Cancer stem cells are a new field with the gradual deep understanding of the stem cell research.Although its history is not long,the rapid development showed a good potential prospect.The existence of cancer stem cells and its use as tumor formation,growth and metastasis-based approach has been widely recognized.In theory,cancer stem cells derived from normal stem cells can transform.Cancer-causing factors can also be derived from the dedifferentiation induced cells.Because it contains all-round,multi-and single stem cell,with the proliferation and differentiation potential of different directions,it is possible to explain the heterogeneity of tumor cells,and reasons for hypoxic environment,anti-cancer drugs and radiation resilience.In this area,it has been made a lot of progress in recent years.However,there are still some problems to be solved.Such as the identification of cancer stem cells,biological function and mechanism.

Cancer stem cells are a new field with the gradual deep understanding of the stem cell research. Although its history is not long, the rapid development showed a good potential prospect. The existence of cancer stem cells and its use as tumor formation, growth and metastasis-based approach has been widely recognized. In theory, cancer stem cells derived from normal stem cells can transform. Cancer-causing factors can also be derived-from the dedifferentiation induced cells. Because it contains all-round, multi-and single stem cell, with the proliferation and differentiation potential of different directions, it is possible to explain the heterogeneity of tumor cells, and reasons for hypoxic environment, anti-cancer drugs and radiation resilience. In this area, it has been made a lot of progress in recent years. However, there are still some problems to be solved. Such as the identification of cancer stem cells, biological function and mechanism.

Objective To investigate the normal aortic valve histological manifestation and histopathological changes of degenerative aortic valve.Methods In Tianjin Chest Hospital,there were patients due to aortic valve disease undergoing aortic valve replacement surgery in the Department of Cardiovascular Surgery,and in 22 cases,their pathological aorta tricuspid valves were successfully excised from May 2009 to May 2010.The aortic valve tissues were collected,and according to hematoxylin and eosin (HE) staining of the degenerative calcified aortic valves with stenosis,they were divided into pathological valvular calcification locus group and non calcification locus group.Six morphologically normal aortic valve tissues were taken as a control group.The situation of collagen fibers,elastic fibers and collagen content in normal and disorder valves were analyzed by using of IDA-2000 high definition color medical image analysis system.Results With the naked eye,the thickness of the valve leaves with stenosis was increased,and at the valve leaf close to the side of arota,calcified foci were produced.Under light microscope,inflammatory changes were found in the aortic valve endothelium,in the tubular wall,there were aggregations of newly formed capillary with relatively thin wall,cholesterol crystals,cells similar to foam cells and diffuse and nodular calcification commonly seen,Compared with the normal valve,the ratio between collagenous and elastic fibers no matter at calcified or non-calcified region was greater in pathological valve [(3.19-± 1.01)％,(2.62-± 0.34)％ vs.(1.89-± 0.29)％,both P ＜ 0.05],collagen content (ratio =collagen/valve area) was also higher [(65.17 ± 11.48)％,(39.25-± 11.15)％ vs.(22.99 ± 4.78)％,P ＜ 0.05] in pathological valve,and the changes in calcified region were more significant than those in non-calcified region (both P ＜ 0.05).Conclusions Proliferation of collagen and degradation of elastic fibers are obvious in degenerative aortic valve,and the changes are more prominent at calcified region.

Objective:To study the expression and clinical significance of hypoxia-inducible factor-1? (HIF-1?) in squamous cell carcinoma of buccal mucosa.Methods:45 cases of paraffin embedded samples of squamous cell carcinoma of buccal mucosa were examined with HIF-1? antibody by immunohistochemistrical method. The relationship between HIF-1? expression and clinico-pathological factors such as sex, age, duration of tumour, T classification, differentiation, lymph node metastasis in the neck, recurrence, clinic classification, tumour thickness, the number of mitosis and the degree of lymphocyte invasion was analyzed.Results:The positive expression of HIF-1? was found in 31 out of the 45 cases(69%). HIF-1? positive reaction was predominately located in the center of tumour nest. While analyzing clinico-pathological factors, only T classification (between T1+T2 and T3+T4, P=0.008), lymph node metastasis of the neck (P=0.037) and clinic classification (between stage I+II and III+IV, P=0.011) showed a significant correlation with HIF-1? expression. HIF-1? possitive expression is higher in T3+T4(d=4.87 mm) than that in T1+T2(3.81 mm) (P=0.046). Logistic analysis showed that the longer the patients lived after operation, the less the HIF-1? positive expression.Conclusions:HIF-1? positive expression in squamous cell carcinoma of the buccal mucosa correlates to T classification, lymph node metastasis of neck, clinical classification and survival

Objective To investigate the detection rate and possible factors of hyperhomocysteinemia(HHcy) in children with chronic kidney disease(CKD).Methods The clinical data of children with CKD between July 2012 and September 2016 in the Department of Pediatrics,Peking University First Hospital were retrospectively collected.The homocysteine(Hcy) level of patients were measured.The other data included the general information,diagnosis and laboratory test results.Results Seventy-six pediatric patients with CKD were enrolled including 49 boys and 27 girls.The average age of the patients was (9.9±3.4) years old.The main cause of the patients in the study was primary glomerulopathy(48.7%,37/76 cases),and the rest were congenital and inherited glomerular diseases(36.8%,28/76 cases),secondary glomerular diseases(9.2%,7/76 cases)and renal tubular diseases(5.3%,4/76 cases).Fifty patients (65.8%,50/76 cases) had normal level of Hcy which was 10.40(7.30,11.62) μmol/L.Twenty-six patients(34.2%,26/76) were detected with HHcy whose Hcy level was 17.93(16.76,24.11) μmol/L.The detection rate of HHcy in CKD stage 1,stage 2,stage 3,stage 4 and stage 5 was 13.9%(5/36 cases),22.2%(2/9 cases),50.0%(4/8 cases),57.1%(4/7 cases) and 68.8%(11/16 cases) respectively,and the detection rate increased with CKD stages and the difference was statistically significant (χ2=17.574,P<0.001).The level of Hcy was 10.05(7.04,12.47) μmol/L,11.75(10.78,16.44) μmol/L,13.73(10.09,18.23) μmol/L,15.81(11.12,20.71) μmol/L and 17.39(11.86,24.76) μmol/L in CKD stage 1,stage 2,stage 3,stage 4 and stage 5,respectively.The Kruskal-Wallis test revealed that the distribution of homocysteine in CKD stages had statistically significant difference(P=0.001).Multiple linear regression model showed that creatinine clearance was an independent predicator of HHcy.Conclusions In this study of the CKD patients,the detection rate of HHcy was high and increased with the progression of CKD.HHcy is mainly influenced by creatinine clearance in CKD.The level of Hcy should be monitored regularly in children with CKD and HHcy should be treated with proper measures.

This study was aimed to create a method for content determination of quercetin, luteolin and kaempferol in flowers of Dimocarpus longan Lour. from different habitats of Guangxi province by HPLC. The samples were sepa-rated on the Hypersil C18 column (250 mm í 4.6 mm, 5 μm) which was eluted with methanol-0.2% phosphoric acid solution (47:53) with detective wavelength at 360 nm, flow rate at 1.0 mL·min-1, and column temperature at 30℃. The results showed that this method had a good linear relationship within the range of 0.18 to 2.88 μg for quercetin, 0.059 to 0.944 μg for luteolin, and 0.024 to 0.384 μg for kaempferol (r = 0.9999). The average recovery rate was 100.06% (RSD = 1.72%), 99.77% (RSD = 1.18%) and 98.67% (RSD = 1.99%, n = 9), respectively. It was conclud-ed that this method is simple, rapid, reliable and with good repeatability, which can be used in the quality control of flowers of Dimocarpus longan Lour.

Objective To explore the repair possibilities of endothelial progenitor cells (EPCs)in peripheral blood in patients with different extents of obstructive sleep apnea (OSA) through measuring the levels of pro-angiogenic factors and different subgroups EPCs in peripheral blood in patients with OSA. Methods Ninety adult patients with OSA, 30 healthy controls with matched age and gender were enrolled for this study. The subjects performed Polysomnography, were divided in-to four group based on Apnea Hypopnea Index (AHI). The serum levels of HIF-1α, SDF-1αand VEGF were assessed by ELISA. Mononuclear cells were isolated from peripheral blood with density gradient centrifugation, and flow cytometry was used to detect levels of CD133+KDR+EPC, CD133+CD34+EPC, CD34+KDR+EPC and ALDHloCD34+KDR+EPC based on AL-DH activity, and CD133, CD34, PE-KDR related cell surface markers. Results The levels of CD133+KDR+EPC, CD133+CD34+EPC, CD34+KDR+EPC were higher in OSA groups than those of control group, both of which were higher in severe OSA group than those of in mild and moderate OSA groups. The levels of ALDHloCD34+KDR+EPC were higher in mild and moderate OSA groups than that of the control groups, and the levels of ALDHloCD34+KDR+EPC were significantly lower in se-vere OSA group than those of control, mild and moderate OSA groups. Serum levels of HIF-1α. VEGF were significantly high-er in OSA groups compared to those in control groups, both of which were higher in severe OSA group than those of mild and moderate OSA groups. Serum levels of SDF-1αwere significantly lower in severe OSA groups than those of mild, moderate OSA and control groups (P<0.05). Conclusion The mobilization and recruitment of different subtypes of EPCs are obvious-ly increased in patients with OSA, but ALDHloCD34+KDR+EPC with vascular repair capacity keeps to invariability, even de-creases in patients with severe OSA, which results in endothelial damage, and increases the risk of cardiovascular disease.

Objective: To explore the value of CYP2C19 genotype polymorphisms for guiding the strategy of anti-platelet therapy in coronary artery disease (CAD) patients after percutaneous coronary intervention (PCI) with clinical prognosis.
Methods: A total of 326 CAD patients with PCI treatment received CYP2C19 genotype examination. According to CYP2C19 polymorphisms, the patients were divided into 3 groups. The patients with CYP2C19*1/*1, fast metabolism were defined as Routine group, who received clopidogrel 75 mg/day,n=128. The patients with CYP2C19*1/*2, CYP2C19*1/*3, CYP2C19*2/*3, CYP2C19*2/*2, CYP2C19*3/*3, medium and slow metabolism were further divided into 2 groups as High clopidogrel group, who received clopidogrel 150 mg/day,n=99 and Ticagrelor group, who received ticagrelor 90 mg/bid,n=99. The changes of platelet aggregation rate (PAgT) at before and 1, 3, 6 months after PCI were observed, the major adverse cardiac events (MACE) and bleeding condition were compared among different groups at 6 months after PCI.
Results: The PAgT was similar between High clopidogrel group and Routine group at 1, 3, 6 months after PCI, P>0.05;while compared with High clopidogrel group and Routine group, the PAgT decreased in Ticagrelor group at 1, 3, 6 months after PCI,P<0.05. The occurrence of MACE was similar between High clopidogrel group and Routine group at 6 months after PCI,P>0.05; while compared with High clopidogrel group and Routine group, Ticagrelor group had much less MACE occurrence,P<0.05. Ticagrelor group had no more major bleeding events than the other 2 groups,P>0.05.
Conclusion: High dose clopidogrel does not increase MACE occurrence in CAD patients with CYP2C19 medium and slow metabolism after PCI. Ticagrelor may decrease PAgT and MACE occurrence without elevating the major bleeding events.

Objective To assess the value of magnetic source imaging (MSI) in localizing the linguistic center of auditory function of epileptic patients before operation. Methods Epileptic focus and the linguistic center of auditory function in 24 patients were localized with MSI before operation. And the relationship between epileptic focus and auditory language area was observed. Results The linguistic center of auditory function was localized in left temporal lobe in 14 patients, in right temporal lobe in 5 patients and in bilaterial temporal lobe in 5 patients. Epileptic focus was localized in left temporal lobe in 14 patients, in left temporal lobe and left parietal lobe in 1 patient, in right temporal lobe in 4 patients, in right temporal lobe and parietal lobe in 1 patient, in left frontal lobe and left temporal lobe in 1 patient, in right frontal lobe, right temporal lobe and parietal lobe in 1 patient, and in bilaterial temporal lobe in 2 patients. Epileptic focus was superimposed with the linguistic center of auditory function in 10 patients, while was not superimposed with the linguistic center of auditory function in 10 patients. The epileptic focus was localized in front of the linguistic center of auditory function in 3 patients, in behind of the linguistic center of auditory function in 1 patient. The lesion of the patient suffered from dysembryoplastic neuroepithelial tumor was not excised completely because the epileptic focus was superimposed with the linguistic center of auditory function, and the patient appeared language functional disturbance after operation in short period, remaining auditory hallucination occasionally after operation. Conclusion Epileptic focus and the linguistic center of auditory function can be localized accurately and the relationship between them can be observed clearly with MSI. MSI is useful to reduce the occurrence of language disturbance after operation.

Objective To investigate the effect of different dose of dexmedetomidine for pre-venting the visceral traction reaction during caesarean section under spinal anesthesia.Methods Two hundred ASA physical status Ⅰ-Ⅱ patients,full-term primiparas scheduled for elective cesarean sec-tion were enrolled in this randomized,placebo-controlled study.Patients were randomly allocated to receive dexmedetomidine in four groups:group C (0.9% normal saline),group D1(dexmedetomidine 0.6 μg/kg),group D2(dexmedetomidine 0.8 μg/kg),group D3 (dexmedetomidine 1.0 μg/kg),50 cases in each group.Two minutes after cutting umbilical,groups D1,D2,D3 received an intravenous infusion single-dose of 0.6,0.8,1.0 μg/kg dexmedetomidine respectively for 10 minutes.Group C was injected the same dose of saline.Maternal blood pressure (BP),heart rate (HR),Ramsay scores,visceral traction reaction conditions were recorded at three points:before iv (T0 ),10 min af-ter iv (T1 )and abdominal exploration (T2 ).Results As for the inhibition of visceral traction pain, groups D2 and D3 were obviously better than groups D1 and C,and there was no statistically signifi-cant difference between groups D2 and D3 at T2 (P <0.05 ).The effects of slowing down heart rate and increasing blood pressure were weaker in group D2 than that in group D3 at T2 .Ramsay scores were higher in groups D2 and D3 than in groups D1 and C (P <0.05),and there was no significant difference between groups D2 and D3 at T2 .Conclusion Administration of dexmedetomidine 0.8 μg/kg could alleviate the visceral traction reaction and had little effect on maternal hemodynamics.