Preparation and characterization of oriented scaffolds derived from cartilage extracellular matrix and silk fibroin / 华西口腔医学杂志

OBJECTIVE@#This study aims to prepare oriented scaffolds derived from a cartilage extracellular matrix (CECM) and silk fibroin (SF) and use to investigate their physicochemical property in cartilage tissue engineering.@*METHODS@#Oriented SF-CECM scaffolds were prepared from 6% mixed slurry (CECM：SF=1：1) through modified temperature gradient-guided thermal-induced phase separation, followed by freeze drying. The SF-CECM scaffolds were evaluated by scanning electron microscopy (SEM) and histological staining analyses and determination of porosity, water absorption, and compressive elastic modulus of the materials.@*RESULTS@#The SEM image showed that the SF-CECM scaffolds contained homogeneous reticular porous structures in the cross-section and vertical tubular structures in the longitudinal sections. Histological staining showed that cells were completely removed, and the hybrid scaffolds retained proteogly can and collagen. The composition of the scaffold was similar to that of natural cartilage. The porosity, water absorption rate, and vertical compressive elastic modulus of the scaffolds were 95.733%±1.010%, 94.309%±1.302%, and (65.40±4.09) kPa, respectively.@*CONCLUSIONS@#The fabricated SF-CECM scaffolds exhibit satisfactory physicochemical and biomechanical properties and thus could be an ideal scaffold in cartilage tissue engineering.

Time-series Analysis in Imatinib-resistant Chronic Myeloid Leukemia K562-cells under Different Drug Treatments / 华中科技大学学报（医学）（英德文版）

Chronic myeloid leukemia (CML) is characterized by the accumulation of active BCR-ABL protein.Imatinib is the first-line treatment of CML;however,many patients are resistant to this drug.In this study,we aimed to compare the differences in expression patterns and functions of time-series genes in imatinib-resistant CML cells under different drug treatments.GSE24946 was downloaded from the GEO database,which included 17 samples of K562-r cells with (n=12) or without drug administration (n=5).Three drug treatment groups were considered for this study:arsenic trioxide (ATO),AMN107,and ATO+AMN107.Each group had one sample at each time point (3,12,24,and 48 h).Time-series genes with a ratio of standard deviation/average (coefficient of variation) ＞0.15 were screened,and their expression patterns were revealed based on Short Time-series Expression Miner (STEM).Then,the functional enrichment analysis of time-series genes in each group was performed using DAVID,and the genes enriched in the top ten functional categories were extracted to detect their expression patterns.Different time-series genes were identified in the three groups,and most of them were enriched in the ribosome and oxidative phosphorylation pathways.Time-series genes in the three treatment groups had different expression patterns and functions.Time-series genes in the ATO group (e.g.CCNA2 and DAB2)were significantly associated with cell adhesion,those in the AMN107 group were related to cellular carbohydrate metabolic process,while those in the ATO+AMN107 group (e.g.AP2M1) were significantly related to cell proliferation and antigen processing.In imatinib-resistant CML cells,ATO could influence genes related to cell adhesion,AMN107 might affect genes involved in cellular carbohydrate metabolism,and the combination therapy might regulate genes involved in cell proliferation.