Objective To investigate the feasibility of differentiating human umbilical cord blood stem cells into hepatocytes. Methods Thirty-six BALB/c nude mice were randomly divided into experimental group and control group(18 in each of the group), and experimental group was again randomly divided into group A， B and C (six in each of the group). The mice in experimental group and control group were exposed to 350 cGy radiation produced by 60Ｃｏ. After 3 h, karyocytes at different concentrations in the fresh human umbilical cord blood were injected into the mice in experimental group A, B, C via their tail veins, and the equal volume of normal sodium (NS) was also injected into control group via tail veins. After one month, carbon tetrachloride (CCl4) was injected into experimental group A, B and control group via abdominal cavity, and the equal volume of normal sodium was injected into experimental group C. After two months, immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect the expressions of human cytokeratin-18 (CK18), cytokeratin-19 (CK19) and albumin (ALB) in liver tissues of all mice. Results The expressions of CK18, CK19 and ALB in injured liver tissues were all positive, and the expressions of experimental group B were higher than those of experimental group A （P＜0.05）, but the expressions of CK18, CK19 and ALB in the liver tissues of control group and experimental group C, whose were not injured with CCl4, were all negative. Conclusion Human umbilical cord blood-derived stem cells can differentiate into hepatocytes and express ALB under special microenvironment after liver injured by CCl4 , and the expression level of ALB maybe directly related to the number of human umbilical cord blood stem cells.
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 application advancements of ATP-binding cassette (ABC) transporter in medical research.Methods Relevant literatures about the applications of ABC families in medical research were reviewed. Results ABC families mainly took roles in transporting substances across cell membrane. Some of them were useful for the prediction of drug resistance and the prognosis of malignant tumors. Others were target s for molecular researches. Their expressions or mutations might be related with the occurrence of diseases. Conclusion ABC families are very important in the diagnosis and therapy for diseases. Thus they are very promising tools for future medical research.
Purpose To investigate the characteristics of intraocular growth of mice embryonic stem cells (ESC) in nude mice. Methods The undifferentiated murine ESC in vitro were transplanted into the eyes of nude mice.Mophological and immunohistochemical examinations were implemented. Results Two to three days after transplantation,yellowish-white granules and masses were seen inside the anterior chamber and vitreous cavity and enlarged gradually.Morphological examination showed that there were undifferentiated cells and differentiated cells in anterior chamber and vitreous cavity.The morphology and alignment of some differentiated cells were similar to those of the retina of nude mice.The cells were highly positive in NSE staining. Conclusion The transplanted ESC could grow in the eyes of nude mice and differentiate into neurons and retina-like structure. (Chin J Ocul Fundus Dis，2000，16：213-284)
Duchenne muscular dystrophy is an X-linked inherited progressive degenerative muscle disease caused by mutations in the dystrophin gene, and is one of the most common progressive muscular dystrophies. We will review the selection of genetic diagnosis methods for Duchenne muscular dystrophy, the selection of experimental animal models, and treatment for the primary cause (including gene replacement therapy, exon skipping therapy, genome editing, stop codon read-through therapy, and stem cell therapy), the treatment of secondary pathological reactions and methods of assessing disease progression. The purpose is to enrich clinicians’ knowledge of the disease and provide a reference and help for the clinical diagnosis and treatment of Duchenne muscular dystrophy.
Objective To discuss the changes of c-kit/scf mRNA and protein in guinea pig gallbladder fed on high cholesterol diet. Methods Twenty guinea pigs were divided into two equal groups of 10 each：the control group and lithogenic group. Normal diet and high cholesterol diet was given to each group respectively. The period of stone permeation was six weeks. RT-PCR and Western blot were used to determin the expressions of c-kit and scf mRNA and protein. Results RT-PCR results showed that the expressions of c-kit mRNA（t=6.985，P＜0.01） and scf mRNA （t=6.028， P＜0.01）decreased significantly in lithogenic group compared with the control group. Western blot results showed that the expressions of c-kit protein （t=10.256， P＜0.01） and scf protein （t=9.586， P＜0.01）decreased significantly in lithogenic group compared with the control group. Conclusions The expressions of c-kit/scf mRNA and protein decrease during the formation of cholesterol gallstones in guinea pigs fed on high cholesterol diet. Inhibition of c-kit/scf pathway may play a role in the formation of cholesterol gallstones.
Objective To investigate the viability and the characters of proliferation and differentiation of retinal stem cells (RSCs) after cryopreservation and anabiosis. Methods The RSCs of a Long Evans rat with the embryonic age of 17 days were separated and cultured in vitro. The third-passage RSCs in the cryopreservation liquid consisted of 80% Dulbecco modified Eagle medium (DMEM)/F12，10% bovine serum albumin (BSA)，10% dimethylsulfoxide (DMSO)，and basic fibroblast growth factor (bFGF) (20 ng/ml), were stored in liquid nitrogen. After 1, 2, 4, 8, 12, and 16 weeks of freezing period, these cells were thawed. The livability of the cells was counted and the differentiation was induced while the proliferation and characters of differentiation were detected by immunofluorescence. Results The effects of different durations of cryopreservation on the livability of RSCs did not differs much (Pgt;0.05). These cells were reculturd well and presented specific marker of RSCs. In addition, they also could be induced and differentiated into several types of retinal cells. Conclusion Cryopreservation and anabiosis of RSCs does not affect the cellular intrinsic characters of proliferation and differentiation. (Chin J Ocul Fundus Dis, 2007, 23: 94-97)
ObjectiveTo review the role of stem cell niches in maintaining cardiac stem cells homeostasis, and to foresee its prospects. MethodsThe literature on cardiac stem cells niches was extensively reviewed. The roles of stem cell niches components, extracellular matrix, and secretory factors in maintaining cardiac stem cell homeostasis were analysed and reviewed. ResultsLots of experiments reveal that stem cell niches are able to delay the aging of cardiac stem cells, protect from external damage, keep stem properties, and improve the purity and quantity. However, the mechanism is not fully understood. ConclusionThe stem cell niches have a very bright application prospect in homeostasis, purification, and amplification for the cardiac stem cells, and it needs further study.
【Abstract】 Objective To review the progress and cl inical appl ication of cellular therapy for stress urinaryincontinence (SUI). Methods The l iterature about cellular therapy of SUI was extensively reviewed. Results Becauseof having no or poor regeneration capacity, the cl inical application of chondrocytes and myoblasts were l imited. Based on the rapid progress in stem cell biology, an increasing number of animal experiments and cl inical trials about cellular therapy of SUI have been reported with encouraging results. All these show that cellular therapy has great potential in cl inical application. Stem cells are considered as ideal seeded-cells for treatment of SUI. Conclusion Cellular therapy, especially stem cells, provides a novel approach for treatment of SUI, but the mechanism needs further study.
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．