Highly expanded nanocomposite foams of polypropylene and carbon nanotubes (PP/CNT) are formed using supercritical carbon dioxide (scCO2) technology. The foaming parameters (temperature, pressure) are investigated to establish their influence on the morphology of the resulting foams and their impact on the electrical conductivity. As promising electromagnetic‐interference (EMI) absorbers, the EMI shielding performance of the foams is determined, and a preliminary relationship is established between foam morphology and the EMI shielding performance. The best candidates are highly expanded foams with a volume expansion of >25, containing 0.1 vol% CNTs; they are able to absorb more than 90% of the incident radiation between 25 and 40 GHz.
The use of stem cell‐derived sheets has become increasingly common in a wide variety of biomedical applications. Although substantial evidence has demonstrated that human platelet lysate (PL) can be used for therapeutic cell expansion, either as a substitute for or as a supplement to xenogeneic fetal bovine serum (FBS), its impact on cell sheet production remains largely unexplored. In this study, we manufactured periodontal ligament stem cell (PDLSC) sheets in vitro by incubating PDLSCs in sheet‐induction media supplemented with various ratios of PL and FBS, i.e. 10% PL without FBS, 7.5% PL + 2.5% FBS, 5% PL + 5% FBS, 2.5% PL + 7.5% FBS or 10% FBS without PL. Cultures with the addition of all the designed supplements led to successful cell sheet production. In addition, all the resultant cellular materials exhibited similar expression profiles of matrix‐related genes and proteins, such as collagen I, fibronectin and integrin β1. Interestingly, the cell components within sheets generated by media containing both PL and FBS exhibited improved osteogenic potential. Following in vivo transplantation, all sheets supported significant new bone formation. Our data suggest that robust PDLSC sheets can be produced by applying PL as either an alternative or an adjuvant to FBS. Further examination of the relevant influences of human PL that benefit cell behaviour and matrix production will pave the way towards optimized and standardized conditions for cell sheet production. 相似文献
OBJECTIVE: At present, there are few materials available for esophagus reconstruction anywhere in the world. The reported survival rate in animals during the perioperative period is comparatively low. The present study assessed the feasibility of using a biotype artificial esophagus in the reconstruction of a dog's esophagus. METHODS: In 30 mongrel dogs, a portion of the thoracic esophagus was resected and an 8 cm section of artificial esophagus was transplanted to reconstruct the organ. The survival rate, food intake and process of healing were observed. RESULTS: Of the 30 dogs, 28 survived the perioperative period (93.3% survival). Two dogs (6.7%) developed an anastomotic fistula; 19 dogs survived for 1 year, a survival rate of 79.2% (19/24) with the remaining six dogs were killed according to the experimental protocol. Detachment of the artificial esophagus occurred on average 28.8 days after operation and the dogs suffered from varying degrees of dysphagia 23?45 days after operation. Gradual remission occurred after 4 months. The histological study revealed that the regenerated esophagus was composed of fibrous and connective tissues and the luminal surface was covered with squamous epithelium in 3?6 months. CONCLUSION: The transplanted artificial esophagus detached after the surrounding ‘regenerated esophagus’ had formed, and the squamous epithelium gradually covered the luminal surface. Continuous remodeling of the ‘regenerated esophagus’ gradually relieved the stenosis. Whether detachment of the implant and the postoperative stenosis can be solved is the key problem restricting the use of the biotype artificial esophagus in clinical practice. 相似文献
Acetaminophen (APAP)-induced hepatotoxicity comes among the most frequent humans’ toxicities caused by drugs. So far, therapeutic interventions for such type of drug-induced toxicity are still limited. In the current study, we examined the influence of capmatinib (Cap), a novel c-Met inhibitor, on APAP-induced hepatotoxicity in mice when administered 2 h prior, 2 h post and 4 h post APAP-challenge. The results revealed that Cap administration significantly attenuated APAP-induced liver injury when administered only 2 h prior and post APAP-administration. Cap hepatoprotective effect was mediated by lowering the excessive formation of lipid peroxidation and nitrosative stress products caused by APAP. Besides, Cap attenuated APAP-induced overproduction and release of proinflammatory mediators like TNF-α, IL-1β, IL-17A, IL-6, and MCP-1. Cap treatment also led to avoidance of APAP-subsequent repair by abating APAP-induced elevation of hepatic IL-22 and PCNA expressions. In conclusion, c-Met receptor inhibition may be a potential strategy for alleviating APAP-hepatotoxicity, especially when administered in the early phase of intoxication. 相似文献