[Exogenous gene expression in vitro and in vivo in bone marrow mesenchymal stem cells modified by hPDGF-A and hBD(2)].

The objective of this study was to investigate the expression of exogenous hPDGF-A and hBD(2) in gene-modified bone marrow mesenchymal stem cells (BM-MSCs) in vitro and in vivo. Recombinant adenovirus vector expressing hPDGF-A/hBD(2) genes was constructed and packaged into virion. Primary isolated and cultured BM-MSCs were transfected by using hPDGF-A hBD(2), then the expressions of exogenous hPDGF-A/hBD(2) were detected by immunocytochemical staining in vitro.

Progress in research on radiation combined injury in China.

The significant feature of radiation combined injury is the occurrence of a combined effect. For decades our institute has focused on studying the key complications of radiation-burn injury, including shock, suppression of hematopoiesis and immunity, gastrointestinal damage and local refractory wound healing. Here we summarize recent advancements in elucidating the mechanisms of and potential treatments for radiation combined injury.

[Effect of calpain inhibitor I on ikappaBalpha expression and cytokine secretion in RAW264.7 cells attacked with LPS].

Aim: To explore the effect of calpain inhibitor I(CI-I) on ikappaBalpha expression and cytokine secretion in RAW264.7 cells after LPS attack.

Methods: RAW264.

[The effects of burn serum on the erythropoiesis and granulopoiesis in bone marrow in mice].

Objective: To observe the effects of burn serum on the erythropoiesis and granulopoiesis in bone marrow in mice, and to explore the possible underlying mechanism.

Methods: Murine bone marrow cell (BMC) strain was prepared routinely and was employed in the establishment of the culture system of colony forming units of erythrocytes, or granulocytes and monocytes. To both sets of culture system normal murine serum (N group) and burn serum, which was collected from the mice with 15% full thickness burn at 12 postburn hours (PBH) and 1, 3, 5, 7 and 10 postburn days (PBD), (burn serum group) was added.

[Experimental study on the myogenic differentiation of marrow mesenchymal stem cells in the local muscle tissues].

Objective: To investigate the myogenic differentiation of mesenchymal stem cells (MSCs) after being transplanted into the local muscle tissues.

Methods: The serious muscle-injured model was established by the way of radiation injury, incising, and freezing injury in 36 mice. Purified MSCs derived from bone marrow of male mouse and MSCs induced by 5-azacytidine (5-Aza-CR) were transplanted into the local of normal muscle tissues and injured muscle tissues of female mouse.

[The role of p38 on the differentiation of MSCs to myoblasts].

Aim: Inducing mesenchymal stem cells (MSCs) differentiate to myoblasts with 5-azacytidine(5-Aza-CR), investigating the expression of Myf5 and the role of the signal transduction case of p38 in all the course of differentiation.

Methods: Separating and purifying bone marrow-derived MSCs, inducing MSCs differentiation to myoblasts with 10 micromol/L 5-Aza-CR, assaying the gene expression time of Myf5 with RT-PCR method, the antigen expression of myosin with immunohistochemistry method and observing the changes of the activity of phosphorylation p38 before and after inhibited by SB203580 with Western-blot method.

Results: MSCs begin to express Myf5 delayed to the 9th day after inhibited by SB203580.

Effects of dermal multipotent cell transplantation on skin wound healing.

There is increasing evidence that dermis contains adult multipotent stem cells. To investigate the effects of dermis-derived multipotent cells on wound healing, we transplanted a clonal population of dermis-derived multipotent cells (termed as DMCs) by topical and systemic application into the skin wound of rats with simple wounds and rats with combined wound and radiation injury. Our results suggest that both topical and systemic transplantation of DMCs accelerate the healing process in rats with a simple wound; the promoting effect by topical transplantation occurs earlier than systemic transplantation.

[Promoting effects of stromal cells on hematopoietic reconstitution capability of bone marrow cells expanded under different conditions].

To explore the effects of bone marrow cells expanded under different conditions on hematopoietic reconstitution, in the liquid expanded cultural system with several cytokines and/or bone marrow stromal cell layers, the BMMNC of mice were expanded for 5 days. Then the expanded cells were transplanted into the lethal-dose irradiated mice via the caudal vein. The hematopoietic reconstitution of transplanted mice were evaluated by detecting the number of bone marrow nuclear cells and various colony forming cells.

Transplantation of dermal multipotent cells promotes survival and wound healing in rats with combined radiation and wound injury.

Combined radiation and wound injury occurs after severe nuclear accidents that accompany explosions or nuclear attacks. High doses of ionizing radiation can cause bone marrow aplasia and delay wound healing. Combined radiation and wound injury is very complex and is more difficult to deal with than single injuries.

Radioprotective effect of FLT3 ligand expression regulated by Egr-1 regulated element on radiation injury of SCID mice.

Objective: Hematopoietic factors have an important effect on the regulation of hematopoiesis by stimulating the proliferation of hematopoietic progenitor cells. Although the cytokines that stimulate hematopoiesis have also often proved to exert radioprotective effects, no definitive correlation has been found between the expression of these cytokines regulated by radio-inducible genes and their radioprotective effects. In the current experiments, we evaluated the radioprotective effects of the hematopoietic growth factors regulated by a radio-inducible promoter on radiation injury.

[Prospects of Research on Bone Marrow Mesenchymal Stem Cells].

Besides hematopoietic stem cells, bone marrow also contains another type of stem cells called mesenchymal stem cells (MSCs). With different induced conditions, MSCs have the ability to differentiate into a variety of nonhematopoietic tissue cells, including osteoblasts, chondroblast, adipocytes, myoblasts, astrocytes, and so on. MSCs can be readily obtained from bone marrow by their adhesion to plastic and expansion in culture.

Irradiation-induced apoptosis of mouse bone marrow stromal cells.

Objective: To study the apoptotic patterns of bone marrow stromal cells (BMSCs) after irradiation.

Methods: Apoptosis of BMSCs induced by (60)Co gamma irradiation was detected by both flow cytometry and electron microscopy.

Results: Compared with normal control group, no manifest changes in the apoptosis ratio occurred in BMSCs after 50 Gy irradiation (P>0.