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Vlerick L, Devreese M, Peremans K, Dockx R, Croubels S, Duchateau L, Polis I. Pharmacokinetics, absolute bioavailability and tolerability of ketamine after intranasal administration to dexmedetomidine sedated dogs. PLoS One 2020; 15:e0227762. [PMID: 31929589 PMCID: PMC6957157 DOI: 10.1371/journal.pone.0227762] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 12/28/2019] [Indexed: 01/13/2023] Open
Abstract
Intranasal ketamine has recently gained interest in human medicine, not only for its sedative, anaesthetic or analgesic properties, but also in the management of treatment resistant depression, where it has been shown to be an effective, fast acting alternative treatment. Since several similarities are reported between human psychiatric disorders and canine anxiety disorders, intranasal ketamine could serve as an alternative treatment for anxiety disordered dogs. However, to the authors knowledge, intranasal administration of ketamine and its pharmacokinetics have never been described in dogs. Therefore, this study aimed to examine the pharmacokinetics, absolute bioavailability and tolerability of intranasal ketamine administration compared with intravenous administration. Seven healthy, adult laboratory Beagle dogs were included in this randomized crossover study. The dogs received 2 mg/kg body weight ketamine intravenously (IV) or intranasally (IN), with a two-week wash-out period. Prior to ketamine administration, dogs were sedated intramuscularly with dexmedetomidine. Venous blood samples were collected at fixed times until 480 min post-administration and ketamine plasma concentrations were determined by liquid chromatography-tandem mass spectrometry. Cardiovascular parameters and sedation scores were recorded at the same time points. Non-compartmental pharmacokinetic analysis revealed a rapid (Tmax = 0.25 ± 0.14 h) and complete IN bioavailability (F = 147.65 ± 49.97%). Elimination half-life was similar between both administration routes (T1/2el IV = 1.47 ± 0.24 h, T1/2el IN = 1.50 ± 0.97 h). Heart rate and sedation scores were significantly higher at 5 and 10 min following IV administration compared to IN administration, but not at the later time-points.
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Affiliation(s)
- Lise Vlerick
- Small Animal Department, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
- * E-mail:
| | - Mathias Devreese
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Kathelijne Peremans
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Robrecht Dockx
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
- Department of Psychiatry and Medical Psychology, Ghent Experimental Psychiatry (GHEP) lab, Ghent University, Ghent, Belgium
| | - Siska Croubels
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Luc Duchateau
- Biometrics Research Centre, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Ingeborgh Polis
- Small Animal Department, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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Asadian M, Chan KV, Norouzi M, Grande S, Cools P, Morent R, De Geyter N. Fabrication and Plasma Modification of Nanofibrous Tissue Engineering Scaffolds. Nanomaterials (Basel) 2020; 10:E119. [PMID: 31936372 PMCID: PMC7023287 DOI: 10.3390/nano10010119] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/13/2019] [Accepted: 12/21/2019] [Indexed: 12/15/2022]
Abstract
This paper provides a comprehensive overview of nanofibrous structures for tissue engineering purposes and the role of non-thermal plasma technology (NTP) within this field. Special attention is first given to nanofiber fabrication strategies, including thermally-induced phase separation, molecular self-assembly, and electrospinning, highlighting their strengths, weaknesses, and potentials. The review then continues to discuss the biodegradable polyesters typically employed for nanofiber fabrication, while the primary focus lies on their applicability and limitations. From thereon, the reader is introduced to the concept of NTP and its application in plasma-assisted surface modification of nanofibrous scaffolds. The final part of the review discusses the available literature on NTP-modified nanofibers looking at the impact of plasma activation and polymerization treatments on nanofiber wettability, surface chemistry, cell adhesion/proliferation and protein grafting. As such, this review provides a complete introduction into NTP-modified nanofibers, while aiming to address the current unexplored potentials left within the field.
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Affiliation(s)
- Mahtab Asadian
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
| | - Ke Vin Chan
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
| | - Mohammad Norouzi
- Department of Biomedical Engineering, University of Manitoba, Winnipeg, MB R3E 0Z3, Canada;
| | - Silvia Grande
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
| | - Pieter Cools
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
| | - Rino Morent
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
| | - Nathalie De Geyter
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41, B4, B-9000 Ghent, Belgium; (K.V.C.); (S.G.); (P.C.); (R.M.); (N.D.G.)
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De Kesel J, Gómez-Rodríguez R, Bonneure E, Mangelinckx S, Kyndt T. The Use of PTI-Marker Genes to Identify Novel Compounds that Establish Induced Resistance in Rice. Int J Mol Sci 2020; 21:E317. [PMID: 31906566 PMCID: PMC6981679 DOI: 10.3390/ijms21010317] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/20/2019] [Accepted: 12/23/2019] [Indexed: 01/04/2023] Open
Abstract
Compounds that establish induced resistance (IR) in plants are promising alternatives for the pesticides that are progressively being banned worldwide. Screening platforms to identify IR-establishing compounds have been developed, but none were specifically designed for monocot plants. Here, we propose the use of an RT-qPCR screening platform, based on conserved immunity marker genes of rice as proxy for IR induction. Central regulators of biotic stress responses of rice were identified with a weighted gene co-expression network analysis (WGCNA), using more than 350 microarray datasets of rice under various sorts of biotic stress. Candidate genes were narrowed down to six immunity marker genes, based on consistent association with pattern-triggered immunity (PTI), both in rice plants as in rice cell suspension cultures (RCSCs). By monitoring the expression of these genes in RCSCs upon treatment with candidate IR-inducing compounds, we showed that our marker genes can predict IR induction in rice. Diproline, a novel IR-establishing compound for monocots that was detected with these marker genes, was shown to induce rice resistance against root-knot nematodes, without fitness costs. Gene expression profiling of the here-described PTI-marker genes can be executed on fully-grown plants or in RCSCs, providing a novel and versatile tool to predict IR induction.
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Affiliation(s)
- Jonas De Kesel
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.D.K.); (R.G.-R.)
| | - Ramsés Gómez-Rodríguez
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.D.K.); (R.G.-R.)
| | - Eli Bonneure
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (E.B.); (S.M.)
| | - Sven Mangelinckx
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (E.B.); (S.M.)
| | - Tina Kyndt
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; (J.D.K.); (R.G.-R.)
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Coenen A, Verhaeghe PP, Van de Putte B. Ethnic Residential Segregation: A Family Matter? An Integration of Household Composition Characteristics into the Residential Segregation Literature. Eur J Popul 2019; 35:1023-1052. [PMID: 31832034 PMCID: PMC6882974 DOI: 10.1007/s10680-018-09514-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 12/18/2018] [Indexed: 10/27/2022]
Abstract
The ethnic residential segregation literature seldom considers household characteristics, despite their importance for residential mobility. This study offers a first step to amend this lacuna by focussing on the relationship between marital status and the presence of children on the one hand and the extent to which ethnic majority households live segregated on the other. We investigated this association with data from the 2011 Belgian Census. We performed a conditional logit model on a sample of households formed by young adults of Belgian origin living in the metropolitan areas of Antwerp (N = 11,241), Brussels (N = 6690), Charleroi (N = 3483), Ghent (N = 7825) and Liège (N = 5873). It appeared that households with children are less likely than childless households to live in diverse neighbourhoods. Considering partnership status, we find that singles are the most likely to live in diverse neighbourhoods. Amongst the couples without children, those couples in legal cohabitation are less likely to live in diverse neighbourhoods than married or other unmarried couples, while married couples with children are less likely to do so when comparing to unmarried couples with children, both legally cohabiting and others. We, therefore, conclude that it is important to consider (the interaction between) partnership status and the presence of children when studying ethnic residential segregation.
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Affiliation(s)
- Ad Coenen
- Department of Sociology, Ghent University, Korte Meer 5, 9000 Ghent, Belgium
| | - Pieter-Paul Verhaeghe
- Department of Sociology, Ghent University, Korte Meer 5, 9000 Ghent, Belgium
- Department of Sociology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Bart Van de Putte
- Department of Sociology, Ghent University, Korte Meer 5, 9000 Ghent, Belgium
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Wood J, Neels K. Local Childcare Availability and Dual-Earner Fertility: Variation in Childcare Coverage and Birth Hazards Over Place and Time. Eur J Popul 2019; 35:913-937. [PMID: 31832030 PMCID: PMC6883015 DOI: 10.1007/s10680-018-9510-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 12/02/2018] [Indexed: 06/10/2023]
Abstract
The theoretically well-grounded hypothesis that the availability of formal childcare has a positive impact on childbearing in the developed world has been part of the population literature for a long time. Whereas the participation of women in the labour force created a tension between work and family life, the increasing availability of formal childcare in many developed countries is assumed to reconcile these two life domains due to lower opportunity costs and compatible mother and worker roles. However, previous empirical studies on the association between childcare availability and fertility exhibit ambiguous results and considerable variation in the methods applied. This study assesses the childcare-fertility hypothesis for Belgium, a consistently top-ranked country concerning formal childcare coverage that also exhibits considerable variation within the country. Using detailed longitudinal census and register data for the 2000s combined with childcare coverage rates for 588 municipalities and allowing for the endogenous nature of formal childcare and selective migration, our findings indicate clear and substantial positive effects of local formal childcare provision on birth hazards, especially when considering the transition to parenthood. In addition, this article quantifies the impact of local formal childcare availability on fertility at the aggregate level and shows that in the context of low and lowest-low fertility levels in the developed world, the continued extension of formal childcare services can be a fruitful tool to stimulate childbearing among dual-earner couples.
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Affiliation(s)
- Jonas Wood
- Centre for Longitudinal and Life-Course Studies, University of Antwerp, Antwerp, Belgium
| | - Karel Neels
- Centre for Longitudinal and Life-Course Studies, University of Antwerp, Antwerp, Belgium
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Verbrugghe E, Van Rooij P, Favoreel H, Martel A, Pasmans F. In vitro modeling of Batrachochytrium dendrobatidis infection of the amphibian skin. PLoS One 2019; 14:e0225224. [PMID: 31725762 PMCID: PMC6855447 DOI: 10.1371/journal.pone.0225224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/30/2019] [Indexed: 11/19/2022] Open
Abstract
The largest current disease-induced loss of vertebrate biodiversity is due to chytridiomycosis and despite the increasing understanding of the pathogenesis, knowledge unravelling the early host-pathogen interactions remains limited. Batrachochytrium dendrobatidis (Bd) zoospores attach to and invade the amphibian epidermis, with subsequent invasive growth in the host skin. Availability of an in vitro assay would facilitate in depth study of this interaction while reducing the number of experimental animals needed. We describe a fluorescent cell-based in vitro infection model that reproduces host-Bd interactions. Using primary keratinocytes from Litoria caerulea and the epithelial cell line A6 from Xenopus laevis, we reproduced different stages of host cell infection and intracellular growth of Bd, resulting in host cell death, a key event in chytridiomycosis. The presented in vitro models may facilitate future mechanistic studies of host susceptibility and pathogen virulence.
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Affiliation(s)
- Elin Verbrugghe
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
- * E-mail:
| | - Pascale Van Rooij
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Herman Favoreel
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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De Roeck A, De Coster W, Bossaerts L, Cacace R, De Pooter T, Van Dongen J, D’Hert S, De Rijk P, Strazisar M, Van Broeckhoven C, Sleegers K. NanoSatellite: accurate characterization of expanded tandem repeat length and sequence through whole genome long-read sequencing on PromethION. Genome Biol 2019; 20:239. [PMID: 31727106 PMCID: PMC6857246 DOI: 10.1186/s13059-019-1856-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 10/10/2019] [Indexed: 12/13/2022] Open
Abstract
Technological limitations have hindered the large-scale genetic investigation of tandem repeats in disease. We show that long-read sequencing with a single Oxford Nanopore Technologies PromethION flow cell per individual achieves 30× human genome coverage and enables accurate assessment of tandem repeats including the 10,000-bp Alzheimer's disease-associated ABCA7 VNTR. The Guppy "flip-flop" base caller and tandem-genotypes tandem repeat caller are efficient for large-scale tandem repeat assessment, but base calling and alignment challenges persist. We present NanoSatellite, which analyzes tandem repeats directly on electric current data and improves calling of GC-rich tandem repeats, expanded alleles, and motif interruptions.
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Affiliation(s)
- Arne De Roeck
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Wouter De Coster
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Liene Bossaerts
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Rita Cacace
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Tim De Pooter
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Jasper Van Dongen
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Svenn D’Hert
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Peter De Rijk
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Mojca Strazisar
- Neuromics Support Facility, Center for Molecular Neurology, VIB - University of Antwerp, Antwerp, Belgium
| | - Christine Van Broeckhoven
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Kristel Sleegers
- Neurodegenerative Brain Diseases Group, VIB Center for Molecular Neurology, University of Antwerp-CDE, Universiteitsplein 1, B-2610 Antwerp, Belgium
- Biomedical Sciences, University of Antwerp, Antwerp, Belgium
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Vera L, Campos Arias D, Muylle S, Stergiopulos N, Segers P, van Loon G. A 1D computer model of the arterial circulation in horses: An important resource for studying global interactions between heart and vessels under normal and pathological conditions. PLoS One 2019; 14:e0221425. [PMID: 31433827 PMCID: PMC6703698 DOI: 10.1371/journal.pone.0221425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/06/2019] [Indexed: 11/18/2022] Open
Abstract
Arterial rupture in horses has been observed during exercise, after phenylephrine administration or during parturition (uterine artery). In human pathophysiological research, the use of computer models for studying arterial hemodynamics and understanding normal and abnormal characteristics of arterial pressure and flow waveforms is very common. The objective of this research was to develop a computer model of the equine arterial circulation, in order to study local intra-arterial pressures and flow dynamics in horses. Morphologically, large differences exist between human and equine aortic arch and arterial branching patterns. Development of the present model was based on post-mortem obtained anatomical data of the arterial tree (arterial lengths, diameters and branching angles); in vivo collected ultrasonographic flow profiles from the common carotid artery, external iliac artery, median artery and aorta; and invasively collected pressure curves from carotid artery and aorta. These data were used as input for a previously validated (in humans) 1D arterial network model. Data on terminal resistance and arterial compliance parameters were tuned to equine physiology. Given the large arterial diameters, Womersley theory was used to compute friction coefficients, and the input into the arterial system was provided via a scaled time-varying elastance model of the left heart. Outcomes showed plausible predictions of pressure and flow waveforms throughout the considered arterial tree. Simulated flow waveform morphology was in line with measured flow profiles. Consideration of gravity further improved model based predicted waveforms. Derived flow waveform patterns could be explained using wave power analysis. The model offers possibilities as a research tool to predict changes in flow profiles and local pressures as a result of strenuous exercise or altered arterial wall properties related to age, breed or gender.
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Affiliation(s)
- Lisse Vera
- Equine Cardioteam Ghent University, Dept. of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
- * E-mail:
| | - Daimé Campos Arias
- IBiTech-bioMMeda, Ghent University, Ghent, Belgium
- Biomechanics and Biomaterials Research Group, CUJAE, Havana, Cuba
| | - Sofie Muylle
- Dept. of Morphology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Nikos Stergiopulos
- Laboratory of Hemodynamics and Cardiovascular Technology, EPFL, Lausanne, Switzerland
| | | | - Gunther van Loon
- Equine Cardioteam Ghent University, Dept. of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
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Ostyn NR, Steele JA, De Prins M, Sree SP, Chandran CV, Wangermez W, Vanbutsele G, Seo JW, Roeffaers MBJ, Breynaert E, Martens JA. Low-temperature activation of carbon black by selective photocatalytic oxidation. Nanoscale Adv 2019; 1:2873-2880. [PMID: 36133590 PMCID: PMC9416906 DOI: 10.1039/c9na00188c] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 05/21/2019] [Indexed: 06/15/2023]
Abstract
Carbon black is chemically modified by selective photocatalytic oxidation, removing amorphous carbon and functionalizing the graphitic fraction to produce porous, graphitized carbon black, commonly used as an adsorbent in chromatography. In contrast to pyrolytic treatments, this photocatalytic modification proceeds under mild reaction conditions using oxygen, nitric oxide, water vapor and a titanium dioxide photocatalyst at 150 °C. The photo-oxidation can be performed both with the photocatalyst in close proximity (contact mode) or physically separated from the carbon. Structural analysis of remotely photo-oxidized carbon black reveals increased hydrophilic properties as compared to pyrolysis at 700 °C in a N2 atmosphere. Carbon black photo-oxidation selectively mineralizes sp3-hybridized carbon, leading to enhanced graphitization. This results in an overall improved structural ordering by enriching carbon black with sp2-hybridized graphitic carbon showing decreased interplanar distance, accompanied by a twofold increase in the specific surface area. In addition, the photo-oxidized material is activated by the presence of oxygen functionalities on the graphitic carbon fraction, further enhancing the adsorptive properties.
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Affiliation(s)
- Niels R Ostyn
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Julian A Steele
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Michiel De Prins
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | | | - C Vinod Chandran
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Wauter Wangermez
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Gina Vanbutsele
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Jin Won Seo
- Department of Materials Engineering, KU Leuven Kasteelpark Arenberg 44 3001 Heverlee Belgium
| | - Maarten B J Roeffaers
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Eric Breynaert
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
| | - Johan A Martens
- Centre for Surface Chemistry and Catalysis, KU Leuven Celestijnenlaan 200F, box 2461 3001 Heverlee Belgium +32 16 32 16 37
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Schroé H, Van der Mispel C, De Bourdeaudhuij I, Verloigne M, Poppe L, Crombez G. A factorial randomised controlled trial to identify efficacious self-regulation techniques in an e- and m-health intervention to target an active lifestyle: study protocol. Trials 2019; 20:340. [PMID: 31182147 PMCID: PMC6558816 DOI: 10.1186/s13063-019-3456-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 05/20/2019] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Sufficient physical activity and a limited amount of sedentary behaviour can prevent a range of chronic diseases. However, most adults do not meet the recommendations for physical activity and sedentary behaviour. Effective and engaging interventions are needed to change people's behaviour. E- and m-health interventions are promising, but unfortunately they result in small effects and suffer from high attrition rates. Improvements to intervention content and design are required. Qualitative research has revealed the need for clear and concise interventions. Furthermore, many interventions use a range of behaviour-change techniques, and it is yet unknown whether these techniques are equally important to obtain behaviour change. It may well be that a limited set of these techniques is sufficient. In this study, the aim is to experimentally investigate the efficacy of three behaviour-change techniques (i.e. action planning, coping planning and self-monitoring) on physical activity, sedentary behaviour and related determinants among adults. METHODS In a 2 x 2 x 2 factorial trial participants will be randomly allocated to eight groups (including one control group). Each group will receive a different version of the self-regulation-based e- and m-health intervention 'MyPlan 2.0', in which three behaviour-change techniques (i.e. action planning, coping planning, self-monitoring) will be combined in order to achieve self-formulated goals about physical activity or sedentary behaviour. Goal attainment, and levels of physical activity and sedentary behaviour will be measured via self-report questionnaires. DISCUSSION This study should provide insight into the role of various behaviour-change techniques in changing health behaviour and its determinants. Its experimental and longitudinal design, with repeated measures of several determinants of behaviour change, allows an in-depth analysis of the processes underlying behaviour change, enabling the authors to provide guidance for the development of future e- and m-health interventions. TRIAL REGISTRATION This study is registered as MyPlan 2.0 as a clinical trial (ID number: NCT03274271 ). Release date: 20 October 2017.
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Affiliation(s)
- Helene Schroé
- Ghent Health Psychology Lab, Department of Experimental-Clinical and Health Psychology, Faculty of Psychology and Educational Sciences, Ghent University, Henri Dunantlaan 2, Ghent, 9000 Belgium
- Research Group Physical Activity and Health, Department of Movement and Sports Sciences, Faculty of Medicine and Health, Ghent University, Watersportlaan 2, Ghent, 9000 Belgium
| | - Celien Van der Mispel
- Ghent Health Psychology Lab, Department of Experimental-Clinical and Health Psychology, Faculty of Psychology and Educational Sciences, Ghent University, Henri Dunantlaan 2, Ghent, 9000 Belgium
- Research Group Physical Activity and Health, Department of Movement and Sports Sciences, Faculty of Medicine and Health, Ghent University, Watersportlaan 2, Ghent, 9000 Belgium
| | - Ilse De Bourdeaudhuij
- Research Group Physical Activity and Health, Department of Movement and Sports Sciences, Faculty of Medicine and Health, Ghent University, Watersportlaan 2, Ghent, 9000 Belgium
| | - Maïté Verloigne
- Research Group Physical Activity and Health, Department of Movement and Sports Sciences, Faculty of Medicine and Health, Ghent University, Watersportlaan 2, Ghent, 9000 Belgium
| | - Louise Poppe
- Ghent Health Psychology Lab, Department of Experimental-Clinical and Health Psychology, Faculty of Psychology and Educational Sciences, Ghent University, Henri Dunantlaan 2, Ghent, 9000 Belgium
- Research Group Physical Activity and Health, Department of Movement and Sports Sciences, Faculty of Medicine and Health, Ghent University, Watersportlaan 2, Ghent, 9000 Belgium
| | - Geert Crombez
- Ghent Health Psychology Lab, Department of Experimental-Clinical and Health Psychology, Faculty of Psychology and Educational Sciences, Ghent University, Henri Dunantlaan 2, Ghent, 9000 Belgium
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Vlerick L, Peremans K, Dockx R, Audenaert K, Baeken C, De Spiegeleer B, Saunders J, Polis I. The influence of subanaesthetic ketamine on regional cerebral blood flow in healthy dogs measured with 99mTc-HMPAO SPECT. PLoS One 2018; 13:e0209316. [PMID: 30562399 PMCID: PMC6298672 DOI: 10.1371/journal.pone.0209316] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 12/04/2018] [Indexed: 02/06/2023] Open
Abstract
Subanaesthetic ketamine has recently been proven to be a highly effective and fast acting alternative treatment for several psychiatric disorders. The mechanisms responsible for ketamine's antidepressant effects remain unclear, but a possible explanation could be that ketamine interacts with regional cerebral blood flow (rCBF). Therefore, the effects of two subanaesthetic ketamine doses on rCBF were evaluated. Twelve dogs were randomly assigned to one of the three treatment conditions (condition saline, condition 0.5 mg/kg ketamine or condition 2 mg/kg ketamine) and received in total five saline or ketamine infusions, with one week interval. Single Photon Emission Computed Tomography (SPECT) scans with the radiotracer 99mTc-hexamethylpropylene amine oxime were performed before the start of the infusions (baseline) and 24 hours after the first (single) and last (multiple) infusion. After a wash out period of 3 months, the animals were again assigned to one of the three treatment conditions described above and the infusion/scan protocol was repeated. During the infusions, cardiovascular parameters were evaluated every ten minutes. A one-way repeated measure ANOVA was set up to assess perfusion index for each ketamine dose for the left frontal cortex (alpha = 0.05). The remaining 11 brain regions were post hoc assessed. Perfusion index was significantly increased in the left frontal cortex and in the thalamus 24 hours after single and multiple ketamine infusions compared to baseline in the 2 mg/kg condition. No clinically relevant cardiovascular effects were observed during the ketamine infusions. This study shows that subanaesthetic ketamine can increase neuronal perfusion and therefore alter neuronal function in brain regions involved in depression and anxiety disorders. These perfusion increases may possibly contribute to ketamine's beneficial effects in these psychiatric disorders.
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Affiliation(s)
- Lise Vlerick
- Department of Small Animal, Faculty of Veterinary Medicine, Ghent University, Merelbeke, East Flanders, Belgium
| | - Kathelijne Peremans
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, East Flanders, Belgium
| | - Robrecht Dockx
- Ghent Experimental Psychiatry (GHEP) lab, Department of Psychiatry and Medical Psychology, Ghent University, Ghent, East Flanders, Belgium
| | - Kurt Audenaert
- Ghent Experimental Psychiatry (GHEP) lab, Department of Psychiatry and Medical Psychology, Ghent University, Ghent, East Flanders, Belgium
| | - Chris Baeken
- Ghent Experimental Psychiatry (GHEP) lab, Department of Psychiatry and Medical Psychology, Ghent University, Ghent, East Flanders, Belgium
| | - Bart De Spiegeleer
- Drug Quality and Registration (DruQuaR) group, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, East Flanders, Belgium
| | - Jimmy Saunders
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, East Flanders, Belgium
| | - Ingeborgh Polis
- Department of Small Animal, Faculty of Veterinary Medicine, Ghent University, Merelbeke, East Flanders, Belgium
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Vandewiele G, De Backere F, Lannoye K, Vanden Berghe M, Janssens O, Van Hoecke S, Keereman V, Paemeleire K, Ongenae F, De Turck F. A decision support system to follow up and diagnose primary headache patients using semantically enriched data. BMC Med Inform Decis Mak 2018; 18:98. [PMID: 30424769 PMCID: PMC6234630 DOI: 10.1186/s12911-018-0679-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 10/18/2018] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Headache disorders are an important health burden, having a large health-economic impact worldwide. Current treatment & follow-up processes are often archaic, creating opportunities for computer-aided and decision support systems to increase their efficiency. Existing systems are mostly completely data-driven, and the underlying models are a black-box, deteriorating interpretability and transparency, which are key factors in order to be deployed in a clinical setting. METHODS In this paper, a decision support system is proposed, composed of three components: (i) a cross-platform mobile application to capture the required data from patients to formulate a diagnosis, (ii) an automated diagnosis support module that generates an interpretable decision tree, based on data semantically annotated with expert knowledge, in order to support physicians in formulating the correct diagnosis and (iii) a web application such that the physician can efficiently interpret captured data and learned insights by means of visualizations. RESULTS We show that decision tree induction techniques achieve competitive accuracy rates, compared to other black- and white-box techniques, on a publicly available dataset, referred to as migbase. Migbase contains aggregated information of headache attacks from 849 patients. Each sample is labeled with one of three possible primary headache disorders. We demonstrate that we are able to reduce the classification error, statistically significant (ρ≤0.05), with more than 10% by balancing the dataset using prior expert knowledge. Furthermore, we achieve high accuracy rates by using features extracted using the Weisfeiler-Lehman kernel, which is completely unsupervised. This makes it an ideal approach to solve a potential cold start problem. CONCLUSION Decision trees are the perfect candidate for the automated diagnosis support module. They achieve predictive performances competitive to other techniques on the migbase dataset and are, foremost, completely interpretable. Moreover, the incorporation of prior knowledge increases both predictive performance as well as transparency of the resulting predictive model on the studied dataset.
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Affiliation(s)
- Gilles Vandewiele
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | - Femke De Backere
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | - Kiani Lannoye
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | | | - Olivier Janssens
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | - Sofie Van Hoecke
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | - Vincent Keereman
- Department of Neurology, Ghent University Hospital, Corneel Heymanslaan 10, Ghent, 9000 Belgium
| | - Koen Paemeleire
- Department of Neurology, Ghent University Hospital, Corneel Heymanslaan 10, Ghent, 9000 Belgium
| | - Femke Ongenae
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
| | - Filip De Turck
- IDLab, Ghent University - imec, Technologiepark 15, Ghent, 9052 Belgium
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Abstract
ADHD is considered a disorder of self-regulation. Recent research has shown that awareness of bodily states, referred to as interoceptive awareness, crucially contributes to self-regulatory processes. Impaired self-regulation in ADHD has been explained in terms of arousal regulation deficits in ADHD (the state regulation deficit (SRD) account). There is now ample support for the SRD account, however the exact reason for arousal regulation difficulties is not yet known. The SRD account explicitly refers to the ability to monitor one's momentary bodily state as a prerequisite for effective state regulation. However, surprisingly, no study to date has tested the ability to become aware of bodily signals, i.e. interoceptive awareness, in ADHD. In the current study, we therefore compared interoceptive awareness between 24 adults with ADHD and 23 controls by means of both an objective (heartbeat perception task) and subjective measure (questionnaire) of interoceptive awareness. Results revealed a strikingly similar performance for both groups on both measures, suggesting preserved interoceptive awareness in adult ADHD.
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Affiliation(s)
- Jan R. Wiersema
- Department of Experimental Clinical and Health psychology, Faculty of Psychology and educational sciences, Ghent University, Ghent, Belgium
- * E-mail:
| | - Elke Godefroid
- Department of Experimental Clinical and Health psychology, Faculty of Psychology and educational sciences, Ghent University, Ghent, Belgium
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Peters G, Maertens J, Lammertyn J, De Mey M. Exploring of the feature space of de novo developed post-transcriptional riboregulators. PLoS Comput Biol 2018; 14:e1006170. [PMID: 30118473 PMCID: PMC6114898 DOI: 10.1371/journal.pcbi.1006170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 08/29/2018] [Accepted: 04/30/2018] [Indexed: 11/23/2022] Open
Abstract
Metabolic engineering increasingly depends upon RNA technology to customly rewire the metabolism to maximize production. To this end, pure riboregulators allow dynamic gene repression without the need of a potentially burdensome coexpressed protein like typical Hfq binding small RNAs and clustered regularly interspaced short palindromic repeats technology. Despite this clear advantage, no clear general design principles are available to de novo develop repressing riboregulators, limiting the availability and the reliable development of these type of riboregulators. Here, to overcome this lack of knowledge on the functionality of repressing riboregulators, translation inhibiting RNAs are developed from scratch. These de novo developed riboregulators explore features related to thermodynamical and structural factors previously attributed to translation initiation modulation. In total, 12 structural and thermodynamic features were defined of which six features were retained after removing correlations from an in silico generated riboregulator library. From this translation inhibiting RNA library, 18 riboregulators were selected using a experimental design and subsequently constructed and co-expressed with two target untranslated regions to link the translation inhibiting RNA features to functionality. The pure riboregulators in the design of experiments showed repression down to 6% of the original protein expression levels, which could only be partially explained by a ordinary least squares regression model. To allow reliable forward engineering, a partial least squares regression model was constructed and validated to link the properties of translation inhibiting RNA riboregulators to gene repression. In this model both structural and thermodynamic features were important for efficient gene repression by pure riboregulators. This approach enables a more reliable de novo forward engineering of effective pure riboregulators, which further expands the RNA toolbox for gene expression modulation. To allow reliable forward engineering of microbial cell factories, various metabolic engineering efforts rely on RNA-based technology. As such, programmable riboregulators allow dynamic control over gene expression. However, no clear design principles exist for de novo developed repressing riboregulators, which limits their applicability. Here, various engineering principles are identified and computationally explored. Subsequently, various design criteria are used in an experimental design, which were explored in an in vivo study. This resulted in a regression model that enables a more reliable computational design of repression small RNAs.
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Affiliation(s)
- Gert Peters
- Centre for Synthetic Biology, Ghent University, Ghent, Belgium
| | - Jo Maertens
- Centre for Synthetic Biology, Ghent University, Ghent, Belgium
| | | | - Marjan De Mey
- Centre for Synthetic Biology, Ghent University, Ghent, Belgium
- * E-mail:
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Van Roten A, Barakat AZAZ, Wouters A, Tran TA, Mouton S, Noben JP, Gentile L, Smeets K. A carcinogenic trigger to study the function of tumor suppressor genes in Schmidtea mediterranea. Dis Model Mech 2018; 11:dmm032573. [PMID: 29967069 PMCID: PMC6176991 DOI: 10.1242/dmm.032573] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 06/25/2018] [Indexed: 12/30/2022] Open
Abstract
Planarians have been long known for their regenerative ability, which hinges on pluripotency. Recently, however, the planarian model has been successfully established for routine toxicological screens aimed to assess overproliferation, mutagenicity and tumorigenesis. In this study, we focused on planarian tumor suppressor genes (TSGs) and their role during chemically induced carcinogenic stress in Schmidtea mediterranea Combining in silico and proteomic screens with exposure to human carcinogen type 1A agent cadmium (Cd), we showed that many TSGs have a function in stem cells and that, in general, exposure to Cd accelerated the onset and increased the severity of the observed phenotype. This suggested that the interaction between environmental and genetic factors plays an important role in tumor development in S. mediterranea Therefore, we further focused on the synergistic effects of Cd exposure and p53 knockdown (KD) at the cellular and molecular levels. Cd also produced a specific proteomic landscape in homeostatic animals, with 172 proteins differentially expressed, 43 of which were downregulated. Several of these proteins have tumor suppressor function in human and other animals, namely Wilms Tumor 1 Associated Protein (WT1), Heat Shock Protein 90 (HSP90), Glioma Pathogenesis-Related Protein 1 (GLIPR1) and Matrix Metalloproteinase B (Smed-MMPB). Both Glipr1 and MmpB KD produced large outgrowths, epidermal lesions and epidermal blisters. The epidermal blisters that formed as a consequence of Smed-MmpB KD were populated by smedwi1+ cells, many of which were actively proliferating, while large outgrowths contained ectopically differentiated structures, such as photoreceptors, nervous tissue and a small pharynx. In conclusion, Smed-MmpB is a planarian TSG that prevents stem cell proliferation and differentiation outside the proper milieu.
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Affiliation(s)
- Andromeda Van Roten
- Zoology: Biodiversity and Toxicology, Hasselt University-Campus Diepenbeek, Agoralaan 1, Gebouw D, 3590, Diepenbeek, Belgium
| | - Amal Zohir Abo-Zeid Barakat
- Planarian Stem Cell Laboratory, Max Planck Institute for Molecular Biomedicine, von Esmarch-str. 54, 48149, Münster, Germany
| | - Annelies Wouters
- Zoology: Biodiversity and Toxicology, Hasselt University-Campus Diepenbeek, Agoralaan 1, Gebouw D, 3590 Diepenbeek, Belgium
| | - Thao Anh Tran
- Pluripotency and Regeneration Group, Fraunhofer Institute for Biomedical Engineering, Joseph-von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Stijn Mouton
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, 9713, Groningen, The Netherlands
| | - Jean-Paul Noben
- Biomedical Research Institute, Hasselt University and Transnationale Universiteit Limburg, School of Life Sciences, 3590, Diepenbeek, Belgium
| | - Luca Gentile
- Planarian Stem Cell Laboratory, Max Planck Institute for Molecular Biomedicine, von Esmarch-str. 54, 48149, Münster, Germany
| | - Karen Smeets
- Zoology: Biodiversity and Toxicology, Hasselt University-Campus Diepenbeek, Agoralaan 1, Gebouw D, 3590, Diepenbeek, Belgium
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Malcolm P, Galle S, Van den Berghe P, De Clercq D. Exoskeleton assistance symmetry matters: unilateral assistance reduces metabolic cost, but relatively less than bilateral assistance. J Neuroeng Rehabil 2018; 15:74. [PMID: 30092800 PMCID: PMC6085709 DOI: 10.1186/s12984-018-0381-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 05/03/2018] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Many gait impairments are characterized by asymmetry and result in reduced mobility. Exoskeletons could be useful for restoring gait symmetry by assisting only one leg. However, we still have limited understanding of the effects of unilateral exoskeleton assistance. Our aim was to compare the effects of unilateral and bilateral assistance using a within-subject study design. METHODS Eleven participants walked in different exoskeleton conditions. In the Unilateral conditions, only one leg was assisted. In Bilateral Matched Total Work, half of the assistance from the Unilateral conditions was applied to both legs such that the bilateral sum was equal to that of the Unilateral conditions. In Bilateral Matched Work Per Leg, the same assistance as in the Unilateral conditions was provided to both legs such that the bilateral sum was the double of that of the Unilateral conditions. In the Powered-Off condition, no assistance was provided. We measured metabolic energy consumption, exoskeleton mechanics and kinematics. RESULTS On average, the Unilateral, Bilateral Matched Total Work and Bilateral Matched Work Per Leg conditions reduced the metabolic rate by 7, 11 and 15%, respectively, compared with the Powered-Off condition. A possible explanation for why the Unilateral conditions effectively reduced the metabolic rate could be that they caused only very little asymmetry in gait biomechanics, except at the ankle and in the horizontal center-of-mass velocity. We found the highest ratio of metabolic rate reduction versus positive work assistance with bilateral assistance and low work per leg (Bilateral Matched Total Work). Statistical analysis indicated that assistance symmetry and assistance per leg are more important than the bilateral summed assistance for reducing the metabolic rate of walking. CONCLUSIONS These data bridge the gap between conclusions from studies with unilateral and bilateral exoskeletons and inform how unilateral assistance can be used to influence gait parameters, such as center-of-mass velocity.
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Affiliation(s)
- Philippe Malcolm
- Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska Omaha, Omaha, NE 68182 USA
- Department of Movement and Sports Sciences, Ghent University, B-9000 Ghent, Belgium
| | - Samuel Galle
- Department of Movement and Sports Sciences, Ghent University, B-9000 Ghent, Belgium
| | | | - Dirk De Clercq
- Department of Movement and Sports Sciences, Ghent University, B-9000 Ghent, Belgium
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Van Ryckeghem DML, Van Damme S, Vervoort T. Does attention bias modification training impact on task performance in the context of pain: An experimental study in healthy participants. PLoS One 2018; 13:e0200629. [PMID: 30020983 PMCID: PMC6051628 DOI: 10.1371/journal.pone.0200629] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/29/2018] [Indexed: 11/18/2022] Open
Abstract
Attention has been theorized to play a key role in the experience of pain and associated task interference. Training attention away from pain via attention bias modification (ABM) training techniques has been proposed to improve pain-related outcomes, but evidence is inconsistent. In an experimental study, we investigated the impact of a single session ABM training -using a visual probe paradigm with idiosyncratic pain words- on cold pressor test (CPT) pain experience and task interference by pain. Fifty-eight healthy volunteers were randomly assigned to an ABM training group (N = 28; attending away from pain) and a sham training group (N = 30; no training direction). At pre-training, participants performed a baseline Random-Interval-Repetition (RIR) task and the CPT. Participants reported on sensations they experienced during the baseline CPT. Relevant descriptors were integrated in the visual probe paradigm during the training phase. At post-training, participants completed the RIR task again while experiencing CPT pain. Participants also reported on the extent they attended to the pain and the intensity/unpleasantness of the pain. Results indicated that, in contrast with our hypotheses, ABM training did also not reduce task interference due to CPT pain. Furthermore, ABM training did not change self-reported attending to CPT pain. Finally, ABM training did not reduce CPT pain intensity or pain unpleasantness. Overall, the current study provides no support for the effectiveness of a single session ABM training in improving pain-related outcomes. Future research addressing the conditions under which ABM training improves or fails to improve pain-related outcomes is warranted.
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Affiliation(s)
- Dimitri M. L. Van Ryckeghem
- Institute for Health and Behaviour, INSIDE, University of Luxembourg, Esch-sur-Alzette, Luxembourg
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
- * E-mail:
| | - Stefaan Van Damme
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
| | - Tine Vervoort
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
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Klíma P, Laňková M, Vandenbussche F, Van Der Straeten D, Petrášek J. Silver ions increase plasma membrane permeability through modulation of intracellular calcium levels in tobacco BY-2 cells. Plant Cell Rep 2018; 37:809-818. [PMID: 29502206 DOI: 10.1007/s00299-018-2269-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 02/26/2018] [Indexed: 05/10/2023]
Abstract
KEY MESSAGE Silver ions increase plasma membrane permeability for water and small organic compounds through their stimulatory effect on plasma membrane calcium channels, with subsequent modulation of intracellular calcium levels and ion homeostasis. The action of silver ions at the plant plasma membrane is largely connected with the inhibition of ethylene signalling thanks to the ability of silver ion to replace the copper cofactor in the ethylene receptor. A link coupling the action of silver ions and cellular auxin efflux has been suggested earlier by their possible direct interaction with auxin efflux carriers or by influencing plasma membrane permeability. Using tobacco BY-2 cells, we demonstrate here that besides a dramatic increase of efflux of synthetic auxins 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthalene acetic acid (NAA), treatment with AgNO3 resulted in enhanced efflux of the cytokinin trans-zeatin (tZ) as well as the auxin structural analogues tryptophan (Trp) and benzoic acid (BA). The application of AgNO3 was accompanied by gradual water loss and plasmolysis. The observed effects were dependent on the availability of extracellular calcium ions (Ca2+) as shown by comparison of transport assays in Ca2+-rich and Ca2+-free buffers and upon treatment with inhibitors of plasma membrane Ca2+-permeable channels Al3+ and ruthenium red, both abolishing the effect of AgNO3. Confocal microscopy of Ca2+-sensitive fluorescence indicator Fluo-4FF, acetoxymethyl (AM) ester suggested that the extracellular Ca2+ availability is necessary to trigger the response to silver ions and that the intracellular Ca2+ pool alone is not sufficient for this effect. Altogether, our data suggest that in plant cells the effects of silver ions originate from the primal modification of the internal calcium levels, possibly by their interaction with Ca2+-permeable channels at the plasma membrane.
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Affiliation(s)
- Petr Klíma
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02, Prague 6, Czech Republic
| | - Martina Laňková
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02, Prague 6, Czech Republic
| | - Filip Vandenbussche
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K. L. Ledeganckstraat 35, Ghent, Belgium
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K. L. Ledeganckstraat 35, Ghent, Belgium
| | - Jan Petrášek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02, Prague 6, Czech Republic.
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic.
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Deleye L, Gansemans Y, De Coninck D, Van Nieuwerburgh F, Deforce D. Massively parallel sequencing of micro-manipulated cells targeting a comprehensive panel of disease-causing genes: A comparative evaluation of upstream whole-genome amplification methods. PLoS One 2018; 13:e0196334. [PMID: 29698522 PMCID: PMC5919401 DOI: 10.1371/journal.pone.0196334] [Citation(s) in RCA: 9] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/11/2018] [Indexed: 12/28/2022] Open
Abstract
Single Gene Disorders (SGD) are still routinely diagnosed using PCR-based assays that need to be developed and validated for each individual disease-specific gene fragment. The TruSight One sequencing panel currently covers 12 Mb of genomic content, including 4813 genes associated with a clinical phenotype. When only a limited number of cells are available, whole genome amplification (WGA) is required prior to DNA target capture techniques such as the TruSight One panel. In this study, we compared 4 different WGA methods in combination with the TruSight One sequencing panel to perform single nucleotide polymorphism (SNP) genotyping starting from 3 micro-manipulated cells. This setting simulates clinical settings such as day-5 blastocyst biopsy for Preimplantation Genetic Testing (PGT), liquid biopsy of circulating tumor cells (CTCs) and cancer-cell profiling. Bulk cell samples were processed alongside these WGA samples to serve as a performance reference. Target coverage, coverage uniformity and SNP calling accuracy obtained using any of the WGA, is inferior to the results obtained on bulk cell samples. However, results after REPLI-g come close. Compared to the other WGA methods, the method using REPLI-g WGA results in a better coverage of the targeted genomic regions with a more uniform read depth. Consequently, this method also results in a more accurate SNP calling and could be considered for clinical genotyping of a limited number of cells.
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Affiliation(s)
- Lieselot Deleye
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ghent, Belgium
| | - Yannick Gansemans
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ghent, Belgium
| | - Dieter De Coninck
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ghent, Belgium
| | | | - Dieter Deforce
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ghent, Belgium
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Vanlancker E, Vanhoecke B, Sieprath T, Bourgeois J, Beterams A, De Moerloose B, De Vos WH, Van de Wiele T. Oral microbiota reduce wound healing capacity of epithelial monolayers, irrespective of the presence of 5-fluorouracil. Exp Biol Med (Maywood) 2018; 243:350-360. [PMID: 29338309 PMCID: PMC6022929 DOI: 10.1177/1535370217753842] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 12/15/2017] [Indexed: 11/17/2022] Open
Abstract
Oral mucositis is still one of the most painful side effects of chemotherapeutic treatment and a mounting body of evidence suggests a key role for the oral microbiome in mucositis development. However, the underlying mechanisms remain elusive. In this work, we have investigated the interactions between the host, the microbiome, and chemotherapeutic treatments in more detail. The effect of 5-fluorouracil, commonly inducing mucositis, was assessed on a co-culture model that consists of an epithelial cell layer and a biofilm derived from oral microbiota from different types of samples (saliva, buccal swabs and tongue swabs) and donors (healthy individuals and patients suffering from mucositis). After 24 h co-incubation, all oral microbial samples were found to reduce wound healing capacity with 26 ± 15% as compared with untreated condition. Compared with saliva and tongue samples, buccal samples were characterized by lower bacterial cell counts and hence higher wound healing capacity. For samples from healthy individuals, an inverse correlation was observed between bacterial cell counts and wound healing capacity, whereas for patients suffering from mucositis no correlation was observed. Moreover, patient-derived samples had a less diverse microbial community and higher abundances of pathogenic genera. No major impact of 5-fluorouracil on wound healing capacity or the composition of the microbiome was seen at physiologically relevant concentrations in the mouth. In conclusion, bacterial cell count is inversely correlated with wound healing capacity, which emphasizes the importance of oral hygiene during oral wound healing in healthy individuals. However, future research on extra measures besides oral hygiene is needed to assure a good wound healing during mucositis, as for patients the bacterial composition seems also crucial. The direct effect of 5-fluorouracil on both the microbiome and wound healing is minimal, pointing to the importance of the host and its immune system in chemotherapy-induced microbial shifts. Impact statement Chemotherapy-induced oral mucositis has a major impact on the quality of life of patients. The additional costs and treatment time associated with this pathology are significant. Although the pathology of the disease is well understood, the role and importance of oral microbiota currently are less clear. In this study, we focused on the effect of oral microbiota on wound healing, the final phase of oral mucositis, during 5-FU exposure. We show that the bacterial load and composition have a major impact on the healing process in contrast to 5-FU which only marginally slows down healing. This emphasizes the importance of good oral health care during oral mucositis to minimize bacterial load around the oral lesions. However, since we show that also the composition of the oral microbiome plays a role in wound recovery, the identification of specific pathogenic species or their metabolites might be worthwhile to allow proper treatment.
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Affiliation(s)
- Eline Vanlancker
- Center for Microbial Ecology and Technology (CMET), Ghent University, Ghent 9000, Belgium
| | - Barbara Vanhoecke
- Center for Microbial Ecology and Technology (CMET), Ghent University, Ghent 9000, Belgium
| | - Tom Sieprath
- Cell Systems and Cellular Imaging Group, Department of Molecular Biotechnology, Ghent University, Ghent 9000, Belgium
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, Antwerp University, Antwerp 2610, Belgium
| | - Janie Bourgeois
- Center for Microbial Ecology and Technology (CMET), Ghent University, Ghent 9000, Belgium
| | - Annelore Beterams
- Center for Microbial Ecology and Technology (CMET), Ghent University, Ghent 9000, Belgium
| | - Barbara De Moerloose
- Department of Pediatric Hemato-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent 9000, Belgium
| | - Winnok H De Vos
- Cell Systems and Cellular Imaging Group, Department of Molecular Biotechnology, Ghent University, Ghent 9000, Belgium
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, Antwerp University, Antwerp 2610, Belgium
| | - Tom Van de Wiele
- Center for Microbial Ecology and Technology (CMET), Ghent University, Ghent 9000, Belgium
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Kalender Atak Z, Imrichova H, Svetlichnyy D, Hulselmans G, Christiaens V, Reumers J, Ceulemans H, Aerts S. Identification of cis-regulatory mutations generating de novo edges in personalized cancer gene regulatory networks. Genome Med 2017; 9:80. [PMID: 28854983 PMCID: PMC5575942 DOI: 10.1186/s13073-017-0464-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/02/2017] [Indexed: 01/05/2023] Open
Abstract
The identification of functional non-coding mutations is a key challenge in the field of genomics. Here we introduce μ-cisTarget to filter, annotate and prioritize cis-regulatory mutations based on their putative effect on the underlying "personal" gene regulatory network. We validated μ-cisTarget by re-analyzing the TAL1 and LMO1 enhancer mutations in T-ALL, and the TERT promoter mutation in melanoma. Next, we re-sequenced the full genomes of ten cancer cell lines and used matched transcriptome data and motif discovery to identify master regulators with de novo binding sites that result in the up-regulation of nearby oncogenic drivers. μ-cisTarget is available from http://mucistarget.aertslab.org .
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Affiliation(s)
- Zeynep Kalender Atak
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Hana Imrichova
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Dmitry Svetlichnyy
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Gert Hulselmans
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Valerie Christiaens
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Joke Reumers
- Discovery Sciences, Janssen Research & Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Hugo Ceulemans
- Discovery Sciences, Janssen Research & Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Stein Aerts
- Laboratory of Computational Biology, VIB Center for Brain & Disease Research, Leuven, Belgium.
- Department of Human Genetics, KU Leuven, Leuven, Belgium.
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Winckelmans E, Nawrot TS, Tsamou M, Den Hond E, Baeyens W, Kleinjans J, Lefebvre W, Van Larebeke N, Peusens M, Plusquin M, Reynders H, Schoeters G, Vanpoucke C, de Kok TM, Vrijens K. Transcriptome-wide analyses indicate mitochondrial responses to particulate air pollution exposure. Environ Health 2017; 16:87. [PMID: 28821289 PMCID: PMC5563023 DOI: 10.1186/s12940-017-0292-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Due to their lack of repair capacity mitochondria are critical targets for environmental toxicants. We studied genes and pathways reflecting mitochondrial responses to short- and medium-term PM10 exposure. METHODS Whole genome gene expression was measured in peripheral blood of 98 adults (49% women). We performed linear regression analyses stratified by sex and adjusted for individual and temporal characteristics to investigate alterations in gene expression induced by short-term (week before blood sampling) and medium-term (month before blood sampling) PM10 exposure. Overrepresentation analyses (ConsensusPathDB) were performed to identify enriched mitochondrial associated pathways and gene ontology sets. Thirteen Human MitoCarta genes were measured by means of quantitative real-time polymerase chain reaction (qPCR) along with mitochondrial DNA (mtDNA) content in an independent validation cohort (n = 169, 55.6% women). RESULTS Overrepresentation analyses revealed significant pathways (p-value <0.05) related to mitochondrial genome maintenance and apoptosis for short-term exposure and to the electron transport chain (ETC) for medium-term exposure in women. For men, medium-term PM10 exposure was associated with the Tri Carbonic Acid cycle. In an independent study population, we validated several ETC genes, including UQCRH and COX7C (q-value <0.05), and some genes crucial for the maintenance of the mitochondrial genome, including LONP1 (q-value: 0.07) and POLG (q-value: 0.04) in women. CONCLUSIONS In this exploratory study, we identified mitochondrial genes and pathways associated with particulate air pollution indicating upregulation of energy producing pathways as a potential mechanism to compensate for PM-induced mitochondrial damage.
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Affiliation(s)
- Ellen Winckelmans
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Tim S Nawrot
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
- Department of Public Health & Primary Care, Leuven University, Leuven, Belgium
| | - Maria Tsamou
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | | | - Willy Baeyens
- Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jos Kleinjans
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | | | - Nicolas Van Larebeke
- Department of Radiotherapy and Nuclear Medicine, Ghent University, Ghent, Belgium
| | - Martien Peusens
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Michelle Plusquin
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Hans Reynders
- Environment, Nature and Energy Department, Flemish Government, Brussels, Belgium
| | - Greet Schoeters
- Flemish Institute for Technological Research, Mol, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
- Institute of Public Health, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark
| | | | - Theo M de Kok
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - Karen Vrijens
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
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Winckelmans E, Vrijens K, Tsamou M, Janssen BG, Saenen ND, Roels HA, Kleinjans J, Lefebvre W, Vanpoucke C, de Kok TM, Nawrot TS. Newborn sex-specific transcriptome signatures and gestational exposure to fine particles: findings from the ENVIRONAGE birth cohort. Environ Health 2017; 16:52. [PMID: 28583124 PMCID: PMC5458481 DOI: 10.1186/s12940-017-0264-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/22/2017] [Indexed: 05/14/2023]
Abstract
BACKGROUND Air pollution exposure during pregnancy has been associated with adverse birth outcomes and health problems later in life. We investigated sex-specific transcriptomic responses to gestational long- and short-term exposure to particulate matter with a diameter < 2.5 μm (PM2.5) in order to elucidate potential underlying mechanisms of action. METHODS Whole genome gene expression was investigated in cord blood of 142 mother-newborn pairs that were enrolled in the ENVIRONAGE birth cohort. Daily PM2.5 exposure levels were calculated for each mother's home address using a spatial-temporal interpolation model in combination with a dispersion model to estimate both long- (annual average before delivery) and short- (last month of pregnancy) term exposure. We explored the association between gene expression levels and PM2.5 exposure, and identified modulated pathways by overrepresentation analysis and gene set enrichment analysis. RESULTS Some processes were altered in both sexes for long- (e.g. DNA damage) or short-term exposure (e.g. olfactory signaling). For long-term exposure in boys neurodevelopment and RhoA pathways were modulated, while in girls defensin expression was down-regulated. For short-term exposure we identified pathways related to synaptic transmission and mitochondrial function (boys) and immune response (girls). CONCLUSIONS This is the first whole genome gene expression study in cord blood to identify sex-specific pathways altered by PM2.5. The identified transcriptome pathways could provide new molecular insights as to the interaction pattern of early life PM2.5 exposure with the biological development of the fetus.
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Affiliation(s)
- Ellen Winckelmans
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Karen Vrijens
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Maria Tsamou
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Bram G. Janssen
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Nelly D. Saenen
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
| | - Harry A. Roels
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
- Louvain Centre for Toxicology and Applied Pharmacology (LTAP), Université catholique de Louvain, Brussels, Belgium
| | - Jos Kleinjans
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - Wouter Lefebvre
- Environmental Risk and Health, Flemish Institute for Technical Research (VITO), Mol, Belgium
| | | | - Theo M. de Kok
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - Tim S. Nawrot
- Centre for Environmental Sciences, Hasselt University, Agoralaan gebouw D, B-3590 Diepenbeek, Belgium
- Department of Public Health & Primary Care, Leuven University, Kapucijnenvoer 35, 3000 Leuven, Belgium
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Van Acker A, Louagie E, Filtjens J, Taveirne S, Van Ammel E, Kerre T, Elewaut D, Taghon T, Vandekerckhove B, Plum J, Leclercq G. The role of Ly49E receptor expression on murine intraepithelial lymphocytes in intestinal cancer development and progression. Cancer Immunol Immunother 2016; 65:1365-1375. [PMID: 27585789 PMCID: PMC11029008 DOI: 10.1007/s00262-016-1894-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 08/26/2016] [Indexed: 01/04/2023]
Abstract
Ly49E is a member of the Ly49 family of NK receptors and is distinct from other members of this family on the basis of its structural properties, expression pattern and ligand recognition. Importantly, Ly49E receptor expression is high on small intestinal and colonic intraepithelial lymphocytes (IELs). Intestinal IELs are regulators of the mucosal immune system and contribute to front-line defense at the mucosal barrier, including anti-tumor immune response. Whereas most Ly49 receptors have MHC class-I ligands, we showed that Ly49E is instead triggered by urokinase plasminogen activator (uPA). uPA has been extensively implicated in tumor development, where increased uPA expression correlates with poor prognosis. As such, we investigated the role of Ly49E receptor expression on intestinal IELs in the anti-tumor immune response. For this purpose, we compared Ly49E wild-type mice to Ly49E knockout mice in two established tumor models: ApcMin/+-mediated and azoxymethane-induced intestinal cancer. Our results indicate that Ly49E expression on IELs does not influence the development or progression of intestinal cancer.
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Affiliation(s)
- Aline Van Acker
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Els Louagie
- Department of Rheumatology, Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - Jessica Filtjens
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Sylvie Taveirne
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Els Van Ammel
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Tessa Kerre
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Dirk Elewaut
- Department of Rheumatology, Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - Tom Taghon
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Bart Vandekerckhove
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Jean Plum
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Georges Leclercq
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium.
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Stock E, Vanderperren K, Bosmans T, Dobbeleir A, Duchateau L, Hesta M, Lybaert L, Peremans K, Vandermeulen E, Saunders J. Evaluation of Feline Renal Perfusion with Contrast-Enhanced Ultrasonography and Scintigraphy. PLoS One 2016; 11:e0164488. [PMID: 27736928 PMCID: PMC5063434 DOI: 10.1371/journal.pone.0164488] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 09/26/2016] [Indexed: 01/27/2023] Open
Abstract
Contrast-enhanced ultrasound (CEUS) is an emerging technique to evaluate tissue perfusion. Promising results have been obtained in the evaluation of renal perfusion in health and disease, both in human and veterinary medicine. Renal scintigraphy using 99mTc-Mercaptoacetyltriglycine (MAG3) is another non-invasive technique that can be used to evaluate renal perfusion. However, no data are available on the ability of CEUS or 99mTc- MAG3 scintigraphy to detect small changes in renal perfusion in cats. Therefore, both techniques were applied in a normal feline population to evaluate detection possibilities of perfusion changes by angiotensin II (AT II). Contrast-enhanced ultrasound using a bolus injection of commercially available contrast agent and renal scintigraphy using 99mTc-MAG3 were performed in 11 healthy cats after infusion of 0,9% NaCl (control) and AT II. Angiotensin II induced changes were noticed on several CEUS parameters. Mean peak enhancement, wash-in perfusion index and wash-out rate for the entire kidney decreased significantly after AT II infusion. Moreover, a tendency towards a lower wash-in area-under-the curve was present. Renal scintigraphy could not detect perfusion changes induced by AT II. This study shows that CEUS is able to detect changes in feline renal perfusion induced by AT II infusion.
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Affiliation(s)
- Emmelie Stock
- Department of Medical Imaging of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
- * E-mail:
| | - Katrien Vanderperren
- Department of Medical Imaging of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - Tim Bosmans
- Department of Medicine and Clinical Biology of Small Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - André Dobbeleir
- Ghent University Hospital, Department of Radiology and Nuclear Medicine, De Pintelaan 185, 9000 Ghent, Belgium
| | - Luc Duchateau
- Department of Comparative Physiology and Biometry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - Myriam Hesta
- Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - Lien Lybaert
- Lab of Pharmaceutical technology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, Ghent, Belgium
| | - Kathelijne Peremans
- Department of Medical Imaging of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - Eva Vandermeulen
- Department of Medical Imaging of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
| | - Jimmy Saunders
- Department of Medical Imaging of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, Belgium
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Nijhof AD, Brass M, Bardi L, Wiersema JR. Measuring Mentalizing Ability: A Within-Subject Comparison between an Explicit and Implicit Version of a Ball Detection Task. PLoS One 2016; 11:e0164373. [PMID: 27723814 PMCID: PMC5056736 DOI: 10.1371/journal.pone.0164373] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 09/23/2016] [Indexed: 12/02/2022] Open
Abstract
The concept of mentalizing has been widely studied, but almost exclusively through tasks with explicit instructions. Recent studies suggest that people also mentalize on a more implicit level. However, to our knowledge, no study to date has directly contrasted the effects of implicit and explicit mentalizing processes on an implicit dependent measure within-subjects. We implemented this by using two versions of an object detection task, differing only on secondary catch questions. We hypothesized that if explicit mentalizing relies on complementary processes beyond those underlying implicit mentalizing, this would be reflected in enhanced belief effects in the explicit version. Twenty-eight healthy adults watched movies in which, during the first phase, both they themselves and another agent formed a belief about the location of a ball, and although irrelevant, these beliefs could influence their ball detection reaction times in the second phase. After this response phase, there were occasional catch questions that were different for the explicit and implicit task version. Finally, self-report measures of autism spectrum disorder (ASD) symptomatology were included, as the literature suggests that ASD is related to a specific deficit in implicit mentalizing. Both in the explicit and implicit version, belief conditions had a significant effect on reaction times, with responses being slower when neither the participant nor the other agent expected the ball to be present compared to all other conditions. Importantly, after the implicit version, participants reported no explicit mentalizing awareness. In our neurotypical sample, ASD symptoms were not found to correlate with either explicit or implicit mentalizing. In conclusion, the reaction time patterns in the explicit and implicit version of the task show strikingly similar effects of mentalizing, indicating that participants processed beliefs to the same extent regardless of whether they mentalized explicitly or implicitly, with no additional effects for explicit processing.
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Larsen LE, Wadman WJ, Marinazzo D, van Mierlo P, Delbeke J, Daelemans S, Sprengers M, Thyrion L, Van Lysebettens W, Carrette E, Boon P, Vonck K, Raedt R. Vagus Nerve Stimulation Applied with a Rapid Cycle Has More Profound Influence on Hippocampal Electrophysiology Than a Standard Cycle. Neurotherapeutics 2016; 13:592-602. [PMID: 27102987 PMCID: PMC4965402 DOI: 10.1007/s13311-016-0432-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Although vagus nerve stimulation (VNS) is widely used, therapeutic mechanisms and optimal stimulation parameters remain elusive. In the present study, we investigated the effect of VNS on hippocampal field activity and compared the efficiency of different VNS paradigms. Hippocampal electroencephalography (EEG) and perforant path dentate field-evoked potentials were acquired before and during VNS in freely moving rats, using 2 VNS duty cycles: a rapid cycle (7 s on, 18 s off) and standard cycle (30 s on, 300 s off) and various output currents. VNS modulated the evoked potentials, reduced total power of the hippocampal EEG, and slowed the theta rhythm. In the hippocampal EEG, theta (4-8 Hz) and high gamma (75-150 Hz) activity displayed strong phase amplitude coupling that was reduced by VNS. Rapid-cycle VNS had a greater effect than standard-cycle VNS on all outcome measures. Using rapid cycle VNS, a maximal effect on EEG parameters was found at 300 μA, beyond which effects saturated. The findings suggest that rapid-cycle VNS produces a more robust outcome than standard cycle VNS and support already existing preclinical evidence that relatively low output currents are sufficient to produce changes in brain physiology and thus likely also therapeutic efficacy.
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Affiliation(s)
- Lars E Larsen
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium.
| | - Wytse J Wadman
- Swammerdam Institute of Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Daniele Marinazzo
- Department of Data Analysis, Faculty for Psychological and Pedagogical Sciences, Ghent University, Ghent, Belgium
| | - Pieter van Mierlo
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
- Medical Imaging and Signal Processing, Department of Electronics and Information Systems, iMinds Medical IT Department, Ghent University, Ghent, Belgium
| | - Jean Delbeke
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Sofie Daelemans
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Mathieu Sprengers
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Lisa Thyrion
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Wouter Van Lysebettens
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Evelien Carrette
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Paul Boon
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Kristl Vonck
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
| | - Robrecht Raedt
- Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Ghent, Belgium
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Akbarian A, Michiels J, Degroote J, Majdeddin M, Golian A, De Smet S. Association between heat stress and oxidative stress in poultry; mitochondrial dysfunction and dietary interventions with phytochemicals. J Anim Sci Biotechnol 2016; 7:37. [PMID: 27354915 PMCID: PMC4924307 DOI: 10.1186/s40104-016-0097-5] [Citation(s) in RCA: 271] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 06/15/2016] [Indexed: 11/10/2022] Open
Abstract
Heat as a stressor of poultry has been studied extensively for many decades; it affects poultry production on a worldwide basis and has significant impact on well-being and production. More recently, the involvement of heat stress in inducing oxidative stress has received much interest. Oxidative stress is defined as the presence of reactive species in excess of the available antioxidant capacity of animal cells. Reactive species can modify several biologically cellular macromolecules and can interfere with cell signaling pathways. Furthermore, during the last decade, there has been an ever-increasing interest in the use of a wide array of natural feed-delivered phytochemicals that have potential antioxidant properties for poultry. In light of this, the current review aims to (1) summarize the mechanisms through which heat stress triggers excessive superoxide radical production in the mitochondrion and progresses into oxidative stress, (2) illustrate that this pathophysiology is dependent on the intensity and duration of heat stress, (3) present different nutritional strategies for mitigation of mitochondrial dysfunction, with particular focus on antioxidant phytochemicals. Oxidative stress that occurs with heat exposure can be manifest in all parts of the body; however, mitochondrial dysfunction underlies oxidative stress. In the initial phase of acute heat stress, mitochondrial substrate oxidation and electron transport chain activity are increased resulting in excessive superoxide production. During the later stage of acute heat stress, down-regulation of avian uncoupling protein worsens the oxidative stress situation causing mitochondrial dysfunction and tissue damage. Typically, antioxidant enzyme activities are upregulated. Chronic heat stress, however, leads to downsizing of mitochondrial metabolic oxidative capacity, up-regulation of avian uncoupling protein, a clear alteration in the pattern of antioxidant enzyme activities, and depletion of antioxidant reserves. Some phytochemicals, such as various types of flavonoids and related compounds, were shown to be beneficial in chronic heat-stressed poultry, but were less or not effective in non-heat-stressed counterparts. This supports the contention that antioxidant phytochemicals have potential under challenging conditions. Though substantial progress has been made in our understanding of the association between heat stress and oxidative stress, the means by which phytochemicals can alleviate oxidative stress have been sparsely explored.
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Affiliation(s)
- Abdollah Akbarian
- />Department of Animal Production, Laboratory for Animal Nutrition and Animal Product Quality, Ghent University, Proefhoevestraat 10, Melle, 9090 Belgium
- />Centre of Excellence in the Animal Science Department, Ferdowsi University of Mashhad, P.O. Box: 91775–1163, Mashhad, Iran
| | - Joris Michiels
- />Department of Applied Biosciences, Ghent University, Valentin Vaerwyckweg 1, Ghent, 9000 Belgium
| | - Jeroen Degroote
- />Department of Applied Biosciences, Ghent University, Valentin Vaerwyckweg 1, Ghent, 9000 Belgium
| | - Maryam Majdeddin
- />Department of Animal Production, Laboratory for Animal Nutrition and Animal Product Quality, Ghent University, Proefhoevestraat 10, Melle, 9090 Belgium
- />Centre of Excellence in the Animal Science Department, Ferdowsi University of Mashhad, P.O. Box: 91775–1163, Mashhad, Iran
- />Department of Applied Biosciences, Ghent University, Valentin Vaerwyckweg 1, Ghent, 9000 Belgium
| | - Abolghasem Golian
- />Centre of Excellence in the Animal Science Department, Ferdowsi University of Mashhad, P.O. Box: 91775–1163, Mashhad, Iran
| | - Stefaan De Smet
- />Department of Animal Production, Laboratory for Animal Nutrition and Animal Product Quality, Ghent University, Proefhoevestraat 10, Melle, 9090 Belgium
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Vervoort G, Leunissen I, Firbank M, Heremans E, Nackaerts E, Vandenberghe W, Nieuwboer A. Structural Brain Alterations in Motor Subtypes of Parkinson's Disease: Evidence from Probabilistic Tractography and Shape Analysis. PLoS One 2016; 11:e0157743. [PMID: 27314952 PMCID: PMC4912098 DOI: 10.1371/journal.pone.0157743] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/05/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND OBJECTIVES The postural instability and gait disorder (PIGD) and tremor dominant (TD) subtypes of Parkinson's disease (PD) show different patterns of alterations in functional connectivity (FC) between specific brain regions. This study aimed to investigate the relation between symptomatic heterogeneity in PD and structural alterations underlying these FC changes. METHODS 68 PD patients classified as PIGD (n = 41) or TD (n = 19) and 19 age-matched controls underwent Magnetic Resonance Imaging (MRI). Diffusion-weighted images were used to assess fractional anisotropy (FA) and mean diffusivity (MD) at the whole-brain level using tract-based spatial statistics (TBSS). In addition, structural connectivity was assessed between regions that previously showed altered FC using probabilistic tractography. Anatomical images were used to determine shape and volume of the putamen, caudate and pallidum. RESULTS TBSS revealed widespread FA reductions in PIGD compared to controls involving the superior longitudinal fasciculi and corpus callosum. No such differences were found in TD. Both PD subgroups had increased MD compared to controls in tracts connecting the left caudate with the bilateral ventral putamen. TD patients additionally showed increased MD compared to PIGD and controls in tracts connecting the right inferior parietal lobule with the right premotor and primary motor cortex, which previously showed altered FC. We also found grey matter atrophy in the rostrodorsal head of the caudate in PIGD compared to controls. CONCLUSION Microstructural changes in white matter tracts, particularly in those connecting striatal sub-areas, partly underlie FC alterations in PD subtypes. Caudate shape alterations further implicate the striatum in PIGD pathophysiology.
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Affiliation(s)
- Griet Vervoort
- KU Leuven, Department of Rehabilitation Sciences, Tervuursevest 101/1501, 3001, Leuven, Belgium
- * E-mail:
| | - Inge Leunissen
- KU Leuven, Department of Kinesiology, Tervuursevest 101/1501, 3001, Leuven, Belgium
| | - Michael Firbank
- Institute of Neuroscience and Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, NE4 5PL, United Kingdom
| | - Elke Heremans
- KU Leuven, Department of Rehabilitation Sciences, Tervuursevest 101/1501, 3001, Leuven, Belgium
| | - Evelien Nackaerts
- KU Leuven, Department of Rehabilitation Sciences, Tervuursevest 101/1501, 3001, Leuven, Belgium
| | - Wim Vandenberghe
- University Hospitals Leuven, Department of Neurology, Herestraat 49, 3000 Leuven, Belgium; KU Leuven, Department of Neurosciences, Herestraat 49, 3000, Leuven, Belgium
| | - Alice Nieuwboer
- KU Leuven, Department of Rehabilitation Sciences, Tervuursevest 101/1501, 3001, Leuven, Belgium
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80
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Devlamynck T, Te Poele EM, Meng X, van Leeuwen SS, Dijkhuizen L. Glucansucrase Gtf180-ΔN of Lactobacillus reuteri 180: enzyme and reaction engineering for improved glycosylation of non-carbohydrate molecules. Appl Microbiol Biotechnol 2016; 100:7529-39. [PMID: 27052379 PMCID: PMC4980424 DOI: 10.1007/s00253-016-7476-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 03/08/2016] [Accepted: 03/15/2016] [Indexed: 12/24/2022]
Abstract
Glucansucrases have a broad acceptor substrate specificity and receive increased attention as biocatalysts for the glycosylation of small non-carbohydrate molecules using sucrose as donor substrate. However, the main glucansucrase-catalyzed reaction results in synthesis of α-glucan polysaccharides from sucrose, and this strongly impedes the efficient glycosylation of non-carbohydrate molecules and complicates downstream processing of glucosylated products. This paper reports that suppressing α-glucan synthesis by mutational engineering of the Gtf180-ΔN enzyme of Lactobacillus reuteri 180 results in the construction of more efficient glycosylation biocatalysts. Gtf180-ΔN mutants (L938F, L981A, and N1029M) with an impaired α-glucan synthesis displayed a substantial increase in monoglycosylation yields for several phenolic and alcoholic compounds. Kinetic analysis revealed that these mutants possess a higher affinity for the model acceptor substrate catechol but a lower affinity for its mono-α-d-glucoside product, explaining the improved monoglycosylation yields. Analysis of the available high resolution 3D crystal structure of the Gtf180-ΔN protein provided a clear understanding of how mutagenesis of residues L938, L981, and N1029 impaired α-glucan synthesis, thus yielding mutants with an improved glycosylation potential.
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Affiliation(s)
- Tim Devlamynck
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
- Centre for Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Evelien M Te Poele
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Xiangfeng Meng
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Sander S van Leeuwen
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Lubbert Dijkhuizen
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands.
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