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Retaining dermatology patients in primary care through dialogue with secondary care providers: A service evaluation. Ann Dermatol Venereol 2024; 151:103248. [PMID: 38513422 DOI: 10.1016/j.annder.2024.103248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/28/2023] [Accepted: 11/07/2023] [Indexed: 03/23/2024]
Abstract
BACKGROUND There are long patient waiting lists for specialist care. A dermatology dialogue service between primary and secondary care (DDPS) was developed in eastern England. Primary care referrers uploaded patient images of skin conditions for review by and dialogue with consultant dermatologists in an attempt to retain patients in primary care rather than refer them to secondary care. METHODS Evaluation of service performance against specific targets, including reduction in secondary care waiting list growth over the period April 2021-March 2022 inclusive. Service activity was summarized in terms of speed of resolution, case numbers, and dispositions. Clinician and patient satisfaction were assessed using structured questionnaires. Actual numbers of new referrals were compared to projections based on historical data. Waiting list growth was compared to other specialties and other commissioning areas. Waiting times to initial treatment were monitored. RESULTS Over 3300 patients were enrolled and > 90% of dialogues were resolved within 36 hours. Clinician and patient satisfaction were high. Frequently asked questions and conditions were highlighted by dermatologists to design and deliver an educational event for primary care clinicians that was well received. Waiting list growth for dermatology patients in the commissioning area was smaller than for other major specialties, and generally smaller than growth for dermatology waiting lists commissioned by other NHS commissioners. There was no negative impact on the urgent priority (cancer pathway) waiting list. CONCLUSION The DDPS was satisfactory for clinicians and patients and coincided with lower growth in dermatology waiting lists than might otherwise have been expected.
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Thermoresponsive Poly( N, N'-dimethylacrylamide)-Based Diblock Copolymer Worm Gels via RAFT Solution Polymerization: Synthesis, Characterization, and Cell Biology Applications. Biomacromolecules 2023; 24:4285-4302. [PMID: 37616242 PMCID: PMC10498450 DOI: 10.1021/acs.biomac.3c00635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/09/2023] [Indexed: 08/26/2023]
Abstract
RAFT solution polymerization is used to polymerize 2-hydroxypropyl methacrylate (HPMA). The resulting PHPMA precursor is then chain-extended using N,N'-dimethylacrylamide (DMAC) to produce a series of thermoresponsive PHPMA-PDMAC diblock copolymers. Such amphiphilic copolymers can be directly dispersed in ice-cold water and self-assembled at 20 °C to form spheres, worms, or vesicles depending on their copolymer composition. Construction of a pseudo-phase diagram is required to identify the pure worm phase, which corresponds to a rather narrow range of PDMAC DPs. Such worms form soft, free-standing gels in aqueous solution at around ambient temperature. Rheology studies confirm the thermoresponsive nature of such worms, which undergo a reversible worm-to-sphere on cooling below ambient temperature. This morphological transition leads to in situ degelation, and variable temperature 1H NMR studies indicate a higher degree of (partial) hydration for the weakly hydrophobic PHPMA chains at lower temperatures. The trithiocarbonate end-group located at the end of each PDMAC chain can be removed by treatment with excess hydrazine. The resulting terminal secondary thiol group can form disulfide bonds via coupling, which produces PHPMA-PDMAC-PHPMA triblock copolymer chains. Alternatively, this reactive thiol group can be used for conjugation reactions. A PHPMA141-PDMAC36 worm gel was used to store human mesenchymal stem cells (MSCs) for up to three weeks at 37 °C. MSCs retrieved from this gel subsequently underwent proliferation and maintained their ability to differentiate into osteoblastic cells.
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Elastomeric Porous Poly(glycerol sebacate) Methacrylate (PGSm) Microspheres as 3D Scaffolds for Chondrocyte Culture and Cartilage Tissue Engineering. Int J Mol Sci 2023; 24:10445. [PMID: 37445620 DOI: 10.3390/ijms241310445] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
Cartilage defects can be difficult to treat; therefore, tissue engineering of cartilage is emerging as a promising potential therapy. One interesting area of research explores the delivery of cells to the cartilage defect via scaffold-based cell delivery vehicles and microsurgery. This study explores the use of novel poly(glycerol sebacate) methacrylate (PGSm)-polymerised high internal phase emulsion (polyHIPE) microspheres as scaffolds with embedded cells for cartilage tissue engineering. Porous microsphere scaffolds (100 µm-1 mm diameter) were produced from emulsions consisting of water and a methacrylate-based photocurable resin of poly(glycerol sebacate). These resins were used in conjunction with a T-junction fluidic device and an ultraviolet (UV) curing lamp to produce porous microspheres with a tuneable size. This technique produced biodegradable PGSm microspheres with similar mechanical properties to cartilage. We further explore these microspheres as scaffolds for three-dimensional culture of chondrocytes. The microspheres proved to be very efficient scaffolds for primary chondrocyte culture and were covered by a dense extracellular matrix (ECM) network during the culture period, creating a tissue disk. The presence of glycosaminoglycans (GAGs) and collagen-II was confirmed, highlighting the utility of the PGSm microspheres as a delivery vehicle for chondrocytes. A number of imaging techniques were utilised to analyse the tissue disk and develop methodologies to characterise the resultant tissue. This study highlights the utility of porous PGSm microspheres for cartilage tissue engineering.
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MRI findings in a cat with diffuse cerebellitis. J Small Anim Pract 2023; 64:421-422. [PMID: 36973866 DOI: 10.1111/jsap.13595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 11/16/2022] [Accepted: 01/24/2023] [Indexed: 03/29/2023]
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Third international challenge to model the medium- to long-range transport of radioxenon to four Comprehensive Nuclear-Test-Ban Treaty monitoring stations. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 255:106968. [PMID: 36148707 DOI: 10.1016/j.jenvrad.2022.106968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/08/2022] [Accepted: 07/15/2022] [Indexed: 06/16/2023]
Abstract
In 2015 and 2016, atmospheric transport modeling challenges were conducted in the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, however, with a more limited scope with respect to emission inventories, simulation period and number of relevant samples (i.e., those above the Minimum Detectable Concentration (MDC)) involved. Therefore, a more comprehensive atmospheric transport modeling challenge was organized in 2019. Stack release data of Xe-133 were provided by the Institut National des Radioéléments/IRE (Belgium) and the Canadian Nuclear Laboratories/CNL (Canada) and accounted for in the simulations over a three (mandatory) or six (optional) months period. Best estimate emissions of additional facilities (radiopharmaceutical production and nuclear research facilities, commercial reactors or relevant research reactors) of the Northern Hemisphere were included as well. Model results were compared with observed atmospheric activity concentrations at four International Monitoring System (IMS) stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions for evaluation of the participants' runs. Participants were prompted to work with controlled and harmonized model set-ups to make runs more comparable, but also to increase diversity. It was found that using the stack emissions of IRE and CNL with daily resolution does not lead to better results than disaggregating annual emissions of these two facilities taken from the literature if an overall score for all stations covering all valid observed samples is considered. A moderate benefit of roughly 10% is visible in statistical scores for samples influenced by IRE and/or CNL to at least 50% and there can be considerable benefit for individual samples. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12-24 h) undoubtedly are in contrast to and reduce the benefit of high-quality IRE and CNL stack data. Complementary best estimates for remaining emitters push the scores up by 18% compared to just considering IRE and CNL emissions alone. Despite the efforts undertaken the full multi-model ensemble built is highly redundant. An ensemble based on a few arbitrary runs is sufficient to model the Xe-133 background at the stations investigated. The effective ensemble size is below five. An optimized ensemble at each station has on average slightly higher skill compared to the full ensemble. However, the improvement (maximum of 20% and minimum of 3% in RMSE) in skill is likely being too small for being exploited for an independent period.
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It's time for a minimum synoptic operation template in patients undergoing laparoscopic cholecystectomy: a systematic review. World J Emerg Surg 2022; 17:15. [PMID: 35296354 PMCID: PMC8928637 DOI: 10.1186/s13017-022-00411-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 01/07/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Despite the call to enhance accuracy and value of operation records few international recommended minimal standards for operative notes documentation have been described. This study undertook a systematic review of existing operative reporting systems for laparoscopic cholecystectomy (LC) to fashion a comprehensive, synoptic operative reporting template for the future. METHODS A search for all relevant articles was conducted using PubMed version of Medline, Scopus and Web of Science databases in June 2021, for publications from January 1st 2011 to October 25th 2021, using the keywords: laparoscopic cholecystectomy AND operation notes OR operative notes OR proforma OR documentation OR report OR narrative OR audio-visual OR synoptic OR digital. Two reviewers (NOC, GMC) independently assessed each published study using a MINORS score of ≥ 16 for comparative and ≥ 10 for non-comparative for inclusion. This systematic review followed PRISMA guidelines and was registered with PROSPERO. Synoptic operative templates from published data were assimilated into one "ideal" laparoscopic operative report template following international input from the World Society of Emergency Surgery board. RESULTS A total of 3567 articles were reviewed. Following MINORS grading 25 studies were selected spanning 14 countries and 4 continents. Twenty-two studies were prospective. A holistic overview of the operative procedure documentation was reported in 6/25 studies and a further 19 papers dealt with selective surgical aspects of LC. A unique synoptic LC operative reporting template was developed and translated into Chinese/Mandarin, French and Arabic. CONCLUSION This systematic review identified a paucity of publications dealing with operative reporting of LC. The proposed new template may be integrated digitally with hospitals' medical systems and include additional narrative text and audio-visual data. The template may help define new OR (operating room) recording standards and impact on care for patients undergoing LC.
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P.324RNAscope multiplex in situ hybridisation reveals unique patterns of dystrophin isoform expression in the developing mammalian foetus. Neuromuscul Disord 2019. [DOI: 10.1016/j.nmd.2019.06.438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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34AFTER A FALL: THE USE OF A PRO FORMA TO IMPROVE ASSESSMENT. Age Ageing 2019. [DOI: 10.1093/ageing/afz055.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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38HEAD OVER HEELS. Age Ageing 2019. [DOI: 10.1093/ageing/afz055.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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2HEAD OVER HEELS. Age Ageing 2019. [DOI: 10.1093/ageing/afy211.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Alginate-based hydrogels functionalised at the nanoscale using layer-by-layer assembly for potential cartilage repair. Biomater Sci 2018; 5:1922-1931. [PMID: 28752866 DOI: 10.1039/c7bm00525c] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Injuries to articular cartilage are frequently difficult to repair, in part because of the poor regenerative capacity of this tissue. To date, no successful system for complete regeneration of the most challenging cartilage defects has been demonstrated. The aim of this work was to develop functionalised hydrogels at the nanoscale by Layer-by-Layer (LbL) assembly to promote cartilage healing. Hydrogels, based on sodium alginate (NaAlg) and gelatin (G), were prepared by an external gelation method consisting of CaCl2 diffusion and genipin addition for G crosslinking. Successively, hydrogels were coated with G to obtain a positive charge on the surface, then functionalised by LbL assembly to create 16 nanolayers, based on poly(styrene sulfonate)/poly(allyl amine) (PSS/PAH), including a specific peptide sequence (CTATVHL) and transforming growth factors β1 (TGF-β1). Physico-chemical properties were evaluated by XPS, ATR-FTIR and rheological analyses while in vitro cytocompatibility was studied using bovine articular chondrocytes (BAC). XPS spectra showed N1s and S2p peaks, indicating that PAH and PSS have been introduced with success. ATR-FTIR indicated the specific PAH and PSS absorption peaks. Finally, the biomolecule incorporation influenced positively the processes of BAC adhesion and proliferation, and glycosamynoglycan secretion. The functionalised alginate-based hydrogels described here are ideally suited to chondral regeneration in terms of their integrity, stability, and cytocompatibility.
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Maternal and fetal genetic contribution to gestational weight gain. Int J Obes (Lond) 2018; 42:775-784. [PMID: 28990592 PMCID: PMC5784805 DOI: 10.1038/ijo.2017.248] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 08/27/2017] [Accepted: 09/03/2017] [Indexed: 12/25/2022]
Abstract
BACKGROUND Clinical recommendations to limit gestational weight gain (GWG) imply high GWG is causally related to adverse outcomes in mother or offspring, but GWG is the sum of several inter-related complex phenotypes (maternal fat deposition and vascular expansion, placenta, amniotic fluid and fetal growth). Understanding the genetic contribution to GWG could help clarify the potential effect of its different components on maternal and offspring health. Here we explore the genetic contribution to total, early and late GWG. PARTICIPANTS AND METHODS A genome-wide association study was used to identify maternal and fetal variants contributing to GWG in up to 10 543 mothers and 16 317 offspring of European origin, with replication in 10 660 mothers and 7561 offspring. Additional analyses determined the proportion of variability in GWG from maternal and fetal common genetic variants and the overlap of established genome-wide significant variants for phenotypes relevant to GWG (for example, maternal body mass index (BMI) and glucose, birth weight). RESULTS Approximately 20% of the variability in GWG was tagged by common maternal genetic variants, and the fetal genome made a surprisingly minor contribution to explain variation in GWG. Variants near the pregnancy-specific beta-1 glycoprotein 5 (PSG5) gene reached genome-wide significance (P=1.71 × 10-8) for total GWG in the offspring genome, but did not replicate. Some established variants associated with increased BMI, fasting glucose and type 2 diabetes were associated with lower early, and higher later GWG. Maternal variants related to higher systolic blood pressure were related to lower late GWG. Established maternal and fetal birth weight variants were largely unrelated to GWG. CONCLUSIONS We found a modest contribution of maternal common variants to GWG and some overlap of maternal BMI, glucose and type 2 diabetes variants with GWG. These findings suggest that associations between GWG and later offspring/maternal outcomes may be due to the relationship of maternal BMI and diabetes with GWG.
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How Is Rectal Cancer Managed: a Survey Exploring Current Practice Patterns in Canada. J Gastrointest Cancer 2018; 50:260-268. [DOI: 10.1007/s12029-018-0064-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Evidenced Based Drug-Drug Interaction Alerts in an E-Prescribing System. Clin Ther 2017. [DOI: 10.1016/j.clinthera.2017.05.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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The relationship between particle morphology and rheological properties in injectable nano-hydroxyapatite bone graft substitutes. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 75:1083-1090. [DOI: 10.1016/j.msec.2017.02.170] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/25/2017] [Accepted: 02/28/2017] [Indexed: 12/01/2022]
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* Substituted Borosilicate Glasses with Improved Osteogenic Capacity for Bone Tissue Engineering. Tissue Eng Part A 2017; 23:1331-1342. [PMID: 28346797 DOI: 10.1089/ten.tea.2016.0386] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Borosilicate bioactive glasses (BBGs) have shown the capacity to promote higher formation of new bone when compared with silicate bioactive glasses. Herein, we assessed the capacity of BBGs to induce osteogenic differentiation of bone marrow mesenchymal stem cells (BM-MSCs) as a function of their substituted divalent cations (Mg2+, Ca2+, Sr2+). To this purpose, we synthesized BBG particles by melt quenching. The cell viability, proliferation, and morphology (i.e., PrestoBlue®, PicoGreen®, and DAPI and Phalloidin stainings, respectively), as well as protein expression (i.e., alkaline phosphatase, ALP; osteopontin, OP; and osteocalcin, OC), of BM-MSCs in contact with BBGs were evaluated for 21 days. We observed an enhanced expression of bone-specific proteins (ALP, OP, and OC) and high mineralization of BM-MSCs under BBG-Mg and BBG-Sr-conditioned osteogenic media for concentrations of 20 and 50 mg/mL with low cytotoxic effects. Moreover, BBG-Sr, at a concentration of 50 mg/mL, was able to increase the mineralization and expression of the same bone-specific proteins even under basal medium conditions. These results indicated that the proposed BBGs improved osteogenic differentiation of BM-MSCs, therefore showing their potential as relevant biomaterials for bone tissue regeneration, not only by bonding to bone tissue but also by stimulating new bone formation.
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Physiological Fluid Flow Moderates Fibroblast Responses to TGF-β1. J Cell Biochem 2016; 118:878-890. [PMID: 27748539 DOI: 10.1002/jcb.25767] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/14/2016] [Indexed: 12/11/2022]
Abstract
Fibroblasts are the major cellular component of connective tissue and experience mechanical perturbations due to matrix remodelling and interstitial fluid movement. Transforming growth factor β1 (TGF-β1) can promote differentiation of fibroblasts in vitro to a contractile myofibroblastic phenotype characterised by the presence of α-smooth muscle actin (α-SMA) rich stress fibres. To study the role of mechanical stimulation in this process, we examined the response of primary human fibroblasts to physiological levels of fluid movement and its influence on fibroblast differentiation and responses to TGF-β1. We reported that in both oral and dermal fibroblasts, physiological levels of fluid flow induced widespread changes in gene expression compared to static cultures, including up-regulation of genes associated with TGFβ signalling and endocytosis. TGF-β1, activin A and markers of myofibroblast differentiation including α-SMA and collagen IA1 were also increased by flow but surprisingly the combination of flow and exogenous TGF-β1 resulted in reduced differentiation. Our findings suggest this may result from enhanced internalisation of caveolin and TGF-β receptor II. These findings suggest that a) low levels of fluid flow induce myofibroblast differentiation and b) fluid flow antagonises the fibroblast response to pro-differentiation signals such as TGF-β1. We propose that this may be a novel mechanism by which mechanical forces buffer responses to chemical signals in vivo, maintaining a context-specific fibroblast phenotype. J. Cell. Biochem. 118: 878-890, 2017. © 2016 Wiley Periodicals, Inc.
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Reinforcement of poly-l-lactic acid electrospun membranes with strontium borosilicate bioactive glasses for bone tissue engineering. Acta Biomater 2016; 44:168-77. [PMID: 27554018 DOI: 10.1016/j.actbio.2016.08.042] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/08/2016] [Accepted: 08/19/2016] [Indexed: 11/26/2022]
Abstract
UNLABELLED Herein, for the first time, we combined poly-l-lactic acid (PLLA) with a strontium borosilicate bioactive glass (BBG-Sr) using electrospinning to fabricate a composite bioactive PLLA membrane loaded with 10% (w/w) of BBG-Sr glass particles (PLLA-BBG-Sr). The composites were characterised by scanning electron microscopy (SEM) and microcomputer tomography (μ-CT), and the results showed that we successfully fabricated smooth and uniform fibres (1-3μm in width) with a homogeneous distribution of BBG-Sr microparticles (<45μm). Degradation studies (in phosphate buffered saline) demonstrated that the incorporation of BBG-Sr glass particles into the PLLA membranes increased their degradability and water uptake with a continuous release of cations. The addition of BBG-Sr glass particles enhanced the membrane's mechanical properties (69% higher Young modulus and 36% higher tensile strength). Furthermore, cellular in vitro evaluation using bone marrow-derived mesenchymal stem cells (BM-MSCs) demonstrated that PLLA-BBG-Sr membranes promoted the osteogenic differentiation of the cells as demonstrated by increased alkaline phosphatase activity and up-regulated osteogenic gene expression (Alpl, Sp7 and Bglap) in relation to PLLA alone. These results strongly suggest that the composite PLLA membranes reinforced with the BBG-Sr glass particles have potential as an effective biomaterial capable of promoting bone regeneration. STATEMENT OF SIGNIFICANCE PLLA membranes were reinforced with 10% (w/w) of strontium-bioactive borosilicate glass microparticles, and their capacity to induce the osteogenic differentiation of bone marrow mesenchymal stem cells (BM-MSCs) was evaluated. These membranes presented an increased: degradability, water uptake, Young modulus and tensile strength. We also demonstrated that these membranes are non-cytotoxic and promote the attachment of BM-MSCs. The addition of the glass microparticles into the PLLA membranes promoted the increase of ALP activity (under osteogenic conditions), as well as the BM-MSCs osteogenic differentiation as shown by the upregulation of Alpl, Sp7 and Bglap gene expression. Overall, we demonstrated that the reinforcement of PLLA with glass microparticles results in a biomaterial with the appropriate properties for the regeneration of bone tissue.
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Repair of bone defects in vivo using tissue engineered hypertrophic cartilage grafts produced from nasal chondrocytes. Biomaterials 2016; 112:313-323. [PMID: 27770634 DOI: 10.1016/j.biomaterials.2016.10.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 10/03/2016] [Accepted: 10/11/2016] [Indexed: 10/20/2022]
Abstract
The regeneration of large bone defects remains clinically challenging. The aim of our study was to use a rat model to use nasal chondrocytes to engineer a hypertrophic cartilage tissue which could be remodelled into bone in vivo by endochondral ossification. Primary adult rat nasal chondrocytes were isolated from the nasal septum, the cell numbers expanded in monolayer culture and the cells cultured in vitro on polyglycolic acid scaffolds in chondrogenic medium for culture periods of 5-10 weeks. Hypertrophic differentiation was assessed by determining the temporal expression of key marker genes and proteins involved in hypertrophic cartilage formation. The temporal changes in the genes measured reflected the temporal changes observed in the growth plate. Collagen II gene expression increased 6 fold by day 7 and was then significantly downregulated from day 14 onwards. Conversely, collagen X gene expression was detectable by day 14 and increased 100-fold by day 35. The temporal increase in collagen X expression was mirrored by increases in alkaline phosphatase gene expression which also was detectable by day 14 with a 30-fold increase in gene expression by day 35. Histological and immunohistochemical analysis of the engineered constructs showed increased chondrocyte cell volume (31-45 μm), deposition of collagen X in the extracellular matrix and expression of alkaline phosphatase activity. However, no cartilage mineralisation was observed in in vitro culture of up to 10 weeks. On subcutaneous implantation of the hypertrophic engineered constructs, the grafts became vascularised, cartilage mineralisation occurred and loss of the proteoglycan in the matrix was observed. Implantation of the hypertrophic engineered constructs into a rat cranial defect resulted in angiogenesis, mineralisation and remodelling of the cartilage tissue into bone. Micro-CT analysis indicated that defects which received the engineered hypertrophic constructs showed 38.48% in bone volume compared to 7.01% in the control defects. Development of tissue engineered hypertrophic cartilage to use as a bone graft substitute is an exciting development in regenerative medicine. This is a proof of principal study demonstrating the potential of nasal chondrocytes to engineer hypertrophic cartilage which will remodel into bone on in vivo transplantation. This approach to making engineered hypertrophic cartilage grafts could form the basis of a new potential future clinical treatment for maxillofacial reconstruction.
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Abstract B35: Modeling interstitial fluid movement in the tumor microenvironment: A role in fibroblast activation? Cancer Res 2016. [DOI: 10.1158/1538-7445.tme16-b35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: The tissue dynamics of a growing tumor differ from normal tissue, with increased matrix stiffness and mechanical pressure causing alterations in interstitial fluid movement in the tumor microenvironment (TME). This change in fluid flow is known to affect the ability of chemotherapeutic drugs to penetrate tumors, but the effect of flow on the phenotype of cells of the tumor microenvironment has not been studied. The predominant cell type of the TME, the fibroblast, is known to become activated to a pro-tumorigenic phenotype upon exposure to factors such as TGF-β1 released by cancer cells, immune cells and also by mechanical forces. The effect of fluid flow on the fibroblast phenotype, however, remains undetermined.
Objectives: We hypothesize that stromal fibroblasts are activated by interstitial fluid flow and thereby promote tumor growth. We aim to investigate this by studying the markers of fibroblast activation under mechanically relevant interstitial fluid flow conditions.
Methods: Normal oral (NOF) and dermal (NHDF) fibroblasts were plated on collagen coated Thermonox cover slips, transferred into Quasi-vivo bioreactors and subjected to flow (150 μl/min) for 24 h. Expression of fibroblast activation markers, α-SMA and collagen IA1, were assessed by qPCR and microarray gene expression analysis was performed using RNA harvested from the cells. α-SMA and phospho-SMAD3 protein expression was studied using immunofluorescence and western blot.
Results: Media flow altered gene expression in oral and skin fibroblasts, increasing expression of α-SMA by 5.2 fold (NHDF) and 2.6 fold (NOF) and collagen IA by 2.9 fold (NHDF) and 3.2 fold (NOF) when compared to cells in static culture. TGF-β1 stimulation in the presence of flow decreased expression of these markers, but increased them in static culture. In dermal fibroblasts, flow stimulated α-SMA protein expression and translocation of phosphorylated SMAD3 to the cell nucleus and enhanced the expression of caveolin-1 alpha, which regulates the TGF-β1 pathway. Dermal fibroblasts exposed to flow revealed significant variations in expression of 16348 genes that may regulate the TGF-β1 pathway.
Conclusion: Flow activates fibroblasts to a similar extent as TGF-β1 stimulated static cultures. Concurrent TGF-β1 treatment with flow, however, does not cause fibroblast activation. It is possible that TGF-β1 stimulation of fibroblasts under flow leads to caveolin-mediated endocytosis of the receptor or negative regulation of SMAD intracellular signaling pathways resulting in decreased expression of activation markers. Regardless of their origin (oral or dermal), fibroblasts respond to even modest flow conditions. Our findings suggest caution should be used when extrapolating findings from static models to in vivo conditions. It further prompts exploration of novel anti-tumor strategies that alter the physical properties of the tumor microenvironment.
Citation Format: Sadhvi Nithiananthan, Aileen Crawford, Daniel W. Lambert, Simon Whawell. Modeling interstitial fluid movement in the tumor microenvironment: A role in fibroblast activation? [abstract]. In: Proceedings of the AACR Special Conference: Function of Tumor Microenvironment in Cancer Progression; 2016 Jan 7–10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2016;76(15 Suppl):Abstract nr B35.
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Fatal meningoencephalitis secondary to nematode Halicephalobus gingivalis infection in a human. Pathology 2016. [DOI: 10.1016/j.pathol.2015.12.322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Expression of Cannabinoid Receptors in Human Osteoarthritic Cartilage: Implications for Future Therapies. Cannabis Cannabinoid Res 2016; 1:3-15. [PMID: 28861474 PMCID: PMC5576594 DOI: 10.1089/can.2015.0001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Introduction: Cannabinoids have shown to reduce joint damage in animal models of arthritis and reduce matrix metalloproteinase expression in primary human osteoarthritic (OA) chondrocytes. The actions of cannabinoids are mediated by a number of receptors, including cannabinoid receptors 1 and 2 (CB1 and CB2), G-protein-coupled receptors 55 and 18 (GPR55 and GPR18), transient receptor potential vanilloid-1 (TRPV1), and peroxisome proliferator-activated receptors alpha and gamma (PPARα and PPARγ). However, to date very few studies have investigated the expression and localization of these receptors in human chondrocytes, and expression during degeneration, and thus their potential in clinical applications is unknown. Methods: Human articular cartilage from patients with symptomatic OA was graded histologically and the expression and localization of cannabinoid receptors within OA cartilage and underlying bone were determined immunohistochemically. Expression levels across regions of cartilage and changes with degeneration were investigated. Results: Expression of all the cannabinoid receptors investigated was observed with no change with grade of degeneration seen in the expression of CB1, CB2, GPR55, PPARα, and PPARγ. Conversely, the number of chondrocytes within the deep zone of cartilage displaying immunopositivity for GPR18 and TRPV1 was significantly decreased in degenerate cartilage. Receptor expression was higher in chondrocytes than in osteocytes in the underlying bone. Conclusions: Chondrocytes from OA joints were shown to express a wide range of cannabinoid receptors even in degenerate tissues, demonstrating that these cells could respond to cannabinoids. Cannabinoids designed to bind to receptors inhibiting the catabolic and pain pathways within the arthritic joint, while avoiding psychoactive effects, could provide potential arthritis therapies.
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Metabolic effects of Carbon Dioxide (CO2) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo2) and End Tidal Carbon Dioxide (EtCO2). THE CENTRAL AFRICAN JOURNAL OF MEDICINE 2015; 61:61-65. [PMID: 29144063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
BACKGROUND Acid base alterations occur during laparoscopy with carbon dioxide insufflation. The purpose of this study was to investigate the effects of low tidal volume ventilation on acid base status during pneumoperitonium. MATERIALS AND METHODS 30 patients undergoing laparoscopic surgery under General Anaesthesia were ventilated with tidal volume of 6 ml/kg and respiratory rate of 12 breaths/minute. Arterial blood gas analysis was done before, during and after C02 pneumoperitoneum. Arterial haemoglobin oxygen saturation by pulse oximetry (SPO2) and EtC02 were monitored continuously throughout the laparoscopy. Respiratory adjustments were done for EtCO2 levels above 60mmHg or SPO2 below 92% or adverse haemodynamic changes. RESULTS low tidal volume ventilation during pneumoperitoneum resulted in a significant elevation in PaCO2 (p<0.001) and a fall of pH (p <0.001), ion bicarbonate (HCO3-) (p = 0.011), and base excess (ABE) (p <0.001). A correlation was found between the EtCO2 and PaCO2 during pneumoperitoneum. Oxygenation was well maintained during pneumoperitoneum. No ventilatory adjustments were instituted on any of the patients as they maintained EtCO2 below 60mmHg throughout pneumoperitoneum. CONCLUSION Ventilation with low tidal volume during pneumoperitoneum causes a mixed respiratory and metabolic acidosis. EtCO2 is still a good non-invasive monitor for estimation of PaCO2 during low tidal volume ventilation during pneumoperitoneum.
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Risk evaluation mitigation strategy: impact of application of the Food and Drug Adminstration's strategy on use of erythropoiesis-stimulating agents and transfusion in patients with chemotherapy-induced anaemia. J Clin Pharm Ther 2015; 40:299-303. [DOI: 10.1111/jcpt.12269] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/12/2015] [Indexed: 11/29/2022]
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Development of an intervention to improve parental recognition of childhood overweight. Appetite 2015. [DOI: 10.1016/j.appet.2014.12.118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Fabrication of drug-loaded anti-infective guided tissue regeneration membrane with adjustable biodegradation property. Colloids Surf B Biointerfaces 2015; 135:846-854. [PMID: 25847456 DOI: 10.1016/j.colsurfb.2015.03.031] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/09/2015] [Accepted: 03/10/2015] [Indexed: 12/31/2022]
Abstract
For guided tissue regeneration (GTR) membrane, synchronization of the membrane biodegradation rate and tissue regeneration rate is important. Besides, the major reason for GTR membrane failure in clinical application is infection which can be prevented by loading anti-bacterial drug. To realize the consistency in membrane degradation rate and tissue regeneration rate of the anti-infective membrane, we developed metronidazole-loaded electrospun poly(ɛ-caprolactone)-gelatin nanofiber membranes with different poly(ɛ-caprolactone)/gelatin ratios (95:5, 90:10, 80:20, 70:30, 60:40, and 50:50). Homogeneous nanofibers were successfully fabricated. The mechanical strength of the membranes increased with the poly(ɛ-caprolactone) content, while the hydrophilicity decreased. The controlled and sustained release of metronidazole from all the membranes prevented the colonization of anaerobic bacteria. At all poly(ɛ-caprolactone)/gelatin ratios, all the membranes presented good biocompatibility while the increase of gelatin content resulted in enhanced cell adhesion and proliferation. Subcutaneous implantation in rabbits for 8 months demonstrated that all the membranes showed good biocompatibility without infection. Both in vitro and in vivo results showed that the biodegradation rate of the membranes was accelerated with the increase of gelatin content. The biodegradation rate and biocompatibility of the membranes can be adjusted by changing the PCL/gelatin ratio. The optimal membrane can be chosen based on the patient and tissue type to realize the synchronization of membrane degradation with tissue regeneration for the best treatment effect.
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The osteogenic response of mesenchymal stromal cells to strontium-substituted bioactive glasses. J Tissue Eng Regen Med 2015; 9:619-31. [PMID: 25757935 PMCID: PMC5053305 DOI: 10.1002/term.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/12/2014] [Accepted: 12/17/2014] [Indexed: 01/10/2023]
Abstract
Bioactive glasses are known to stimulate bone healing, and the incorporation of strontium has the potential to increase their potency. In this study, calcium oxide in the 45S5 bioactive glass composition was partially (50%, Sr50) or fully (100%, Sr100) substituted with strontium oxide on a molar basis. The effects of the substitution on bioactive glass properties were studied, including density, solubility, and in vitro cytotoxicity. Stimulation of osteogenic differentiation was investigated using mesenchymal stromal cells obtained from rat bone marrow. Strontium substitution resulted in altered physical properties including increased solubility. Statistically significant reductions in cell viability were observed with the addition of bioactive glass powders to culture medium. Specifically, addition of ≥ 13.3 mg/ml of 45S5 bioactive glass or Sr50, or ≥ 6.7 mg/ml of Sr100, resulted in significant inhibition. Real‐time PCR analyses detected the upregulation of genes associated with osteoblastic differentiation in the presence of all bioactive glass compositions. Some genes, including Alpl and Bglap, were further stimulated in the presence of Sr50 and Sr100. It was concluded that strontium‐substituted bioactive glasses promoted osteogenesis in a differentiating bone cell culture model and, therefore, have considerable potential for use as improved bioactive glasses for bone tissue regeneration. © 2015 The Authors. Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.
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Poly(2-ethyl-(2-pyrrolidone) methacrylate) and hyaluronic acid–based hydrogels for the engineering of a cartilage-like tissue using bovine articular chondrocytes. J BIOACT COMPAT POL 2014. [DOI: 10.1177/0883911514555609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Poly(2-ethyl-(2-pyrrolidone)methacrylate)–hyaluronic acid hydrogels based on the free radical polymerization of 2-ethyl-(2-pyrrolidone)methacrylate combined with hyaluronic acid, using N,N′-methylenebisacrylamide or triethylene glycol dimethacrylate, as cross-linking agents, were considered for tissue engineering applications. Bovine articular chondrocytes were seeded onto the poly(2-ethyl-(2-pyrrolidone)methacrylate)–hyaluronic acid hydrogels, under orbital agitation, for a total of 40 days. The engineered cell-constructs were characterized according to cell proliferation, morphology and distribution as well as the biochemical composition of the tissue formed. The chondrocytes were found to be attached and presented a typical spherical morphology. Cells were able to proliferate and synthesize a hyaline-like matrix rich in glycosaminoglycans and collagen type II which were mainly located on the superficial area. Increased content of individual components poly(2-ethyl-(2-pyrrolidone)methacrylate) and hyaluronic acid, in triethylene glycol dimethacrylate–cross-linked networks led to enhanced cell distribution and total glycosaminoglycans content, supporting their potential application for the repair of cartilaginous tissues.
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Drug loaded homogeneous electrospun PCL/gelatin hybrid nanofiber structures for anti-infective tissue regeneration membranes. Biomaterials 2014; 35:9395-405. [PMID: 25134855 DOI: 10.1016/j.biomaterials.2014.07.060] [Citation(s) in RCA: 234] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 07/28/2014] [Indexed: 12/13/2022]
Abstract
Infection is the major reason for guided tissue regeneration/guided bone regeneration (GTR/GBR) membrane failure in clinical application. In this work, we developed GTR/GBR membranes with localized drug delivery function to prevent infection by electrospinning of poly(ε-caprolactone) (PCL) and gelatin blended with metronidazole (MNA). Acetic acid (HAc) was introduced to improve the miscibility of PCL and gelatin to fabricate homogeneous hybrid nanofiber membranes. The effects of the addition of HAc and the MNA content (0, 1, 5, 10, 20, 30, and 40 wt.% of polymer) on the properties of the membranes were investigated. The membranes showed good mechanical properties, appropriate biodegradation rate and barrier function. The controlled and sustained release of MNA from the membranes significantly prevented the colonization of anaerobic bacteria. Cells could adhere to and proliferate on the membranes without cytotoxicity until the MNA content reached 30%. Subcutaneous implantation in rabbits for 8 months demonstrated that MNA-loaded membranes evoked a less severe inflammatory response depending on the dose of MNA than bare membranes. The biodegradation time of the membranes was appropriate for tissue regeneration. These results indicated the potential for using MNA-loaded PCL/gelatin electrospun membranes as anti-infective GTR/GBR membranes to optimize clinical application of GTR/GBR strategies.
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Remote-Controlled Automatic Injection Versus Manual Injection in Ictal SPECT of Seizure Patients: Experience from a Children's Hospital. J Nucl Med Technol 2014; 42:161-2. [DOI: 10.2967/jnmt.114.145854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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High chondrogenic potential of synovial fluid-derived mesenchymal stromal cells. Cytotherapy 2014; 16:1595-1596. [PMID: 24980656 DOI: 10.1016/j.jcyt.2014.04.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 04/09/2014] [Accepted: 04/29/2014] [Indexed: 01/09/2023]
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Fabrication and evaluation of electrospun PCL–gelatin micro-/nanofiber membranes for anti-infective GTR implants. J Mater Chem B 2014; 2:6867-6877. [DOI: 10.1039/c4tb00737a] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Infection is the major reason for GTR/GBR membrane failure in clinical applications.
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Cannabinoid WIN-55,212-2 mesylate inhibits interleukin-1β induced matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase expression in human chondrocytes. Osteoarthritis Cartilage 2014; 22:133-44. [PMID: 24211233 DOI: 10.1016/j.joca.2013.10.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 10/22/2013] [Accepted: 10/26/2013] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Interleukin-1β (IL-1β) is involved in the up-regulation of matrix metalloproteinases (MMPs) leading to cartilage degradation. Cannabinoids are anti-inflammatory and reduce joint damage in animal models of arthritis. This study aimed to determine a mechanism whereby the synthetic cannabinoid WIN-55,212-2 mesylate (WIN-55) may inhibit cartilage degradation. METHODS Effects of WIN-55 were studied on IL-1β stimulated production of MMP-3 and -13 and their inhibitors TIMP-1 and -2 in human chondrocytes. Chondrocytes were obtained from articular cartilage of patients undergoing total knee replacement. Chondrocytes were grown in monolayer and 3D alginate bead cultures. Real-time polymerase chain reaction (PCR) was used to determine the gene expression of MMP-3, -13, TIMP-1 and -2 and Enzyme Linked Immunosorbent Assay (ELISA) to measure the amount of MMP-3 and MMP-13 protein released into media. Immunocytochemistry was used to investigate the expression of cannabinoid receptors in chondrocyte cultures. RESULTS Treatment with WIN-55 alone or in combination with IL-1β, decreased or abolished MMP-3, -13, TIMP-1 and -2 gene expression in human chondrocyte monolayer and alginate bead cultures in both a concentration and time dependent manner. WIN-55 treatment alone, and in combination with IL-1β, reduced MMP-3 and -13 protein production by chondrocytes cultured in alginate beads. Immunocytochemistry demonstrated the expression of cannabinoid receptors in chondrocyte cultures. CONCLUSION Cannabinoid WIN-55 can reduce both basal and IL-1β stimulated gene and protein expression of MMP-3 and -13. However WIN-55 also decreased basal levels of TIMP-1 and -2 mRNA. These actions of WIN-55 suggest a mechanism by which cannabinoids may act to prevent cartilage breakdown in arthritis.
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Mineralization of porous hydrogels based on semi-interpenetrated networks of poly[2-ethyl(2-pyrrolidone) methacrylate] and hyaluronic acid in simulated body fluid. J BIOACT COMPAT POL 2013. [DOI: 10.1177/0883911513494618] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Poly[2-ethyl(2-pyrrolidone) methacrylate] and hyaluronic acid hydrogels were synthesized via free-radical polymerization of 2-ethyl(2-pyrrolidone) methacrylate, hyaluronic acid and different crosslinkers. The ability of these hydrogels to induce apatite formation by incubating in simulated body fluid was investigated. The effect of hyaluronic acid content, crosslinkers and immersion time on mineralization behaviour and interface properties as well as the metabolic activity of different cultured cells were also determined. The bioactivity of the poly[2-ethyl(2-pyrrolidone) methacrylate] and hyaluronic acid hydrogels along with cell viability data indicated their potential application in bone tissue engineering.
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Predicting drug-induced hepatotoxicity in zebrafish larvae. Toxicol Lett 2013. [DOI: 10.1016/j.toxlet.2013.06.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Scotland's Knowledge Network: translating knowledge into action to improve quality of care. Scott Med J 2013; 57:221-4. [PMID: 23138580 DOI: 10.1258/smj.2012.012122] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Knowledge Network (www.knowledge.scot.nhs.uk) is Scotland's online knowledge service for health and social care. It is designed to support practitioners to apply knowledge in frontline delivery of care, helping to translate knowledge into better health-care outcomes through safe, effective, person-centred care. The Knowledge Network helps to combine the worlds of evidence-based practice and quality improvement by providing access to knowledge about the effectiveness of clinical interventions ('know-what') and knowledge about how to implement this knowledge to support individual patients in working health-care environments ('know-how'). An 'evidence and guidance' search enables clinicians to quickly access quality-assured evidence and best practice, while point of care and mobile solutions provide knowledge in actionable formats to embed in clinical workflow. This research-based knowledge is complemented by social networking services and improvement tools which support the capture and exchange of knowledge from experience, facilitating practice change and systems improvement. In these cases, the Knowledge Network supports key components of the knowledge-to-action cycle--acquiring, creating, sharing and disseminating knowledge to improve performance and innovate. It provides a vehicle for implementing the recommendations of the national Knowledge into Action review, which outlines a new national approach to embedding knowledge in frontline practice and systems improvement.
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Basic science * 232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function. Rheumatology (Oxford) 2012. [DOI: 10.1093/rheumatology/kes108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Novel Melt-Processable Chitosan–Polybutylene Succinate Fibre Scaffolds for Cartilage Tissue Engineering. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 22:773-88. [DOI: 10.1163/092050610x494604] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Louis Crawford. West J Med 2012. [DOI: 10.1136/bmj.d8092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Canadian Surgery Forum: Abstracts of presentations to the Annual Meetings of the Canadian Association of Bariatric Physicians and Surgeons, Canadian Association of General Surgeons, Canadian Association of Thoracic Surgeons, Canadian Hepato-Pancreato-Biliary Society, Canadian Society of Surgical Oncology, Canadian Society of Colon and Rectal Surgeons, London, Ont. Sept. 15-18, 2011. Can J Surg 2011; 54:S57-S104. [PMID: 35488394 PMCID: PMC3191910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023] Open
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Squeeze Pressure Bioreactor: A Hydrodynamic Bioreactor for Noncontact Stimulation of Cartilage Constructs. Tissue Eng Part C Methods 2011; 17:757-64. [DOI: 10.1089/ten.tec.2011.0002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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MDT's in cleft lip and palate: alveolar bone grafting, getting the process right. Br J Oral Maxillofac Surg 2011. [DOI: 10.1016/j.bjoms.2011.03.221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Genetic modification of chondrocytes using viral vectors. Methods Mol Biol 2011; 695:99-114. [PMID: 21042968 DOI: 10.1007/978-1-60761-984-0_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The use of isolated cells to construct engineered tissues provides the opportunity to genetically modify those cells prior to the formation of tissue. This should make it possible to create transgenic human model tissues that can be used to determine gene function as well as to identify or validate potential therapeutic targets. As proof of principle, we have used RNA interference to selectively suppress the expression of aggrecanase genes in human chondrocytes, in an attempt to determine which of these key enzymes have roles in arthritic cartilage destruction. This combination of gene targeting and tissue engineering we are using should be equally applicable to the identification of gene function in other biological systems.
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Plants with genetically modified events combined by conventional breeding: An assessment of the need for additional regulatory data. Food Chem Toxicol 2011; 49:1-7. [DOI: 10.1016/j.fct.2010.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 10/29/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022]
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Lentiviral shRNA knock-down of ADAMTS-5 and -9 restores matrix deposition in 3D chondrocyte culture. J Tissue Eng Regen Med 2010; 4:611-8. [PMID: 20568084 PMCID: PMC2988096 DOI: 10.1002/term.275] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Aggrecan is one of the two major constituents of articular cartilage, and during diseases such as osteoarthritis (OA) it is subject to degradation by proteolytic enzymes. The primary proteases responsible for aggrecan cleavage are the aggrecanases, identified as members of the ADAMTS family of proteases, which are upregulated in response to inflammatory stimuli. It is uncertain which of the six aggrecanases (ADAMTS-1, -4, -5, -8, -9 and -15) are primarily responsible for the degradation of aggrecan in human cartilage. Here we show that four of the six aggrecanases are expressed in immortalized chondrocyte cell-lines and can be upregulated in response to inflammatory cytokines. Using RNA interference, we demonstrate robust knock-down of ADAMTS-5 and -9 expression in these cells and, by culturing them on three-dimensional (3D) scaffolds, show that reduction in expression of ADAMTS-5 enzyme results in an increase in matrix deposition. These data suggest that the quality of tissue-engineered cartilage matrix might be improved by targeted depletion of aggrecanase expression. Moreover, this work also provides further evidence that ADAMTS-5 may be a therapeutic target in the treatment of arthritic disease.
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Abstract
Frequent atmospheric measurements of the anthropogenic compound methylchloroform that were made between 1978 and 1985 indicate that this species is continuing to increase significantly around the world. Reaction with the major atmospheric oxidant, the hydroxyl radical (OH), is the principal sink for this species. The observed mean trends for methylchloroform are 4.8, 5.4, 6.4, and 6.9 percent per year at Aldrigole (Ireland) and Cape Meares (Oregon), Ragged Point (Barbados), Point Matatula (American Samoa), and Cape Grim (Tasmania), respectively, from July 1978 to June 1985. These measured trends, combined with knowledge of industrial emissions, were used in an optimal estimation inversion scheme to deduce a globally averaged methylchloroform atmospheric lifetime of 6.3 (+ 1.2, -0.9) years (1sigma uncertainty) and a globally averaged tropospheric hydroxyl radical concentration of (7.7 +/- 1.4) x 10(5) radicals per cubic centimeter (1sigma uncertainty). These 7 years of gas chromatographic measurements, which comprise about 60,000 individual calibrated real-time air analyses, provide the most accurate estimates yet of the trends and lifetime of methylchloroform and of the global average for tropospheric hydroxyl radical levels. Accurate determination of hydroxyl radical levels is crucial to understanding global atmospheric chemical cycles and trends in the levels of trace gases such as methane.
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Chitosan/polyester-based scaffolds for cartilage tissue engineering: assessment of extracellular matrix formation. Acta Biomater 2010; 6:1149-57. [PMID: 19788942 DOI: 10.1016/j.actbio.2009.09.006] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Revised: 08/21/2009] [Accepted: 09/15/2009] [Indexed: 10/20/2022]
Abstract
Naturally derived polymers have been extensively used in scaffold production for cartilage tissue engineering. The present work aims to evaluate and characterize extracellular matrix (ECM) formation in two types of chitosan-based scaffolds, using bovine articular chondrocytes (BACs). The influence of these scaffolds' porosity, as well as pore size and geometry, on the formation of cartilagineous tissue was studied. The effect of stirred conditions on ECM formation was also assessed. Chitosan-poly(butylene succinate) (CPBS) scaffolds were produced by compression moulding and salt leaching, using a blend of 50% of each material. Different porosities and pore size structures were obtained. BACs were seeded onto CPBS scaffolds using spinner flasks. Constructs were then transferred to the incubator, where half were cultured under stirred conditions, and the other half under static conditions for 4 weeks. Constructs were characterized by scanning electron microscopy, histology procedures, immunolocalization of collagen type I and collagen type II, and dimethylmethylene blue assay for glycosaminoglycan (GAG) quantification. Both materials showed good affinity for cell attachment. Cells colonized the entire scaffolds and were able to produce ECM. Large pores with random geometry improved proteoglycans and collagen type II production. However, that structure has the opposite effect on GAG production. Stirred culture conditions indicate enhancement of GAG production in both types of scaffold.
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