Changes in the biological behaviors of colon cancer cells under simulated hypoxia in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the reactivity of colon cancer cell line SW480 and CD133(+) SW480 subsets to hypoxia in vitro and the changes in the expressions of anti-apoptosis and angiogenesis genes.</p><p><b>METHODS</b>SW480 cells was subjected to CoCl(2) exposure at varying concentrations and for different time lengths to induce hypoxia, and the protein expression of hypoxia induced factor 1α (HIF-1α) was detected by Western blotting. The CD133(+) SW480 cells were sorted by magnetic activated cell sorting (MACS) and their proportion was assayed by flow cytometry (FCM). The CD133(+) SW480 subsets were exposed to CoCl(2) at the optimal concentration with exposure time selected in terms of HIF-1α level, and their tumor stem cell sphere formation ability was evaluated. Real-time PCR was used to compare the mRNA expression levels of the surface markers of colon cancer stem cells (CD133 and PROM1), survivin, and vascular endothelial growth factor (VEGF).</p><p><b>RESULTS</b>Exposure to 200 µmol/L CoCl(2) for 8 h resulted in the highest HIF-1α expression in SW480 cells, but the same exposure failed to induce HIF-1α expression in CD133(+) SW480 subsets. The CD133(+) SW480 subsets, after CoCl(2)-induced hypoxia, showed significantly enhanced ability of cell sphere formation. Hypoxia of SW480 cells caused significant increases in CD133, survivin and VEGF mRNA levels by 1.607∓0.103, 2.745∓0.370 and 3.798∓0.091 folds, respectively (P<0.05).</p><p><b>CONCLUSION</b>CoCl(2) can simulate hypoxia in colon cancer cells in vitro to induce stable HIF-1α expression, which is concentration- and time-dependent. The hypoxia-stimulated tumor stem sells show an enhanced sphere formation and anti-apoptotic and anti-angiogenic abilities.</p>

Value of deep small-bowel endoscopy in the diagnosis of Crohn's disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the value of deep small-bowel endoscopy (DSBE) in the diagnosis of Crohns disease (CD).</p><p><b>METHODS</b>The endoscopic and clinical data of 54 patients with CD receiving capsule endoscopy (CE) and double-balloon enteroscopy (DBE) between January, 2004 and December, 2008 were summarized and analyzed retrospectively.</p><p><b>RESULTS</b>The main indications for DSBE in our series were suspected CD (42.6%) and obscure gastrointestinal bleeding (25.9%). DSBE was obviously superior to barium imaging. The detection rate of CD was significantly higher with DSBE (92.6%) than with ileocolonoscopy (75.9%, P=0.017), and DSBE provides much more detailed descriptions of specific endoscopic features such as segmental distribution and lumen changes. DSBE significantly improve the diagnostic efficiency, giving priority to offer a guide and raise suspected diagnosis for CD.</p><p><b>CONCLUSION</b>DSBE is a valuable modality for detecting CD lesions in the jejunum and ileum and for evaluating lesion involvement and severity. The combination with a comprehensive analysis of routine imaging findings, gastro endoscopy, and clinical data can further enhance the diagnostic efficiency of DSBE.</p>

In vivo cardiac magnetic resonance imaging of superparamagnetic iron oxides-labeled mesenchymal stem cells in swines / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the feasibility of magnetic resonance imaging (MR) on detecting transplanted nanometer small superparamagnetic iron oxides (SPIO) labeled mesenchymal stem cells (MSCs) in swine model with acute myocardial infarction (MI).</p><p><b>METHODS</b>MSCs isolated from swine were incubated with nanometer SPIO for 24 hours and the third-passage MSCs were labeled with DNA dye 4'-6-diamidino-2-phenylindole (DAPI) and aliphatic red fluorescent dye PKH(26)-GL. Presence of small particles of SPIO in MSCs was assessed by Prussian Blue staining and electron microscopy. Three animals in each group received SPIO-labeled MSCs (5 x 10(5); 1 x 10(6); 2 x 10(6)) and MSCs without SPIO (1 x 10(6)) injections into the infarcted myocardium approximately 1 hour following left anterior descending coronary artery. MRI (1.5-T) was performed 20 to 24 hours post infarction in all animals and the animals were subsequently sacrificed for histology 1 hour post MRI.</p><p><b>RESULTS</b>In vitro Prussian Blue staining and electron microscopy examination revealed numerous iron particles in the cytoplasm of MSCs. Low signal intensity spots with the scanning T(2)(*)WI-Flash 2d sequence were detected in all SPIO-MSCs but not in SPIO-negative-MSCs injected myocardial sites in vivo with the clinical 1.5 T scanner. Prussian blue, DAPI and PKH(26) positive cells were detected histologically in sections corresponding to low signal intensity spots area shown on MRI.</p><p><b>CONCLUSION</b>Magnetically labeled MSCs transplanted in myocardial ischemia area of swine can be visualized in vivo with a clinical 1.5-T MRI and could be used for tracking SPIO-MSCs clinically.</p>

Transplantation of autologous bone marrow mononuclear cells on patients with idiopathic dilated cardiomyopathy: early results on effect and security / 中华心血管病杂志

<p><b>OBJECTIVE</b>The aim of this study is to identify short-term result of cell transplantation in idiopathic dilated cardiomyopathy (IDC) patients who were treated by intracoronary transplantation of autologous mononuclear bone marrow cells (BMCs) in addition to standard therapy.</p><p><b>METHODS</b>Based on given standard therapy, eighteen patients with idiopathic dilated cardiomyopathy were enrolled and divided into transplantation group and control group. The clinical characteristics of two groups were comparable. Among these patients, 10 patients were performed percutaneous coronary autologous BMCs transplantation. Blood routine test, hepatic function, renal function, glucose, triglyceride (TG), cholesterol, low density cholesterol (LDL), high density cholesterol (HDL), uric acid (UA) and high sensitive C-reactive protein (hsCRP) were measured at the time point of pre-operation and some time after transplantation. All patients were monitored under ultrasonic cardiography, Holter, six-minute-walk test and magnetic resonance imaging over a period of at least 6 months. Annual hospital days were recorded during two-year follow-up.</p><p><b>RESULTS</b>Blood routine test, hepatic function, renal function, glucose, TG, cholesterol, LDL, HDL, UA and hsCRP had no significant differences among 48 hours, 3 months and 6 months after transplantation compared with control and pre-transplantation (P > 0.05). Six-minute-walk distance elevated significantly six months after BMCs transplantation compared with control and pre-transplantation [(494.3 +/- 62.8) m vs (307.2 +/- 75.0) m, (321.5 +/- 63.7) m, P < 0.05]. Left ventricular ejection fraction (LVEF) and the sizes of LVEDd had no significant changes compared with that of control and pre-transplantation (P > 0.05). Myocardium lesion area measured by (MRI) seemed decrease in transplantation group compared with that of control and pre-operation [(4.96 +/- 0.47) cm(2) vs (5.12 +/- 0.54) cm(2), (5.02 +/- 0.39) cm(2), P > 0.05], but there was no significance. None of proarrhythmias and side effects had been observed around transplantation and 2 years follow-up. There was no significant difference in survival between two groups in 2 years follow-up. Interestingly, annual hospital day in BMCs transplantation patients was significantly shorter than that in control group [(30.2 +/- 11.2) d vs (43.6 +/- 9.8) d, P < 0.05].</p><p><b>CONCLUSIONS</b>Autologous bone marrow mononuclear cells transplantation can prolong six-minute-walk, decrease re-hospitalization rate, elevate exercise ability and help to improve cardiac function in patients with IDC. In addition, it was demonstrated that cell transplantation is safe.</p>

Observation on the safety: clinical trail on intracoronary autologous bone marrow mononuclear cells transplantation for acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the safety of autologous bone marrow mononuclear cell (BM-MNCs) transplantation by intracoronary infusion in patients with acute myocardial infarction (AMI).</p><p><b>METHODS</b>One hundred and eighty-four patients with AMI treated with percutaneous coronary intervention (PCI) were randomized in a 1:1 way to either intracoronary transplantation of autologous BM-MNCs (n = 92) right after PCI or to sodium chloride concluding heparin (controlled, n = 92) via a micro infusion catheter. In the process of the intracoronary infusion of BM-MNCs, the complications should be recorded, which were aberration reflect (including of pale, syncope, nausea, hypotension and shock), deterioration of angina or heart failure, arrhythmias (including of bradycardia, sinus arrest or atrial ventricular block or ventricular fibrillation), embolism etc. Body temperature, blood pressure and heart rates should be monitored during the first week after transplantation. Holter, coronary angiography and ultrasonic cardiography were performed at the designed time points. Main heart accidents, restenosis and tumor were recorded during 2-years follow up.</p><p><b>RESULTS</b>During the period of bone marrow puncture and intracoronary infusion of BM-MNCs, few patients occurred pale, dizziness, bradycardia and hypotension, which were transient and due to vagus reflect. No stem cell-related arrhythmias, deterioration of angina were noted. In BM-MNCs group one patient developed in-stent reocclusion in one week after transplantation, five developed in-stent restenosis during further follow-up 30 months, which were similar with control group. There were no deaths, major adverse cardiac events, tumor and other late adverse events during follow-up period in both groups.</p><p><b>CONCLUSION</b>Intracoronary transplantation of autologous BM-MNCs in the acute phase after AMI is feasible and seems safe in the 30 months of follow-up.</p>

The role of first pass and delayed contrast-enhancement magnetic resonance imaging in patients with myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the role of contrast-enhancement magnetic resonance imaging (CeMRI) in patients with myocardial infarction (MI).</p><p><b>METHODS</b>There were twenty-three patients enrolled in this study. After dynamic observation, there were 20 patients who were diagnosed as MI. All those patients underwent coronary artery angiography and CeMRI. MRI was performed with a 1.5-T magnet (AVANTO, SIMENS). After tagged images were acquired, the patients received an intravenous bolus of 0.1 mmol/kg Gd-DTPA at a rate of 5 ml/s. A first-pass perfusion scan was acquired simultaneously with a bolus injection. A second bolus of 0.3 mmol/kg Gd-DTPA was given following the first-pass images. Delayed images were acquired 5 minutes after the second bolus by using an inversion-recovery prepared gated fast-gradient echo-pulse sequence.</p><p><b>RESULTS</b>Hypoenhancement was seen in 20 patients at the first-pass perfusion at the myocardial infarction site, while hyperenhancement was seen at delayed CeMRI. Myocardial infarction area in delayed CeMRI was 16.58% +/- 9.73%, which was correlated positively with peak CK and cTnT (r = 0.821, P < 0.01 and r = 0.565, P < 0.05), respectively. The ejection fraction (EF) detected by MRI was 0.46 +/- 0.13, while the left ventricular EF (LVEF) detected by left ventriculography was 0.49 +/- 0.16. There was no difference between two parameters.</p><p><b>CONCLUSIONS</b>CeMRI may play an important role in the diagnosis and prognosis of patients with MI.</p>

In vitro and in vivo MR imaging of SHU 555A-labelled swine bone marrow mesenchymal stem cells / 介入放射学杂志

Objective To detect the feasibility of magnetically labeled swine bone marrow mesenehymal stem cells(MSCs)with SHU 555A combined with poly-L-arginine(PLL),under MR imaging in vitro and in vivo.Methods Swine mesenehymal stem cells were isolated and culture-expanded 3 passages in vitro,then magnetically labeled by incubation with SHU 555A(25?g Fe/ml,Resovist,Schering)for 24 hours with 750 ng/mL poly-L-lysine(PLL;average MW_275 kDa)added 1 hour before incubation.Cellular iron incorporation and detention at 0 d,4 d,8 d,12 d,16 d,20 d after labeling was qualitatively assessed using Prussian blue and quantified at atomic absorption spectrometry.Cell viability was assessed by trypan-blue exclusion test.Cell suspensions underwent MR imaging with T_1-and T_2-weighted spin-echo and fast field-echo sequences on a clinical 1.5 T MR system.At last,1?10~6 SHU 555A labeled and unlabeled MSCs were transextracardially implanted into the infracted and normal myocardium approximately 2 week following the ligation of left anterior descending coronary artery in 1 swine respectively,and finally performed 1.5-T MRI within 1 week after infarction.Results①Intracytoplasmic particles stained with Prussian blue stain were detected for all cells with mean cellular iron content of(13.13?2.30)pg per cell.With division of stem cells, the stained particles decreased gradually with iron content(0.68?0.20)pg per cell.at 16 days after labeling, approximately to the prelabeled baseline values.(0.21?0.06)pg per cell(P＞0.05).The viability of the labeled cells at various time points were not significantly different with that of nonlabeled cells(P＞0.05).②MR images showed signal intensity changed most obviouly in T2*WI in vitro.The percentage change of signal intensity increased with increasing cell numbers,and decreased with the time.As few as 5?10~4-1?10~5 cells could be detected by using this approach.③Two injected sites containing MR-MSCs were detected in vivo,presentingas low signal intensity areas with the T_2*WI scanning sequence.Conclusion Swine bone marrow MSCs can be labeled with SHU555A-PLL and depicted with a standard 1.5-T MR imager in vitro and in vivo.(J lntervent Radiol,2007,16:115-121)