Incorporation of carboxymethyl chitosan (CMCS) for the modulation of physio-chemical characteristics and cell proliferation environment of the composite hydrogel microspheres.

Hydrogels have excellent swelling properties and have been widely applied in tissue engineering because of their similarity to the extracellular matrix (ECM). Sodium alginate (SA) and carboxymethyl chitosan (CMCS) were prepared into hydrogel microspheres with Ca2+crosslinking in our study. The morphology, inner structure, mechanical properties, water content, swelling rate and BMP-2 loading and releasing properties were characterized. Our results showed that the composite SA /CMCS hydrogel microspheres were translucent and spherical in shape with uniform particle size. The incorporation of CMCS further increased the diameters of the microspheres, internal pore structure, water content, and mechanical properties of the SA/CMCS hydrogel microspheres. At the same SA concentration, with the increase of CMSC concentration, the diameter of microspheres could be increased by about 0.4 mm, the water content can be increased about 1%-2%. As for the mechanical properties, the compressive strength can be increased by 0.04-0.1 MPa, and the modulus of elasticity can be increased by 0.1-0.15 MPa. BMP-2 was chosen as a model agent and it could be loaded into SA/CMCS microspheres, and the incorporation of CMCS increased BMP-2 loading. The encapsulated BMP-2 was sustainably releasedin vitro. The leaching solutions of the SA/CMCS hydrogel microspheres exhibited good cytocompatibility and could increase ALP activity, ALP expression, and biomineralization on MC3T3-E1 cells. After 7 d of co-culture, ALP activities in S2.5C2 and S2.5C3 groups was increased by 50% and 45% compared with that of the control group. When embedded in the SA/CMCS microspheres, the MC3T3-E1 cells were evenly distributed inside the hydrogel microspheres and remained viable. Transcriptomic studies showed that incorporation of CMCS induced upregulation of 1141 differentially expressed genes (DEGs) and downregulation of 1614 DEGs compared with SA microspheres. The most significantly enriched pathways were the Wnt and MAPK signaling pathways induced by the incorporation of CMCS and BMP-2. In conclusion, our results indicated that the physiochemical characteristics of the SA hydrogel microspheres could be greatly modulated by CMCS to better mimic the ECM microenvironment and induce osteo-inductive activities of MC3T3-E1 cells.

Fabrication of bioactive glass/phosphorylated chitosan composite scaffold and its effects on MC3T3-E1 cells.

This study aimed to synthesize bioactive glass (BG) and phosphorylated chitosan (PCS), and fabricate a BG/PCS composite scaffold. The physical properties (mechanical strength, swelling degree, and degradation rate) of the BG/PCS scaffold were tested. Thein vitromineralization properties of composite scaffolds in simulated body fluid were investigated. MC3T3-E1 cell responses with the BG/PCS scaffold were investigated using live/dead cell staining, actin staining, alkaline phosphatase (ALP) activity, and Alizarin red staining. Our results showed that the scaffold had an inner porous structure, good swelling properties, and good degradation rate. After immersion in SBF, the scaffolds demonstrated high properties in inducing mineralization. Leaching solutions of the composite scaffolds exhibited good cytocompatibility. MC3T3-E1 cells adhered, spread, and proliferated on the scaffold. The BG/PCS composite scaffold showed osteo-inductive activity by increasing ALP activity and calcium deposition. Our results indicated that the BG/PCS scaffold had potential applications as a bone-defect repair biomaterial.

Application of OB built-in tampon indwelled in anus and acupoint massage in ICU patients with incontinence / 现代临床护理

Objective To investigate the effects of OB built-in tampon indwelled in anus combined with acupoint massage in ICU patients with incontinence-associated dermatitis (IAD). Methods 100 patients with incontinence hospitalized in ICU were randomly assigned to control group (n=50) versus combined therapy group (n=50). The patients in the control group accepted routine nursing while the patients in the combined therapy group were treated with OB built-in tampon indwelled in anus combined with acupoint massage besides the routine nursing care. The two groups were compared in terms of incidence rate of IAD, IAD occurrence time, severity of IAD and incontinence-related nursing workload. Results The incidence rate of IAD and the severity of IAD in the combined therapy group were lower than those of the control group.The IAD in the combined therapy group occurred later than in the control group. Thetime for incontinence-related nursing and the frequency of perineum washing in the combined therapy group were shorter and lower than in the control group. Conclusions The application of OB built-in tampon indwelled in anus combined with acupoint massage in ICU patients with incontinence can not only reduce the incidence rate and severity of IAD but also lower the workload of nursing.The therapy is worthy of clinical application.

Perioperative nursing for patients undergoing mandibular defect repair by forearm flap composite fibula flap / 现代临床护理

Objective To summarize the perioperational nursing strategies for patients undergoing mandibular defect repair by forearm flap composite fibula flap.Methods From January 2009 to December 2012,9 patients with mandibular defect and soft tissue defects after resection of malignant tumors received fibula flap and forearm flap.Before operation,the patient received psychological education and the preparation of donor flap and receptor area together with oral preparation was performed.After operation,the vital signs and blood circulation in the flap were observed.Results The fibula and forearm flaps in 8 patients survived.The fibula flap in one patient survived while the forearm flap developed with vascular crisis.The success rate for the transplanted flap was 89.9%. Conclusion The perioperative nursing strategies are key to increase survival rate of flaps and the success rate of operation.