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Influenza vaccines, which are recommended by the World Health Organization (WHO), are the most effective preventive measure against influenza virus infection. Madin–Darby canine kidney (MDCK) cell culture is an emerging technology used to produce influenza vaccines. One challenge when purifying influenza vaccines using this cell culture system is to efficiently remove impurities, especially host cell double-stranded DNA (dsDNA) and host cell proteins (HCPs), for safety assurance. In this study, we optimized ion-exchange chromatography methods to harvest influenza viruses from an MDCK cell culture broth, the first step in influenza vaccine purification. Bind/elute was chosen as the mode of operation for simplicity. The anion-exchange Q chromatography method was able to efficiently remove dsDNA and HCPs, but the recovery rate for influenza viruses was low. However, the cation-exchange SP process was able to simultaneously achieve high dsDNA and HCP removal and high influenza virus recovery. For the SP process to work, the clarified cell culture broth needed to be diluted to reduce its ionic strength, and the optimal dilution rate was determined to be 1:2 with purified water. The SP process yielded a virus recovery rate exceeding 90%, as measured using a hemagglutination units (HAUs) assay, with removal efficiencies over 97% for HCPs and over 99% for dsDNA. Furthermore, the general applicability of the SP chromatography method was demonstrated with seven strains of influenza viruses recommended for seasonal influenza vaccine production, including H1N1, H3N2, B (Victoria), and B (Yamagata) strains, indicating that the SP process could be utilized as a platform process. The SP process developed in this study showed four advantages: (1) simple operation, (2) a high recovery rate for influenza viruses, (3) a high removal rate for major impurities, and (4) general applicability. [ABSTRACT FROM AUTHOR]

Stimulus‐responsive large‐scale cell culture microcarriers are promising biological materials for large‐scale cell production. Herein, multifunctional thermal and magnetic microcarriers (TMMs) made of poly(N‐isopropylacrylamide) (PNIPAM), polylysines (PLLs), gelatin methacryloyl (GelMA), poly(ethylene glycol) diacrylate (PEGDA), N,N‐methylenebis(acrylamide) (MBA), Fe3O4 and SiO2 are prepared to achieve large‐scale enzyme‐free cell harvesting and also can be used as cells stereogrowth scaffold to mimic cells suspension state to develop novel application, such as recombinant proteins produced. In TMMs, NIPAM and other materials are mixed and then underwent in situ radical polymerization by UV irradition with 2‐hydroxy‐2‐methylpropiophenone as initiator, in which GelMA provides cell adhesion sites and PLLs enable a positive microenvironment with SiO2 as filler. As enzyme‐free cell microcarriers, cell harvesting from TMMs by PNIPAM are achieved at 25 °C through vortex oscillation within 15 min and TMMs can be recycled at least for four times by magnetic recovery. Moreover, TMMs can be used as stereoculture scaffold to let cells in suspension as adherent state to improve gene transfection efficiency. Combined with magnetothermal effect, TMMs can further improve gene transfer to obtain industrialization of proteins expression. Therefore, TMMs are potential for the development of cell manufacturing and the expansion of cell stereogrowth application for recombinant proteins production. [ABSTRACT FROM AUTHOR]

A singular resonance is discovered in investigating the features of high-frequency photoacoustic (PA) effect with multilayers. Theoretical analysis of its formation is carried out and reveals that it is a result of interaction between the resonance of gas-heat and that of solid-heat, while they happen simultaneously and fight for vibrational energy at some higher frequencies. This finding presents a new gas-solid-heat coupling phenomenon with dual resonance and may be of significance for recognizing of high-frequency PA effect and characterizing of micro/nano films. [ABSTRACT FROM AUTHOR]

Background: Chemoresistance is a major obstacle to improving the survival rate of colorectal cancer (CRC) patients. Forkhead box protein C2 (FOXC2), a member of the forkhead box (Fox) transcription factor family, is reported to be an important regulator of epithelial-to-mesenchymal transition (EMT) and plays a key role in tumor progression. However, little is known about the effects of FOXC2 on oxaliplatin (OXA) resistance in CRC. Methods: OXA-resistant cells were generated from HCT116 cells. CCK-8, colony formation, flow cytometry and Transwell assays were used to compare the characteristics of OXA-resistant HCT116/OXA cells and the corresponding parental HCT116 cells. The expression of FOXC2 was confirmed by qRT-PCR and Western blotting in HCT116/OXA and HCT116 cells. Gain- and loss-of-function assays were performed to evaluate the effects of FOXC2 on OXA sensitivity and EMT in HCT116/OXA and HCT116 cells both in vitro and in vivo, and the possible molecular mechanisms were investigated. Results: The relative expression of FOXC2 was significantly increased in HCT116/OXA cells compared with the parental HCT116 cells. Upregulation of FOXC2 in HCT116 cells reduced OXA sensitivity and promoted EMT. However, knockdown of FOXC2 in HCT116/OXA cells markedly increased the in vitro and in vivo sensitivity of HCT116/OXA cells to OXA by regulating EMT progression. Furthermore, FOXC2 activated MAPK/ERK signaling, and blockade of ERK attenuated FOXC2-induced EMT and FOXC2-enhanced OXA resistance. Conclusion: FOXC2 induced EMT to promote oxaliplatin resistance by activating the MAPK/ERK signaling pathway. FOXC2 may be a potential therapeutic target for overcoming OXA resistance in human CRC. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is a common human malignancy. The aims of this study are to investigate the gene expression profile of CRC and to explore potential strategy for CRC diagnosis, therapy and prognosis. Methods: We use affy and Limma package of Bioconductor R to do differential expression genes (DEGs) and differential expression lncRNAs (DELs) analysis from the gene datasets (GSE8671, GSE21510, GSE32323, GSE39582 and TCGA) respectively. Then, DEGs were analyzed by GO and KEGG pathway and Kaplan-Meier survival curve and Cox regression analyses were used to find aberrantly expressed genes associated with survival outcome of CRC patients. Real-time PCR assay was used to verify the aberrantly expressed genes expression in CRC samples. Results: 306 up-regulation and 213 down-regulation common DEGs were found. A total of 485 DELs were identified, of which 241 up-regulated and 244 down-regulated. Then, GO and KEGG pathway analyses showed that DEGs were involved in cell cycle, mineral absorption, DNA replication, and Nitrogen metabolism. Among them, Kaplan-Meier survival curve and Cox regression analyses revealed that CDC6, CDC45, ORC6 and SNHG7 levels were significantly associated with survival outcome of CRC patients. Finally, real-time PCR assay was used to verify that the CDC6, CDC45, ORC6 and SNHG7 expression were up-regulated in 198 CRC samples compared with the expression levels in individual-matched adjacent mucosa samples. Conclusion: CDC6, CDC45, ORC6 and SNHG7 are implicated in CRC initiation and progression and could be explored as potential diagnosis, therapy and prognosis targets for CRC. [ABSTRACT FROM AUTHOR]

Background: A tibia shaft fracture is one of the most common long bone fractures, with two general types, open fracture and close fracture. However, there is no universally accepted guideline suggesting which treatment to use under certain circumstances. Therefore, a comprehensive network meta-analysis (NMA) is needed to summarize existing studies and to provide more credible data-based medical guidelines. Methods: Available literature was identified by searching medical databases with relevant key terms. Studies that met the inclusion and exclusion criteria, baseline, intervention, and the outcome of treatments, were extracted. A comparative connection of these studies was demonstrated through net plots. Continuous variables and binary variables were reported as mean difference (MD) and odds ratio (OR) with a 95% credible interval (CrI), respectively. The comparison of direct and indirect outcome and their P -value were listed in the node-splitting table. Treatments for each endpoint were ranked by their surface under the cumulative ranking curve (SUCRA) value. A heat plot was created to illustrate the contribution of raw data and the inconsistency between direct and indirect comparisons. Results: According to the search strategy, 697 publications were identified, and 25 records were included, involving 3,032 patients with tibia shaft fractures. Seven common surgical or non-surgical treatments, including reamed intramedullary nailing (RIN), un-reamed intramedullary nailing (UIN), minimally reamed intramedullary nailing (MIN), ender nailing (EN), external fixation (EF), plate, and cast, were compared, in terms of time to union, reoperation, non-union, malunion, infection and implant failure. Plate performed relatively better for time to union, while cast might be the best choice in close cases to reduce the risks of reoperation, non-union, malunion, and infection. To prevent implant failure, EN seemed to be better. Conclusion: Cast might have the highest probability of the most optimal choice for tibia shaft fracture in close cases, while reamed intramedullary nailing ranked second. [ABSTRACT FROM AUTHOR]

Purpose: To identify predictive biomarkers for radiosensitization and prognosis of esophageal squamous cell carcinoma (ESCC). Materials and methods: A total of 150 advanced stage ESCC patients were treated with preoperative radiotherapy. The protein levels of Dicer 1, DNA methyltransferase 1 (Dnmt1), and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and the mRNA levels of Dicer 1, Dnmt1, and let-7b microRNA (miRNA) were measured in ESCC tumor tissues before and after radiotherapy. Global DNA methylation was measured and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed. Results: Negative Dicer 1, Dnmt1, and DNA-PKcs protein expression were observed in 72%, 67.3%, and 50.7% of ESCC patients, respectively. Primary Dicer 1 and Dnmt1 expression positively correlated with radiation sensitization and longer survival of ESCC patients, while increased Dicer 1 and Dnmt1 expression after radiation correlated with increased apoptosis in residual tumor tissues. Dicer 1 and Dnmt1 expression correlated with let-7b miRNA expression and global DNA methylation levels, respectively. In contrast, positive DNA-PKcs expression negatively correlated with radiation-induced pathological reactions, and increased DNA-PKcs expression correlated with increased apoptosis after radiation. Conclusion: Global DNA hypomethylation and low miRNA expression are involved in the sensitization of ESCC to radiotherapy and prognosis of patients with ESCC. [ABSTRACT FROM AUTHOR]

Highlights: [•] Activation of autophagy of colon cancer stem cells is involved in chemoresistance. [•] Activation of autophagy of colon cancer stem cells is mediated by Cdx1. [•] Overexpression of Cdx1 inhibits p53-induced cell death. [•] Silencing of Cdx1 expression leads to death of cancer stem cells in vitro and in vivo. [ABSTRACT FROM AUTHOR]

From September 2009 to September 2010 we undertook a survey of the Endangered François’ langur Trachypithecus francoisi in south-east Chongqing to compare the species' present status with historical records from the 1990s. Based on a literature review, interviews with local people and our survey we found François’ langurs in only three isolated sites, across four counties, with a total area of occurrence of c. 57 km2. The total population was estimated to be c. 200 individuals in 27 mixed sex groups. There were 21 groups (149 individuals) within a reserve (Jinfoshan), and four groups (36) in Furongjiang and two groups (13) in Heishangu were not within any reserve. The primary threat to the langur is habitat loss caused by traditional firewood use and agricultural encroachment but there is also increasing loss of forest to hydroelectric projects and construction of tourism infrastructure and facilities such as highways, hotels and telephone lines. The three sites in southern Chongqing province are adjacent to four areas in north-east Guizhou province that contain c. 60% of the wild population of the species in China. The seven sites combined are the main stronghold of this species and the geographical proximity of the sites raises the possibility of setting up ecological corridors between some of them. [ABSTRACT FROM AUTHOR]