ABSTRACT
Dietary factors and nutritional status are closely related to the occurrence of cognitive impairment in the elderly. Excessive intake of nutrients such as lipids and carbohydrates in the diet is related to the occurrence of cognitive impairment. However, certain trace elements in the diet have a preventive effect on cognitive impairment. Based on the correlation analysis of dietary factors, nutritional status and cognitive impairment in the elderly, this paper expounds the relationship between cognitive impairment and its specific mechanism of action, in order to change the lifestyle of the elderly with cognitive impairment to improve their quality of life, and to provide a certain theoretical basis for the construction of dietary habits in line with national life.
ABSTRACT
BACKGROUND:The effects of engineered bone scaffold containing seeding cels with different shapes to repair bone defect are varied, while the loaded cellquantity is the important factor influencing the curative effect, but which is rarely reported. OBJECTIVE:By preparing self-made corrugated tissue-engineered bone scaffold and other three forms of bone tissue engineering scaffolds, to study the quantity of loaded cels on different scaffolds and osteogenesis of corrugated tissue-engineered bone scaffold so as to discuss the advantages and features of self-made corrugated tissue-engineered bone scaffold. METHODS: (1) Experimentin vitro: There were four kinds of scaffolds with the same volume and samples: calcium phosphate cement (CPC) corrugated surface scaffold group, smooth surface scaffold group, cylindrical scaffold group and porous cylindrical scaffold with holow tubes group, in which the latter three groups are control ones. A certain volume with same density of rabbit bone marrow mesenchymal stem cels (BMSCs) suspension after osteogenesis induction was seeded onto the scaffolds. After incubation, culture, digestion and colection, cellquantity was counted, absorbance value was finaly detected and cellactivity was proofed by alkaline phosphatase and alizarin red staining. (2) Experimentin vivo: New Zealand rabbits were randomly and equaly divided into recombinant human bone morphogenetic protein-2 (rhBMP-2)/CPC/BMSCs corrugated scaffold group, pure CPC corrugated scaffold group and cancelous bone implant group. Three kinds of scaffold implants with the same volume were inserted into the area between rabbit’s L5, 6 transverse processes bilateraly. At 4, 8, 12 weeks postoperatively, gross and histological observation was performed. RESULTS AND CONCLUSION:(1)Experimentin vitro: The drip of cellsuspension steadily stayed on the surface of corrugated scaffold because of corrugated shape groove and the surface tension of the liquid. The amount of cels per sample digested down from the CPC corrugated surface scaffold was significantly more than that from the other three groups (P 0.05). (2) Experimentin vivo: At each time point the osteogenesis quantity of rhBMP-2/CPC/BMSCs corrugated scaffold group was more than that of the pure CPC corrugated scaffold group (P 0.05). These findings indicate that the characteristics of the self-made corrugated engineered bone scaffold are beneficial to seed cellloading, which supports a large number of osteogenesis and provides feasibility to promote the healing of segmental bone defects.