sci Brisbane Qld 4072 Australia Univ Queensland Ctr Funct & Appl Gen Brisbane Qld 4072 Australia

The receptor Roundabout-1 (Robo1) and its ligand Slit are known to influence axon guidance and central nervous system (CNS) patterning in both vertebrate and nonvertebrate systems. Although Robo-Slit interactions mediate axon guidance in the Drosophila CNS, their role in establishing the early axon scaffold in the embryonic vertebrate brain remains unclear. We report here the identification and expression of a Xenopus Robo1 orthologue that is highly homologous to mammalian Robo1. By using overexpression studies and immunohistochemical and in situ hybridization techniques, we have investigated the role of Robo1 in the development of a subset of neurons and axon tracts in the Xenopus forebrain. Robo1 is expressed in forebrain nuclei and in neuroepithelial cells underlying the main axon tracts. Misexpression of Robo1 led to aberrant development of axon tracts as well as the ectopic differentiation of forebrain neurons. These results implicate Robo1 in both neuronal differentiation and axon guidance in embryonic vertebrate forebrain. (C) 2002 Wiley-Liss, Inc.

关键词： chemorepulsion neurogenesis axon guidance brain navigation

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CT fluoroscopy-assisted puncture of thoracic and abdominal masses: A randomized trial

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CLINICAL RADIOLOGY 2002年第3期57卷 188-192页

作者： Kirchner, J Kickuth, R Laufer, U Schilling, EM Adams, S Liermann, D Ruhr Univ Bochum Klinikum Kathol Marienhosp Herne Klin Diagnost Radiol & Nukl Med D-44625 Herne Germany

PURPOSE: We investigated the benefit of real-time guidance of interventional punctures by means of computed tomography fluoroscopy (CTF) compared with the conventional sequential acquisition guidance. MATERIAL AND METHODS: In a prospective randomized trial, 75 patients underwent either CTF-guided (group A, n = 50) or sequential CT-guided (group B, n = 25) punctures of thoracic (n = 29) or abdominal (n = 46) masses. CTF was performed on the CT machine (Somatom Plus 4 Power, Siemens Corp., Forchheim, Germany) equipped with the C.A.R.E. Vision application (tube voltage 120 kV, tube current 50 mA, rotational time 0.75 s, slice thickness 10 mm, 8 frames/s). RESULTS: The average procedure time showed a statistically significant difference between the two study groups (group A: 564 s, group B 795 s, P = 0.0032). The mean total mAs was 7089 mAs for the CTF and 4856 mAs for the sequential image-guided intervention, respectively. The sensitivity was 71% specificity 100% positive predictive value 100% and negative predictive value 60% for the CTF-guided puncture, and 68, 100, 100 and 50% for sequential CT, respectively. CONCLUSION: CTF guidance realizes a time-saving but increases the radiation exposure dosage. (C) 2002 The Royal College of Radiologists.

关键词： computed tomography intervention guidance real-time imaging CT fluoroscopy

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Simultaneous localization and map building using natural features and absolute information

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ROBOTICS AND AUTONOMOUS SYSTEMS 2002年第2-3期40卷 79-90页

作者： Guivant, JE Masson, FR Nebot, EM Univ Sydney Dept Mech & Mechatron Engn Australian Ctr Field Robot Sydney NSW 2006 Australia Univ Sydney Ctr Min Technol & Equipment Sydney NSW 2006 Australia

This work presents real time implementation algorithms of Simultaneous Localization and Map Building (SLAM) with emphasis to outdoor land vehicle applications in large environments. It presents the problematic of outdoors navigation in areas with combination of feature and featureless regions. The aspect of feature detection and validation is investigated to reliably detect the predominant features in the environment. Aided SLAM algorithms are presented that incorporate absolute information in a consistent manner. The SLAM implementation uses the compressed filter algorithm to maintain the map with a cost proportional to number of landmarks in the local area. The information gathered in the local area requires a full SLAM update when the vehicle leaves the local area. Algorithms to reduce the full update computational cost are also presented. Finally, experimental results obtained with a standard vehicle running in unstructured outdoor environment are presented. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： SLAM outdoors navigation guidance mobile robots

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Guidelines and legal requirements which inform role expansion in radiography

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Radiography 2002年第2期8卷 71-78页

作者： White, P. Mckay, J.C. Department of Optometry and Radiography Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

Purpose: Role expansion in radiography is linked to ethico-legal responsibilities and accountability. This paper clarifies the legal requirements, outlines professional guidelines, and suggests that role developments require new rules and standards. Methods: A thorough review of the literature was used to collect information on role expansion and related topics, such as Continuous Professional Development (CPD) and skills mix. Emphasis was placed on case law and professional guidelines. Results: Radiographers who develop their roles must continue to provide a high quality service and demonstrate high level competencies, skills and knowledge. When deciding who should provide the service, the ultimate decision should be based on client benefit. Radiographers who expand their role will be gauged against specialists in that field, e.g. medical professionals, so radiographers must be confident in their own abilities and competent to perform such tasks. If a radiographer claims to be a specialist, the standard of care is that of the reasonable specialist and not that of the general radiographer. In legal terms, a patient is entitled to a greater standard of care from a specialist than from an ordinary practitioner and radiographers must meet that standard. Conclusions: Role expansion in radiography has associated legal responsibilities and radiographers are accountable for acts or omissions arising out of practice. Guidelines should be established which ensure that radiographers have skills and knowledge on a par with specialists in their area of practice so as to maintain the maximum benefit to the client. © 2002 The College of Radiographers. Published by Elsevier Science Ltd. All rights reserved.

关键词： Accountability guidance Responsibility Role development

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Simultaneous localization and map building using natural features and absolute information

Simultaneous localization and map building using natural fea...

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6th International Conference on Intelligent Autonomous Systems (IAS-6)

关键词： SLAM outdoors navigation guidance mobile robots

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Regulatory issues for health-related quality of life - PhRMA Health Outcomes Committee Workshop, 1999

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Value in Health 2002年第1期5卷 14-25页

作者： Santanello, N.C. Baker, E. Cappelleri, J.C. Copley-Merriman, K. DeMarinis, R. Gagnon, J.P. Hsuan, A. Jackson, J. Mahmoud, R. Miller, D. Morgan, M. Osterhaus, J. Tilson, H. Willke, R. Merck Research Laboratories West Point PA United States Pfizer Inc. New York NY United States Pfizer Inc. Global Research and Development Groton CT United States Wyeth-Ayerst Research St. Davids PA United States Aventis Pharmaceuticals Inc. Bridgewater NJ United States Janssen Research Foundation Titusville NJ United States Bristol-Myers Squibb Princeton NJ United States Janssen Pharmaceutica Titusville NJ United States GlaxoSmithKline Greenford United Kingdom Eli Lilly and Company Indianapolis IN United States Wasatch Health Outcomes Park City UT United States Pharmacia Corp. Peapack NJ United States

Introduction: Health-related quality-of-life (HRQL) can be defined as the impact of disease and treatment across the physical, psychological, social and somatic domains of functioning and well-being. Health-related quality-of-life measures are included in clinical trials of drug treatment to assess the impact of therapy on the patient's functioning. HRQL guidance could allow for use of this data in drug labeling and promotion. Objectives: The aim of our study was to provide recommendations with respect to regulatory issues important to the development of guidelines for HRQL research. Methods: The HRQL workshop was planned jointly by members of the Pharmaceutical Research and Manufacturers of America Health Outcomes Committee and the Division of Drug Marketing, Advertising, and Communications of the Food and Drug Administration. The workshop was limited to six regulatory issues related to HRQL research in clinical trials of pharmaceutical therapies. These six issues were: instrument selection and validation, study design, data analysis, HRQL and safety, clinical meaning, and promotional use. Before the meeting, a consensus was reached that HRQL does not measure, nor should it be used to measure, safety. Therefore, five work groups discussed HRQL issues and made recommendations. Results: Overall, the workshop recommended that HRQL measures be treated as any other clinical end point. The workshop recognized that research in HRQL methods is ongoing and that any guidance should be flexible to allow for changes in this developing research area. Conclusions: HRQL provides a patient perspective on the impact of disease and therapy on patients' daily life and functioning. Including HRQL information in promotion could be beneficial to decision making on the use of therapies. HRQL is a measure of effectiveness, not safety, and should be treated as any other clinical end point.

关键词： guidance Outcomes research Quality-of-life research Regulatory

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Economic evaluations relating to diabetes: A descriptive review and their compliance with guidance

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Value in Health 2000年第SUPPL. 1期3卷 7-14页

作者： Oliver, Adam Pritchard, Clive Office of Health Economics London United Kingdom Office of Health Economics 12 Whitehall London SW1A 2DY United Kingdom

From a search of the Health Economics Evaluations Database (HEED), 301 studies relating to diabetes-related interventions were identified. Of these, 223 studies contained some original data, i.e., were applied studies. Over the 1990s, the number of studies undertaken in this area appears to be increasing year on year, and more of the studies are applicable to the USA than to all other countries combined. Most studies are peer reviewed, the main type of analysis is cost-consequence, and the interventions most often assessed are pharmaceutical and care services. Both the public and the private sectors sponsor many of these studies. However, only a fraction of these studies appear to accord with guidance for good economic evaluation. For example, when the search criteria were tightened to capture only those studies that consider both outcomes and costs, 173 studies were identified. Narrowing the search criteria to capture only those studies that were based on randomized controlled trial (RCT) or modeling data - The methods recommended by the US Panel and the National Institute of Clinical Excellence (NICE) - Reduced the sample to 56 studies. With specific focus on those studies that evaluated pharmaceuticals, only the modeling approach appeared to show any compliance, at all with another key recommendation of the existing guidance on methods;that of using outcome measures that are applicable to a long-term time horizon. Though modeling does offer certain advantages over RCTs (for example, a larger range of comparators can be more readily incorporated, long-term outcome measures can be more easily and inexpensively estimated), modeling results have less internal validity. Also, modeling in itself relies on good RCT data. Therefore, the results of economic evaluations should be interpreted, with care, irrespective of whether they are principally based on RCT or model-based methods.

关键词： Descriptive review Diabetes Economic evaluation guidance

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