Objective To introduce the basic research and cl inical appl ication of stem cells transplantation for treating diabetic foot. Methods The recent original articles about the stem cells transplantation for treating diabetic foot were extensively reviewed. Results Transplanted different stem cells in diabetic foot could enhanced ulceration heal ing in certain conditions, increase neovascularization and avoid amputation. Conclusion Stem cells transplantation for treating diabeticfoot may be a future approach．
Objective To investigate the current situation, problems of medicinal biotechnology in China, and to provide the relevant countermeasures for its development. Methods We surveyed the units which could carry out medicinal biotechnology projects in 30 provinces except Tibet, and compared the results with that in America.Results The questionnaire were returned from 25 provinces (83.4%), and there were 1 477 medicinal biotechnology projects carried out by 149 units in the past 10 years. These projects ranged from basic biotechnology to regenerative medicine and stem cell researches. The basic research projects constituted quite large percentage among all the projects. But the development levels in different areas were imbalanced, cross correlation with the development levels of economy. An echelon team of talents has been developed, most of them were trained in China. The invested capital differed considerably among units, in general the amounts were insufficient. Most invested capital came from the government. The number of patent application for projects based on independent-developed technology was small. This showed that project principals had a poor understanding of patents. More than half of units did not have a Bioethics Committee. From the search result for documents, the number of articles on stem research of China was close to that in America; and the number of articles on gene treatment and tissue engineering has already exceeded that of America. However, research on gene diagnosis of China was lagging far behind America. Conclusions An echelon team of talents has been developed, most of them are trained in China.We should give full play to the advantage of the distribution of qualified personal resources in developed economical areas so as to promote the applicability and popularity of medicinal biotechnology in less developed areas.Regarding to applicability and development, we should first develop applied technology to form the core competetiveness of basic research, technology development and application; we should also strengthen the training in ethics and regulation to establish a set of scientific assessment of medicinal biotechnology and management system.
Objective To review the advance in the experimental studies of microRNA(miRNA) and the relationship between miRNA and stem cells. Methods The related literature was reviewed, and the research findings of miRNA and stem cell were summarized. Results miRNA was noncoding small RNA (20-25 nt) involved in posttranscriptional change, that have been shown to regulate gene expressions. Ithas been reported that some kinds of miRNAs were likely important regulators forstem cells maintaining their state of selfrenewal，and play key roles in theirdifferentiation. Conclusion miRNA as regulation of gene expressions, can be served as a new way for stem cells research.
Objective To assess systematically the safety and ef fects of stem cell transplantation in stroke patients.Methods CENTRAL (April 2007), MEDLINE (1966 to April 2007), EMBASE (1980 to April 2007), and other databases were searched for RCT of the use of stem cell transplantation for patients with stroke. We critically appraised the quality of included studies according to Juny 2001. We assessed the effects of stem cell therapy on mortal ity, functional outcomes, cognitive functions, image changes, quality of life, and adverse effects by doing meta-analysis with The Cochrane Collaboration’ s Review Manager. Dichotomous outcomes were reported as relative risk and continuous outcome measures as weighted mean differences, with 95% confidence intervals.Results Three RCTs and one historical controlled trial were included involving a total of 69 participants. Only one trial reported the effect on mortality, but because of the small number of death it was not possible to detect any significant differences between stem cell transplantation and routine treatment (RR 0.11, 95%CI 0.01 to 2.31, P = 0.16). Three studies indicated a statistically significant improvement of some functional outcomes in patients treated by stem cell transplantation. Improvements of cognitive function were reported in another trial. One trial showed that the stem cell transplantation significantly improved qual ity of life compared with the control group. Conclusion The current evidence is insufficient to determine whether or not stem cell transplantation is a safe and effective therapy for stroke patients. High-quality, large-scale randomized trials are needed to assess the role of stem cell transplantation for stroke.
Purpose To investigate the development of embryonic stem cells (ESC)in the subretinal space． Methods ESC were cultivated in suspension for 4 days till they developed into cell aggregates,i.e.embryonic body(EB).ESC as well as EB combined with or without RA were respectively transplanted into vitreous cavity and subretina1 space in SD rats,and the subretinal transplanted eyes,transient ischemia-reperfusion injuries were made by ligating the ophthalmic artery for 40 seconds before the transplantation .The experimental eyes were enucleated for histological and immunohistochemical assays after 14～28 d. Results The EB was found to develope into photoreceptors induced by RA in the subretinal space under an ischemia-reperfusion condition，and EB transplantation without RA induction induced multiple differentiations in the subretinal space.The single injection of RA without EB induced hyperplasia of the neural retinal cells.ESC transplanted into vitreous cavity rapidly proliferated and developed into atypical hyperplastic mass. Conclusion EB derived from ESC can differentiate into photoreceptors induced by RA in the host subretinal space under an ischemia-reperfusion condition. (Chin J Ocul Fundus Dis，2000，16：213-284)
Objective To establish a culture method for human fetal retinal progenitor cells (RPC) in vitro. Methods Retinal neuroepithelium of 8-12-week human fetal were isolated and cultured in suspension and adherent methods. The passage cells were cultured and differentiated for 14 days with 5% fetal bovine serum without basic fibroblast growth factor (bFGF). The expressions of RPC and retinal final cells markers before and after the differentiation were detected by immunohistochemical analysis. Results The isolated cells cultured in suspension method congregated as the neurospheres and expressed the neuroectodermal marker nestin, but failed in passage and expansion; while the expression of nestin and serial passage were found in the cells cultured in adherent way. The differentiated passage cells expressed retinal final cells markers including glial fibrillary acid protein, beta;-tubulin and recoverin. Conclusions RPC derived from human fetal neural retina at the 8th12th week of gestation are capable of expansion and multipotentiality. (Chin J Ocul Fundus Dis, 2007, 23: 98-100)
Objective To summarize the research progress of CD90 protein. Methods The demestic and international published literatures related to CD90 protein in recent years were collected and reviewed. Results CD90 protein was involved in the cell-cell and cell-cytoplasm function. CD90 protein could promote axons growth and neural regeneration， and could induce apoptosis of thymus gland cells and stromal cells. CD90 protein participated in cell adhesion， extravasation and transfer， and the regulation of fibrosis. CD90 protein was a potential marker for cancer stem cells. Conclusion CD90 protein is very important in development of many diseases， and can provide a new molecular target to diagnose and treat neoplasms.
ObjectiveTo observe the effect of interleukin (IL) 10 modified endothelial progenitor cells (EPC) in diabetic retinopathy (DR). MethodsEPC cells were collected and cultivated from the bone marrow of rats and identified by immuno-fluorescence staining. EPC cells were infected with lentivirus (LV) of EPC-LV-IL10-GFP (EPC-LV-IL10-GFP group) or EPC-LV-NC-GFP (GFP group). EPC cells without lentivirus infection was the EPC group. Enzyme-linked immuno sorbent assay (ELISA) was used to measure the concentrations of tumor necrosis factor (TNF)-α, IL10, IL8 and vascular endothelial growth factor (VEGF) in the supernatant of these three groups. 168 male Wistar rats were divided into normal control group (28 rats), diabetes mellitus (DM) group (28 rats), DM-blank control group (56 rats) and DM-intervention group (56 rats). DM was introduced in the latter 3 groups by streptozotocin intravenous injection. Three months later, the rats in the DM-blank control group and DM-intervention group were injected with EPC-LV-NC-GFP or EPC-LV-IL10-GFP by tail vein, respectively. Immunohistochemistry was used to observe the GFP expression in rat retinas. The blood-retinal barrier breakdown was detected by Evans blue (EB) dye. The retinal histopathologic changes were observed by transmission electron microscope. The mRNA level of VEGF, matrix metallproteinases-9 (MMP-9), angiopoietin-1 (Ang-1), inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) in retina were measured by reverse transcription-polymerase chain reaction (RT-PCR). ResultsELISA showed that the levels of TNF-αand IL8 in the supernatant significantly decreased, while the levels of IL10 and VEGF increased (P < 0.05) in EPC-LV-IL10-GFP group. GFP expressed in the retina of blank control group and intervention group, mainly in the ganglion cell layer, inner nuclear layer and outer plexiform layer. The retinal blood vessel pathological change and EB permeability significantly decreased in intervention group compared with DM group (P < 0.05), and blank control group (P < 0.05). RT-PCR revealed that the mRNA level of VEGF, MMP-9 and Ang-1 significantly increased, and eNOS decreased in DM group compared to the normal control group (P < 0.05). The mRNA level of VEGF and iNOS decreased, eNOS increased while Ang-1 and MMP-9 had not changed in DM-blank control group and DM-intervention group compared with DM group (P < 0.05). ConclusionsIL10 modified EPC can improve the inflammative microenvironment and suppressed the pathogenesis of DR. Furthermore, EPC transplantation can increase the number of EPC and exerted their effect.
OBJECTIVE To explore the possible mechanisms of skin regeneration through the epidermal stem cells stimulated by epidermal growth factor (EGF). METHODS At 8 and 14 days after treatment with EGF, the tissue specimens from 8 skin ulcered patients who were treated with EGF were used to evaluate the distribution and differentiation of epidermal stem cells. The expression of beta 1 integrin, keratin 19 (K19), keratin 14(K14) and keratin 10 (K10) in skin was detected with SP immunohistochemical methods. Hematoxylin and eosin staining method were used to observe the tissue structure. Another 7 biopsies from ulcered patients without EGF management were used as the control. RESULTS The results from the hematoxylin and eosin staining showed that the epidermis in EGF treated wounds was thick and the epidermal ridges were enlarged both in 8 and 14 days compared with those in control skin. Immunohistochemical staining from beta 1 integrin and K 19 showed that all tissues treated with EGF were rich in epidermal stem cells both in 8 and 14 days. These stem cells were bigger in size and larger in number and localized at the base of the epidermis. In contrast, the positive expression cells of beta 1 integrin and K 19 in control group in the same time were scanty. It was found that there were some stem cell islands in epidermis treated with EGF in day 14 and absent from the control group. The expression of K14 and K10 could be observed in those terminally differentiating epidermal cells in both groups. CONCLUSION The results indicate that the possible mechanisms of skin regeneration stimulated by EGF comes from the mitogenic effects and differentiation of skin stem cells.
Objective To investigate the experimental condition and mechanism of differentiation of human umbilical cord blood derived mesenchymal stem cells（hUCB-MSC）into neuron-like cells induced by recombined human epidermal growth factor （rhEGF） and taurine in vitro.Methods hUCB-MSC were primary cultured in Dulbeccoprime;s modified Eagle's medium/F12 （DMEM/F-12）which supplemented with 105U/L penicillin G, 100 mg/L streptomycin sulfate, 10% fetal bovine serum (FBS),5% autologous plasma,4 mmol Lglutamine, 30 ng/ml rhEGF.The DMEM/F-12 medium was replaced by taurine medium after 3 passages.The expression of surface antigen CD90,CD29,CD34,CD44 and CD45 were detected by flow cytometry；the expression of neuron specific enolase,rhodopsin and nestin were investigated by immunocytochemistry. The statistical method was chi square test.Results Morphologically similar to bonemarrow MSC,hUCB-MSC became attached cells after the first 5 to 7 days in culture，and reached 80% to 90% confluent after 3 to 4 weeks. Growth accelerated after passage. hUCB-MSC were positive for CD29,CD44 and CD90 but negative for CD34 and CD45. After taurine induction, 2515/3120 cells expressed NSE, 1168/3175 cells expressed rhodopsin and 903/3050 cells expressed nestin while only 234/2965 cells expressed NSE in the control group(P＜0.01).Conclusion rhEGF and taurine can induce hUCB-MSC differentiating into neuronlike or rhodopsin positive cells.