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 (

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.

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 investigate the diagnostic value and therapeutic implication of breast imaging reporting and data system (BI-RADS)in non-palpable breast lesions detected by imaging.Methods 21 7 patients,who were found clinical non-palpable suspi-cious lesions in breast by X-ray examination,were enrolled in our study.All patients underwent general mammography (including craniocaudal view and mediolateral oblique view)and mammographic spot view in some patients,then were biopsied using 3D wire guided location biopsy.The predictive value of BI-RADS was analyzed by compare the imaging diagnosis with pathological results. Results Of the 21 7 cases,98 cases were diagnosed of grade Ⅲ,81 cases of grade Ⅳ and 38 cases of grade Ⅴ using BI-RADS.All cases were confirmed by surgery.All lesions were excised completely according to the preoperative 3D wire guided location biopsy. 75 lesions were malignant (34.6%,75/21 7),including 39 cases of carcinoma in situ (52.0%,39/75);142 lesions were benign.1 1 cases of grade Ⅲ,29 cases of grade Ⅳ and 35 cases of grade Ⅴ were malignant.The positive predictive value of BI-RADS for gradeⅢ,grade Ⅳ and grade Ⅴ was 1 1.2% (1 1/98),35.8% (29/81)and 92.1% (35/38)respectively.The positive predictive value of BI-RADS Ⅳ for premenopausal and postmenopausal women was 24.5% (13/53)and 57.1% (1 6/28).Conclusion BI-RADS can improve the resection rate and biopsy rate of non-palpable breast lesions by 3D wire guided location biopsy,and the detection rate of early breast cancer.

Objective To study the mechanism of restenosis following percutaneous transluminal coronary angioplasty(PTCA),and to replicate a dynamic model of cell proliferation and remoulding of vascular wall at different time points in rabbits after intimal injury.Methods The model of restenosis in common carotid artery was established by balloon injury in 70 rabbits.The indexes such as lumen area,thickness and area of intima and media,and cross sectional area bounded by the external elastic lamina(EELA) were respectively measured by computer image analysis technology at the 1st,3rd,5th, 7th,14th,28th and 35th day after the injury.Results Endothelial cells were denudated at the 1st day after injury.The proliferation of vascular smooth muscle cell(VSMC) was detected on the surface of lumen at 3 days after injury.At the 7th day after injury,the neointima was formed and continuously thicken.The thickness and area of the neointima as well as extracellular matrix were gradually increased after 14 days,and were maximal after 35 days.The thickness and area of media were also gradually increased during 3～14 days and decreased after 28 days.Compared with non-injured vessel,the medial area was obviously increased at the 14th day.The lumen area was decreased at the 5th～7th day after injury and was obviously less than that of non~injured vessel after 14 days.The EELA was gradually increased at the 1st～7th day after injury,and reached its maximum at the 14th day.The EELA was declined gradually after 28 days.Conclusion The progress of restenosis(RS) can be simulated through the model of restenosis in common carotid artery of rabbit established by balloon injury.The intimal proliferation and vascular remodeling are the leading pathogenesis of restenosis.

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.

Objective To investigate the value of dynamic contrast-enhanced MRI parameters in the diagnosis of cervical squamous cell carcinoma. Methods A retrospective analysis of dynamic contrast enhanced MRI in 55 patients with pathologically diagnosed cervical squamous cell carcinoma without prior treatment. They were divided into three groups based on grade of differentiation: well differentiated ( 6 patients),moderately differentiated(28 patients)and poorly differentiated group(21 patients). Capacity volume transfer constant (Ktrans),exchange rate constant(Kep) and extravascular extracellular volume fraction (Ve) were measured in each group of patients, and comparing the correlation with ANOVA, DCE-MRI parameters and grading of squamous differentiation using Spearman rank correlation analysis. Results Ktrans of the poorly, moderately and well differentiated cervical squamous cell carcinoma were (2.42±0.58),(1.71± 0.78),(1.27±0.78)/min respectively, Kep were (4.17±1.23),(3.08±1.58),(2.55±0.87)/min respectively, Ve were 0.60 ± 0.12,0.60 ± 0.19,0.43 ± 0.17 respectively. Statistical difference of Ktransand Kep were found among the subgroups of different pathological grading.(F values were 7.518 and 4.234,P all<0.05), Ve difference was not statistically significant (F=2.382, P>0.05). Statistical difference of Ktransand Kep were seen in multiple comparisons, between the groups of poorly and moderately differentiated groups poorly and well differentiated groups (P all<0.05),difference was not statistically significant of Ktransand Kep were seen in the groups of moderately and well differentiated groups(P> 0.05). There were moderate negative correlation between Ktrans,Kep and the pathological degree (r=-0.531 and -0.446, P=0.001 and 0.002), Ve had no correlation between pathological grade (r= -0.220, P = 0.141).Conclusion DCE-MRI parameters Ktrans and Kep reveal perfusion characteristics in different pathological grades of cervical squamous cell carcinoma.

Objective:To evaluate the value of synthetic MRI combined with DWI in the diagnosis of benign and malignant breast lesions.Methods:The data of 184 consecutive patients with suspected breast lesions in Yunnan Cancer Hospital from July to September 2019 were prospectively analyzed. All patients were randomly assigned to training group ( n=110) and validation group ( n=74), and underwent conventional MRI and synthetic MRI respectively before and after contrast injection. At the maximum slice of the lesion, the ROI was drawn along the edge and recorded as "tumor". In the solid area with the most obvious tumor enhancement, the second ROI was drawn and recorded as "local". At the same time, ADC values (ADC local and ADC tumor) and relaxation time values (T local and T tumor) were measured. T and T + represented the relaxation time value of the ROI pre-and post-contrast scanning. ΔT% represented the relative change rate in T value between pre-and post-contrast scanning.The rank sum test was used to test the quantitative parameters of benign and malignant breast lesions in the training group and the validation group, and the variables with P<0.05 were included in the binary logistic regression analysis to screen the independent variables and establish the prediction model. The area under ROC curve was used to evaluate the discrimination of parameters and models. The clinical applicability of model was analyzed by decision curve analysis (DCA). Results:In the training group, univariate analysis showed that there were significant differences in T 1tumor, T 1+tumor, ΔT 1% tumor, T 2local, T 2+local, T 2tumor and T 2+tumor, ADC local, ADC tumor between benign and malignant breast lesions ( P<0.05). Multivariate logistic regression analysis showed that T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor were independent variables in the diagnosis of breast cancer. The relaxation time model (model A: T 1+tumor, ΔT 1% tumor, T 2tumor) and ADC model (model B: ADC local, ADC tumor) established by combining the above variables had the same diagnostic efficiency (AUC=0.905, 0.914, Z=-1.874, P=0.062), and the multi-parameter combination model (model C: T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor) had the highest diagnostic efficiency (AUC=0.965). DCA analysis showed that when the threshold probability ranges between 21%-99% (training cohort) and 15%-99% (validation cohort), the net benefit of model C was better than model A and B. Conclusion:The multi-parameter combined prediction model established based on the relaxation time value and ADC can identify breast cancer efficiently and can be used as an auxiliary diagnostic tool.