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991.
Schwann cells are promising candidates for transplantation strategies in the central nervous system by promoting axonal regeneration. The dog represents a translational model for human spinal cord injury (SCI) for studies with new repair strategies after intervertebral disk herniation (IVDH). To overcome the necessity for an additional surgical procedure, for the first time a protocol for the isolation and purification of canine Schwann cells from spinal nerve biopsies during standard hemilaminectomy in IVDH‐affected paraplegic dogs for potential transplantation has been developed. Purity was assessed by flow cytometry. The results were compared with biopsies from dogs without SCI. Within 26 ± 4 days, 90.2 ± 8.8% p75 neurotrophin receptor (p75NTR)‐positive cells were achieved in IVDH dogs. The total cell count in acute/subacute and chronic IVDH (acute/subacute: 6.82 ± 6.36 × 106; chronic: 2.29 ± 2.00 × 106) differed significantly (p = 0.0120) at the potential time point of transplantation. No differences in culture period and purity were detected between dogs with and without IVDH. Despite the small sample size and the altered environment, the isolation of Schwann cells was successful. Negative influences on isolation and purification due to potential pathological changes at the biopsy site of IVDH‐diseased dogs were ruled out by comparison of Schwann cell pellets from diseased and control dogs. Finally, the functionality of Schwann cells from dogs with IVDH was outlined in co‐culture experiments with canine dorsal root ganglion neurons. In conclusion, nerve root biopsies provide a sufficient number of highly purified and functional Schwann cells within a useful time period for novel therapeutic strategies in dogs with SCI.  相似文献   
992.
993.
Autologous fat grafting is a common procedure for soft‐tissue reconstruction but is associated with a graft resorption rate ranging from 20% to 80%. To improve the fat graft survival rate, a new technique, called cell‐assisted lipotransfer (CAL), was developed. With CAL, fat is injected along with adipose‐derived stromal cells that are assumed to improve fat survival rate. We conducted an evidence‐based meta‐analysis to evaluate the efficacy and safety of CAL as compared with conventional autologous fat grafting (non‐CAL). The databases MEDLINE (via PubMed), Cochrane Library, EBSCO, Web of Science, and EMBASE were searched for reports of clinical trials, case series, and cohorts available from 2008 to 2016. We conducted a meta‐analysis of the efficacy of CAL with data analysis concerning fat survival rate. The incidence of complications and the need for multiple procedures were evaluated to determine the safety of CAL. We identified 25 studies (696 patients) that were included in the systematic review; 16 studies were included in the meta‐analysis to evaluate the efficacy of CAL. The fat survival rate was significantly higher with CAL than non‐CAL (64% vs. 44%, p < .0001) independent of injection site (breast and face). This benefit of CAL was significant for only injection volumes <100 ml (p = .03). The two groups did not differ in frequency of multiple procedures after fat grafting, but the incidence of complications was greater with CAL than non‐CAL (8.4% vs. 1.5%, p = .0019). The CAL method is associated with better fat survival rate than with conventional fat grafting but only for small volumes of fat grafting (<100 ml). Nonetheless, the new technique is associated with more complications and did not reduce the number of surgical procedures needed after the first fat grafting. More prospective studies are required to draw clinical conclusions and to demonstrate the real benefit of CAL as compared with common autologous fat grafting.  相似文献   
994.
Cardiac‐derived adherent proliferating (CardAP) cells obtained from endomyocardial biopsies (EMBs) with known anti‐fibrotic and pro‐angiogenic properties are good candidates for the autologous therapy of end‐stage cardiac diseases such as dilated cardiomyopathy. However, due to the limited number of CardAP cells that can be obtained from EMBs, our aim is to isolate cells with similar properties from other regions of the heart with comparable tissue architecture. Here, we introduce the atrial appendage as a candidate region. Atrial appendage‐derived cells were sorted with CD90 microbeads to obtain a CD90low cell population, which were subsequently analysed for their surface marker and gene expression profiles via flow cytometry and micro array analysis. Enzyme‐linked immunosorbent assays for vascular endothelial growth factor and interleukin‐8 as well as tube formation assays were performed to investigate pro‐angiogenic properties. Furthermore, growth kinetic assays were performed to estimate the cell numbers needed for cell‐based products. Microarray analysis revealed the expression of numerous pro‐angiogenic genes and strong similarities to CardAP cells with which they also share expression levels of defined surface antigens, that is, CD29+, CD44+, CD45?, CD73+, CD90low, CD105+, and CD166+. High secretion levels of vascular endothelial growth factor and interleukin‐8 as well as improved properties of vascular structures in vitro could be detected. Based on growth parameters, cell dosages for the treatment of more than 250 patients are possible using one appendage. These results lead to the conclusion that isolating cells with regenerative characteristics from atrial appendages is feasible and permits further investigations towards allogenic cell‐based therapies.  相似文献   
995.
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   
996.
Recently, computer‐designed three‐dimensional (3D) printing techniques have emerged as an active research area with almost unlimited possibilities. In this study, we used a computer‐designed 3D scaffold to drive new bone formation in a bone defect. Poly‐L‐lactide (PLLA) and bioactive β‐tricalcium phosphate (TCP) were simply mixed to prepare ink. PLLA + TCP showed good printability from the micronozzle and solidification within few seconds, indicating that it was indeed printable ink for layer‐by‐layer printing. In the images, TCP on the surface of (and/or inside) PLLA in the printed PLLA + TCP scaffold looked dispersed. MG‐63 cells (human osteoblastoma) adhered to and proliferated well on the printed PLLA + TCP scaffold. To assess new bone formation in vivo, the printed PLLA + TCP scaffold was implanted into a full‐thickness cranial bone defect in rats. The new bone formation was monitored by microcomputed tomography and histological analysis of the in vivo PLLA + TCP scaffold with or without MG‐63 cells. The bone defect was gradually spontaneously replaced with new bone tissues when we used both bioactive TCP and MG‐63 cells in the PLLA scaffold. Bone formation driven by the PLLA + TCP30 scaffold with MG‐63 cells was significantly greater than that in other experimental groups. Furthermore, the PLLA + TCP scaffold gradually degraded and matched well the extent of the gradual new bone formation on microcomputed tomography. In conclusion, the printed PLLA + TCP scaffold effectively supports new bone formation in a cranial bone defect.  相似文献   
997.

Aims

To examine specific self‐care behaviours, depression, and diabetes‐related stress among South Korean patients with type 2 diabetes and to evaluate whether these factors are related to glycaemic control.

Methods

This cross‐sectional study included 171 patients with type 2 diabetes who visited an endocrinology clinic. A structured questionnaire and electronic medical records were used to collect data regarding self‐care behaviours, depression, diabetes‐related distress, and glycaemic control between May 2015 and July 2015.

Results

Compared with the group with good glycaemic control, the group with poor glycaemic control had significantly lower values for medication adherence and significantly greater values for regimen‐related distress. Depression was not significantly associated with glycaemic control. In logistic regression analysis, only medication adherence was independently associated with glycaemic control.

Conclusions

Medication adherence should be continuously emphasized and monitored in clinical practice to effectively manage glycaemic control among patients with type 2 diabetes. Furthermore, consideration of diabetes‐related distress may help improve glycaemic control among patients with type 2 diabetes.  相似文献   
998.
999.
1000.
In recent years, a person‐centred approach to patient care in cases of mental illness has been promoted as an alternative to a disease orientated approach. Alexandra Parvan's contribution to the person‐centred approach serves to motivate an exploration of the approach's most apt metaphysical assumptions. I argue that a metaphysical thesis or assumption about both persons and their uniqueness is an essential element of being person‐centred. I apply the assumption to issues such as the disorder/disease distinction and to the continuity of mental health and illness.  相似文献   
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