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In order to improve the surface quality of zirconia ceramic workpieces, the magnetic compound fluid polishing tool were utilized. This was done to lessen the material's surface roughness, minimize surface and subsurface damage. With a focus on the effects of magnet speed, processing gap, and abrasive particle size in the polishing fluid on surface roughness and material removal rate, a 3-factor, 3-level orthogonal test was created using Taguchi's method. The weights of each factor on the two evaluation indices were then analyzed using ANOVA. The best process parameter combination for surface roughness was 300 r/min for the magnet speed, 0.5 mm for the processing gap, and 1.25 µm for the abrasive particle size; the best process parameter combination for material removal rate was 400 r/min for the magnet speed, 0.5 mm for the processing gap, and 2 µm for the abrasive particle size. With these processing parameters, the surface roughness can reach up to 4.5 nm, and the material removal rate can reach up to 0.117 µm/min. The optimization effect is significant. The polishing prediction model was developed using a BP neural network that has been genetic algorithm optimized. The prediction error was 3.948 4%. [ABSTRACT FROM AUTHOR]

Background: Cow's milk protein allergy (CMPA) is commonly seen in children. There have been no reports of the true prevalence of CMPA in Chinese infants. The aim of this population-based study is to determine the prevalence, clinical characteristics, and outcome of CMPA in Chinese infants.Methods: We carried out a prospective survey in 7 participating hospitals throughout southern China. We included infants ≤12 months of age during the survey. For those suspected of CMPA, oral food challenge with cow's milk protein (CMP) was performed. A follow-up telephone interview was conducted at 12 months after the diagnosis to assess the clinical outcome of CMPA.Results: A total of 9910 questionnaire surveys were distributed and 7364 (74.3%) were returned. The eligible survey number of surveys was 6768 (91.9%). A total of 182 infants was confirmed with CMPA, including 13 with anaphylactic reactions, 28 with clinical symptoms and serum immunoglobulin E (sIgE) >3.5 IU/mL, and 141 with positive CMP challenge test. The prevalence of CMPA was 2.69%. Infants with confirmed CMPA had significantly stronger family history of either 1 or both parents with food allergy, higher Cesarean section rate, and lower rate of breastfeeding, compared with those without CMPA. At 12-month telephone follow-up of 176 CMPA infants, 136 infants (77.3%) had become tolerant to CMP.Conclusions: The prevalence of CMPA was 2.69%. CMPA infants had a strong family history of food allergy and atopy. Both Cesarean delivery and formula feeding were risk factors for CMPA. At 12-month follow-up, the majority of CMPA infants had become tolerant to CMP. [ABSTRACT FROM AUTHOR]

Autologous fat transplantation is increasingly applied in plastic and reconstructive surgery. Stromal vascular fraction cells (SVFs) combined with angiogenic factors, such as VEGF (vascular endothelial growth factor A) and Ang‐1 (angiogenin‐1), can improve angiogenesis, which is a critical factor for graft survival. However, direct transplant with such a mixture is insufficient owing to the short half‐life of angiogenic factors. In this study, we evaluated whether a double sustained release system of VEGF/ANG‐1‐PLGA (poly (lactic‐co‐glycolic acid)) microspheres plus SVFs can improve angiogenesis and graft survival after autologous fat transplantation. VEGF/ANG‐1‐PLGA‐sustained release microspheres were fabricated by a modified double emulsion–solvent evaporation technique. Human aspirated fat was mixed with SVF suspension plus VEGF/ANG‐1 sustained release microspheres (Group C), SVF suspension (Group B) alone, or Dulbecco's modified Eagle's medium as the control (Group A). Eighteen immunocompromised nude mice were injected with these three mixtures subcutaneously at random positions. After 8 weeks, the mean volume of grafts was greater in the SVFs plus VEGF/ANG‐1‐PLGA group than in the control and SVFs groups (1.08 ± 0.069 ml vs. 0.62 ± 0.036 ml, and 0.83 ± 0.059 ml, respectively). Histological assessments showed that lower fibrosis, but greater microvascular density in the SVFs plus VEGF/ANG‐1‐PLGA group than in the other groups, though the SVFs group also had an appropriate capillary density and reduced fibrosis. Our findings indicate that SVFs plus VEGF/ANG‐1‐PLGA‐sustained release microspheres can improve angiogenesis and graft survival after autologous fat transplantation. Our study demonstrates that stromal vascular fraction cells combined with dual sustained release VEGF/ANG‐1‐PLGA microspheres can improve angiogenesis and graft survival. Nude mice treated with stromal vascular fraction cells and the microspheres developed in this study exhibited reduced fibrosis and increased microvascular density. These findings provide a practical method for improving graft survival after autologous fat transplantation. [ABSTRACT FROM AUTHOR]

Background: Adipose-derived stem cells have attracted significant interest, especially in stem cell therapy and regenerative medicine. However, these cells undergo gradual premature senescence in long-term cultures, which are essential for clinical applications that require cell-assisted lipotransfer or tissue repair. Methods: Since the extracellular matrix forms the microenvironment around stem cells in vitro and regulates self-renewal and multipotency in part by slowing down stem cell aging, we evaluated its potential to protect against senescence, using H 2 O 2 -induced adipose-derived stem cells as a model. Results: We found that supplementing cultures with decellularized extracellular matrix harvested from the same cells significantly promotes proliferation and reverses signs of senescence, including decreased multipotency, increased expression of senescence-associated β-galactosidase, and accumulation of reactive oxygen species. Conclusion: These findings suggest a novel approach in which an autologous decellularized extracellular matrix is used to prevent cellular senescence to enable the use of adipose-derived stem cells in regenerative medicine., (© 2019 The Author(s).)

Objective: To review the research progress of growth factor sustained-release microspheres in fat transplantation., Methods: The recently published 1iterature at home and abroad related the growth factor sustained-release microspheres in fat transplantation was reviewed and analyzed., Results: The sustained-release microsphere carrier materials include natural polymer materials and synthetic polymer materials.The sustained-release complexes of different microsphere materials with different growth factors can promote the vascularization of transplanted fat in a timely manner, improve the survival rate of grafts, and reduce the incidence of complications such as liquefaction, calcification, and necrosis., Conclusion: The growth factor sustained-release microspheres have the characteristics of persistence and controllability, which is a research hotspot in the field of fat transplantation and has broad application prospects.