Utility investigation of automated techniques in hematopoietic progenitor cell count and viability assessment in the Good Manufacturing Practice (GMP) settingg

Aim: To compare our parameters as regards: i) cell count via two different automated cell count techniques, and ii) viability via automated trypan blue exclusion and 7-aminoactinomycin D (7-AAD) staining. Method: We used the trypan blue exclusion technique and an automated cell counter and for viability testing, and the trypan blue exclusion technique and the 7-AAD evaluation by flow cytometry. The trypan blue exclusion and the radio frequency techniques were used for automated cell counting. Flow cytometric analysis was performed by evaluating the yielded cellular products for 7-AAD uptake during the cell count of CD34+ cells. Results: The mean values for cell count were estimated as 3.44±1.22x106/ml (range, 2.48-5.71x106/ml) and 4.14±1.94x106/ml (range, 1.77-7.43x106/ml) for the trypan blue exclusion and radio frequency techniques, respectively. Additionally, the mean values for viability analyses via the automated trypan blue exclusion and 7-AAD were 93.38±6.09% (range, 79.00-98.00%) and 99.49±0.60% (range, 98.40-100.00%), respectively. Conclusions: Our study has responded to two fundamental questions: whether the results of both of the automated techniques for cell count correspond with each other, and whether the results of the automated viability assessment conform those of the 7-AAD technique during the manufacturing processes of cellular therapy products intended for clinical use. Even though we have the opportunity to use the hemocytometer in our laboratory setting, the automated trypan blue exclusion technique gives cell count results in concordance within the range of the expectations of our Quality Management System (QMS)

Application of fuzzy DEMATEL method for analyzing occupational risks on construction sites

The construction industry is known as a hazardous industry because of its complexity and strategic nature. Therefore, it is important to know the main causes of occupational accidents to prevent fatal occupational accidents in construction industry. At building construction sites, workers performing tasks are continuously exposed to risks, not only emerging from their own mistakes but also from the mistakes of their co-workers. A great deal of studies investigating risks and preventing occupational hazards for the construction industry has been carried out in the literature. The quantitative conventional methods mostly use either probabilistic techniques or statistics, or both, but they have limitations dealing with the ambiguity and fuzziness in information. In this study, to overcome these limitations, an applicable and improved approach, which helps construction managers to propose preventive measures for accidents on construction sites, is proposed to simplify the risk assessment. It is shown that the Fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL) method can evaluate causal factors of occupational hazards by a cause–effect diagram and improve certain safety measures on construction sites. In addition, sensitivity analysis is conducted to verify the robustness of the results

Application of Fuzzy DEMATEL Method for Analyzing Occupational Risks on Construction Sites

The construction industry is known as a hazardous industry because of its complexity and strategic nature. Therefore, it is important to know the main causes of occupational accidents to prevent fatal occupational accidents in construction industry. At building construction sites, workers performing tasks are continuously exposed to risks, not only emerging from their own mistakes but also from the mistakes of their co-workers. A great deal of studies investigating risks and preventing occupational hazards for the construction industry has been carried out in the literature. The quantitative conventional methods mostly use either probabilistic techniques or statistics, or both, but they have limitations dealing with the ambiguity and fuzziness in information. In this study, to overcome these limitations, an applicable and improved approach, which helps construction managers to propose preventive measures for accidents on construction sites, is proposed to simplify the risk assessment. It is shown that the Fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL) method can evaluate causal factors of occupational hazards by a cause–effect diagram and improve certain safety measures on construction sites. In addition, sensitivity analysis is conducted to verify the robustness of the results

Osteogenic differentiation of mesenchymal stem cells using hybrid nanofibers with different configurations and dimensionality

[EN] Novel, hybrid fibrinogen/polylactic acid (FBG/PLA) nanofibers with different configuration (random vs aligned) and dimensionality (2¿D vs 3¿D environment) were used to control the overall behavior and the osteogenic differentiation of human adipose¿derived mesenchymal stem cells (ADMSCs). Aligned nanofibers in both the 2¿D and 3¿D configurations are proved to be favored for osteodifferentiation. Morphologically, we found that on randomly configured nanofibers, the cells developed a stellate¿like morphology with multiple projections; however, time¿lapse analysis showed significantly diminished cell movements. Conversely, an elongated cell shape with advanced cell spreading and extended actin cytoskeleton accompanied with significantly increased cell mobility were observed when cells attached on aligned nanofibers. Moreover, a clear tendency for higher alkaline phosphatase activity was also found on aligned fibers when ADMSCs were switched to osteogenic induction medium. The strongest accumulation of Alizarin red (AR) and von Kossa stain at 21 days of culture in osteogenic medium were found on 3¿D aligned constructs while the rest showed lower and rather undistinguishable activity. Quantitative reverse transcription¿polymerase chain reaction analysis for Osteopontin (OSP) and RUNX 2 generally confirmed this trend showing favorable expression of osteogenic genes activity in 3¿D environment particularly in aligned configuration.Contract grant sponsor: CIBER-BBN Spain (project BIOSURFACES) Contract grant sponsor: European Commission through the FP7 Industry-Academia Partnerships and Pathways (IAPP) project FIBROGELNET; contract grant number: PAP-GA-2012-324386 Contract grant sponsor: Spanish Ministry of Economy and Competitiveness; contract grant number: MAT 2015-69315-C3 MYOHEAL Contract grant sponsor: The Scientific and Technological Research Council of Turkey (TUBITAK); contract grant number: 11S497Gugutkov, D.; Awaja, F.; Belemezova, K.; Keremidarska, M.; Krasteva, N.; Kyurkchiev, S.; Gallego-Ferrer, G.... (2017). Osteogenic differentiation of mesenchymal stem cells using hybrid nanofibers with different configurations and dimensionality. Journal of Biomedical Materials Research Part A. 105(7):2065-2074. https://doi.org/10.1002/jbm.a.36065S20652074105