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991.
Incorporation of resident macrophages in engineered tissues: Multiple cell type response to microenvironment controlled macrophage‐laden gelatine hydrogels
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Camille Dollinger Sait Ciftci Helena Knopf‐Marques Rabia Guner Amir M. Ghaemmaghami Christian Debry Julien Barthes Nihal Engin Vrana 《Journal of tissue engineering and regenerative medicine》2018,12(2):330-340
The success of tissue engineering strategy is strongly related to the inflammatory response, mainly through the activity of macrophages that are key cells in initial immune response to implants. For engineered tissues, the presence of resident macrophages can be beneficial for maintenance of homeostasis and healing. Thus, incorporation of macrophages in engineered tissues can facilitate the integration upon implantation. In this study, an in‐vitro model of interaction was developed between encapsulated naive monocytes, macrophages induced with M1/M2 stimulation and incoming cells for immune assisted tissue engineering applications. To mimic the wound healing cascade, naive THP‐1 monocytes, endothelial cells and fibroblasts were seeded on the gels as incoming cells. The interaction was first monitored in the absence of the gels. To mimic resident macrophages, THP‐1 cells were encapsulated in the presence or absence of IL‐4 to control their phenotype and then these hydrogels were seeded with incoming cells. Without encapsulation, activated macrophages induce apoptosis in endothelial cells. Once encapsulated no adverse effects were seen. Macrophage‐laden hydrogels attracted more endothelial cells and fibroblasts compared to monocytes‐laden hydrogels. The induction (M2 stimulation) of encapsulated macrophages did not change the overall number of attracted cells; but significantly affected their morphology. M1 stimulation by a defined media resulted in more secretion of both pro‐ and anti‐inflammatory cytokines compared to M2 stimulation. It was demonstrated that there is a distinct effect of encapsulated macrophages on the behaviour of the incoming cells; this effect can be harnessed to establish a microenvironment more prone to regeneration upon implantation. 相似文献
992.
Rahul Damodaran Prabha David Christian Evar Kraft Linda Harkness Birte Melsen Harikrishna Varma Prabha D. Nair Jorgen Kjems Moustapha Kassem 《Journal of tissue engineering and regenerative medicine》2018,12(3):e1537-e1548
There has been a growing demand for bone grafts for correction of bone defects in complicated fractures or tumours in the craniofacial region. Soft flexible membrane like material that could be inserted into defect by less invasive approaches; promote osteoconductivity and act as a barrier to soft tissue in growth while promoting bone formation is an attractive option for this region. Electrospinning has recently emerged as one of the most promising techniques for fabrication of extracellular matrix such as nano‐fibrous scaffolds that can serve as a template for bone formation. To overcome the limitation of cell penetration of electrospun scaffolds and improve on its osteoconductive nature, in this study, we fabricated a novel electrospun composite scaffold of polyvinyl alcohol (PVA)‐poly (ε) caprolactone (PCL)‐Hydroxyapatite based bioceramic (HAB), namely, PVA‐PCL‐HAB. The scaffold prepared by dual electrospinning of PVA and PCL with HAB overcomes reduced cell attachment associated with hydrophobic PCL by combination with a hydrophilic PVA and the HAB can contribute to enhance osteoconductivity. We characterized the physicochemical and biocompatibility properties of the new scaffold material. Our results indicate PVA‐PCL‐HAB scaffolds support attachment and growth of stromal stem cells; [human bone marrow skeletal (mesenchymal) stem cells and dental pulp stem cells]. In addition, the scaffold supported in vitro osteogenic differentiation and in vivo vascularized bone formation. Thus, PVA‐PCL‐HAB scaffold is a suitable potential material for therapeutic bone regeneration in dentistry and orthopaedics. 相似文献
993.
Slow Infusion of Low‐dose Ketamine Reduces Bothersome Side Effects Compared to Intravenous Push: A Double‐blind,Double‐dummy,Randomized Controlled Trial
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Eben J. Clattenburg MD MPH Christian Hailozian Daniel Haro Tina Yoo PharmD Stefan Flores MD Derex Louie PharmD BCPS Andrew A. Herring MD 《Academic emergency medicine》2018,25(9):1048-1052
Objective
We compared the analgesic efficacy and incidence of side effects when low‐dose (0.3 mg/kg) ketamine (LDK) is administered as a slow infusion (SI) over 15 minutes versus an intravenous push (IVP) over 1 minute.Methods
This was a prospective, randomized, double‐blind, double‐dummy, placebo‐controlled trial of adult ED patients presenting with moderate to severe pain (numerical rating scale [NRS] score ≥ 5). Patients received 0.3 mg/kg ketamine administered either as a SI or a IVP. Our primary outcome was the proportion of patients experiencing any psychoperceptual side effect over 60 minutes. A secondary outcome was incidence of moderate or greater psychoperceptual side effects. Additional outcomes included reduction in pain NRS scores at 60 minutes and percent maximum summed pain intensity difference (%SPID).Results
Fifty‐nine participants completed the study. A total of 86.2% of the IVP arm and 70.0% of the SI arm experienced any side effect (difference = 16.2%, 95% confidence interval [CI] = –5.4 to 37.8). We found a large reduction in moderate or greater psychoperceptual side effects with SI administration—75.9% reported moderate or greater side effects versus 43.4% in the SI arm (difference = 32.5%, 95% CI = 7.9 to 57.1). Additionally, the IVP arm experienced more hallucinations (n = 8, 27.6%) than the SI arm (SI n = 2, 6.7%, difference = 20.9%, 95% CI = 1.8 to 43.4). We found no significant differences in analgesic efficacy. At 60 minutes, the mean %SPID values in the IVP and SI arms were 39.9 and 33.5%, respectively, with a difference of 6.5% (95% CI = –5.8 to 18.7).Conclusion
Most patients who are administered LDK experience a psychoperceptual side effect regardless of administration via SI or IVP. However, patients receiving LDK as a SI reported significantly fewer moderate or greater psychoperceptual side effects and hallucinations with equivalent analgesia.994.
995.
Rein Ketelaars Christian Beekers Geert-Jan Van Geffen Gert Jan Scheffer Nico Hoogerwerf 《Prehospital emergency care》2018,22(4):406-413
Background: Patients in cardiac arrest must receive algorithm-based management such as basic life support and advanced (cardiac) life support. International guidelines dictate diagnosing and treating any factor that may have caused the arrest or may be complicating the resuscitation. Ultrasound may be of potential value in this process and can be used in a prehospital setting. The objective is to evaluate the use of prehospital ultrasound during traumatic and non-traumatic CPR and determine its impact on prehospital treatment decisions in a Dutch helicopter emergency medical service (HEMS). Methods: We conducted an observational study in cardiac arrest patients, of any cause, in whom the Nijmegen HEMS performed CPR with concurrent echocardiography. The participating physicians had to adhere to Advanced Life Support protocols as per standard operating procedure. Simultaneous with the interruptions of chest compressions to allow for heart rhythm analysis, ultrasound-trained HEMS physicians performed echocardiography according to study protocol. The HEMS nurse and physician recorded patient data and data on impacted (supported or altered) patient treatment decisions. Results: From February 2014 through November 2016, we included 56 patients who underwent 102 ultrasound examinations. Sixty-two (61%) ultrasound examinations impacted 78 treatment decisions in 49 patients (88%). The impacted treatment was related to termination of CPR in 32 (57%), fluid management (14%), drugs selection and doses (14%), and choice of destination hospital (5%). Causes of cardiac arrest included trauma (48%), cardiac (21%), medical (14%), asphyxia (9%), and other (7%). Conclusion: Prehospital echocardiography has an impact on patient treatment and may be a useful tool to support decision-making during CPR in a Dutch HEMS. 相似文献
996.
997.
998.
Nicole K. Paulk Katja Pekrun Erhua Zhu Sean Nygaard Bin Li Jianpeng Xu Kirk Chu Christian Leborgne Allison P. Dane Annelise Haft Yue Zhang Feijie Zhang Chris Morton Marcus B. Valentine Andrew M. Davidoff Amit C. Nathwani Federico Mingozzi Markus Grompe Mark A. Kay 《Molecular therapy》2018,26(1):289-303
999.
1000.
Christian Backer Mogensen Malene Bue Vilhelmsen Johanne Jepsen Lilian Keene Boye Maiken Hjuler Persson Florence Skyum 《BMC emergency medicine》2018,18(1):51