1
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Nemeth B, Smeets M, Pedersen AB, Kristiansen EB, Nelissen R, Whyte M, Roberts L, de Lusignan S, le Cessie S, Cannegieter S, Arya R. Development and validation of a clinical prediction model for 90-day venous thromboembolism risk following total hip and total knee arthroplasty: a multinational study. J Thromb Haemost 2024; 22:238-248. [PMID: 38030547 DOI: 10.1016/j.jtha.2023.09.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/07/2023] [Accepted: 09/07/2023] [Indexed: 12/01/2023]
Abstract
BACKGROUND The risk of venous thromboembolism (VTE) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) is 1.0% to 1.5%, despite uniform thromboprophylaxis. OBJECTIVES To develop and validate a prediction model for 90-day VTE risk. METHODS A multinational cohort study was performed. For model development, records were used from the Oxford Royal College of General Practitioners Research and Surveillance Centre linked to Hospital Episode Statistics and Office of National Statistics UK routine data. For external validation, data were used from the Danish Hip and Knee Arthroplasty Registry, the National Patient Registry, and the National Prescription Registry. Binary multivariable logistic regression techniques were used for development. RESULTS In the UK data set, 64 032 THA/TKA procedures were performed and 1.4% developed VTE. The prediction model consisted of age, body mass index, sex, cystitis within 1 year before surgery, history of phlebitis, history of VTE, presence of varicose veins, presence of asthma, history of transient ischemic attack, history of myocardial infarction, presence of hypertension and THA or TKA. The area under the curve of the model was 0.65 (95% CI, 0.63-0.67). Furthermore, 36 169 procedures were performed in the Danish cohort, of whom 1.0% developed VTE. Here, the area under the curve was 0.64 (95% CI, 0.61-0.67). The calibration slope was 0.92 in the validation study and 1.00 in the development study. CONCLUSION This clinical prediction model for 90-day VTE risk following THA and TKA performed well in both development and validation data. This model can be used to estimate an individual's risk for VTE following THA/TKA.
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Affiliation(s)
- Banne Nemeth
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands; Department of Orthopaedic Surgery, Leiden University Medical Center, Leiden, The Netherlands.
| | - Mark Smeets
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands. https://twitter.com/MarkSmeets4
| | - Alma Becic Pedersen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark. https://twitter.com/AlmaBPedersen
| | - Eskild Bendix Kristiansen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Rob Nelissen
- Department of Orthopaedic Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Martin Whyte
- Department of Clinical and Experimental Medicine, University of Surrey, Guildford, UK. https://twitter.com/mbwhyte1
| | - Lara Roberts
- King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, London UK. https://twitter.com/LaraNRoberts1
| | - Simon de Lusignan
- Department of Clinical and Experimental Medicine, University of Surrey, Guildford, UK; Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK. https://twitter.com/lusignan_s
| | - Saskia le Cessie
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands; Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands
| | - Suzanne Cannegieter
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands; Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands. https://twitter.com/s_cannegieter
| | - Roopen Arya
- King's Thrombosis Centre, King's College Hospital NHS Foundation Trust, London UK. https://twitter.com/AryaRoopen
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2
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Smeets M, Koohbor B, Youssef G. Quasi-Static Mechanical Response of Density-Graded Polyurea Elastomeric Foams. ACS Appl Polym Mater 2023; 5:2840-2851. [PMID: 37090421 PMCID: PMC10112387 DOI: 10.1021/acsapm.3c00062] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/21/2023] [Indexed: 05/03/2023]
Abstract
Density gradation of foam structures has been investigated and found to be a practical approach to improve the mechanical efficacy of protective padding in several applications based on nature-based evidence of effectiveness. This research aims to disclose a discrete gradation approach without adhesives by relying on the properties of the frothed foam slurry to bond and penetrate through previously cured foam sheets naturally. As confirmed by electron microscopy observations, bilayer- and trilayer-graded elastomeric polyurea foam sheets were fabricated, resulting in seamless interfaces. The mechanical performance of seamless, graded foam samples was compared with monolayer, mono-density benchmark foam, considered the industry standard for impact mitigation. All foam samples were submitted to compressive loading at a quasi-static rate, reporting key performance indicators (KPIs) such as specific energy absorption, efficiency, and ideality. Polyurea foams, irrespective of gradation and interface type, outperformed benchmark foam in several KPIs despite the drastic difference in the effective or average density. The average compressive stress-strain curves were fitted into empirical constitutive models to reveal critical insights into the elastic, plateau, and densification behaviors of the tested foam configuration. The novelty of these outcomes includes (1) a fabrication approach to adhesive-free density-graded foam structures, (2) implementation of a diverse set of KPIs to assess the mechanical efficacy of foams, and (3) elucidation of the superiority of polyurea foam-based lightweight protective paddings. Future research will focus on assessing the dynamic performance of these graded foam structures under impact loading conditions at a wide range of velocities.
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Affiliation(s)
- Mark Smeets
- Experimental
Mechanics Laboratory, Mechanical Engineering Department, San Diego State University, 5500 Campanile Drive, San Diego, California 921821, United States
| | - Behrad Koohbor
- Department
of Mechanical Engineering, Rowan University, 201 Mullica Hill Road, Glassboro, New Jersey 08028, United States
| | - George Youssef
- Experimental
Mechanics Laboratory, Mechanical Engineering Department, San Diego State University, 5500 Campanile Drive, San Diego, California 921821, United States
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3
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Baldewijns K, Vandenhoudt H, Nijst P, Vercammen J, Van Laethem M, Haumont L, Vandepoel I, Moldenaers I, Brunner La-Rocca HP, Smeets M. enhancing primary Care: development of a Training for primary care nurses in heart failure Education. Eur J Cardiovasc Nurs 2022. [DOI: 10.1093/eurjcn/zvac060.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): King Baudouin Foundation Belgium
Background, Self-care in Heart Failure (HF) is important to prevent rehospitalisation and to improve Quality of Life (QoL).1, 2 Therefore, it is necessary that HF-patients receive continuous education and self-care support, both in the hospital as at home.3 In Belgium, multidisciplinary (Mdisc-) HF-programmes are not yet broadly implemented, nor does a national HF-DMP exists. Specialist HF-nurses are not readily available and GPs report that they do not have time for patient education . 4,5 GPs identified trained primary care nurses (PCN) as their preferred partner to take on patient education and self-care support.5 However, currently, these nurses are not trained to take on this role.5
Purpose
To develop an evidence-based HF-educator training for primary care nurses.
Methods
The training was developed in 10 consecutive steps:
Step 1, a working group with representatives of Belgian HF-cardiologists, HF-nurses, PCN and the nursing department of a university of applied sciences was established.
Step 2, in preparation of this working group, M., a PCN and primary care HF-nurse, reviewed the curriculum of the specialist HF-nurse training to identify the (non-) relevant topics for PCN training. She presented her findings during working group 1 in which we decided to consult the primary health care professionals.
Step 3, one group interview with PCN, one interview with a GP and a diabetes educator took place. A short interview guide was developed. The main conclusions were that PCN have limited awareness for HF, it should be a short in time training, psychosocial aspects are very important, PCN should be able to detect signs and symptoms of HF, a basic module on HF must be included.
Step 4, presentation of these results to the working group.
Step 5, development of an organisational framework
Step 6, a subgroup consisting of one specialist HF-nurse, one HF-educator- and HF-nurse in primary care developed a programme based on the results of the interviews, the HFA-curriculum and the organisational framework.
Step 7, this programme was presented to and approved by the working group
Step 8, representatives of the university of applied sciences will implement the programme as part of their life-long learning programme.
Step 9 and 10: pilot and evaluation.
Results
The PCN HF-educator education will take 20h in 3 consecutive weeks. Participants will receive a theoretical introduction in HF followed by intensive practical training on patient-education, self-care and psychosocial support. In March 2022 the first pilot will take place.
Conclusions
Continuous education is important to support patients in their self-care and self-management. Therefore, it is necessary to train and support primary health care professionals in order to prepare them for this tasks. We presented a co-creative methodology to develop and implement a training for health care professionals.
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Affiliation(s)
| | - H Vandenhoudt
- Thomas More University of applied sciences , Health Care Department , Turnhout , Belgium
| | - P Nijst
- Hospital Oost-Limburg (ZOL) , Genk , Belgium
| | - J Vercammen
- Hospital Oost-Limburg (ZOL) , Genk , Belgium
| | - M Van Laethem
- Wit-Gele Kruis, Afdeling Oost-Vlaanderen , Dendermonde , Belgium
| | - L Haumont
- University College Leuven Limburg, Nursing Department , Genk , Belgium
| | - I Vandepoel
- University College Leuven Limburg, Nursing Department , Leuven , Belgium
| | - I Moldenaers
- University College Leuven Limburg, Nursing Department , Genk , Belgium
| | - H P Brunner La-Rocca
- Maastricht University Medical Centre (MUMC), Department of Cardiology , Maastricht , Netherlands (The)
| | - M Smeets
- University of Leuven, Academic Centre for General Practice , Leuven , Belgium
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4
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Baldewijns K, Smeets M, Vandenhoudt H. Learning Health Care Network Heart Failure: towards a better Heart Failure care in Belgium. Eur J Cardiovasc Nurs 2021. [DOI: 10.1093/eurjcn/zvab060.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Koning Boudewijn Stichting, Fonds Dr. Daniel De Konick
Background
The best HF-care is provided in a seamless system that includes both community- and hospital care to avoid hospital readmission. Essential elements to included in such a system are a.o. discharge planning, follow-up, multidisciplinary patient education, teamwork incl. shared professional education, medication optimisation and implementation of care pathways across settings.
Purpose
To facilitate seamless HF-care in Belgium trough capacity building in primary care and improved communication between primary and specialist care.
Methods
HeartsConnect, a Learning Health care Network Heart Failure (LHCN-HF) was established and unites eight regional integrated care projects in Flanders, the Flemish speaking region of Belgium. This LHCN-HF organizes regular symposia on relevant topics for their members. Furthermore, materials to facilitate professional and patient education are being developed. To scale-up integrated care the LHCN-HF works together with several stakeholders. In addition, the process and results of the participating projects will be evaluated.
Results
Four symposia have taken place since the start of the LHCN. The discussed topics were project evaluation and data collection, the roles in a multidisciplinary team, data sharing and best practises. Narrated PowerPoints considering HF-management for GP’s, pharmacists and physiotherapists are being developed in collaboration with their professional associations. To scale-up integrated HF-care, the LHCN-HF works in close collaboration with the Belgian Working Group on Heart Failure and the Flemish Hospital Network. Together with national organizations the LHCN strives for the recognition of HF-nurses, standardized discharge planning, reimbursement of NT-pro-BNP and HF-education and the training of primary care nurses (PCN) in terms of HF-education, aligned with the existing initiatives of HF-nurse education.
Conclusion
At this moment a seamless system of HF-care is not yet in place in Belgium. However, the LHCN-HF together with several HF-stakeholders aims to bridge existing gaps between primary- and specialist HF-care.
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Affiliation(s)
| | - M Smeets
- University of Leuven, Academic Centre for General Practice , Leuven, Belgium
| | - H Vandenhoudt
- Thomas More University of applied sciences , Health Care Department , Turnhout, Belgium
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5
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Verhelst PJ, Matthews H, Verstraete L, Van der Cruyssen F, Mulier D, Croonenborghs TM, Da Costa O, Smeets M, Fieuws S, Shaheen E, Jacobs R, Claes P, Politis C, Peeters H. Automatic 3D dense phenotyping provides reliable and accurate shape quantification of the human mandible. Sci Rep 2021; 11:8532. [PMID: 33879838 PMCID: PMC8058070 DOI: 10.1038/s41598-021-88095-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/05/2021] [Indexed: 11/12/2022] Open
Abstract
Automatic craniomaxillofacial (CMF) three dimensional (3D) dense phenotyping promises quantification of the complete CMF shape compared to the limiting use of sparse landmarks in classical phenotyping. This study assesses the accuracy and reliability of this new approach on the human mandible. Classic and automatic phenotyping techniques were applied on 30 unaltered and 20 operated human mandibles. Seven observers indicated 26 anatomical landmarks on each mandible three times. All mandibles were subjected to three rounds of automatic phenotyping using Meshmonk. The toolbox performed non-rigid surface registration of a template mandibular mesh consisting of 17,415 quasi landmarks on each target mandible and the quasi landmarks corresponding to the 26 anatomical locations of interest were identified. Repeated-measures reliability was assessed using root mean square (RMS) distances of repeated landmark indications to their centroid. Automatic phenotyping showed very low RMS distances confirming excellent repeated-measures reliability. The average Euclidean distance between manual and corresponding automatic landmarks was 1.40 mm for the unaltered and 1.76 mm for the operated sample. Centroid sizes from the automatic and manual shape configurations were highly similar with intraclass correlation coefficients (ICC) of > 0.99. Reproducibility coefficients for centroid size were < 2 mm, accounting for < 1% of the total variability of the centroid size of the mandibles in this sample. ICC’s for the multivariate set of 325 interlandmark distances were all > 0.90 indicating again high similarity between shapes quantified by classic or automatic phenotyping. Combined, these findings established high accuracy and repeated-measures reliability of the automatic approach. 3D dense CMF phenotyping of the human mandible using the Meshmonk toolbox introduces a novel improvement in quantifying CMF shape.
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Affiliation(s)
- Pieter-Jan Verhelst
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium. .,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium.
| | - H Matthews
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Medical Imaging Research Center, University Hospitals Leuven, Leuven, Belgium.,Facial Sciences Research Group, Murdoch Children's Research Institute, Parkville, Australia
| | - L Verstraete
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - F Van der Cruyssen
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - D Mulier
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - T M Croonenborghs
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - O Da Costa
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - M Smeets
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - S Fieuws
- Leuven Biostatistics and Statistical Bioinformatics Centre, KU Leuven, Leuven, Belgium
| | - E Shaheen
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - R Jacobs
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium.,Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - P Claes
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Medical Imaging Research Center, University Hospitals Leuven, Leuven, Belgium.,Facial Sciences Research Group, Murdoch Children's Research Institute, Parkville, Australia.,Department of Electrical Engineering, ESAT/PSI, KU Leuven, Leuven, Belgium
| | - C Politis
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - H Peeters
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Department of Human Genetics, University Hospitals Leuven, Leuven, Belgium
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6
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Politis C, Kalantary S, Van Snick E, Smeets M, Politis C. Lingua villosa nigra in a patient with a Zenker's diverticulum. Oral and Maxillofacial Surgery Cases 2020. [DOI: 10.1016/j.omsc.2020.100186] [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: 11/26/2022] Open
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7
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Tian L, Oikonomopoulos A, Liu C, Kitani T, Shrestha R, Chen CL, Ong SG, Smeets M, Karakikes I, Sayed N, Wu JC. Molecular Signatures of Beneficial Class Effects of Statins on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Circulation 2020; 141:1208-1210. [PMID: 32250699 DOI: 10.1161/circulationaha.118.035906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Lei Tian
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Medicine, Division of Cardiology (L.T., C.L., T.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Angelos Oikonomopoulos
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Chun Liu
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Medicine, Division of Cardiology (L.T., C.L., T.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Tomoya Kitani
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Medicine, Division of Cardiology (L.T., C.L., T.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Rajani Shrestha
- Department of Radiology (R.S., J.C.W.), Stanford University School of Medicine, CA
| | - Christopher L Chen
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Sang-Ging Ong
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Mark Smeets
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Ioannis Karakikes
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Nazish Sayed
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Medicine, Division of Cardiology (L.T., C.L., T.K., N.S., J.C.W.), Stanford University School of Medicine, CA
| | - Joseph C Wu
- Stanford Cardiovascular Institute (L.T., A.O., C.L., T.K., C.L.C., S.-G.O., M.S., I.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Medicine, Division of Cardiology (L.T., C.L., T.K., N.S., J.C.W.), Stanford University School of Medicine, CA.,Department of Radiology (R.S., J.C.W.), Stanford University School of Medicine, CA
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8
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Smeets M, Bittkau K, Lentz F, Richter A, Ding K, Carius R, Rau U, Paetzold UW. Post passivation light trapping back contacts for silicon heterojunction solar cells. Nanoscale 2016; 8:18726-18733. [PMID: 27787533 DOI: 10.1039/c6nr04960e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Light trapping in crystalline silicon (c-Si) solar cells is an essential building block for high efficiency solar cells targeting low material consumption and low costs. In this study, we present the successful implementation of highly efficient light-trapping back contacts, subsequent to the passivation of Si heterojunction solar cells. The back contacts are realized by texturing an amorphous silicon layer with a refractive index close to the one of crystalline silicon at the back side of the silicon wafer. As a result, decoupling of optically active and electrically active layers is introduced. In the long run, the presented concept has the potential to improve light trapping in monolithic Si multijunction solar cells as well as solar cell configurations where texturing of the Si absorber surfaces usually results in a deterioration of the electrical properties. As part of this study, different light-trapping textures were applied to prototype silicon heterojunction solar cells. The best path length enhancement factors, at high passivation quality, were obtained with light-trapping textures based on randomly distributed craters. Comparing a planar reference solar cell with an absorber thickness of 280 μm and additional anti-reflection coating, the short-circuit current density (JSC) improves for a similar solar cell with light-trapping back contact. Due to the light trapping back contact, the JSC is enhanced around 1.8 mA cm-2 to 38.5 mA cm-2 due to light trapping in the wavelength range between 1000 nm and 1150 nm.
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Affiliation(s)
- M Smeets
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - K Bittkau
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - F Lentz
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - A Richter
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - K Ding
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - R Carius
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - U Rau
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany.
| | - U W Paetzold
- Forschungszentrum Jülich GmbH IEK-5 Photovoltaics, Germany. and IMEC - Partner in Solliance, Kappeldreef 75, Leuven, B-3001, Belgium and Institute of Microstructure Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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9
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García de Lorenzo A, Alvarez J, Celaya S, García Cofrades M, García Luna PP, García Peris P, León-Sanz M, Jiménez CP, Olveira G, Smeets M. [The Spanish Society of Parenteral and Enteral Nutrition (SENPE) and its relation with healthcare authorities]. NUTR HOSP 2011; 26:251-3. [PMID: 21666959 DOI: 10.1590/s0212-16112011000200002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 01/25/2011] [Indexed: 11/21/2022] Open
Abstract
It has been well documented in medical literature that hyponutrition is a common issue at all healthcare levels, from primary to specialized health care, as well as geriatric healthcare facilities. This problem is not limited to countries with scarce economic resources or limited social development; it is also a universal issue in Europe. Hyponutrition increases the rates of morbidity, mortality, hospital admissions, and hospital stay. These higher figures also represent a higher use of healthcare resources. In spite of this, hyponutrition may often go undetected and the patient may not receive the necessary treatment. This problem requires the cooperation of multiple agents such as the Governments, the healthcare professionals, and the citizens themselves. The VIII Discussion Forum concludes on the need to establish a clear-cut plant for action (similar to the European Alliance for Health Nutrition) and the creation of a platform (coalition) encompassing the voices of healthcare professionals associations, institutions, professional colleges, patients associations, the pharmaceutical companies, and insurance companies. The goals of this platform will be to inform about the extent of this issue, to identity and promote leaders that will convey the aims of this initiative to regional and national healthcare authorities, to present solutions and to collaborate in their implementation, and finally to assess/control the actions taken.
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10
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Opiekun RE, Smeets M, Sulewski M, Rogers R, Prasad N, Vedula U, Dalton P. Assessment of ocular and nasal irritation in asthmatics resulting from fragrance exposure. Clin Exp Allergy 2003; 33:1256-65. [PMID: 12956748 DOI: 10.1046/j.1365-2222.2003.01753.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Many asthmatics report worsening of symptoms following exposure to odours and sensory irritants commonly found in household and cosmetic products. Despite this, little evidence exists to confirm the degree to which such subjective reports are correlated with localized, objective changes in the upper or lower airways following a fragranced product exposure. OBJECTIVE Subjective symptom reports were compared to objective measures in mild asthmatics, moderate asthmatics and non-asthmatics following exposure to one of two fragranced household aerosol mixtures and a clean air control condition to determine if asthmatics reported greater subjective symptoms of nasal congestion or exhibited objective measures of elevated ocular irritation and nasal congestion following exposure than did healthy controls. METHODS Measures of nasal mucosal swelling, using acoustic rhinometry, and photographic assessments of ocular hyperemia, using macro-photography, were taken before exposure, immediately after an initial 5-min exposure and again following a 30-min exposure to either of two, fragranced aerosol products and a clean air control. Self-reports of nasal patency at each time-point were also obtained. RESULTS Although moderate asthmatics tended to report more nasal congestion following fragranced product exposure than did non-asthmatics, no exposure-related changes in ocular redness or nasal mucosal swelling were observed among the three groups. Spirometry readings also failed to show evidence of any exposure-related changes in pulmonary function. CONCLUSION Despite claims that exposure to fragranced products may trigger ocular and respiratory symptoms among asthmatics, we found no evidence that 30 min of exposure to one of two fragranced aerosols elicited objective adverse effects in the ocular or nasal mucosa of mild and moderate asthmatics. While physiological mechanisms of fragrance impact may yet be responsible for some of the adverse reports among asthmatics following fragrance exposure, such reports may also reflect a non-physiological locus of symptom perception triggered by other sensory cues.
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Affiliation(s)
- R E Opiekun
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA.
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11
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Smeets M, Raymakers R, Muus P, Vierwinden G, Linssen P, Masereeuw R, de Witte T. Cyclosporin increases cellular idarubicin and idarubicinol concentrations in relapsed or refractory AML mainly due to reduced systemic clearance. Leukemia 2001; 15:80-8. [PMID: 11243404 DOI: 10.1038/sj.leu.2401996] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [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: 11/08/2022]
Abstract
The feasibility of adding both the multidrug resistance modulator cyclosporin (CsA) and granulocyte colony-stimulating factor (G-CSF) to a standard salvage regimen of idarubicin (IDA) and cytarabine was evaluated in patients with resistant or relapsed acute myeloid leukemia and myelodysplastic syndrome. Three patients received IDA 12 mg/m2/day, the next four patients 9 mg/m2/day. The dose of CsA was 16 mg/kg/day. Six patients showed Pgp expression and none MRP1 expression. Grade III or IV toxicity (CTC-NCIC criteria) was registered in six patients for gastrointestinal, two patients for cardiovascular and one patient for neurological complications. Three patients died in hypoplasia and three patients showed leukemic regrowth. Three control patients were treated with IDA 12 mg/m2/day and cytarabine, but no CsA and G-CSF. The plasma IDA and idarubicinol (ida-ol) area under the curve's of patients treated with IDA 12 mg/m2 plus CsA were higher (P< 0.05) than in controls. Cellular IDA concentrations were almost similar, but cellular ida-ol concentrations were significantly higher (P < 0.05) in the presence of CsA than in controls. We conclude that the toxicity either with IDA 12 or 9 mg/m2/day was too high. The modulating effect of CsA was mainly based on changes in plasma kinetics of IDA and ida-ol, although ida-ol cellular clearance was delayed in the presence of CsA.
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Affiliation(s)
- M Smeets
- Department of Hematology, University Medical Center Nijmegen, The Netherlands
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12
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de Vries TJ, Smeets M, de Graaf R, Hou-Jensen K, Bröcker EB, Renard N, Eggermont AM, van Muijen GN, Ruiter DJ. Expression of gp100, MART-1, tyrosinase, and S100 in paraffin-embedded primary melanomas and locoregional, lymph node, and visceral metastases: implications for diagnosis and immunotherapy. A study conducted by the EORTC Melanoma Cooperative Group. J Pathol 2001; 193:13-20. [PMID: 11169510 DOI: 10.1002/1096-9896(2000)9999:9999<::aid-path729>3.0.co;2-d] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [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: 11/11/2022]
Abstract
With the recent availability of novel antibodies against melanoma antigens tyrosinase and MART-1, it is important to validate their usefulness in pathology practice and in screening patients for immunotherapy treatment. In the present study conducted by the Melanoma Cooperative Group of the European Organization for Research and Treatment of Cancer (EORTC-MCG), immunohistochemical staining for gp100 (antibodies NKI-beteb and HMB-45), MART-1 (A103), tyrosinase (T311), and S100 (S100) was compared on formalin-fixed and paraffin-embedded tumour lesions from 80 patients with 130 malignant melanoma lesions, comprising 44 primary tumours, 18 locoregional metastases, 41 lymph node metastases, and 27 visceral metastases from the lung, liver, and brain. A score between 0 and 5 was allocated to each immunohistochemically stained section. These scores were evaluated in a statistical analysis. S100 was by far the most sensitive marker in all four types of lesions tested. Apart from a significantly better performance for T311 in primary melanomas compared with HMB-45, no significant differences were observed between the four remaining antigens tested. Three settings were next investigated to determine whether the expression of melanoma antigens decreases with tumour progression. First, within the primary melanomas, only NKI-beteb and A103 staining showed a nearly significant negative correlation with Clark's level of invasion and a similar tendency was observed for these antibodies with Breslow thickness. Second, when comparing primary melanoma-metastasis pairs from the same patient, lymph node metastases showed less staining with NKI-beteb, HMB-45, A103, and T311, at a level near significance. This difference was not significant when comparing the primary tumour with visceral metastases, probably due to the lower numbers of pairs. Third, regarding tumour progression from primary melanoma to locoregional, to lymph node, to visceral metastasis, a significant decrease with progression was found only for T311. The apparently stable expression of most of the melanoma antigens, and the small contribution of decreased expression in melanoma tumour progression, supports the rationale for immunotherapy based on the melanoma immunogens gp100, MART-1, and tyrosinase.
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Affiliation(s)
- T J de Vries
- Department of Pathology, UMC St Radboud, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
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13
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Abstract
Remission induction therapy fails in 20-30% of the patients with acute myeloid leukemia (AML) despite dose intensification and the use of new and more effective drugs. Primary and acquired drug resistance, metabolic or kinetic are a fundamental problem. Expression of the P-glycoprotein in AML is correlated with therapeutic outcome. Randomized clinical studies with Pgp modulators are currently on-going. Ara-C and anthracyclines, are preferentially cytotoxic to proliferating cells. Proliferation induction of leukemia blasts with growth factors in vitro resulted in an increased toxicity of Ara-C and anthracyclines. Normal hematopoietic blast cells with a high Pgp expression are noncycling and less sensitive to anthracyclines, in contrast to the more proliferating cells with a low Pgp expression. Proliferation induction by growth factors results in a down regulation of Pgp expression. Priming of leukemic cells with growth factors in vivo might be promising and randomized clinical studies are warranted.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- Antibiotics, Antineoplastic/therapeutic use
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Colony-Stimulating Factors/physiology
- Colony-Stimulating Factors/therapeutic use
- Cytarabine/therapeutic use
- Drug Resistance, Multiple
- Gene Expression Regulation, Neoplastic
- Genes, MDR
- Humans
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/genetics
- Remission Induction
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Affiliation(s)
- M Smeets
- University Hospital St. Radboud, Nijmegen, The Netherlands
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14
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de Haan CA, Smeets M, Vernooij F, Vennema H, Rottier PJ. Mapping of the coronavirus membrane protein domains involved in interaction with the spike protein. J Virol 1999; 73:7441-52. [PMID: 10438834 PMCID: PMC104271 DOI: 10.1128/jvi.73.9.7441-7452.1999] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/1999] [Accepted: 06/03/1999] [Indexed: 11/20/2022] Open
Abstract
The coronavirus membrane (M) protein is the key player in virion assembly. One of its functions is to mediate the incorporation of the spikes into the viral envelope. Heterotypic interactions between M and the spike (S) protein can be demonstrated by coimmunoprecipitation and by immunofluorescence colocalization, after coexpression of their genes in eukaryotic cells. Using these assays in a mutagenetic approach, we have mapped the domains in the M protein that are involved in complex formation between M and S. It appeared that the 25-residue luminally exposed amino-terminal domain of the M protein is not important for M-S interaction. A 15-residue deletion, the insertion of a His tag, and replacement of the ectodomain by that of another coronavirus M protein did not affect the ability of the M protein to associate with the S protein. However, complex formation was sensitive to changes in the transmembrane domains of this triple-spanning protein. Deletion of either the first two or the last two transmembrane domains, known not to affect the topology of the protein, led to a considerable decrease in complex formation, but association was not completely abrogated. Various effects of changes in the part of the M protein that is located at the cytoplasmic face of the membrane were observed. Deletions of the extreme carboxy-terminal tail appeared not to interfere with M-S complex formation. However, deletions in the amphipathic domain severely affected M-S interaction. Interestingly, changes in the amino-terminal and extreme carboxy-terminal domains of M, which did not disrupt the interaction with S, are known to be fatal to the ability of the protein to engage in virus particle formation (C. A. M. de Haan, L. Kuo, P. S. Masters, H. Vennema, and P. J. M. Rottier, J. Virol. 72:6838-6850, 1998). Apparently, the structural requirements of the M protein for virus particle assembly differ from the requirements for the formation of M-S complexes.
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Affiliation(s)
- C A de Haan
- Institute of Virology, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Institute of Biomembranes, Utrecht University, Utrecht, The Netherlands
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15
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Niculescu AB, Chen X, Smeets M, Hengst L, Prives C, Reed SI. Effects of p21(Cip1/Waf1) at both the G1/S and the G2/M cell cycle transitions: pRb is a critical determinant in blocking DNA replication and in preventing endoreduplication. Mol Cell Biol 1998; 18:629-43. [PMID: 9418909 PMCID: PMC121530 DOI: 10.1128/mcb.18.1.629] [Citation(s) in RCA: 562] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
It has been proposed that the functions of the cyclin-dependent kinase inhibitors p21(Cip1/Waf1) and p27Kip1 are limited to cell cycle control at the G1/S-phase transition and in the maintenance of cellular quiescence. To test the validity of this hypothesis, p21 was expressed in a diverse panel of cell lines, thus isolating the effects of p21 activity from the pleiotropic effects of upstream signaling pathways that normally induce p21 expression. The data show that at physiological levels of accumulation, p21, in addition to its role in negatively regulating the G1/S transition, contributes to regulation of the G2/M transition. Both G1- and G2-arrested cells were observed in all cell types, with different preponderances. Preponderant G1 arrest in response to p21 expression correlated with the presence of functional pRb. G2 arrest was more prominent in pRb-negative cells. The arrest distribution did not correlate with the p53 status, and proliferating-cell nuclear antigen (PCNA) binding activity of p21 did not appear to be involved, since p27, which lacks a PCNA binding domain, produced similar arrest distributions [corrected], DNA endoreduplication occurred in pRb-negative but not in pRb-positive cells, suggesting that functional pRb is necessary to prevent DNA replication in p21 G2-arrested cells. These results suggest that the primary target of the Cip/Kip family of inhibitors leading to efficient G1 arrest as well as to blockade of DNA replication from either G1 or G2 phase is the pRb regulatory system. Finally, the tendency of Rb-negative cells to undergo endoreduplication cycles when p21 is expressed may have negative implications in the therapy of Rb-negative cancers with genotoxic agents that activate the p53/p21 pathway.
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Affiliation(s)
- A B Niculescu
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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16
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Smeets M, Raymakers R, Vierwinden G, Pennings A, van de Locht L, Wessels H, Boezeman J, de Witte T. A low but functionally significant MDR1 expression protects primitive haemopoietic progenitor cells from anthracycline toxicity. Br J Haematol 1997; 96:346-55. [PMID: 9029024 DOI: 10.1046/j.1365-2141.1997.d01-2024.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Pgp is expressed on normal haemopoietic progenitor cells. The significance of the efflux pump in protecting normal progenitors for anthracycline toxicity is not defined and is the subject of this study. Pgp was measured in CD34+ progenitors with a rhodamine efflux assay. A high efflux, modulated by verapamil, was only found in a distinct subpopulation (20-30%). Pgp measured by the monoclonal antibody antibody (MoAb) MRK-16 was low in the rhodamine dull, but significantly (P < 0.04) higher than in the rhodamine bright cells. Reverse transcriptase polymerase chain reaction (RT-PCR) of MDR1 mRNA showed a very weak signal in both populations. In a single-cell clonogenic assay, rhodamine dull cells appeared less sensitive to anthracyclines (IC50 daunorubicin 0.005 microg/ml; adriamycin 0.03 microg/ml) compared to rhodamine bright cells (IC50 daunorubicin 0.0025 microg/ml; adriamycin 0.01 microg/ml). Furthermore, verapamil significantly (P < 0.05) potentiated anthracycline toxicity only in the rhodamine dull cells, proving its Pgp-specific modulating effect. Rhodamine dull cells gave larger and more mixed colonies compatible with a more primitive origin. Although detection with MoAbs and RT-PCR revealed a low Pgp level, functionally this Pgp appeared to be very important in protecting primitive progenitors against anthracycline toxicity. This protection can be jeopardized by administration of Pgp modulators.
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Affiliation(s)
- M Smeets
- Division of Haematology, University Hospital Nijmegen, The Netherlands
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17
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Abstract
We studied the appearance of retinoblastoma on unenhanced and gadolinium-enhanced images and the accuracy of tumour staging with MR imaging. The MR images were obtained in 18 children with retinoblastoma and compared with histopathological findings after enucleation. The MR imaging included T1-weighted and dual-echo T2-weighted images before, and T1-weighted images after, gadopentetate dimeglumine injection. The contrast between tumour and ipsilateral vitreous strongly increased (57 %) after gadolinium on T1-weighted images (p = 0.004). Tumour was strongly hypointense as compared with ipsilateral vitreous in all patients using heavily T2-weighted (TE = 120 ms) images (p = 0.001). The estimated T2 of tumour (mean 96 + 14 ms) did not correlate with histological grading or degree of calcification. Unenhanced T1-weighted MR images rightfully excluded extrascleral growth in 16 of 16 cases, but its presence was confirmed after enucleation in only one of 2 abnormal MR scans. Invasion of the optic nerve behind the cribriform plate was confirmed in 2 of 3 abnormal gadolinium-enhanced MR scans, but also in 1 of the 15 cases in which MR images were normal. The T2-weighted images were useful in assessing retinal detachment. We conclude that heavily T2-weighted images, unenhanced T1-weighted images and gadolinium-enhanced T1-weighted MR images are complementary in characterizing and staging retinoblastoma.
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Affiliation(s)
- F Barkhof
- Department of Diagnostic Radiology, Free University Hospital, P. O. Box 7057, NL-1007 MB Amsterdam, The Netherlands
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18
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Vreugdenhil G, Smeets M, Broekhuysen AM. Compliance with iron-chelation treatment after bone marrow transplantation. Lancet 1994; 343:604. [PMID: 7906360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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19
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Trimbos JB, Smeets M, Verdel M, Hermans J. Cosmetic result of lower midline laparotomy wounds: polybutester and nylon skin suture in a randomized clinical trial. Obstet Gynecol 1993; 82:390-3. [PMID: 8355939] [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: 01/30/2023]
Abstract
OBJECTIVE To compare the cosmetic outcome of lower midline laparotomy scars using either nylon or polybutester suture for skin closure. METHODS A randomized clinical trial compared polybutester skin suture with nylon for lower midline laparotomy wounds in 50 women undergoing gynecologic surgery. Scar hypertrophy, scar width, scar color, the presence of cross-hatching marks, and a total score were assessed in all patients at 18 months following surgery and compared by nonparametric statistical tests. RESULTS The wounds closed with polybutester suture were significantly less hypertrophic than those closed with nylon. Regardless of the suture material used, the lower part of the laparotomy scar showed an inferior cosmetic result compared with the upper part underneath the umbilicus for scar hypertrophy, scar width, and the total scar score. CONCLUSIONS Polybutester skin suture diminishes the risk of hypertrophic scarring because of its special properties allowing it to adapt to changing tensions in the wound. Increased closure tension of the skin in the midline region above the pubic bone may be caused by a relative immobility of the skin. Scar cosmetics in this area may be improved by extra subcuticular suture support.
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Affiliation(s)
- J B Trimbos
- Department of Gynecology, Leiden University Medical Center, The Netherlands
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20
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Vreugdenhil G, Smeets M, Feelders RA, van Eijk HG. Iron chelators may enhance erythropoiesis by increasing iron delivery to haematopoietic tissue and erythropoietin response in iron-loading anaemia. Acta Haematol 1993; 89:57-60. [PMID: 8503244 DOI: 10.1159/000204488] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [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: 01/31/2023]
Abstract
Based on the mode of action of iron chelators, one might expect a decrease in bone marrow iron availability, resulting in worsening of the anaemia in certain types of iron-loading anaemia. However, improvement of anaemia or reduction in transfusion requirements during chelation treatment has been reported in various types of iron-loading anaemia. It is suggested that iron chelators act as mediators facilitating iron release from storage sites and its delivery to haematopoietic tissues. In addition, a reduction of iron stores may upregulate erythropoietin response and bring about a decrease of disease activity in inflammatory disorders, resulting in a haemoglobin rise. Large trials with (oral) iron chelators are required to verify these possible effects.
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Affiliation(s)
- G Vreugdenhil
- Department of Internal Medicine, University Hospital, Nijmegen, The Netherlands
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21
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Vrensen G, Smeets M, Willekens B. The human eye lens is designed for longevity. Exp Eye Res 1992. [DOI: 10.1016/0014-4835(92)90859-q] [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: 11/26/2022]
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22
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Kateman E, Heederik D, Pal TM, Smeets M, Smid T, Spitteler M. Relationship of airborne microorganisms with the lung function and leucocyte levels of workers with a history of humidifier fever. Scand J Work Environ Health 1990; 16:428-33. [PMID: 2284591 DOI: 10.5271/sjweh.1764] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
An influenza-like illness appeared recently among workers in a plant processing synthetic yarn. A humidifier, a cold-water spraying system, was the suspected cause. Lung function changes over the day and week and changes in blood leucocytes were studied among the workers from the suspected department and two reference populations. Exposure to colony-forming units of bacteria and fungi and to endotoxins was also monitored. The workers from the suspected department had statistically significantly lower lung functions on the first workday of the week than the referents. Their blood leucocytes were also raised statistically significantly. The exposure to fungi, bacteria, and endotoxins differed significantly between the various departments, but the measured levels were low. It was concluded that the observed effects were suggestive of a "Monday morning fever" type of reaction and that adverse effects occurred at exposure levels lower than those found to date in the literature.
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Affiliation(s)
- E Kateman
- Department of Environmental and Tropical Health, University Wageningen, The Netherlands
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23
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Smeets M, Brunekreef B, Dijkstra L, Houthuijs D. Lung growth of pre-adolescent children. Eur Respir J 1990; 3:91-6. [PMID: 2311736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Lung growth was studied in 420 Dutch children aged 6-11 yrs. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) and maximal mid-expiratory flow (MMEF) were measured four times over a 2.5 yr period with a rolling-seal spirometer. In boys, pulmonary function increased with approximately the same velocity at all ages studied. In girls, however, the growth velocities of FVC and FEV1 increased markedly at age 10 yrs, and growth velocities of PEF and MMEF had increased already at age 9 yrs. The minimum pulmonary function growth velocity could not be determined from the available data in boys. In girls, the minimum pulmonary function growth velocities preceded the minimum height growth velocity at the onset of the pubertal growth spurt. All lung function growth rates were significantly associated with the growth rate of height. In girls, the growth rate of FVC was also associated with the weight growth rate. There was also some association between the growth rates of PEF and MMEF and age. In boys, there was a negative association between age and the growth rates of FVC and FEV1, after adjustment for the growth rate of height.
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Affiliation(s)
- M Smeets
- Dept of Environmental Health, University of Wageningen, The Netherlands
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24
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Smeets M, Brunekreef B, Dijkstra L, Houthuijs D. Lung growth of pre-adolescent children. Eur Respir J 1990. [DOI: 10.1183/09031936.93.03010091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Lung growth was studied in 420 Dutch children aged 6-11 yrs. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) and maximal mid-expiratory flow (MMEF) were measured four times over a 2.5 yr period with a rolling-seal spirometer. In boys, pulmonary function increased with approximately the same velocity at all ages studied. In girls, however, the growth velocities of FVC and FEV1 increased markedly at age 10 yrs, and growth velocities of PEF and MMEF had increased already at age 9 yrs. The minimum pulmonary function growth velocity could not be determined from the available data in boys. In girls, the minimum pulmonary function growth velocities preceded the minimum height growth velocity at the onset of the pubertal growth spurt. All lung function growth rates were significantly associated with the growth rate of height. In girls, the growth rate of FVC was also associated with the weight growth rate. There was also some association between the growth rates of PEF and MMEF and age. In boys, there was a negative association between age and the growth rates of FVC and FEV1, after adjustment for the growth rate of height.
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25
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