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[en] The present study was undertaken to examine the effect of marrow preservation at 4 degrees C on subsequent long-term culture, which evaluates both hematopoietic precursor cells and hematopoietic microenvironmental cells. Storage of unfractionated marrow was superior to storage of buffy-coat cells in tissue culture medium with 20% fetal calf serum. CFU-C recovery in unfractionated marrow was 48.4% at four days and 21.4% at seven days. Long-term marrow cultures from cells stored at 4 degrees C for up to seven days produced CFU-C for up to seven weeks and established confluent marrow stromal cell layers. Suspension cultures of marrow cells preserved at 4 degrees C for seven days cultured with irradiated allogeneic marrow stromal cell layers from normal long-term marrow cultures showed significantly increased CFU-C production from week 2 to week 5 when compared with the control cultures without adherent cell layers. These data suggest that marrow storage at 4 degrees C for up to seven days preserves early hematopoietic precursor cells and microenvironmental cells and may be used for autologous rescue from marrow ablative therapy
[en] Radiosensitivity of spleen CFU depositing in bone marrow and in the spleen does not differ essentially. For CFU forming colonies in the spleen the Dsub(o) value varies within 105-120 R. For CFU forming colonies in bone marrow the value of Dsub(o) is 120-135 0. It is suggested that in bone marrow there are 2 fractions of CFU one of which is radiosensitive and the other radioresistant. It is mainly radiosensitive fraction of CFU that is localized, in the spleen
[en] Preservation of tissue-engineered (TE) bone is one of the key problems needed to be solved for its clinic application and industrialization. Traditional cryopreservation has been restricted because of the damages caused by ice formation and solution. Hypothermic preservation at 4 0C has been widely used for the preservation of transplanted organ despite potential negative effects on viability of cells and tissue. 37 0C is the best temperature for maintaining cellular bioactivities. However, 37 0C also has a potential negative effect on preserved cells due to consumption of nutrients and accumulation of by-products. No studies have reported which temperature is more suitable for the preservation of TE bone constructs. The current study explored the feasibility of preservation of TE bone constructs in sealed osteogenic media at 37 0C and 4 0C. Human bone marrow stromal cells (hBMSCs) were seeded into partially demineralized bone matrix (pDBM) scaffolds and cultured for 7 days to form TE bone constructs. The constructs were preserved in sealed osteogenic media at either 37 0C or 4 0C for 5, 7, 9 and 11 days, respectively. Growth kinetics, viability, metabolism and osteogenic capability were evaluated to explore the feasibility of preservation at 37 0C and 4 0C. The constructs cultured in osteogenic media at humidified 37 0C/5%CO2 served as the positive control. The results demonstrated that all the constructs preserved at 4 0C showed negative osteogenic capability at all time points with a much lower level of growth kinetics, viability and metabolism compared to the positive control. However, the constructs preserved at 37 0C showed good osteogenic capability within 7 days with a certain level of growth kinetics, viability and metabolism, although an obvious decrease in osteogenic capability was observed in the constructs preserved at 37 0C over 9 days. These results indicate that the preservation of TE bone constructs is feasible at 37 0C within 7 days in sealed osteogenic media.
[en] The probability that bone-marrow transplantation will be beneficial after nuclear accidents depends on several factors, including circumstances of the accident, degree of damage in other body systems, and radiation dose. Transplant-related variables, such as donor-recipient histocompatibility and post-transplant immune suppression, are also important. The benefits of transplantation may result from transient or permanent haemopoietic reconstitution. The balance of potential benefits versus risks should be individually calculated for each accident and each patient; generalisations are likely to result in untenable conclusions. (author)