ObjectiveTo review the development of cell sheet engineering technology in engineering vascularized tissue. MethodsThe literature about cell sheet engineering technology and engineering vascularized tissue was reviewed, analyzed, and summarized. ResultsAlthough there are many methods to engineer vascularized tissue, cell sheet engineering technology provides a promising potential to develop a vascularized tissue. Recently, cell sheet engineering technology has become a hot topic in engineering vascularized tissue. Co-culturing endothelial cells on a cell sheet, endothelial cells are able to form three-dimensional prevascularized networks and microvascular cavities in the cell sheet, which facilitate the formation of functional vascular networks in the transplanted tissue. ConclusionCell sheet engineering technology is a promising strategy to engineer vascularized tissue, which is still being studied to explore more potential.
ObjectiveTo systematically evaluate the association between MTHFR gene C677T polymorphism and susceptibility to young and middle-aged adult ischemic stroke among Chinese population. MethodsSuch databases as PubMed, EMbase, The Cochrane Library (Issue 11, 2013), CBM, CNKI, VIP and WanFang Data were systemically searched to collect case-control studies published from Jan 1990 to Dec 2013. RevMan 5.2 was used to quantitatively analyzed the qualified and included studies, the pooled odds ratio (ORs) with 95% confidence interval (CI) were calculated; Stata 12.0 software were used for sensitivity and publication bias analysis. ResultsA total of 10 studies were included, which involved 787 cases and 766 controls. The results of meta-analysis showed that, in overall young and middle-aged adult group (aged less than 60), individuals that carried T allele risked more with ischemic stroke than those carried C allele (OR=1.42, 95%CI 1.07 to 1.89, P=0.02); more susceptibility to ischemic stroke was found among people of TT genotype compared with those of CC genotype (OR=2.11, 95%CI 1.58 to 2.81, P=0.00), as well as those of TT+TC genotype compared with CC genotype (OR=1.97, 95%CI 1.55 to 2.51, P=0.00), and those of TT genotype compared with TC+CC genotype (OR=1.42, 95%CI 1.13 to 1.77, P=0.00). Increased risk was also observed in TT+TC genotype compared with CC genotype in young adult subgroup (aged less than 45) (OR=1.66, 95%CI 1.19 to 2.32, P=0.00). ConclusionMTHFR gene C677T polymorphism is significantly associated with susceptibility to young and middle-aged adult ischemic stroke among Chinese population, and more risk may exist in middle-aged adult population.
ObjectiveTo evaluate the effectiveness of very low profile/variable angle locking plate (VLP) internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach. MethodsA retrospective analysis was made on the clinical data from 13 patients with posterior Pilon fractures extending to the medial malleolus between December 2011 and August 2012. There were 4 males and 9 females with an average age of 48.9 years (range, 23-68 years). Fractures were caused by falling in 9 cases and by traffic accident in 4 cases. The locations were the left ankle in 6 cases and the right ankle in 7 cases. According to the Orthopedic Trauma Association (OTA) classification, 6 cases were rated as type 43B1, 4 cases as type 43B2, and 3 cases as type 43B3. Twelve cases had fibular fractures, including 11 cases of Denis-Weber type B, 1 case of Denis-Weber type C. The interval of injury and operation was 7-14 days (mean, 11.4 days). Open reduction was performed and VLP internal fixation was used for posterior malleolar fracture by posteromedial approach. ResultsPrimary healing of incision was obtained in all patients. Tibial nerve palsy was observed in 2 cases, and was cured after oral administration of mecobalamin. Twelve cases were followed up 12-18 months (mean, 14.5 months). According to the Burwell-Charnley's radiological evaluation system, 11 cases achieved anatomical reduction, 1 case achieved fair reduction. The fracture union time was 3-6 months (mean, 3.7 months). No loosening or breakage of internal fixation occurred during follow-up. According to the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, the results were excellent in 7 cases, good in 4, and fair in 1; the excellent and good rate was 91.7%. ConclusionVLP internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach can achieve good short-term effectiveness. The high quality of reduction is acquired under direct vision with low rate of soft tissue complications.
In order to solve the problem of high cytotoxicity in vitro of nano-silver antibacterial gel, and the problem of large nano-silver particle size and size distribution, this study prepared nano-silver antibacterial gel with better biocompatibility and good antibacterial effect by using physical cross-linking method and using poloxamer as dispersant when prepared nano-silver. In this study, nano-silver was prepared by photo-initiator method and by adding poloxamer as a dispersant, and then UV-visible absorption spectrum test and scanning electron microscopy (SEM) test were carried out using prepared nano-silver mixture and particles after drying respectively. The gel was prepared through adjusting its pH value by using sodium bicarbonate, and then pH value test, SEM test for cross-section of gel, swelling ratio test, viscosity test, inhibition zone test and in vitro cytotoxicity test were carried out. The test results showed that the maximum absorption wavelength of prepared nano-silver, using poloxamer as dispersant and ultra-pure water as solvent, was 414 nm, and the average nano-silver size was about 60 nm. The prepared nano-silver using poloxamer as dispersant had smaller particle diameter and narrower particle size distribution than those using PVP as dispersant. Similarly, the prepared nano-silver using ultra-pure water as solvent also had smaller particle diameter and narrower particle size distribution than those using distilled water as solvent. The pH value of the prepared gel was between 5.8~6.1. The dried gel section had many holes. The water absorption of gel was fine and the viscosity of gel was fit to coat on the gauze. In addition, the prepared gel with nano-silver had greater ability to inhibit Escherichia coli and Staphyloccocus aureus at the concentrations of 24, 18 and 12 μg/mL. And the biocompatibility of the prepared gel with nano-silver was good when the concentration below 24 μg/mL. Based on the above features, the nano-silver antibacterial gel could be used in the treatment of burn or other wounds.
ObjectiveTo comprehend the incidence of and to search for the possible risk factors for neonatal congenital heart disease (CHD) in Mianyang after "5·12" Earthquake. MethodsCHD screening was performed on 5536 neonates born between December 2011 and December 2012 by cardiac auscultation, respiration evaluation, blood oxygen saturation determination and color doppler flow imaging. Case control study was applied to study the diagnosed cases of CHD. ResultsSixty-five cases of CHD were found during the screening, and the incidence was 11.74‰. The most common CHD was ventricular septal defect, followed by atrial septum defect and patent ductusarteriosus. Possible risk factors were listed in order of their risks were as follows:family history of CHD, infection history in the early period of pregnancy, drug and alcohol history during pregnancy, and aged pregnancy and smoking history of the parents. However, earthquake experience history of parents was not correlated with CHD incidence. ConclusionEarthquake experience of parents is not correlated with CHD incidence. Enforcing health education for women before gestation, and avoiding or decreasing risk factors exposure can reduce the risk of CHD. CHD screening for neonates can detect CHD as early as possible, which is helpful for intervention during the follow-up, reduction of fatality, and improvement of neonates' quality of life.