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991.
Optimized isolation and expansion of human airway epithelial basal cells from endobronchial biopsy samples 下载免费PDF全文
Kate H.C. Gowers Robert E. Hynds Ricky M. Thakrar Bernadette Carroll Martin A. Birchall Sam M. Janes 《Journal of tissue engineering and regenerative medicine》2018,12(1):e313-e317
Autologous airway epithelial cells have been used in clinical tissue‐engineered airway transplantation procedures with a view to assisting mucosal regeneration and restoring mucociliary escalator function. However, limited time is available for epithelial cell expansion due to the urgent nature of these interventions and slow epithelial regeneration has been observed in patients. Human airway epithelial cells can be expanded from small biopsies or brushings taken during bronchoscopy procedures, but the optimal mode of tissue acquisition from patients has not been investigated. Here, we compared endobronchial brushing and endobronchial biopsy samples in terms of their cell number and their ability to initiate basal epithelial stem cell cultures. We found that direct co‐culture of samples with 3T3‐J2 feeder cells in culture medium containing a Rho‐associated protein kinase inhibitor, Y‐27632, led to the selective expansion of greater numbers of basal epithelial stem cells during the critical early stages of culture than traditional techniques. Additionally, we established the benefit of initiating cell cultures from cell suspensions, either using brushing samples or through enzymatic digestion of biopsies, over explant culture. Primary epithelial cell cultures were initiated from endobronchial biopsy samples that had been cryopreserved before the initiation of cell cultures, suggesting that cryopreservation could eliminate the requirement for close proximity between the clinical facility in which biopsy samples are taken and the specialist laboratory in which epithelial cells are cultured. Overall, our results suggest ways to expedite epithelial cell preparation in future airway cell therapy or bioengineered airway transplantation procedures. 相似文献
992.
Nonunion fracture healing: Evaluation of effectiveness of demineralized bone matrix and mesenchymal stem cells in a novel sheep bone nonunion model 下载免费PDF全文
Barbara Dozza Francesca Salamanna Massimiliano Baleani Gianluca Giavaresi Annapaola Parrilli Lorenzo Zani Enrico Lucarelli Lucia Martini Milena Fini Davide Maria Donati 《Journal of tissue engineering and regenerative medicine》2018,12(9):1972-1985
Nonunion treatment has a high rate of success, although recalcitrant nonunion may determine the need for amputation. Therefore, new treatment options are continuously investigated in order to further reduce the risk of nonunion recurrence. This study aimed to (a) develop a new large animal model for bone atrophic nonunion and (b) compare the efficacy of demineralized bone matrix (DBM) and DBM in combination with mesenchymal stem cells (MSC) in the new nonunion model. The new model consists of a noncritical, full‐thickness segmental defect created in the sheep tibia, stabilized by an intramedullary nail, and involves the creation of a locally impaired blood supply achieved through periosteum excision and electrocauterization of the stump ends. Six weeks after defect creation, lack of hard tissue callus and established nonunion was observed in all operated tibiae both by radiographic and clinical evaluation. Nonunion was treated with allogeneic DBM or autologous MSC cultivated on DBM particles (DBM + MSC) for 1 day before implantation. Twelve weeks after treatment, radiographic, microtomographic, histologic, and histomorphometric analysis showed the formation of bone callus in DBM group, whereas the fracture healing appeared at an early stage in DBM + MSC group. Torsional strength and stiffness of the DBM group appeared higher than those of DBM + MSC group, although the differences were not statistically significant. In conclusion, a new sheep bone nonunion model resembling the complexity of the clinical condition was developed. DBM is an effective option for nonunion treatment, whereas MSC do not improve the healing process when cultivated on DBM particles before implantation. 相似文献
993.
A humanised tissue‐engineered bone model allows species‐specific breast cancer‐related bone metastasis in vivo 下载免费PDF全文
VMC Quent AV Taubenberger JC Reichert LC Martine JA Clements DW Hutmacher D Loessner 《Journal of tissue engineering and regenerative medicine》2018,12(2):494-504
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients. 相似文献
994.
Osteoarthritic human chondrocytes proliferate in 3D co‐culture with mesenchymal stem cells in suspension bioreactors 下载免费PDF全文
Madiha Khurshid Aillette Mulet‐Sierra Arindom Sen 《Journal of tissue engineering and regenerative medicine》2018,12(3):e1418-e1432
Osteoarthritis (OA) is a painful disease, characterized by progressive surface erosion of articular cartilage. The use of human articular chondrocytes (hACs) sourced from OA patients has been proposed as a potential therapy for cartilage repair, but this approach is limited by the lack of scalable methods to produce clinically relevant quantities of cartilage‐generating cells. Previous studies in static culture have shown that hACs co‐cultured with human mesenchymal stem cells (hMSCs) as 3D pellets can upregulate proliferation and generate neocartilage with enhanced functional matrix formation relative to that produced from either cell type alone. However, because static culture flasks are not readily amenable to scale up, scalable suspension bioreactors were investigated to determine if they could support the co‐culture of hMSCs and OA hACs under serum‐free conditions to facilitate clinical translation of this approach. When hACs and hMSCs (1:3 ratio) were inoculated at 20,000 cells/ml into 125‐ml suspension bioreactors and fed weekly, they spontaneously formed 3D aggregates and proliferated, resulting in a 4.75‐fold increase over 16 days. Whereas the apparent growth rate was lower than that achieved during co‐culture as a 2D monolayer in static culture flasks, bioreactor co‐culture as 3D aggregates resulted in a significantly lower collagen I to II mRNA expression ratio and more than double the glycosaminoglycan/DNA content (5.8 vs. 2.5 μg/μg). The proliferation of hMSCs and hACs as 3D aggregates in serum‐free suspension culture demonstrates that scalable bioreactors represent an accessible platform capable of supporting the generation of clinical quantities of cells for use in cell‐based cartilage repair. 相似文献
995.
Angiogenic potential of human mesenchymal stromal cell and circulating mononuclear cell cocultures is reflected in the expression profiles of proangiogenic factors leading to endothelial cell and pericyte differentiation 下载免费PDF全文
Katriina Joensuu Teuvo A. Hentunen Terhi J. Heino 《Journal of tissue engineering and regenerative medicine》2018,12(3):775-783
Endothelial progenitors found among the peripheral blood (PB) mononuclear cells (MNCs) are interesting cells for their angiogenic properties. Mesenchymal stromal cells (MSCs) in turn can produce proangiogenic factors as well as differentiate into mural pericytes, making MSCs and MNCs an attractive coculture setup for regenerative medicine. In this study, human bone marrow‐derived MSCs and PB‐derived MNCs were cocultured in basal or osteoblastic medium without exogenously supplied growth factors to demonstrate endothelial cell, pericyte and osteoblastic differentiation. The expression levels of various proangiogenic factors, as well as endothelial cell, pericyte and osteoblast markers in cocultures were determined by quantitative polymerase chain reaction. Immunocytochemistry for vascular endothelial growth factor receptor‐1 and α‐smooth muscle actin as well as staining for alkaline phosphatase were performed after 10 and 14 days. Messenger ribonucleic acid expression of endothelial cell markers was highly upregulated in both basal and osteoblastic conditions after 5 days of coculture, indicating an endothelial cell differentiation, which was supported by immunocytochemistry for vascular endothelial growth factor receptor‐1. Stromal derived factor‐1 and vascular endothelial growth factor were highly expressed in MSC‐MNC coculture in basal medium but not in osteoblastic medium. On the contrary, the expression levels of bone morphogenetic protein‐2 and angiopoietin‐1 were significantly higher in osteoblastic medium. Pericyte markers were highly expressed in both cocultures after 5 days. In conclusion, it was demonstrated endothelial cell and pericyte differentiation in MSC‐MNC cocultures both in basal and osteoblastic medium indicating a potential for neovascularization for tissue engineering applications. 相似文献
996.
Leila Taghiyar Samaneh Hosseini Fatemeh Safari Fatemeh Bagheri Nesa Fani Martin J. Stoddart Mauro Alini Mohamadreza Baghaban Eslaminejad 《Journal of tissue engineering and regenerative medicine》2018,12(9):1925-1943
Limb/digit amputation is a common event in humans caused by trauma, medical illness, or surgery. Although the loss of a digit is not lethal, it affects quality of life and imposes high costs on amputees. In recent years, the increasing interest in limb regeneration has led to enhanced scientific knowledge. However, the limited ability to develop functional limb regeneration in the clinical setting suggests that a challenging issue remains in limb regeneration. Recently, the emergence of regenerative engineering is a promising field to address this challenge and close the gap between science and clinical applications. Cell signalling and molecular mechanisms involved in the limb regeneration process have been extensively studied; however, there is still insufficient data on cell therapy and tissue engineering for limb regeneration. In this review, we intend to focus on therapeutic approaches for limb regeneration that are closely related to gene, immune, and stem cell therapies, as well as tissue engineering approaches that take into consideration the peculiar developmental properties of the limbs. In addition, we attempt to identify the challenges of these strategies for limb regeneration studies in terms of clinical settings and as a road map to accomplish the goal of functional human limb regeneration. 相似文献
997.
Background
Massage is a common treatment in complementary and integrative medicine. Deep tissue massage, a form of therapeutic massage, has become more and more popular in recent years. Hence, the use of massage generally and deep tissue massage specifically, should be evaluated as any other modality of therapy to establish its efficacy and safety.Aim
To determine the definitions used for deep tissue massage in the scientific literature and to review the current scientific evidence for its efficacy and safety.Methods
Narrative review.Results
There is no commonly accepted definition of deep tissue massage in the literature. The definition most frequently used is the intention of the therapist. We suggest separating the definitions of deep massage and deep tissue massage as follows: deep massage should be used to describe the intention of the therapist to treat deep tissue by using any form of massage and deep tissue massage should be used to describe a specific and independent method of massage therapy, utilizing the specific set of principles and techniques as defined by Riggs: “The understanding of the layers of the body, and the ability to work with tissue in these layers to relax, lengthen, and release holding patterns in the most effective and energy efficient way possible within the client's parameters of comfort”.Heterogeneity of techniques and protocols used in published studies have made it difficult to draw any clear conclusions. Favorable outcomes may result from deep tissue massage in pain populations and patients with decreased range of motion. In addition, several rare serious adverse events were found related to deep tissue massage, probably as a result of the forceful application of massage therapy.Conclusions
Future research of deep tissue massage should be based on a common definition, classification system and the use of common comparators as controls. 相似文献998.
999.
Reported normal values and weighted means for commonly used echocardiography pulsed Doppler and tissue Doppler measurements 下载免费PDF全文
Pulsed Doppler (PW) and tissue Doppler imaging (TDI) measurements are part of every echocardiography examination for evaluation of left ventricular (LV) diastolic function and filling pressure. The purpose of this study was to summarize published data on normal values for PW and TDI measurements. A PubMed search was performed on the 10th of October 2016 to identify relevant articles. Studies were considered relevant if they included more than 200 healthy individuals. A total of 13 studies were identified. Of these, 13 studies with 7777 subjects reported PW measurement over the mitral valve, six studies with 4082 subjects reported PW measurement in the pulmonary vein and 10 studies with 5988 subjects reported TDI. We also report weighted mean values for 14 different variables. As expected, measurements varied with age. There were no major differences between men and women. In contrast, there was a large difference in reported values between studies, in corresponding age groups. This review therefore raises caution about relying on normal values from just one study. 相似文献
1000.