90 results on '"Dudhia J"'
Search Results
2. CONUS404: The NCAR–USGS 4-km Long-Term Regional Hydroclimate Reanalysis over the CONUS
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Rasmussen, R. M., primary, Chen, F., additional, Liu, C.H., additional, Ikeda, K., additional, Prein, A., additional, Kim, J., additional, Schneider, T., additional, Dai, A., additional, Gochis, D., additional, Dugger, A., additional, Zhang, Y., additional, Jaye, A., additional, Dudhia, J., additional, He, C., additional, Harrold, M., additional, Xue, L., additional, Chen, S., additional, Newman, A., additional, Dougherty, E., additional, Abolafia-Rosenzweig, R., additional, Lybarger, N. D., additional, Viger, R., additional, Lesmes, D., additional, Skalak, K., additional, Brakebill, J., additional, Cline, D., additional, Dunne, K., additional, Rasmussen, K., additional, and Miguez-Macho, G., additional
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- 2023
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3. An evaluation of WRF's ability to reproduce the surface wind over complex terrain based on typical circulation patterns
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Jiménez, P. A., Dudhia, J., González Rouco, J. Fidel, Montávez, J. P., García Bustamante, E., Navarro, J., Vilà-Guerau de Arellano, J., Múñoz Roldán, A., Jiménez, P. A., Dudhia, J., González Rouco, J. Fidel, Montávez, J. P., García Bustamante, E., Navarro, J., Vilà-Guerau de Arellano, J., and Múñoz Roldán, A.
- Abstract
© 2013. American Geophysical Union. All Rights Reserved. This investigation was partially supported by projects CGL-2008-05093/CLI and CGL-2011-29677-C02 and was accomplished within the collaboration agreement 09/490 between CIEMAT and NCAR as well as the collaboration agreement 09/153 between CIEMAT and UCM. NCAR is sponsored by the National Science Foundation. We would like to thank the Navarra government and the ECMWF for facilitating the access to its data sets. We also would like to thank the reviewers for their constructive comments which helped to increase the value of the contents of the manuscript., The performance of the Weather Research and Forecasting (WRF) model to reproduce the surface wind circulations over complex terrain is examined. The atmospheric evolution is simulated using two versions of the WRF model during an over 13year period (1992 to 2005) over a complex terrain region located in the northeast of the Iberian Peninsula. A high horizontal resolution of 2km is used to provide an accurate representation of the terrain features. The multiyear evaluation focuses on the analysis of the accuracy displayed by the WRF simulations to reproduce the wind field of the six typical wind patterns (WPs) identified over the area in a previous observational work. Each pattern contains a high number of days which allows one to reach solid conclusions regarding the model performance. The accuracy of the simulations to reproduce the wind field under representative synoptic situations, or pressure patterns (PPs), of the Iberian Peninsula is also inspected in order to diagnose errors as a function of the large-scale situation. The evaluation is accomplished using daily averages in order to inspect the ability of WRF to reproduce the surface flow as a result of the interaction between the synoptic scale and the regional topography. Results indicate that model errors can originate from problems in the initial and lateral boundary conditions, misrepresentations at the synoptic scale, or the realism of the topographic features., Ministerio de Economía y Competitividad (MINECO), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), España, National Center for Atmospheric Research (NCAR), Universidad Complutense de Madrid (UCM), National Science Foundation (NSF), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub
- Published
- 2023
4. CONUS404 The NCAR–USGS 4-km Long-Term Regional Hydroclimate Reanalysis over the CONUS
- Author
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Rasmussen, R.M., Chen, F., Liu, C.H., Ikeda, K., Prein, A., Kim, J., Schneider, T., Dai, A., Gochis, D., Dugger, A., Zhang, Y., Jaye, A., Dudhia, J., He, C., Harrold, M., Xue, L., Chen, S., Newman, A., Dougherty, E., Abolafia-Rosenzweig, R., Lybarger, N.D., Viger, R., Lesmes, D., Skalak, K., Brakebill, J., Cline, D., Dunne, K., Rasmussen, K., Miguez-Macho, G., Rasmussen, R.M., Chen, F., Liu, C.H., Ikeda, K., Prein, A., Kim, J., Schneider, T., Dai, A., Gochis, D., Dugger, A., Zhang, Y., Jaye, A., Dudhia, J., He, C., Harrold, M., Xue, L., Chen, S., Newman, A., Dougherty, E., Abolafia-Rosenzweig, R., Lybarger, N.D., Viger, R., Lesmes, D., Skalak, K., Brakebill, J., Cline, D., Dunne, K., Rasmussen, K., and Miguez-Macho, G.
- Abstract
A unique, high-resolution, hydroclimate reanalysis, 40-plus-year (October 1979–September 2021), 4 km (named as CONUS404), has been created using the Weather Research and Forecasting Model by dynamically downscaling of the fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis of the global climate dataset (ERA5) over the conterminous United States. The paper describes the approach for generating the dataset, provides an initial evaluation, including biases, and indicates how interested users can access the data. The motivation for creating this National Center for Atmospheric Research (NCAR)–U.S. Geological Survey (USGS) collaborative dataset is to provide research and end-user communities with a high-resolution, self-consistent, long-term, continental-scale hydroclimate dataset appropriate for forcing hydrological models and conducting hydroclimate scientific analyses over the conterminous United States. The data are archived and accessible on the USGS Black Pearl tape system and on the NCAR supercomputer Campaign storage system. © 2023 American Meteorological Society.
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- 2023
5. A new double moment bulk microphysics parameterization scheme with in-cloud processes
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Hong, S., Li, H., Bao, J., and Dudhia, J.
- Abstract
A new double-moment bulk microphysics parameterization with in-cloud microphysical processes is developed for use in weather forecasting and climate studies. A main ingredient of the scheme utilizes a concept to represent the partial cloudiness effect on the microphysical processes, following the study of Kim and Hong (2018). The underlying assumption is that all the microphysical processes occur in a cloudy part of the grid box. Based on the long-term evaluation of the WRF Single-Moment (WSM) and WRF Double-Moment (WDM) schemes by WRF community, several revisions are made in microphysics terms, along with a newly introduced aerosol effect in ice processes. An aerosol-aware feature with prognostic aerosol emissions of sea salt, dust, anthropogenic and wildfire organic carbon for CCN is also designed.A mass-conserving Semi-Lagrangian sedimentation is re-configured for double-moment physics, which is superior to the conventional Eulerian algorithm in the context of the computational accuracy and numerical accuracy. The scheme is to be evaluated in WRF and UFS models., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)
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- 2023
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6. Expression of Sulf1 and Sulf2 in cartilage, bone and endochondral fracture healing
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Zaman, G., Staines, K. A., Farquharson, C., Newton, P. T., Dudhia, J., Chenu, C., Pitsillides, A. A., and Dhoot, G. K.
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- 2016
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7. Intra-operative Raman spectroscopy and mapping for assessment of cartilage degradation
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Gaifulina, R., Nunn, A.D.G., Draper, E., Strachan, R.K., Blake, N., Thomas, G.M.H., McMillan, P.F., and Dudhia, J.
- Abstract
The development of a label-free, non-destructive and safe analytical method such as Raman spectroscopy for assessing cartilage degradation is highly desirable. Compared to non-optical imaging modalities, Raman mapping offers a more sensitive means of directly assessing the chemical composition of cartilage in three-dimensional space and the potential to monitor cartilage degeneration to inform intervention and treatment strategies. Herein, we report the application of Raman spectroscopic methods ex vivo and at arthroscopy to identify molecular alterations in cartilage specimens containing minor focal lesions characteristic of the early disease phase. Our initial ex vivo analysis, obtained by single-point Raman spectroscopy of cartilage samples, supports previous findings based on S-O stretching vibration bands associated with sulphated glycosaminoglycans (sGAGs). We extended the analyses to the high-wavenumber region where we observed that vibrational bands assigned to C-H and O-H stretching modes discriminated early cartilage alterations from healthy cartilage samples. Furthermore, we performed a proof-of-concept in-clinic study using a custom-built optical probe to acquire Raman spectral measurements for the first time in patients undergoing arthroscopy of knee joints. Spectra were obtained with adequate signal-to-noise ratios that similarly discriminated between lesion and adjacent cartilage sites and identified reductions in sGAGs in apparently healthy cartilage. Building on this, we present initial results from Raman mapping to spatially resolve the molecular constituents of cartilage through its depth and across a lesion. Mapping revealed a non-uniform and reduced sGAG distribution within the lesion and peripheral cartilage that was otherwise visually normal, similar to the in-clinic observations, showing that the degradative influence of the lesion extended beyond its border. This was accompanied by a decreased fluorescence signal intensity, which suggests that fluorescence may provide valuable information as an adjunct to the Raman signal in discriminating normal and degenerating cartilage. This work demonstrates the value of Raman mapping over single-point Raman measurements for the analysis of the anisotropy of articular cartilage and highlights the potential of the technology for in vivo articular joint arthroscopy applications.
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- 2021
8. Large Animal Models in Regenerative Medicine and Tissue Engineering: To Do or Not to Do
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Ribitsch, I., Baptista, P.M., Lange-Consiglio, A., Melotti, L., Patruno, M., Jenner, F., Schnabl-Feichter, E., Dutton, L.C., Connolly, D.J., van Steenbeek, F.G., Dudhia, J., and Penning, L.C.
- Abstract
Rapid developments in Regenerative Medicine and Tissue Engineering has witnessed an increasing drive toward clinical translation of breakthrough technologies. However, the progression of promising preclinical data to achieve successful clinical market authorisation remains a bottleneck. One hurdle for progress to the clinic is the transition from small animal research to advanced preclinical studies in large animals to test safety and efficacy of products. Notwithstanding this, to draw meaningful and reliable conclusions from animal experiments it is critical that the species and disease model of choice is relevant to answer the research question as well as the clinical problem. Selecting the most appropriate animal model requires in-depth knowledge of specific species and breeds to ascertain the adequacy of the model and outcome measures that closely mirror the clinical situation. Traditional reductionist approaches in animal experiments, which often do not sufficiently reflect the studied disease, are still the norm and can result in a disconnect in outcomes observed between animal studies and clinical trials. To address these concerns a reconsideration in approach will be required. This should include a stepwise approach using in vitro and ex vivo experiments as well as in silico modeling to minimize the need for in vivo studies for screening and early development studies, followed by large animal models which more closely resemble human disease. Naturally occurring, or spontaneous diseases in large animals remain a largely untapped resource, and given the similarities in pathophysiology to humans they not only allow for studying new treatment strategies but also disease etiology and prevention. Naturally occurring disease models, particularly for longer lived large animal species, allow for studying disorders at an age when the disease is most prevalent. As these diseases are usually also a concern in the chosen veterinary species they would be beneficiaries of newly developed therapies. Improved awareness of the progress in animal models is mutually beneficial for animals, researchers, human and veterinary patients. In this overview we describe advantages and disadvantages of various animal models including domesticated and companion animals used in regenerative medicine and tissue engineering to provide an informed choice of disease-relevant animal models.
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- 2020
9. WRF‐TEB: Implementation and Evaluation of the Coupled Weather Research and Forecasting (WRF) and Town Energy Balance (TEB) Model
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Meyer, D., primary, Schoetter, R., additional, Riechert, M., additional, Verrelle, A., additional, Tewari, M., additional, Dudhia, J., additional, Masson, V., additional, van Reeuwijk, M., additional, and Grimmond, S., additional
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- 2020
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10. Science‐in‐brief: The importance of senescence in tendinopathy: New opportunities
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Kelly, E., primary, Smith, R., additional, Dudhia, J., additional, and Faragher, R. G. A., additional
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- 2020
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11. Probabilistic Forecast of All-Sky Solar Radiation Using Enhanced WRF-Solar
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Kim, J.-H., Jimenez, P.A., Dudhia, J., Yang, J., Sengupta, M., and Xie, Y.
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PV Systems and Storage – Modelling, Design, Operation and Performance ,Solar Resource and Forecasting - Abstract
37th European Photovoltaic Solar Energy Conference and Exhibition; 1247-1249, This study presents enhancements of the Weather Research and Forecasting model with solar extensions (WRFSolar) to provide probabilistic forecasts of solar radiation. Our approach builds ensemble WRF-Solar runs by introducing stochastic perturbations of variables that produce the largest uncertainties in predicting surface irradiance and clouds. The key variables are identified using tangent linear sensitivity analysis of six physics packages responsible for all-sky irradiance variability. An optimal strategy to stochastically perturb the selected variables is developed and applied to WRF-Solar to generate ensemble members for day-ahead solar prediction. The National Solar Radiation Database (NSRDB) is used to validate the ensemble forecast at arbitrary locations on the model grid. Preliminary results indicate that the proposed technique can potentially produce WRF-Solar ensembles providing reliable information of solar prediction uncertainty. This study describes the implemented methodology and initial results as well as future research to improve ensemble-based probabilistic forecasts with WRF-Solar.
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- 2020
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12. Inducing pluripotency in the domestic cat (Felis Catus)
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Dutton, L C, Dudhia, J, Guest, D J, and Connolly, D J
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embryonic structures - Abstract
Domestic cats suffer from a range of inherited genetic diseases, many of which display similarities with equivalent human conditions. Developing cellular models for these inherited diseases would enable drug discovery, benefiting feline health and welfare as well as enhancing the potential of cats as relevant animal models for translation to human medicine. Advances in our understanding of these diseases at the cellular level have come from the use of induced pluripotent stem cells (iPSCs). iPSCs are capable of differentiating into derivatives of all three germ layers, therefore overcoming the limitations of primary differentiated cells and the ethical concerns of using embryonic stem cells. No studies however report the generation of iPSCs from domestic cats (fiPSCs). Feline adipose derived fibroblasts were infected with amphotropic retrovirus containing the coding sequences for human Oct4, Sox2, Klf4, cMyc and Nanog. Isolated iPSC clones were expanded on mouse inactivated embryonic fibroblasts in the presence of feline leukaemia inhibitory factor (LIF). Retroviral delivery of human pluripotent genes gave rise to putative fiPSC colonies within 5-7 days. These iPS-like cells required foetal bovine serum and feline LIF for maintenance. Colonies were domed with refractile edges, similar to mouse iPSCs. Immunocytochemistry demonstrated positive staining for stem cell markers: alkaline phosphatase, Oct4, Sox2, Nanog and SSEA1. Cells were negative for SSEA4. Expression of endogenous feline Nanog was confirmed by qPCR. The cells were able to differentiate in vitro into cells representative of the three germ layers. These results confirm the generation of the first induced pluripotent cells from domestic cats. These cells will provide valuable models to study genetic diseases and explore novel therapeutic strategies.
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- 2019
13. Inhibition of LRP1 shedding reverses cartilage matrix degradation in osteoarthritis
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Yamamoto, K, Santamaria, S, Botkjaer, K, Dudhia, J, Troeberg, L, Itoh, Y, Murphy, G, and Nagase, H
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- 2018
14. Cryopreservation of canine cardiosphere-derived cells: Implications for clinical application
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Dutton, L C, Church, S A V, Hodgkiss-Geere, H, Catchpole, B, Huggins, A, Dudhia, J, and Connolly, D J
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- 2018
15. Exploring the convective grey zone with regional simulations of a cold air outbreak
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Field, PR, Brožková, R, Chen, M, Dudhia, J, Lac, C, Hara, T, Honnert, R, Olson, J, Siebesma, P, de Roode, S, Tomassini, L, Hill, A, and McTagart-Cowan, R
- Abstract
Cold air outbreaks can bring snow to populated areas and can affect aviation safety. Shortcomings in the representation of these phenomena in global and regional models are thought to be associated with large systematic cloud related radiative flux errors across many models. In this study, nine regional models have been used to simulate a cold air outbreak case at a range of grid spacings (1 km to 16 km) with convection represented explicitly or by a parametrization. Overall, there is more spread between model results for the simulations in which convection is parametrized when compared to simulations in which convection is represented explicitly. The quality of the simulations of both the stratocumulus and the convective regions of the domain are assessed with observational comparisons 24 hours into the simulation. The stratocumulus region is not well reproduced by the models, which tend to predict open cell convection with increasing resolution rather than stratocumulus. For the convective region the model spread reduces with increased resolution and there is some improvement in comparison to observations. Comparing models that have the same physical parametrizations or dynamical core suggest that both are important for accurately reproducing this case.
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- 2017
16. Influence of commonly used pharmaceutical agents on equine bone marrow-derived mesenchymal stem cell viability
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Edmonds, R E, Garvican, E R, Smith, R K W, and Dudhia, J
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- 2017
17. Structural changes in cartilage and collagen studied by high temperature Raman spectroscopy
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Fields, M, Spencer, N, Dudhia, J, and McMillan, P F
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sense organs ,skin and connective tissue diseases - Published
- 2017
18. Inhibition of LRP1 shedding reverses cartilage degradation in osteoarthritis
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Yamamoto, K., primary, Scavenius, C., additional, Santamaria, S., additional, Botkjaer, K.A., additional, Dudhia, J., additional, Troeberg, L., additional, Itoh, Y., additional, Murphy, G., additional, Enghild, J.J., additional, and Nagase, H., additional
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- 2018
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19. The use of a numerical weather prediction model to simulate the release of a dense gas with an application to the Lake Nyos disaster of 1986
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Burton, RR, Dudhia, J, Gadian, AM, and Mobbs, SD
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Physics::Atmospheric and Oceanic Physics - Abstract
The spread of a dense gas in the atmosphere is a phenomenon that occurs widely with natural (and anthropogenic) causes and is often associated with high impact and hazardous events. In this study a method of simulating the spread of dense gases in a numerical weather prediction model is presented. This approach has the advantage that dense gases can be simulated in regions of complex terrain using realistic forcings (in terms of both the driving meteorological fields and the representation of surface characteristics). The model formulation is tested against semi-idealized gravity-current-type experiments and similar modelling studies. As an example application, the Lake Nyos disaster of 1986, where a dense CO2 cloud spread through a mountainous region of Cameroon, is simulated. The predicted spread of CO2 agrees (qualitatively) very well with the observations. The method provides a means of determining a potential ‘safe height’ above which simulated concentrations are not hazardous, and thus the height above which refuge should be taken during similar future events. The simulation demonstrates a novel application which can be rapidly applied to other scenarios.
- Published
- 2016
20. Exposure of a tendon extracellular matrix to synovial fluid triggers endogenous and engrafted cell death: A mechanism for failed healing of intrathecal tendon injuries
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Garvican, E R, Salavati, M, Smith, R K W, and Dudhia, J
- Abstract
Aim: The purpose of this study was to investigate the effect of normal synovial fluid (SF) on exposed endogenous tendon-derived cells (TDC) and engrafted mesenchymal stem cells (MSCs) within the tendon extracellular matrix.\ud Methods: Explants from equine superficial digital flexor (extra-synovial) and deep digital flexor tendons (DDFT) from the compressed, intra-synovial and the tensile, extra-synovial regions were cultured in allogeneic or autologous SF-media. Human hamstring explants were cultured in allogeneic SF. Explant viability was assessed by staining. Proliferation of equine monolayer MSCs and TDCs in SF-media and co-culture with DDFT explants was determined by alamarblue®. Non-viable Native Tendon matrices (NNTs) were re-populated with MSCs or TDCs and cultured in SF-media. Immunohistochemical staining of tendon sections for the apoptotic proteins caspase-3, -8 and -9 was performed.\ud Results: Contact with autologous or allogeneic SF resulted in rapid death of resident tenocytes in equine and human tendon. SF did not affect the viability of equine epitenon cells, or of MSCs and TDCs in monolayer or indirect explant co-culture. MSCs and TDCs, engrafted into NNTs, died when cultured in SF. Caspase-3, -8 and -9 expression was greatest in SDFT explants exposed to allogeneic SF.\ud Conclusions: The efficacy of cells administered intra-synovially for tendon lesion repair is likely to be limited, since once incorporated into the matrix, cells become vulnerable to the adverse effects of SF. These observations could account for the poor success rate of intra-synovial tendon healing following damage to the epitenon and contact with SF, common with most soft tissue intra-synovial pathologies.
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- 2016
21. Modulation of mesenchymal stem cell genotype and phenotype by extracellular matrix proteins
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Clements, L E, Garvican, E R, Dudhia, J, and Smith, R K W
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- 2016
22. Low density lipoprotein receptor-related protein 1 (LRP1)-mediated endocytic clearance of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4): functional differences of non-catalytic domains of ADAMTS-4 and ADAMTS-5 in LRP1 binding
- Author
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Yamamoto, K, Owen, K, Parker, AE, Scilabra, SD, Dudhia, J, Strickland, DK, Troeberg, L, and Nagase, H
- Abstract
Degradation of the cartilage proteoglycan aggrecan is an early event in the development of osteoarthritis, and a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4) and ADAMTS-5 are considered to be the major aggrecan-degrading enzymes. We have recently found that ADAMTS-5 is rapidly endocytosed via low density lipoprotein receptor-related protein 1 (LRP1) and degraded by chondrocytes. Here we report that this regulatory mechanism also applies to ADAMTS-4, although its rate of endocytosis is slower than that of ADAMTS-5. Domain deletion mutagenesis of ADAMTS-4 identified that the cysteine-rich and spacer domains are responsible for binding to LRP1, whereas the thrombospondin 1 and spacer domains are responsible in ADAMTS-5. The estimated tandfrac12; value of ADAMTS-4 endocytosis was about 220 min, whereas that of ADAMTS-5 was 100 min. The difference in half-lives between the two enzymes is explained by the 13-fold lower affinity of ADAMTS-4 for LRP1 compared with that of ADAMTS-5. Studies using soluble ligand binding clusters of LRP1 showed that ADAMTS-4 binds to clusters II and IV with similar KD,app values of 98 and 73 nm, respectively, whereas ADAMTS-5 binds to cluster II, III, and IV with KD,app values of 3.5, 41, and 9 nm, respectively. Thus, ADAMTS-5 competitively inhibits ADAMTS-4 endocytosis but not vice versa. This study highlights that the affinity between a ligand and LRP1 dictates the rate of internalization and suggests that LRP1 is a major traffic controller of the two aggrecanases, especially under inflammatory conditions, where the protein levels of ADAMTS-4 increase, but those of ADAMTS-5 do not.
- Published
- 2016
23. MT1-MMP in human rheumatoid arthritis
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Miller, M-C, Manning, HB, Jain, A, Troeberg, L, Dudhia, J, Essex, D, Sandison, A, Seiki, M, Nanchahal, J, Nagase, H, and Itoh, Y
- Published
- 2016
24. Comparison of human mesenchymal stem cells expansion in basal and serum supplemented media
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Chowdhury, MWH, Carr, A, Smith, R, and Dudhia, J
- Published
- 2016
25. Expression and purification of functionally active hyaluronan-binding domains from human cartilage link protein, aggrecan and versican: formation of ternary complexes with defined hyaluronan oligosaccharides
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Seyfried, Nt, Mcvey, Gf, Almond, A., Mahoney, Dj, Dudhia, J., and Anthony Day
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carbohydrates (lipids) - Abstract
The chondroitin sulfate proteoglycan aggrecan forms link protein-stabilized complexes with hyaluronan (HA), via its N-terminal G1-domain, that provide cartilage with its load bearing properties. Similar aggregates (potentially containing new members of the link protein family), in which other chondroitin sulfate proteoglycans (i.e. versican, brevican, and neurocan) substitute for aggrecan, may contribute to the structural integrity of many other tissues including skin and brain. In this study, cartilage link protein (cLP) and the G1-domains of aggrecan (AG1) and versican (VG1) were expressed in Drosophila S2 cells. The recombinant human proteins were found to have properties similar to those described for the native molecules (e.g. cLP was able to form oligomers, and HA decasaccharides were the minimum size that could compete effectively for their binding to polymeric HA). Gel filtration and protein cross-linking/matrix-assisted laser desorption ionization time-of-flight peptide fingerprinting showed that cLP and AG1 interact in the absence or presence of HA. Conversely, cLP and VG1 did not bind directly to each other in solution yet formed ternary complexes with HA24. N-linked glycosylation of AG1 and VG1 was demonstrated to be unnecessary for either HA binding or the formation of ternary complexes. Surprisingly, the length of HA required to accommodate two G1-domains was found to be significantly larger for aggrecan than versican, which may reflect differences in the conformation of HA stabilized on binding these proteins.
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- 2016
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26. Membrane type 1 matrix metalloproteinase is a crucial promoter of synovial invasion in human rheumatoid arthritis
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Miller, M, Manning, H, Jain, A, Troeberg, L, Dudhia, J, Essex, D, Sandison, A, Seiki, M, Nanchahal, J, Nagase, H, and Itoh, Y
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musculoskeletal diseases ,Pathology ,medicine.medical_specialty ,Cartilage ,Immunology ,Arthritis ,Pannus ,Matrix metalloproteinase ,Biology ,medicine.disease ,GM6001 ,chemistry.chemical_compound ,medicine.anatomical_structure ,Rheumatology ,Synovial Cell ,chemistry ,Cancer research ,medicine ,Immunology and Allergy ,Pharmacology (medical) ,Synovial membrane ,Aggrecan - Abstract
Objective A hallmark of rheumatoid arthritis (RA) is invasion of the synovial pannus into cartilage, and this process requires degradation of the collagen matrix. The aim of this study was to explore the role of one of the collagen-degrading matrix metalloproteinases (MMPs), membrane type 1 MMP (MT1-MMP), in synovial pannus invasiveness. Methods The expression and localization of MT1-MMP in human RA pannus were investigated by Western blot analysis of primary synovial cells and immunohistochemical analysis of RA joint specimens. The functional role of MT1-MMP was analyzed by 3-dimensional (3-D) collagen invasion assays and a cartilage invasion assay in the presence or absence of tissue inhibitor of metalloproteinases 1 (TIMP-1), TIMP-2, or GM6001. The effect of adenoviral expression of a dominant-negative MT1-MMP construct lacking a catalytic domain was also examined. Results MT1-MMP was highly expressed at the pannus–cartilage junction in RA joints. Freshly isolated rheumatoid synovial tissue and isolated RA synovial fibroblasts invaded into a 3-D collagen matrix in an MT1-MMP–dependent manner. Invasion was blocked by TIMP-2 and GM6001 but not by TIMP-1. Invasion was also inhibited by the overexpression of a dominant-negative MT1-MMP, which inhibits collagenolytic activity and proMMP-2 activation by MT1-MMP on the cell surface. Synovial fibroblasts also invaded into cartilage in an MT1-MMP–dependent manner. This process was further enhanced by removing aggrecan from the cartilage matrix. Conclusion MT1-MMP serves as an essential collagen-degrading proteinase during pannus invasion in human RA. Specific inhibition of MT1-MMP–dependent invasion may represent a novel therapeutic strategy for RA.
- Published
- 2016
27. Revised cloud processes to improve the mean and intraseasonal variability of I ndian summer monsoon in climate forecast system: Part 1
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Abhik, S., primary, Krishna, R. P. M., additional, Mahakur, M., additional, Ganai, Malay, additional, Mukhopadhyay, P., additional, and Dudhia, J., additional
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- 2017
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28. Investigating the Postmortem Molecular Biology of Cartilage and its Potential Forensic Applications
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Bolton, S N, Whitehead, M P, Dudhia, J, Baldwin, T C, and Sutton, R
- Abstract
This study investigated the postmortem molecular changes that articular cartilage undergoes following burial. Fresh pig trotters were interred in 30‐cm‐deep graves at two distinct locations exhibiting dissimilar soil environments for up to 42 days. Extracts of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joint cartilage from trotters disinterred weekly over 6 weeks were analyzed by Western blot against the monoclonal antibody 2‐B‐6 to assess aggrecan degradation. In both soil conditions, aggrecan degradation by‐products of decreasing molecular size and complexity were observed up to 21 days postmortem. Degradation products were undetected after this time and coincided with MCP/MTP joint exposure to the soil environment. These results show that cartilage proteoglycans undergo an ordered molecular breakdown, the analysis of which may have forensic applications. This model may prove useful for use as a human model and for forensic investigations concerning crimes against animals and the mortality of endangered species.
- Published
- 2015
29. Influence of commonly used pharmaceutical agents on equine bone marrow-derived mesenchymal stem cell viability
- Author
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Edmonds, R. E., primary, Garvican, E. R., additional, Smith, R. K. W., additional, and Dudhia, J., additional
- Published
- 2016
- Full Text
- View/download PDF
30. Expression of Sulf1 and Sulf2 in cartilage, bone and endochondral fracture healing
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Zaman, G., primary, Staines, K. A., additional, Farquharson, C., additional, Newton, P. T., additional, Dudhia, J., additional, Chenu, C., additional, Pitsillides, A. A., additional, and Dhoot, G. K., additional
- Published
- 2015
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31. Revised cloud processes to improve the mean and intraseasonal variability of Indian summer monsoon in climate forecast system: Part 1.
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Abhik, S., Krishna, R. P. M., Mahakur, M., Ganai, Malay, Mukhopadhyay, P., and Dudhia, J.
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MONSOONS ,PRECIPITATION (Chemistry) ,PARAMETERIZATION ,HYDROMETEOROLOGY ,CLOUDS - Abstract
The National Centre for Environmental Prediction (NCEP) Climate Forecast System (CFS) is being used for operational monsoon prediction over the Indian region. Recent studies indicate that the moist convective process in CFS is one of the major sources of uncertainty in monsoon predictions. In this study, the existing simple cloud microphysics of CFS is replaced by the six-class Weather Research Forecasting (WRF) single moment (WSM6) microphysical scheme. Additionally, a revised convective parameterization is employed to improve the performance of the model in simulating the boreal summer mean climate and intraseasonal variability over the Indian summer monsoon (ISM) region. The revised version of the model (CFSCR) exhibits a potential to improve shortcomings in the seasonal mean precipitation distribution relative to the standard CFS (CTRL), especially over the ISM region. Consistently, notable improvements are also evident in other observed ISM characteristics. These improvements are found to be associated with a better simulation of spatial and vertical distributions of cloud hydrometeors in CFSCR. A reasonable representation of the subgrid-scale convective parameterization along with cloud hydrometeors helps to improve the convective and large-scale precipitation distribution in the model. As a consequence, the simulated low-frequency boreal summer intraseasonal oscillation (BSISO) exhibits realistic propagation and the observed northwest-southeast rainband is well reproduced in CFSCR. Additionally, both the high and low-frequency BSISOs are better captured in CFSCR. The improvement of low and high-frequency BSISOs in CFSCR is shown to be related to a realistic phase relationship of clouds. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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32. Influence of commonly used pharmaceutical agents on equine bone marrow-derived mesenchymal stem cell viability.
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Edmonds, R. E., Garvican, E. R., Smith, R. K. W., and Dudhia, J.
- Abstract
Reason for performing study To provide evidence to support recommendations regarding the co-administration of drugs with mesenchymal stem cell ( MSC) therapy. Objectives To determine the influence of sedatives, local anaesthetic and corticosteroids on MSC viability and proliferation, in comparison to somatic cells derived from tendon ( TDCs). Study design In vitro cell culture. Materials and methods MSCs (n = 3) and TDCs (n = 2) were cultured in media containing a clinically relevant dose range of xylazine, romifidine, detomidine and butorphanol, mepivacaine, methylprednisolone, or triamcinolone acetonide. Cell viability in suspension culture was assessed at intervals up to 4 h using the trypan blue dye assay. MSCs in monolayer culture were exposed to the highest concentrations of drug and proliferation was measured using the alamarBlue fluorescence assay. Results Exposure to romifidine or mepivacaine did not significantly affect viability or proliferation rate of MSCs or TDCs at any of the dosages tested. At the highest concentration of detomidine and butorphanol, MSC viability was significantly reduced compared to controls. Although xylazine exposure caused a significant (P < 0.001), dose-dependent reduction in MSC viability compared to controls, overall population viability remained good. Conversely, both methylprednisolone and triamcinolone resulted in the rapid death of significant numbers of MSCs (P < 0.001). Conclusions Clinicians can sedate horses and administer nerve blocks to assist in intratendinous or intrathecal injection of MSCs with confidence that these drugs will not impact the viability of implanted cells. However, the concomitant use of corticosteroids is likely to have a severely detrimental effect on cell viability and should not be performed. Similarly, steroid administration into the sheath of a damaged tendon is not recommended. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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33. Circulating concentrations of a marker of type I collagen metabolism are associated with hypertrophic cardiomyopathy mutation status in ragdoll cats
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Borgeat, K., primary, Dudhia, J., additional, Luis Fuentes, V., additional, and Connolly, D. J., additional
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- 2015
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34. The use of a numerical weather prediction model to simulate the release of a dense gas with an application to the Lake Nyos disaster of 1986.
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Burton, R. R., Dudhia, J., Gadian, A. M., and Mobbs, S. D.
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- *
WEATHER forecasting , *ASTROMETEOROLOGY , *GEOPHYSICAL prediction , *GRAVITY , *PREDICTION models - Abstract
ABSTRACT The spread of a dense gas in the atmosphere is a phenomenon that occurs widely with natural (and anthropogenic) causes and is often associated with high impact and hazardous events. In this study a method of simulating the spread of dense gases in a numerical weather prediction model is presented. This approach has the advantage that dense gases can be simulated in regions of complex terrain using realistic forcings (in terms of both the driving meteorological fields and the representation of surface characteristics). The model formulation is tested against semi-idealized gravity-current-type experiments and similar modelling studies. As an example application, the Lake Nyos disaster of 1986, where a dense CO2 cloud spread through a mountainous region of Cameroon, is simulated. The predicted spread of CO2 agrees (qualitatively) very well with the observations. The method provides a means of determining a potential 'safe height' above which simulated concentrations are not hazardous, and thus the height above which refuge should be taken during similar future events. The simulation demonstrates a novel application which can be rapidly applied to other scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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35. Irrigation impact on precipitation during a heatwave event using WRF-ARW: The summer 2015 Po Valley case
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Francesco Pilla, Jimy Dudhia, Arianna Valmassoi, Silvana Di Sabatino, and Valmassoi A., Dudhia J., Di Sabatino S., Pilla, Francesco
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Atmospheric Science ,Irrigation ,010504 meteorology & atmospheric sciences ,Moisture ,Precipitation ,010501 environmental sciences ,Atmospheric sciences ,01 natural sciences ,Convective available potential energy ,Weather Research and Forecasting Model ,Environmental science ,Atmospheric modelling ,Level of free convection ,Lifted condensation level ,Air mass ,0105 earth and related environmental sciences - Abstract
Irrigation is crucial in sustaining food production and it is found to have a cooling effect. Changes at the surface affect both the circulation and the precipitation. The magnitude depends on the model used, the irrigation description and the water amount, as well as the region. The study focuses on northern Italy (the Po Valley) due to its vulnerability to heatwaves and dependency on local water sources. This study is performed with the Weather Research and Forecasting (WRF) model and newly developed irrigation parameterizations defined by different evaporative processes. The model runs at a 3 km convection-permitting resolution, starting in May 2015 and analyzing July. An irrigation amount of 5.7 mm is applied daily at 5 UTC for 3 h, starting from May 15. A set of convection-parameterized sensitivity simulations is used to investigate the results' dependency on timing. Using a convection-parameterized set of experiments, it is assessed that irrigation increases the precipitation accumulated over the region. While irrigation modifies the air mass properties, convection-permitting runs show that afternoon events are inhibited due to an increase in convection inhibition and decrease in boundary layer height. This happens despite the increase in the convective available potential energy (CAPE) and a decrease in both the lifting condensation level and level of free convection. For the nighttime event, irrigation increases significantly both boundary layer moisture and CAPE, increasing the precipitation. All cases are compared against the national radar composite accumulated over two hours, finding that the irrigated runs perform better than the control.
- Published
- 2020
36. CRISPR/Cas9 gene editing in induced pluripotent stem cells to investigate the feline hypertrophic cardiomyopathy causing MYBPC3/R820W mutation.
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Dutton LC, Dudhia J, Guest DJ, and Connolly DJ
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- Animals, Cats, Humans, Cell Differentiation, Cat Diseases genetics, Cat Diseases pathology, Induced Pluripotent Stem Cells metabolism, Cardiomyopathy, Hypertrophic genetics, Cardiomyopathy, Hypertrophic pathology, Cardiomyopathy, Hypertrophic veterinary, CRISPR-Cas Systems, Gene Editing, Carrier Proteins genetics, Myocytes, Cardiac metabolism, Myocytes, Cardiac pathology, Mutation
- Abstract
Hypertrophic cardiomyopathy (HCM) is the most common heart disease in domestic cats, often leading to congestive heart failure and death, with current treatment strategies unable to reverse or prevent progression of the disease. The underlying pathological processes driving HCM remain unclear, which hinders novel drug discovery. The aim of this study was to generate a cellular model of the feline HCM-causing MYBPC3 mutation R820W. Using CRISPR/Cas9 gene editing we introduced the R820W mutation into a human induced pluripotent stem cell (iPSC) line. We differentiated both homozygous mutant clones and isogenic control clones to cardiomyocytes (iPSC-CMs). Protein quantification indicated that haploinsufficiency is not the disease mechanism of the mutation. Homozygous mutant iPSC-CMs had a larger cell area than isogenic controls, with the sarcomere structure and incorporation of cMyBP-C appearing similar between mutant and control iPSC-CMs. Contraction kinetic analysis indicated that homozygous iPSC-CMs have impaired relaxation and are hypocontractile compared to isogenic control iPSC-CMs. In summary, we demonstrate successful generation of an iPSC model of a feline MYBPC3 mutation, with the cellular model recapitulating aspects of HCM including cellular hypertrophy and impaired relaxation kinetics. We anticipate that further study of this model will lead to improved understanding of the disease-causing molecular mechanism, ultimately leading to novel drug discovery., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Dutton et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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37. A SIRT1-independent mechanism mediates protection against steroid-induced senescence by resveralogues in equine tenocytes.
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Heidari N, Faragher RGA, Pattison G, Dudhia J, and Smith RKW
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- Animals, Horses, Resveratrol pharmacology, Cell Proliferation drug effects, Tumor Suppressor Protein p53 metabolism, Tendinopathy metabolism, Tendinopathy pathology, Tendinopathy drug therapy, Cells, Cultured, Tendons drug effects, Tendons cytology, Tendons metabolism, Sirtuin 1 metabolism, Cellular Senescence drug effects, Tenocytes drug effects, Tenocytes metabolism, Dexamethasone pharmacology
- Abstract
Tendinopathy is a common age-related disease which causes significant morbidity for both human athletes and performance horses. In the latter, the superficial digital flexor tendon is an excellent model for human tendinopathies because it is a functional homologue of the human Achilles tendon and a primary site of injuries with strong similarities to the human disease. Corticosteroids have been previously used clinically to treat tendinopathic inflammation, but they upregulate the p53-p21 axis with concomitant reductions in cell proliferation and collagen synthesis in human tenocytes. This phenotype is consistent with the induction of cellular senescence in vitro and in vivo and probably represents an important clinical barrier to their effective use. Because of the many differences in senescence mechanisms between species, this study aimed to evaluate these mechanisms after corticosteroid treatment in equine tenocytes. Exposure to clinically reflective levels of dexamethasone for 48 hours drove equine tenocytes into steroid induced senescence (SIS). This was characterised by permanent growth arrest and upregulation of p53, the cyclin dependent kinase inhibitors p21waf and p16ink4a as well as the matrix degrading enzymes MMP1, MMP2 and MMP13. SIS also induced a distinctive equine senescence associated secretory phenotype (eSASP) characterised by enhanced secretion of IL-8 and MCP-1. Preincubation with resveratrol or the potent SIRT1 activator SRT1720 prevented SIS in equine tenocytes, while treatment with the non-SIRT1 activating resveratrol analogue V29 was equally protective against SIS, consistent with a novel, as yet uncharacterised SIRT1-indendent mechanism which has relevance for the development of future preventative and therapeutic strategies., Competing Interests: NO authors have competing interests., (Copyright: © 2024 Heidari et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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38. Equine Embryonic Stem Cell-Derived Tenocytes are Insensitive to a Combination of Inflammatory Cytokines and Have Distinct Molecular Responses Compared to Primary Tenocytes.
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Smith EJ, Beaumont RE, Dudhia J, and Guest DJ
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- Animals, Horses, Signal Transduction drug effects, Inflammation pathology, Inflammation metabolism, Cells, Cultured, Tendons cytology, Tenocytes cytology, Tenocytes metabolism, Tenocytes drug effects, Cytokines metabolism, NF-kappa B metabolism, Embryonic Stem Cells cytology, Embryonic Stem Cells metabolism, Embryonic Stem Cells drug effects
- Abstract
Tissue fibrosis following tendon injury is a major clinical problem due to the increased risk of re-injury and limited treatment options; however, its mechanism remains unclear. Evidence suggests that insufficient resolution of inflammation contributes to fibrotic healing by disrupting tenocyte activity, with the NF-κB pathway being identified as a potential mediator. Equine embryonic stem cell (ESC) derived tenocytes may offer a potential cell-based therapy to improve tendon regeneration, but how they respond to an inflammatory environment is largely unknown. Our findings reveal for the first time that, unlike adult tenocytes, ESC-tenocytes are unaffected by IFN-γ, TNFα, and IL-1β stimulation; producing minimal changes to tendon-associated gene expression and generating 3-D collagen gel constructs indistinguishable from unstimulated controls. Inflammatory pathway analysis found these inflammatory cytokines failed to activate NF-κB in the ESC-tenocytes. However, NF-κB could be activated to induce changes in gene expression following stimulation with NF-κB pharmaceutical activators. Transcriptomic analysis revealed differences between cytokine and NF-κB signalling components between adult and ESC-tenocytes, which may contribute to the mechanism by which ESC-tenocytes escape inflammatory stimuli. Further investigation of these molecular mechanisms will help guide novel therapies to reduce fibrosis and encourage superior tendon healing., (© 2024. The Author(s).)
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- 2024
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39. Technical note: Cartilage imaging with sub-cellular resolution using a laboratory-based phase-contrast x-ray microscope.
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Esposito M, Astolfo A, Cipiccia S, Jones CM, Savvidis S, Ferrara JD, Endrizzi M, Dudhia J, and Olivo A
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- Animals, Horses, X-Rays, Radiography, Laboratories, Cartilage diagnostic imaging, Microscopy
- Abstract
Background: Microscopic imaging of cartilage is a key tool for the study and development of treatments for osteoarthritis. When cellular and sub-cellular resolution is required, histology remains the gold standard approach, albeit limited by the lack of volumetric information as well as by processing artifacts. Cartilage imaging with the sub-cellular resolution has only been demonstrated in the synchrotron environment., Purpose: To provide a proof-of-concept demonstration of the capability of a laboratory-based x-ray phase-contrast microscope to resolve sub-cellular features in a cartilage sample., Methods: This work is based on a laboratory-based x-ray microscope using intensity-modulation masks. The structured nature of the beam, resulting from the mask apertures, allows the retrieval of three contrast channels, namely, transmission, refraction and dark-field, with resolution depending only on the mask aperture width. An ex vivo equine cartilage sample was imaged with the x-ray microscope and results were validated with synchrotron tomography and histology., Results: Individual chondrocytes, that is, cells responsible for cartilage formation, could be detected with the laboratory-based microscope. The complementarity of the three retrieved contrast channels allowed the detection of sub-cellular features in the chondrocytes., Conclusions: We provide the first proof-of-concept of imaging cartilage tissue with sub-cellular resolution using a laboratory-based x-ray microscope., (© 2023 The Authors. Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)
- Published
- 2023
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40. Effects of resveratrol and its analogues on the cell cycle of equine mesenchymal stem/stromal cells.
- Author
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Tamura N, Heidari N, Faragher RGA, Smith RKW, and Dudhia J
- Abstract
Resveratrol (RSV; trans-3,5,4'-trihydroxystilbene) strongly activates sirtuin 1, and it and its analogue V29 enhance the proliferation of mesenchymal stem/stromal cells (MSCs).Although culture medium containing 5-azacytydine and RSV inhibits senescence of adipose tissue-derived MSCs isolated from horses with metabolic syndrome, few studies have reported the effects of RSV on equine bone marrow-derived MSCs (eBMMSCs) isolated from horses without metabolic syndrome. The aim of this study was to investigate the effects of RSV and V29 on the cell cycle of eBMMSCs. Following treatment with 5 µM RSV or 10 µM V29, the cell proliferation capacity of eBMMSCs derived from seven horses was evaluated by EdU (5-ethynyl-2'-deoxyuridine) and Ki-67 antibody assays. Brightfield images of cells and immunofluorescent images of EdU, Ki-67, and DAPI staining were recorded by fluorescence microscopy, and the number of cells positive for each was quantified and compared by Friedman's test at P<0.05. The growth fraction of eBMMSCs was significantly increased by RSV and V29 as measured by the EdU assay (control 28.1% ± 13.8%, V29 31.8% ± 14.6%, RSV 32.0% ± 10.8%; mean ± SD; P<0.05) but not as measured by the Ki-67 antibody assay (control 27.0% ± 11.2%, V29 27.4% ± 10.8%, RSV 27.7% ± 6.8%). RSV and V29 promoted progression of the cell cycle of eBMMSCs into the S phase and may be useful for eBMMSC expansion., (©2023 The Japanese Society of Equine Science.)
- Published
- 2023
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41. Exploration of Mediators Associated with Myocardial Remodelling in Feline Hypertrophic Cardiomyopathy.
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Cheng WC, Lawson C, Liu HH, Wilkie L, Dobromylskyj M, Luis Fuentes V, Dudhia J, and Connolly DJ
- Abstract
Hypertrophic cardiomyopathy (HCM) affects both humans and cats and exhibits considerable interspecies similarities that are exemplified by underlying pathological processes and clinical presentation to the extent that developments in the human field may have direct relevance to the feline disease. Characteristic changes on histological examination include cardiomyocyte hypertrophy and interstitial and replacement fibrosis. Clinically, HCM is characterised by significant diastolic dysfunction due to a reduction in ventricular compliance and relaxation associated with extracellular matrix (ECM) remodelling and the development of ventricular hypertrophy. Studies in rodent models and human HCM patients have identified key protein mediators implicated in these pathological changes, including lumican, lysyl oxidase and TGF-β isoforms. We therefore sought to quantify and describe the cellular location of these mediators in the left ventricular myocardium of cats with HCM and investigate their relationship with the quantity and structural composition of the ECM. We identified increased myocardial content of lumican, LOX and TGF-β2 mainly attributed to their increased expression within cardiomyocytes in HCM cats compared to control cats. Furthermore, we found strong correlations between the expressions of these mediators that is compatible with their role as important components of cellular pathways promoting remodelling of the left ventricular myocardium. Fibrosis and hypertrophy are important pathological changes in feline HCM, and a greater understanding of the mechanisms driving this pathology may facilitate the identification of potential therapies.
- Published
- 2023
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42. Influence of Rho/ROCK inhibitor Y-27632 on proliferation of equine mesenchymal stromal cells.
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Melzer M, Burk J, Guest DJ, and Dudhia J
- Abstract
Mesenchymal stromal cells (MSC) isolated form bone marrow and adipose tissue are the most common cells used for cell therapy of orthopedic diseases. MSC derived from different tissues show differences in terms of their proliferation, differentiation potential and viability in prolonged cell culture. This suggests that there may be subtle differences in intracellular signaling pathways that modulate these cellular characteristics. The Rho/ROCK signaling pathway is essential for many cellular functions. Targeting of this pathway by the ROCK inhibitor Y-27632 has been shown to be beneficial for cell viability and proliferation of different cell types. The aim of this study was to investigate the effects of Rho/ROCK inhibition on equine MSC proliferation using bone marrow-derived MSC (BMSC) and adipose-derived MSC (ASC). Primary ASC and BMSC were stimulated with or without 10 ng/mL TGF-β3 or 10 μM Y-27632, as well as both in combination. Etoposide at 10 μM was used as a positive control for inhibition of cell proliferation. After 48 h of stimulation, cell morphology, proliferation activity and gene expression of cell senescence markers p53 and p21 were assessed. ASC showed a trend for higher basal proliferation than BMSC, which was sustained following stimulation with TGF-β3. This included a higher proliferation with TGF-β3 stimulation compared to Y-27632 stimulation ( p < 0.01), but not significantly different to the no treatment control when used in combination. Expression of p21 and p53 was not altered by stimulation with TGF-β3 and/or Y-27632 in either cell type. In summary, the Rho/ROCK inhibitor Y-27632 had no effect on proliferation activity and did not induce cell senescence in equine ASC and BMSC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Melzer, Burk, Guest and Dudhia.)
- Published
- 2023
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43. Transdermal drug delivery in horses: An in vitro comparison of skin structure and permeation of two model drugs at various anatomical sites.
- Author
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Bizley SC, Dudhia J, Smith RKW, and Williams AC
- Abstract
Background: Oral and parenteral drug delivery in horses can be difficult. Equine-specific transdermal drug formulations offer improved ease of treatment; development of such formulations requires a deeper understanding of the structural and chemical tissue barrier of horse skin., Hypothesis/objectives: To compare the structural composition and barrier properties of equine skin., Animals: Six warmblood horses (two males, four females) with no skin diseases., Materials and Methods: Routine histological and microscopic analyses were carried out with image analysis for skin from six different anatomical locations. In vitro drug permeation was analysed using a standard Franz diffusion cell protocol coupled with reversed phase-high-performance liquid chromatography detailing flux, lag times and tissue partitioning ratios of two model drug compounds., Results: Epidermal and dermal thicknesses varied between sites. The dermal and epidermal thicknesses of the croup were 1764 ± 115 μm and 36 ± 3.6 μm, respectively, and were significantly different (p < 0.05) from the inner thigh thicknesses which were 824 ± 35 μm and 49 ± 3.6 μm. Follicular density and size also varied. The highest flux for the model hydrophilic molecule (caffeine) was for the flank (3.22 ± 0.36 μg/cm
2 /h), while that for the lipophilic molecule (ibuprofen) was for the inner thigh (0.12 ± 0.02 μg/cm2 /h)., Conclusions and Clinical Relevance: Anatomical location differences in equine skin structure and small molecule permeability were demonstrated. These results can aid in the development of transdermal therapies for horses., (© 2023 The Authors. Veterinary Dermatology published by John Wiley & Sons Ltd on behalf of ESVD and ACVD.)- Published
- 2023
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44. Tumour necrosis factor alpha, interleukin 1 beta and interferon gamma have detrimental effects on equine tenocytes that cannot be rescued by IL-1RA or mesenchymal stromal cell-derived factors.
- Author
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Smith EJ, Beaumont RE, McClellan A, Sze C, Palomino Lago E, Hazelgrove L, Dudhia J, Smith RKW, and Guest DJ
- Subjects
- Humans, Animals, Horses, Tumor Necrosis Factor-alpha metabolism, Interleukin-1beta metabolism, NF-kappa B metabolism, Interleukin 1 Receptor Antagonist Protein genetics, Interleukin 1 Receptor Antagonist Protein metabolism, Interferon-gamma metabolism, Tenocytes metabolism, Cells, Cultured, Mesenchymal Stem Cells, Tendinopathy metabolism
- Abstract
Tendon injuries occur commonly in both human and equine athletes, and poor tendon regeneration leads to functionally deficient scar tissue and an increased frequency of re-injury. Despite evidence suggesting inadequate resolution of inflammation leads to fibrotic healing, our understanding of the inflammatory pathways implicated in tendinopathy remains poorly understood, meaning successful targeted treatments are lacking. Here, we demonstrate IL-1β, TNFα and IFN-γ work synergistically to induce greater detrimental consequences for equine tenocytes than when used individually. This includes altering tendon associated and matrix metalloproteinase gene expression and impairing the cells' ability to contract a 3-D collagen gel, a culture technique which more closely resembles the in vivo environment. Moreover, these adverse effects cannot be rescued by direct suppression of IL-1β using IL-1RA or factors produced by BM-MSCs. Furthermore, we provide evidence that NF-κB, but not JNK, P38 MAPK or STAT 1, is translocated to the nucleus and able to bind to DNA in tenocytes following TNFα and IL-1β stimulation, suggesting this signalling cascade may be responsible for the adverse downstream consequences of these inflammatory cytokines. We suggest a superior approach for treatment of tendinopathy may therefore be to target specific signalling pathways such as NF-κB., (© 2022. The Author(s).)
- Published
- 2023
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45. The tendon interfascicular basement membrane provides a vascular niche for CD146+ cell subpopulations.
- Author
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Marr N, Zamboulis DE, Werling D, Felder AA, Dudhia J, Pitsillides AA, and Thorpe CT
- Abstract
Introduction: The interfascicular matrix (IFM; also known as the endotenon) is critical to the mechanical adaptations and response to load in energy-storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT). We hypothesized that the IFM is a tendon progenitor cell niche housing an exclusive cell subpopulation. Methods: Immunolabelling of equine superficial digital flexor tendon was used to identify the interfascicular matrix niche, localising expression patterns of CD31 (endothelial cells), Desmin (smooth muscle cells and pericytes), CD146 (interfascicular matrix cells) and LAMA4 (interfascicular matrix basement membrane marker). Magnetic-activated cell sorting was employed to isolate and compare in vitro properties of CD146+ and CD146- subpopulations. Results: Labelling for CD146 using standard histological and 3D imaging of large intact 3D segments revealed an exclusive interfascicular cell subpopulation that resides in proximity to a basal lamina which forms extensive, interconnected vascular networks. Isolated CD146+ cells exhibited limited mineralisation (osteogenesis) and lipid production (adipogenesis). Discussion: This study demonstrates that the interfascicular matrix is a unique tendon cell niche, containing a vascular-rich network of basement membrane, CD31+ endothelial cells, Desmin+ mural cells, and CD146+ cell populations that are likely essential to tendon structure and/or function. Contrary to our hypothesis, interfascicular CD146+ subpopulations did not exhibit stem cell-like phenotypes. Instead, our results indicate CD146 as a pan-vascular marker within the tendon interfascicular matrix. Together with previous work demonstrating that endogenous tendon CD146+ cells migrate to sites of injury, our data suggest that their mobilisation to promote intrinsic repair involves changes in their relationships with local interfascicular matrix vascular and basement membrane constituents., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Marr, Zamboulis, Werling, Felder, Dudhia, Pitsillides and Thorpe.)
- Published
- 2023
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46. Potential effects of Land Use Land Cover Change on streamflow over the Sokoto Rima River Basin.
- Author
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Achugbu IC, Olufayo AA, Balogun IA, Dudhia J, McAllister M, Adefisan EA, and Naabil E
- Abstract
This research investigated the effects of Land Use Land Cover Change (LULCC) over the Sokoto Rima River Basin (SRRB) using a setup of Weather Research and Forecasting (WRF) atmospheric model to generate the parameters to force WRF hydrological (WRF-Hydro) model which comprises of a parent domain at 12km horizontal resolution with an updated MODIS Land Use (LU) data and the nested domain at 4km resolution which focuses on the SRRB. The calibration of the model was done by modifying the infiltration and the Manning's roughness parameters. WRF-Hydro model was used to run simulations with the control LU and five different LU scenarios generated for Urban (Ur), Grassland (Gr), Savanna (Sa), Forest (Fr) and Barren (Ba). For the period analysed, simulation with Gr scenario increased streamflow in all the forecast points, while the Sa decreases it. A strong correlation was noted between the input precipitation and streamflow for all LU scenarios, and a significant Specific Discharge to Rainfall (SDR) for Ur, Fr and Ba scenarios. There was an increase in streamflow in the dry period due to afforestation and a decrease due to deforestation. Areas where grasslands were converted into savanna showed a little increase in evapotranspiration ET. There was more ET for the Sa scenario than the Gr scenario in the wet period, while there was more ET in the dry period for Gr scenario than it is for the Sa scenario. The study has shown that ET is a major factor to changes in streamflow due to LU changes over the basin. The sensitivity of the model to LULCC is reasonable, but more research is recommended to compare results with different hydrological model popularly used for LULCC impact studies., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)
- Published
- 2022
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47. Position Statement: Minimal Criteria for Reporting Veterinary and Animal Medicine Research for Mesenchymal Stromal/Stem Cells in Orthopedic Applications.
- Author
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Guest DJ, Dudhia J, Smith RKW, Roberts SJ, Conzemius M, Innes JF, Fortier LA, and Meeson RL
- Abstract
Competing Interests: JI is employed by CVS Group plc. With the University of Liverpool, JI is the joint license holder for the LOAD client-reported outcomes measure. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Published
- 2022
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48. CD146 Delineates an Interfascicular Cell Sub-Population in Tendon That Is Recruited during Injury through Its Ligand Laminin-α4.
- Author
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Marr N, Meeson R, Kelly EF, Fang Y, Peffers MJ, Pitsillides AA, Dudhia J, and Thorpe CT
- Subjects
- Achilles Tendon metabolism, Achilles Tendon pathology, Animals, CD146 Antigen genetics, Disease Models, Animal, Disease Susceptibility, Female, Fluorescent Antibody Technique, Gene Expression, Ligands, Protein Binding, Rats, Tendon Injuries etiology, Tendon Injuries pathology, Tendons pathology, CD146 Antigen metabolism, Extracellular Matrix metabolism, Laminin metabolism, Tendon Injuries metabolism, Tendons metabolism
- Abstract
The interfascicular matrix (IFM) binds tendon fascicles and contains a population of morphologically distinct cells. However, the role of IFM-localised cell populations in tendon repair remains to be determined. The basement membrane protein laminin-α4 also localises to the IFM. Laminin-α4 is a ligand for several cell surface receptors, including CD146, a marker of pericyte and progenitor cells. We used a needle injury model in the rat Achilles tendon to test the hypothesis that the IFM is a niche for CD146+ cells that are mobilised in response to tendon damage. We also aimed to establish how expression patterns of circulating non-coding RNAs alter with tendon injury and identify potential RNA-based markers of tendon disease. The results demonstrate the formation of a focal lesion at the injury site, which increased in size and cellularity for up to 21 days post injury. In healthy tendon, CD146+ cells localised to the IFM, compared with injury, where CD146+ cells migrated towards the lesion at days 4 and 7, and populated the lesion 21 days post injury. This was accompanied by increased laminin-α4, suggesting that laminin-α4 facilitates CD146+ cell recruitment at injury sites. We also identified a panel of circulating microRNAs that are dysregulated with tendon injury. We propose that the IFM cell niche mediates the intrinsic response to injury, whereby an injury stimulus induces CD146+ cell migration. Further work is required to fully characterise CD146+ subpopulations within the IFM and establish their precise roles during tendon healing.
- Published
- 2021
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49. Large Animal Models in Regenerative Medicine and Tissue Engineering: To Do or Not to Do.
- Author
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Ribitsch I, Baptista PM, Lange-Consiglio A, Melotti L, Patruno M, Jenner F, Schnabl-Feichter E, Dutton LC, Connolly DJ, van Steenbeek FG, Dudhia J, and Penning LC
- Abstract
Rapid developments in Regenerative Medicine and Tissue Engineering has witnessed an increasing drive toward clinical translation of breakthrough technologies. However, the progression of promising preclinical data to achieve successful clinical market authorisation remains a bottleneck. One hurdle for progress to the clinic is the transition from small animal research to advanced preclinical studies in large animals to test safety and efficacy of products. Notwithstanding this, to draw meaningful and reliable conclusions from animal experiments it is critical that the species and disease model of choice is relevant to answer the research question as well as the clinical problem. Selecting the most appropriate animal model requires in-depth knowledge of specific species and breeds to ascertain the adequacy of the model and outcome measures that closely mirror the clinical situation. Traditional reductionist approaches in animal experiments, which often do not sufficiently reflect the studied disease, are still the norm and can result in a disconnect in outcomes observed between animal studies and clinical trials. To address these concerns a reconsideration in approach will be required. This should include a stepwise approach using in vitro and ex vivo experiments as well as in silico modeling to minimize the need for in vivo studies for screening and early development studies, followed by large animal models which more closely resemble human disease. Naturally occurring, or spontaneous diseases in large animals remain a largely untapped resource, and given the similarities in pathophysiology to humans they not only allow for studying new treatment strategies but also disease etiology and prevention. Naturally occurring disease models, particularly for longer lived large animal species, allow for studying disorders at an age when the disease is most prevalent. As these diseases are usually also a concern in the chosen veterinary species they would be beneficiaries of newly developed therapies. Improved awareness of the progress in animal models is mutually beneficial for animals, researchers, human and veterinary patients. In this overview we describe advantages and disadvantages of various animal models including domesticated and companion animals used in regenerative medicine and tissue engineering to provide an informed choice of disease-relevant animal models., (Copyright © 2020 Ribitsch, Baptista, Lange-Consiglio, Melotti, Patruno, Jenner, Schnabl-Feichter, Dutton, Connolly, van Steenbeek, Dudhia and Penning.)
- Published
- 2020
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50. Histological evaluation of cellular response to a multifilament electrospun suture for tendon repair.
- Author
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Rashid M, Dudhia J, Dakin SG, Snelling S, Lach A, De Godoy R, Mouthuy PA, Smith R, Morrey M, and Carr AJ
- Subjects
- Animals, Disease Models, Animal, Female, Humans, Postoperative Complications etiology, Rotator Cuff pathology, Rotator Cuff surgery, Rotator Cuff Injuries pathology, Sheep, Suture Techniques adverse effects, Tensile Strength, Polydioxanone adverse effects, Postoperative Complications pathology, Rotator Cuff Injuries surgery, Suture Techniques instrumentation, Sutures adverse effects
- Abstract
Background: Rotator cuff tendon repair in humans is a commonly performed procedure aimed at restoring the tendon-bone interface. Despite significant innovation of surgical techniques and suture anchor implants, only 60% of repairs heal successfully. One strategy to enhance repair is the use of bioactive sutures that provide the native tendon with biophysical cues for healing. We investigated the tissue response to a multifilament electrospun polydioxanone (PDO) suture in a sheep tendon injury model characterised by a natural history of failure of healing., Methodology and Results: Eight skeletally mature English Mule sheep underwent repair with electrospun sutures. Monofilament sutures were used as a control. Three months after surgery, all tendon repairs healed, without systemic features of inflammation, signs of tumour or infection at necropsy. A mild local inflammatory reaction was seen. On histology the electrospun sutures were densely infiltrated with predominantly tendon fibroblast-like cells. In comparison, no cellular infiltration was observed in the control suture. Neovascularisation was observed within the electrospun suture, whilst none was seen in the control. Foreign body giant cells were rarely seen with either sutures., Conclusion: This study demonstrates that a tissue response can be induced in tendon with a multifilament electrospun suture with no safety concerns., Competing Interests: I declare that I am the inventor on a patent application related to the technology underlying the manufacturing of the ES suture (WO2015040399, Electrospun filaments, filed in September 2013). This does not alter our adherence to PLOS ONE policies on sharing data and materials. I also confirm on behalf of all authors that there is no other competing interests.
- Published
- 2020
- Full Text
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