This review describes the application of stem cells.Stem cells have proliferating and (multipotential) differentiation properties.Stem cells play an important role in the repair tissue and organs.

Neuralstemcells (NSCs)maintainthepotentialofproliferationanddifferentiationin nervesystem .TheresearchandapplicationofNSCshavedevelopedintoafrontierofneuroscienceinrecent years .Thisreviewdescribesthespecificity ,contribution ,regulationmechanismandapplicationofNSCs . Neuralstemcellsplayanimportantroleinthenervoussystemofgrowthandreparation . [

Objective Duchenne muscular dystrophy (DMD) is a lethal inherited disorder; the main pathogenesis is deficiency of dystrophin Our study is to observe dystrophin expression in myofibers of mdx mice (an animal model of DMD) transplanted with different bone marrow cells Methods Bone marrow cells, suspension cells and stromal cells were cultured in vitro from C57BL male mice, and these cells were transplanted respectively by tail vein of irradiated mdx mice Dystrophin expression of female mdx mice was detected dynamically By using PCR technique, Y chromosome specific sex determining regions were detected dynamically with the blood of transplanted female mdx mice Results Few dystrophin expression in myofibers (

【Objective】 To investigate the molecular basis of hepatolenticular degeneration (Wilson disease, WD) and to attempt to construct the feasibility of gene diagnosis in the disease. 【Methods】 We have performed the molecular biological study on this disease for 10 years by molecular geneti c techniques. 【Results】 ①Location of WD gene in Ch inese: Using pairwise linkage analysis and multipoint linkage analysis method, w e constructed a genetic map of DNA markers within D13q14.2-3 which refined the location of WD gene by restriction fragment length polymorphism(RFL P) and microsatellite polymorphism analysis; ②Screen for mutations of WD gene in Chinese people: we detected the structure of 21 exons of WD ge ne in 45 patients from 39 pedigrees by PCR-SSCP(Single strand conformation poly morphism) and PCR-DNA sequencing technology, found a new mutation in exon 5 and nuclcotide sequence analysis showed it is a T insertion. We also conformed the Arg778Leu in exon 8, the highest frequence mutation point in Chinese people, wit h mutation rate 22.8% in total;③Carrier detection and presymptomatic diagnosi s of WD: Based on DNA recombination technology, we peformed successfully the gen e diagnosis in all individuals of 79 families with WD and built up a helpful spe cific enzyme cut method (PCR-Msp1) to detect the carrier and presympomatic patients in Chinese pe ople with WD. 【Conclusion】 These results showed that the location of WD gene within D13q14.2-3 is the same in Chinese as in Caucasians, but the g ene high m utation point,the gene diagnosis method and its pathogenesis are markly different.

BACKGROUND: Causes of Parkinson disease have not been mentioned clearly up to now yet. Theory of hereditary susceptibility is the main theory to explain Parkinson disease now. But there is no definite conclusion on which hereditary factors have relationship with it.OBJECTIVE: To study the relationship between gene polymorphism caused by point mutation C to T on cDNA609 basic group of reduced NAD(P) H:quinone oxidoreductase(NQO1) gene and hereditary susceptibility of Parkinson disease.DESIGN: A non-randomized synchronized control research based on patient and healthy people.SETTING: Neurology departments in two university hospitals and a senile disease research institute in a university hospital.PARTICIPANTS: Totally 126 patients(Parkinson disease group) diagnosed as Parkinson disease in Neurology Clinic of First Hospital Affiliated to Sun Yat-sen University from September 1994 to September 1997, aged 46 to 73 years, in which 74 were males and 52 were females. Totally 136 healthy adults (control group), in which 66 were males and 70 were females, who came to the clinic to do health examination at the same time, aged 40 to 72 years.METHODS: Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) was used to analyze NQO1 gene polymorphism in Parkinson disease group and healthy adult control group.MAIN OUTCOME MEASURES: Mutation frequency and genotype of point mutation of basic group C to T on NQO1 gene cDNA609.RESULTS: T allele frequency in Parkinson disease group was 52% and that in control group was 43%. There was significant difference between two groups (P ＜ 0. 005) . There was significant difference on distribution of genotype in Parkinson disease group and control group( P ＜ 0.05). The risk incidence increased 3.8 times in individual with T allele.CONCLUSION: NQO1 gene cDNA609 mutation T allele may be a risk factor to Parkinson disease, which could be associated with the hereditary susceptibility of Parkinson disease.

Objective To investigate the MRI findings of the breast fibroadenoma which has a washout type of time signal intensity curve (TIC)for the purpose of improving imaging diagnosis.Methods The MRI findings of 20 cases of the breast fibroadenoma with a washout TIC and 20 cases of breast carcinoma verified by histopathology were analyzed retrospectively.Morphological features,internal signal, ADC value and dynamic enhancement performance of the two groups were compared with each other.Results The shapes of the breast fibroadenomas were more commonly ovoid or round (18/20),and the margins were circumscribed(16/20),Most of the fibroadenomas were high intensity in T2 WI with the non-contrast enhanced separations (9/20).The average minimum ADC value was (1.412±0.332)×10-3 mm2/s,and higher than that of breast cancer (0.888 ±0.1 60)×10 -3 mm2/s with the significant difference (P <0.05).Enhancement scanning showed relatively homogeneous enhancement (16/20).The early enhancement ratio of the breast fibroadenoma was (1.694±0.628)×100% on average,and lower than that of breast cancer (1.849 ±0.430)× 100%.The difference was no statistical significance(P >0.05 ). Conclusion The breast fibroadenoma with washout TIC has a similar performance with the breast cancer in TIC and the early enhancement rate, however,the clear edge,higher T2 WI signal intensity,the non-contrast enhanced internal separations and higher ADC values are helpful to the diagnosis of breast fibroadenoma with washout TIC.

AIM: To observe the effects of overload exercise on skeletal muscles in X-linked muscular dystrophy(mdx) mice.METHODS: Mdx mice and C57 mice were carried out swimming and hanging tail movement tests (mdx mice as control did not exercise). It lasted for 13 minutes each time per day, and lasted 3 days. Evans blue was injected into tail vain. The mice were killed the next day, and the hind limbs were taken photographs after skins were flayed. The gastrocnemius muscles and diaphragms cryostat sections were made. Under a fluorescence microscope, Evans blue staining was seen. Then the sections were tested by routine HE staining, the histological change of muscles was analyzed under a light microscope.RESULTS: Many blue colored longitudinal lines were observed in skeletal muscles of mdx mice, whereas they were hardly seen in control mdx and C57 mice. Under a fluorescence microscope, some muscle fibers of mdx mice were stained with Evans blue, few muscle fibers of control mdx mice were stained, and C57 mice were not. Under a light microscope, HE staining of muscles showed some degenerated muscle fibers became round in shape and the myonuclei became condensed, or necrotic fibers had amorphous structures, most of them in the degenerated and necrotic fibers of diaphragms C57 mice did not have these changes.CONCLUSION: Overload exercise did harm to skeletal muscles of mdx mice; Vital staining with Evans blue is useful not only for distinguishing degenerating muscle fibers, but also for studying the degeneration process in dystrophin-deficient muscle.

Objective To investigate the effect of leptin on transcription factor nuclear-κB (NF-κB) activity of pancreatic tissue and blood inflammatory cytokines (TNF-α,IL-1β) in severe acute pancreatitis. Methods Thirty-six rats were randomly divided into three groups, including sham group (group A, n = 12), AP model group(group B, n = 12) and Leptin treatment group (group C, n = 12). SAP was induced by intraductal injection of 5% sodium taurocholate into the pancreatic duct. Exogenous leptin was injected I. P. Fifteen minutes later. The concentration of serum amylase, leptin, TNF-α, IL-1βwere measured by radioimmunoassay 6 hours later. NF-κB activity of the pancreatic tissue were measured by immunohistochemistry. The changes of pathology of the pancreas were observed. Results The levels of serum amylase, cytokine TNF-αand IL-1βwere significantly reduced in group C, and the levels of serum leptin were significantly increased in group C. NF-κB activity in the pancreatic tissue in group B were significantly higher than that in group A. However, NF-κB activity of the pancreatic tissue in group C were significantly lower than that in group B. Furthermore, the extent of necrosis of the pancreatic tissue was re-lieved. Conclusion Exogenous leptin protected the rats pancreas against damage by sodium taurocholate. The protective effects of exoge-nous leptin were attributive to the reduction in cytokines TNF-α, IL-1β. The possible protective mechanism was that leptin decreased NF-κB activity.

AIM: To observe skeletal muscle damage of mdx mice after overload exercise, and protection to muscle damage induced by exercise due to myoblast transplantation (MTT). METHODS: Muscle samples of C 57 mice were minced and digested with trypsin, and myoblasts were cultured ex vivo , purified and detected by immunohistochemistry stains. The myoblasts were injected into muscle of left limb of mdx mice, whereas the right limb was injected with DMEM liquid as control. Mice were submitted to exercise for 3 days starting 1 month after MTT, and then Evans blue was injected intravenously through the tail vein. The muscle cryostat sections of mdx mice were made, and then detected the immunofluorescence of dystrophin. Under a fluorescence microscope, the number of fiber stained with Evans blue and dystrophin was counted, analyzed quantitatively with image software. RESULTS: Under a fluorescence microscope, only 10 37%?2 87% muscle fibers in the myoblast grafted muscles were stained with Evans blue. In contrast, 26 82%?14 85% muscle fibers in right control muscles were stained. Significant differences between these two groups were showed ( P

Objective To study the scientificity and rationality in data management of the project of Chinese Chronic Disease Clinical Research System and its Achievements Application Mode;To provide evidence and reference for the improvement of follow-up work. Methods According to the relevant management regulations, guidelines, and other relevant documents of national and international clinical research data,“Questionnaire for Research Data Management Assessment of Chinese Chronic Disease Prevention” was designed. The questionnaires were used in 10 clinical topics during the on-site inspection survey, and 20 valid questionnaires were retrieved and analyzed statistically. Results 50-60 percentage of subjects in data management and statistics were performed by the third party;70 percentage of subjects were performed by their own central monitoring;50 percentage of the subjects adopted a cooperative manner with others to develop appropriate data management systems;7 centers had system and plan for data management;Data management was carried out;implementation degree of training, database, CRF tracing, and others 7 aspects was low. Conclusion Improving the quality of data management of TCM clinical research still needs to be perfected from many aspects, and quality mode of large-scale clinical trials should be improved.