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Xiao-bing Fu

Publications and source records attributed to Xiao-bing Fu.

At least 19 recordsLinked to original sources
PubMed2006

[Mechanism of signal transduction of differentiation of mesenchymal stem cells into cytokeratin-expressing epidermoid cells].

OBJECTIVE: To investigate the role of the signal routes P38, ERK, and Rho in the differentiation of bone marrow mesenchymal stem cells (MSCs) into epidermoid cells. METHODS: (1) MSCs were separated from the bone marrow of Wistar rats by Ficoll-Pague lymphocyte separating medium and proliferated in culture medium. Then the MSCs were immunocytochemically stained to detect the expression of surface antigens. (2) The MSCs were randomly divided into 3 groups: control group; pure induction induced group, cultured with epithelial growth factor (EGF) added into the culture fluid, and Rho inhibition group, cultured with EGF and HA1077, a ROK inhibitor, added into the culture fluid. One, 3, 5, and 7 days later FC was used to detect the levels of phosphorylated P38 and ERK. (3) MSCs were randomly divided into 4 groups: control group, cultured with low-sugar DMEM complete culture fluid; pure induction group, cultured with supernatant of rat fibroblasts and EGF added into the culture fluid, p38 blocking group, with SB203580, inhibitor of P38 added into the culture fluid; and ERK blocking group, with PD98059, inhibitor of ERK added into the culture fluid. Seven days later, SP method was used to detect the expression of CK5/8 and CK19 induced by MSCs. (4) MSCs were randomly divided into 4 groups: control group; pure induction group, with supernatant of rat fibroblasts and EGF added into the culture fluid; and RHO blocking group, with HA1007 added into the culture fluid. Seven days later, FC was used to detect the expression of CK5/8 and CK19. RESULTS: (1) Both FC and immunocytochemistry showed that the MSCs were uniformly positive in CD29 and CD44, but did not express CD34 and CD45. (2) The phosphorylated P38 rate remained 0.01% in the control group. The phosphorylated P38 rate was 0.04%, significantly higher than that of the control group (0.01%, P < 0.05) at day 5, and then lowered to 0.01% at day 5 in the pure induction group; and became 6.17%, 4.13%, 3.97%, and 0.41% respectively at day 1, 3, 5, and 7, all significantly higher than those of the control group (all P < 0.05), in the Rho inhibition group. The phosphorylated ERK level was 4.23% in the control group; became 0.39% and 0.40% at day 3 and day 5 (both P < 0.05), and then returned to 5.10% at day 7 in the pure induction group; and was not significantly changed at days 1, 3, and 5, and then became 0.41%, significantly lower than that of the control group (P < 0.05), in the Rho blocking group, (3) The control group was CK5/8 and CK19 negative. The CK5/8 and CK19 rates at day 7 of the pure induction group were 3.01% and 6.47% respectively, both significantly higher than those of the p38 inhibition group (1.43% and 5.41% respectively, both P < 0.05). The CK5/8 and CK19 expression rates of the ERK inhibition group were 5.54% and 7.56% respectively, both significantly higher than those of the pure induction group (both P < 0.05), (4) The CK5/8 and CK19 expression rates of the HA1077 group were 21.65% and 39.41% pure, both significantly higher than those of the pure induction group (1.81% and 10.19% respectively, both P < 0.05). CONCLUSION: p38 route may play an active role in the differentiation of MSCs into epidermoid cells. Blocking of the upstream signal Rho may enhance the activation of p38 route and then promote the differentiation of MSCs into epidermoid cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed2006

[Effect of acidic fibroblast growth factor on mitogen-activated protein kinase activity in small intestinal epithelium after ischemia/reperfusion injury in rat].

OBJECTIVE: To investigate the effect of acidic fibroblast growth factor (aFGF) on p44/p42 mitogen-activated protein kinase (p44/p42 MAPK, extracellular signal-regulated protein kinase, ERK1/2) activity in small intestinal epithelium in rat after ischemia/reperfusion (I/R) injury and its relation with the change in small intestinal epithelium in rat after I/R injury as well as the change in proliferation of epithelial cells. METHODS: Superior mesenteric artery (SMA) was occluded to produce ischemia of the intestine for 45 minutes followed by reperfusion to reproduce I/R injury. One hundred and thirty-two Wistar rats were randomly divided into sham-operation group, I/R group, aFGF treatment group (4 microg of aFGF was injected into jugular vein after reperfusion), and PD98059 (antagonist of ERK 1/2) pretreatment group (7.5 microg of PD98059 was injected via tail vein before ischemia and 4 microg of aFGF was injected via jugular vein after reperfusion). The activity of ERK1/2 and proliferation rate of small intestinal epithelial cells were determined before ischemia and 15 minutes, 30 minutes, 1 hour, 2 hours, 6 hours, 12 hours and 24 hours after reperfusion. RESULTS: The activity of ERK1/2 in small intestinal epithelium was higher in aFGF treatment group than in I/R control group, and the proliferation rate in small intestinal epithelial cells was significantly enhanced in aFGF treatment group. PD98059, the specific inhibitor of ERK1/2, inhibited ERK1/2 activity and reduced the proliferation rate of small intestinal epithelial cells in aFGF treatment group. CONCLUSION: aFGF can promote small intestinal epithelial cell proliferation in I/R injury rats, and this may be related to activation of ERK1/2 in small intestinal epithelium.

Animals↗
PubMed2006

[Changes in tumor necrosis factor-alpha mRNA expression in peripheral polymorphonuclear leukocyte and tissues during posttraumatic sepsis].

OBJECTIVE: To evaluate the changes in tumor necrosis factor-alpha (TNF-alpha) mRNA expression in peripheral polymorphonuclear leukocyte (PMNs) and tissues after cecal ligation puncture (CLP) in rats. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect TNF-alpha mRNA expression in peripheral PMNs and tissues. RESULTS: The TNF-alpha mRNA expression in peripheral PMNs rose gradually after CLP, and it began to decrease after reaching the peak at 48 hours, but it was still higher than normal. The elevation of TNF-alpha mRNA expression was first limited in the regional tissues (P<0.01 at 12 hours after CLP and peaked at 24 hours in the intestine), then it entered the blood circulation later to affect the sensitive organs--lungs and livers (P<0.01 at 24 hours after CLP and peaked at 48 hours in the lung; P<0.05 at 24 hours after CLP and peaked at 48 hours in the liver). CONCLUSION: The rise of TNF-alpha mRNA expression plays an important role in pathogenesis of sepsis.

Animals↗
PubMed2006

[Isolation, culture and identification of adult epidermal stem cell].

OBJECTIVE: To explore and establish a new method of isolation, culture, and identification of adult epidermal stem cell in vitro for the provision of seed-cells in tissue engineering of skin. METHODS: Epidermis was obtained by digesting human foreskin with protease and it was dissociated into single cells with trypsin and ethylenediaminetetraacetic acid (EDTA). These single epidermis cells were inoculated onto human collagen IV coated flasks and cultured at 37 degrees C in a humidified atmosphere containing 5% CO(2). The nonadherent cells were rinsed off 10-15 minutes after inoculation. The adherent cells were observed under phase contrast microscope and electron microscope, and they were identified with immunocytochemical methods. Cell cycles of the adherent cells were determined with flow cytometry. RESULTS: With phase contrast microscope, the rapidly adherent cells were observed to form colonies 24 hours after inoculation. Immunocytochemistry showed the rapidly adherent cells were positive for beta1-integrin and keratin 19. Cell cycles showed that about 86.83% cells were in resting state/pre-DNA-synthetic gap (G0/G1 phase). Electron microscopy revealed that the rapidly adherent cells were immature. CONCLUSION: This study shows that adult epidermal stem cells could be isolated and cultured in vitro successfully.

Adult↗
PubMed2006

[Expression of matrix metalloproteinases and their inhibitors in fetal skin and their biological significance].

OBJECTIVE: To investigate the expression characteristics of matrix metalloproteinases (MMP-2, MMP-3, MMP-9) and tissue inhibitor of metalloproteinase (TIMP-1, TIMP-2) in developing fetal skin and their potential biological significance. METHODS: Skin of 24 cases of fetuses with different gestational age (12-40 weeks) were obtained, embedded with paraffin wax, and sectioned. Immunohistochemistry and pathological methods were used to detect the expression intensity and distribution of MMP-2, MMP-3, MMP-9, TIMP-1 and TIMP-2. RESULTS: Positive immunohistochemical signals of MMPs and TIMPs could be found in fetal skin at different gestational periods. These proteins mainly located in the cytoplasm of epidermal cells, fibroblasts, epithelial cells of hair follicles and sweat glands and vascular endothelial cells. In earlier gestational fetal skin (12-18 weeks), the expression levels of MMP-2, MMP-3 and MMP-9 were high. Along with the advancement in gestational age, the positive rates of these three proteins in skin were lowered, and in later gestational fetal skin (27-40 weeks) the expression rates were significantly decreased compared with those in earlier gestational fetal skin (all P<0.05). On the contrary, protein expression levels of TIMP-1 and TIMP-2 were apparently lower in earlier versus later gestational skin (both P<0.05). CONCLUSION: MMP-2, MMP-3, MMP-9, TIMP-1 and TIMP-2 might be involved in the skin development and maintenance of cutaneous structure and function. Higher expression of MMP-2, MMP-3 and MMP-9 and lower protein levels of TIMP-1 and TIMP-2 may provide an antiscarring signal in healing of wound during early periods of gestation.

Fetus↗
PubMed2006

[Relationship between the proliferation and immunoinduction of epithelial cells and the destruction of hair follicles and sebaceous glands in keloids].

OBJECTIVE: To investigate the influence of biological behavior of epithelial cells on the hair follicles and sebaceous glands (HFSG) structure in keloids (K). METHODS: The expression of intercellular adhesion molecule (ICAM)-1, D-related human leucocyte antigen (HLA-DR), and cytokeratin (CK) 14 on epithelial cells and the amount of activity T-lymphocytes were detected in specimens of keloid edge and normal skin with immunohistochemical and histological methods. RESULTS: In comparison with normal skin specimens, epithelial cells were proliferated in K-HFSG presented structural aberration and disintegrate or abnormally to form solid-epithelial island-like structure, and the density of HSFG with hyperplasia and the ageing scar in keloids was apparently decreased. They strongly expressed ICAM-1, HLA-DR, and CK14 in the epithelial cells, there were many immunologic cells which expressed CD4, CD45RO, and interferon (IFN)-gamma around the K-HFSG. The expressed level of epithelial cells was positively correlated with the density of immunologic cells nearby K-HFSG. CONCLUSION: It could be concluded that the reactivity with hyperplasia and immunoinduction of epithelial cells might be associated with the destruction of the some HFSG structure in the keloids.

Adolescent↗
PubMed2006

Progress of cellular dedifferentiation research.

Differentiation, the stepwise specialization of cells, and transdifferentiation, the apparent switching of one cell type into another, capture much of the stem cell spotlight. But dedifferentiation, the developmental reversal of a cell before it reinvents itself, is an important process too. In multicellular organisms, cellular dedifferentiation is the major process underlying totipotency, regeneration and formation of new stem cell lineages. In humans, dedifferentiation is often associated with carcinogenesis. The study of cellular dedifferentiation in animals, particularly early events related to cell fate-switch and determination, is limited by the lack of a suitable, convenient experimental system. The classic example of dedifferentiation is limb and tail regeneration in urodele amphibians, such as salamanders. Recently, several investigators have shown that certain mammalian cell types can be induced to dedifferentiate to progenitor cells when stimulated with the appropriate signals or materials. These discoveries open the possibility that researchers might enhance the endogenous regenerative capacity of mammals by inducing cellular dedifferentiation in vivo.

Animals↗
PubMed2005

[Cellular phenotype conversion induced by co-culture of human mesenchymal stem cells cocultured with human sweat gland cells].

OBJECTIVE: To investigate the cellular phenotype conversion during human mesenchymal stem cells (hMSCs) cocultured with injured human sweat gland cells (hSGCs) in vitro. METHODS: HMSCs and hSGCs were isolated and cultured and expanded respectively. The antigens expression of hMSCs and hSGCs were detected by two-steps immunocytochemistry. HMSCs were labeled with BrdU. The hSGCs were heat-shocked at 47 degrees C for 40 min when they reached 70% confluency, then cooled for 1-2 h at 37 degrees C and (1 - 2) x 10(5) BrdU-labeled hMSCs were added before incubation for up to 2 weeks. The cocultures were observed by phase contrast microscopy and detected by double-staining immunocytochemistry using CEA and BrdU as primary antibodies. RESULTS: The cultured hMSCs and hSGCs were clonogenic growth. HMSCs were positive for anti-CD44 and anti-CD105 staining and negative for anti-CD34 and anti-CEA staining. HSGCs express CK7, CK18, CK19 and CEA. The positive rate of BrdU labeled-hMSCs was 90%. The majority of hSGCs lost cell-cell contact after heat-shock. 2 weeks after cocultured, some cocultured cells were positive for both anti-CEA and anti-BrdU staining and some cocultures had more than two nuclei which stained with two different colors by double-staining immunocytochemistry. Statistic results showed 1%-5% of the hMSCs added to the coculture system were recovered as double-staining cells expressing BrdU and CEA while only 0.01%-0.05% cells stained with two different colors in nuclei. The multi-nucleated cells were wide and flatten. CONCLUSION: HMSCs could differentiate into hSGCs in vitro under injured microenvironment. The mechanisms of which may be that hMSCs differentiate into hSGCs directly or by cell fusion, even nucleus fusion.

Bone Marrow Cells↗
PubMed2005

[Investigation of mesenchymal-epithelial transdifferentiation in the morphogenesis mechanism of embryonic epidermic cells].

OBJECTIVE: To study the relationship between the morphologic mechanism of human embryonic epidermic cells and mesenchymal-epithelial transformation (MET) and its modulation factor. METHODS: Morphological occurrence of epidermis was detected with histologic methods in earlier period [estimated gestational age (EGA) 6-14 weeks] human embryonic skin samples. At the same time, the characteristic expression and their distribution markers of mesenchymal cells [vimentin and alpha-smooth muscle actin (alpha-SMA)], embryonic specific epidermic protein CK8&18, specific protein of epidermic stem cell CK19, transforming growth factor-beta1) (TGF-beta1) and its receptor (TGFbetaRI) in embryonic epidermis were examined with immunohistochemistry and indirect-immunofluorescent doble-labelling method. RESULTS: During EAG 6-8 weeks, ectodermal cells containing Vim+/alpha-SMA(-) were found to transform into epidermal stem cells with CK8&18+/CK19+. In ectodermal cells, protein expression density of TGFbetaRI was moderate (+ +), while positive signal of TGFbeta1 was weak (+/-). After EGA10 weeks, epidermal cells showed typical morphological characteristics. CONCLUSIONS: At EGA 6-8 weeks, human embryonic skin epidermal cells began to form through MET, in which the signal pathway mediated by TGFbetaRI might play important roles, but the role of TGFbeta1 need to be further studied.

Cell Differentiation↗
PubMed2005

[Protective effects of modified recombinant human acidic fibroblast growth factor on small intestine after ischemia/reperfusion injury in rats].

OBJECTIVE: To explore the protective effect of modified recombinant human acidic fibroblast growth factor (rhaFGF) on small intestinal after ischemia/reperfusion (I/R) injury in rats. METHODS: The clamp on the superior mesenteric artery (SMA) was removed after clamping it for 45 minutes to replicate I/R injury of the intestine in the rat. Rats were then divided randomly into sham operation group, normal saline treatment group and rhaFGF treatment group, in which the rats of the normal saline treatment group were injected 0.1 ml of normal saline and that of the rhaFGF group were given 4 microg of rhaFGF immediately after reperfusion. The content of D-lactate in the plasma was determined and the changes in intestinal pathology were observed. At the same time, the rates of apoptosis of intestinal epithelial cells were assessed 2, 6, 12 and 24 hours after I/R, and compared to the sham operation group. RESULTS: The plasma content of D-lactate in the saline treatment group at 6 hours after I/R reached (0.34+/-0.09) mg/L and was significantly higher than that in the rhaFGF treatment group((0.23+/-0.07)mg/L, P<0.05). It was shown histologically that the intestinal structures were damaged more seriously in saline treatment group than in rhaFGF group. The apoptosis rates in the saline treatment group and rhaFGF group were elevated significantly, peaking at 12 hours after I/R injury((62.8+/-1.7)% in saline group and (42.5+/-2.6)% in rhaFGF treatment group), then the rate began to fall. There was statistically significant difference between the two groups at 12 hours after I/R injury. CONCLUSION: rhaFGF can reduce content of D-lactate in the plasma and rate of apoptosis of epithelial cells in the intestine after I/R injury, thus it seems to afford a protective effect on the small intestine after I/R injury in rats.

Animals↗
PubMed2005

[Isolation and purification of eccrine sweat glands in human skin].

OBJECTIVE: To investigate the method of isolation and purification of epithelial cells of human eccrine sweat gland in vitro. METHODS: Through digesting human skin with collagenase type II, cells of human eccrine sweat gland were isolated. Highly purified gland cells were obtained through transferring into the conditioned medium with a micropipette for at least three times under an inverted microscope. Primary culture was started immediately after purification. Cells could be further purified by enzyme-digestion to eradicate the fibroblasts. RESULTS: Collagenase type II could digest dermal collagen with little damage to gland cells. Isolated cells from human sweat glands were adherent to the wall of culture flask, and they grew well in cultures. The problem of contamination by tissue debris and other cells such as fibroblast could be overcome. CONCLUSION: Isolation and purification of human sweat gland cells in vitro are still facing tough problems. Gland cells are successful to isolate and cultivate without contamination.

Cell Culture Techniques↗
PubMed2005

[Effects of adipose tissue extract on rat skin regeneration in vitro].

OBJECTIVE: To investigate the effects of adipose tissue extract on growth of rat skin in vitro. METHODS: Neonatal rat skin (area of 2 mm x 2 mm) was cultured in Dulbecco's modified Eagle's medium (DMEM) containing 10% adipose tissue extract and 10% phosphate buffered solution (PBS). After being cultured for 6 days, the area of skin was measured. RESULTS: Skin in both groups grew in area. With the addition of adipose tissue extract, the skin measured (8.43+/-1.40) mm2 in area after 6 days, and it was approximately 2 times of that of PBS group, in which the skin area was (4.18+/-1.11) mm2. The difference was statistically significant (P<0.05). CONCLUSION: Adipose tissue extract promote skin growth, which may be attributed to the presence of some growth factors in the extract.

Adipose Tissue↗
PubMed2005

[Culture and identification of human skin fibroblasts].

OBJECTIVE: To explore the method of isolation, cultivation, and identification of human skin fibroblasts in vitro. METHODS: By digesting human skin with collagenase type II to isolate human eccrine sweat glands. The fibroblasts grew along with the growth of eccrine sweat gland cells,and they were separated by digesting with 0.25% trypsin and 0.02% ethylenediaminetetraacetic acid (EDTA). Dulbecco's modified Eagle's medium (DMEM) was the basic culture medium, being supplemented with fetal bovine serum (10%), penicillin (100 kU/L), and streptomycin(100 mg/L) Fibroblasts were incubated at 37 centigrade in a humidified atmosphere of 5% CO2 and 95% air in the incubator. Cellular morphologies were observed by inverted phase contrast microscopy and hematoxylin-eosin staining, and the cultured cells were identified by vimentin immunostaining and chromosome analysis. RESULTS: The isolated fibroblasts could grow and proliferate in vitro, and immunostaining of vimentin was positive in cultured fibroblasts and the number of chromosome was 46. CONCLUSION: Acquired human skin fibroblasts can be cultured in stable condition in vitro, and sufficient and reliable target cells can be obtained for the study of the mechanisms of wound healing at molecular level.

Cell Culture Techniques↗
PubMed2005

[Protective effects of acidic fibroblast growth factor on intestinal ischemia/reperfusion in rats].

OBJECTIVE: To observe the change in hepatic and renal functions, change in the plasma D-lactate level, and the expression of proliferating cell nuclear antigen (PCNA) after intestinal I/R injury, so as to explore the effects of reconstructive human acid fibroblast growth factor(aFGF) on intestinal I/R injury in rats. METHODS: One hundred and twenty-six Wistar rats were divided into sham-operated, ischemia (45 minutes) plus reperfusion, reconstructive human aFGF treatment (2, 4, 8 microg aFGF) and wild type aFGF(2, 6, 12, and 24 hours, respectively) groups. Hepatic and renal functions and the levels of plasma D-lactate were determined and the expression of PCNA was assessed. RESULTS: Compared with all other groups, bowel barrier function and hepatic and renal functions showed most marked deterioration in sham-operated group. The damages were less marked in reconstructive human aFGF group compared with other groups 24 hours after ischemia/reperfusion of the intestine, and the protective effect was best shown when 4 microg of aFGF was given. The trend of expression of PCNA was similar to that of changes in D-lactate level. CONCLUSION: Wild type reconstructive human aFGF treatment significantly improves the outcome of ischemia/reperfusion injury to the intestine, and the effect is dose-dependent.

Animals↗
PubMed2004

[Study on the potentiation of bone marrow mesenchymal stem cells involved in sebaceous duct formation].

OBJECTIVE: To investigate the feasibility of differentiation of bone marrow mesenchymal stem cells (MSCs) into skin appandence. METHODS: Porcine MSCs were isolated from porcine marrow and grown in vitro. After labeling with BrdU, MSCs were engrafted to porcine skin. At 1, 2, 4 weeks after the transplantation, immunohistochemical examinations were carried out to detect the positive staining of BrdU and cytokeratin. RESULTS: A few sebaceous duct cells, which expressed cytokeratin, were also BrdU positive, and these cells were considered may to be transplanted MSCs-derived cells. CONCLUSION: Porcine MSCs might have the potential to differentiated into sebaceous duct cells in skin.

Animals↗