BACKGROUND:Calcium phosphate has the similar mineral component of natural bones with good bioactivity, osteoconductivity and degradability. It has been widely used in bone defect repair and coatings of implants. OBJECTIVE:To review the major properties of different-phase calcium phosphate and to summarize the application of calcium phosphate in scaffolds for osteochondral tissue engineering. METHODS:A computer-based search of PubMed, CNKI and VIP database was performed for relevant articles published from January 2000 to February 2015 with the key words of “osteochondral; calcium phosphate (including hydroxyapatite, tricalcium phosphate, calcium polyphosphate); tissue engineering” in Chinese and English, respectively. RESULTS AND CONCLUSION:Since the calcium phosphate has a variety of phases and crystaline types, a variety of materials with different structure and size can be obtained using different techniques, such as hydroxyapatite, tricalcium phosphate, calcium polyphosphate, amorphous calcium phosphate. These materials have some differences in their biological and mechanical properties, and hydroxyapatite is the most widely used. Biocomposite scaffolds with calcium phosphates appeared to have promising potential in osteochondral tissue engineering.

BACKGROUND: Cell apoptosis is one of the important pathological changes in ischemic-reperfusion (IR) injury. As the key factor involved in cell apoptosis regulation, interleukin (IL)-iβ converting enzyme, when activated, leads to cell apoptosis via protein degradation.OBJECTIVE: To investigate the relationship between the expression of IL-1β converting enzyme and cell apoptosis in cerebral IR injury and explore the role of this enzyme in post-ischemia cell apoptosis.DESIGN: Randomized controlled experiment.MATERIALS: The experiment was performed at the Center of Neuroscience of the Third Military Medical University between March 1996 and December 2000. Totally 64 adult healthy Wistar rats were randomized into two groups, namely IR group (n=56) and sham operation group (n=8). In IR group, the rats were subjected to four vessel occlusion to mimic whole brain IR injury, and reperfusion was carried out after 30 minutes of ischemia for 3, 6, 12, 24, 48, 72 hours and 7 days, respectively (8 rats at each time point). Only separation but not occlusion of the bilateral common carotid artery was performed in sham operation group.METHODS: Four rats were randomly selected from IR group at each time point and 4 from the sham operation group for immunohistochemical study and in situ hybridization, with the other 4 rats for in situ end-labeling assay.MAIN OUTCOME MEASURES: Protein and mRNA expression of ILlβ converting enzyme and neural cell apoptosis in the brain.RESULTS: Totally 64 rats were used in this study and all data were statistically analyzed. In the sham operation group, IL-1β converting enzyme protein and mRNA were expressed in small amount in most of the normal brain tissues, and their expressions were also detected in the neurons and small glial cells in IR group localized mainly in the cerebral cortex, cerebellum Purkinje's cells, hippocampal and subcortical white matters. The expression of IL-lβ converting enzyme began to increase at IR 12 hours, reaching the peak level at 48-72 hours followed by declination since 7 days after the operation. Cell apoptosis occurred 12 hours after IR (49.4±6.8) /section and peaked at 72 hours (228.6±29.8)/section, showing significant correlation with the temporal expression of IL-1β converting enzyme protein and mRNA (r=0.89, 0.68, P ＜ 0.05).CONCLUSIONS: Expressions of IL-1β converting enzyme protein and mRNA increased after IR in close correlation with post-ischemia cell apoptosis, and their temporal expression pattern supports the presumption that IL-1β converting enzyme is an important factor in cell apoptosis.Apoptosis is mostly likely to occur in the cerebral cortex, hippocampus and basal ganglion in IR injury, where IL-1β converting enzyme is highly expressed, further demonstrating that post-ischemia expression of IL-1β converting enzyme might be involved in cell apoptosis regulation.

Objective: To investigate the current status and influencing factors of geriatric nursing competence of clinical nurses from grade A tertiary hospitals in Guangdong Province, and provide basic materials and evidence-based reference for the set of suitable allocation of geriatric nursing competence training plan. Methods: By convenience sampling, a total of 2 067 clinical nurses from 40 grade A tertiary hospitals in 16 prefecture-level cities in Guangdong Province were investigated with general information questionnaire and self-made geriatric nursing competence scale for clinical nurses. Results: The item average score was 2.30±0.71. Among three domains, professional literacy scored the highest, followed by professional practice and professional development. Among ten sub-domains, the top three scored were law and ethic, critical thinking and safe management while the bottom three were coaching and mentoring, professional learning, research and innovation. Multiple linear regression showed that the influencing factors of geriatric nursing competence were nursing age (B=0.011, 95%CI 0.006-0.015, P<0.01), professional title (B=0.031, 95%CI 0.002-0.066, P<0.05), interest in aged care (B=0.214, 95%CI0.179-0.250, P<0.01) and experience regarding geriatric specialized or professional nurses qualification training(B=0.250, 95%CI 0.152-0.349, P<0.01). Conclusions The geriatric nursing competence of clinical nurses from grade A tertiary hospital in Guangdong Province is in the middle level. Interventions to improve the professional development competence of clinical nurses is thus much needed. Hospital managers should establish the talent team according to geriatric nursing competence of clinical nurses, and take related training.