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INTRODUCTION: In recent years, both stromal vascular fraction (SVF) from adipose tissue and mesenchymal stem cells (MSC) from adipose tissues were extensively used in both preclinical and clinical treatment for various diseases. Some studies reported differences in treatment efficacy between SVFs and MSCs in animals as well as in humans. Therefore, this study is aimed to evaluate the immune modulation and angiogenic potential of SVFs and MSCs from the same SVF samples to support an explanation when SVFs or MSCs should be used. METHODS: The adipose tissue samples from ten female donors with consent forms were collected. SVFs from these samples were isolated according to the published protocols. The existence of mesenchymal cells that positive with CD44, CD73, CD90, and CD105 and endothelial progenitor cells that positive with CD31 and CD34 was determined using flow cytometry. Three samples of SVFs with similar percentages of mesenchymal cell portion and endothelial progenitor cell portion were used to isolate MSCs. Obtained MSCs were confirmed as MSCs using the ISCT minimal criteria. To compare the immune modulation of SVF and MSCs, the mixed lymphocyte assay was used. The lymphocyte proliferation, as well as IFN-gamma and TNF-alpha concentrations, were determined. To compare the angiogenic potential, the angiogenesis in quail embryo assay was used. The angiogenesis efficacy was measured based on the vessel areas formed in the embryos after 7 days. RESULTS: The results showed that all SVF samples contained the portions of mesenchymal cells and endothelial progenitor cells. MSCs from SVFs meet all minimal criteria of MSCs that suggested by ISCT. MSCs from SVFs efficiently suppressed the immune cell proliferation compared to the SVFs, especially at ratios of 1:4 (1 MSCs: 4 immune cells). MSCs also inhibited the IFN-gamma and TNF-alpha production more efficiently than SVFs (p < 0.05). However, in quail embryo models, SVFs triggered the angiogenesis and neovessel formation better than MSCs with more significant vessel areas after 7 days (p < 0.05). CONCLUSION: This study suggested that SVFs and MSCs have different potentials for immune modulation and angiogenesis. SVFs help the angiogenesis better than MSCs, while MSCs displayed the more significant immune modulation. These results can guide the usage of SVFs or MSCs in disease treatment.
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Introduction: Medical students have been serving as a key part of the frontline health workforce responding to the coronavirus disease 2019 (COVID-19) pandemic globally. Their contribution is especially important in the resource-scarce settings of developing nations such as Vietnam. Yet, the intention of medical students, in particular, nursing students, to participate in COVID-19 frontline prevention activities has not been well-understood. This study aimed to examine factors associated with the intentionto participate in COVID-19 frontline prevention activities among Vietnamese nursing students. Methods: A cross-sectional study was conducted on a total of 597 students in December 2020 in Hanoi, Vietnam. Information regarding the socioeconomic characteristics of participants, their source of COVID-19 related knowledge, and their perception and attitude toward participating in COVID-19 frontline activities [based on Theory of Planned Behavior (TPB)] was collected. A hierarchical regression model was employed to examine the association between intentions of students and associated factors. Results: A positive intention to participate in COVID-19 frontline prevention activities was found (mean score of 25.3 over 35; SD = 4.4; min = 5; max = 35). Attitude toward behavior, subjective norms, and perceived behavioral control (PBC) was found to be significantly associated with the intention of students. These variables explained the 37% variation in the intention of students in the model. Among three factors, subjective norm showed the strongest correlation with intention of students (ß = 0.358; p < 0.001). Obtaining information from official sources and community was also found to be positively correlated with intention to participate. Conclusion: Most of the respondents reported a positive intention to participate in COVID-19 frontline prevention activities. The findings suggested that the TPB was a good instrument to predict the intention to perform behavior among Vietnamese students. Enhancing the positive attitude of students, encouraging family and community supports, and providing adequately essential resources will contribute to optimizing the participation of students to confront COVID-19.