Effect of implantation of cardiosphere-derived cells combined with rat heart tissue-derived extracellular matrix on acute myocardial infarction in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate whether heart tissue-derived extracellular matrix (ECM) promotes the differentiation of cardiosphere-derived cells (CDCs) implanted in rat infracted myocardium to improve the cardiac structure and function.</p><p><b>METHODS</b>Rat CDCs were cultured by cardiac explant methods, and ECM was prepared by decelluariztion method. In a Wistar rat model of acute myocardial infarction established by ligating the left anterior descending branch, IMDM solution, ECM suspension, 10CDCs in IMDM solution, or 10CDCs in ECM suspension were injected into the infracted rat myocardium (6 rats in each group). The cardiac function of the rats was evaluated by cardiac ultrasonography, and the percentage of positive heart fibrosis area after infarction was determined with Masson staining. The differentiation of implanted CDCs in the infarcted myocardium was detected using immunofluorescence assay for the markers of cardiac muscle cells (α-SA), vascular endothelial cells (vWF) and smooth muscle cells (α-SMA).</p><p><b>RESULTS</b>Three weeks after acute myocardial infarction, the rats with injection of CDCs in ECM showed the highest left ventricular ejection fraction (LVEF) and percentage of fraction shortening with the lowest percentage of positive heart fibrosis area; implantation of CDCs with ECM resulted in significantly higher rates of CDC differentiation into cardiac muscle cells, vascular endothelial cells and smooth muscle cell (P<0.05).</p><p><b>CONCLUSION</b>Heart-tissue derived ECM significantly promotes the differentiation of CDCs implanted in the infracted myocardium into cardiac muscle cells, vascular endothelial cells and smooth muscle cells to improve the cardiac structure and cardiac functions in rats.</p>

Effect and mechanism of panaxoside Rg1 on neovascularization in myocardial infarction rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects and mechanisms of panaxoside Rg1 on the new vessel formation in acute myocardial infarction (AMI) rats.</p><p><b>METHODS</b>The AMI model of male Sprague-Dawley (SD) rats was established, and rats were randomly divided into the AMI model group, the treatment group of panaxoside Rg1, the placebo group and the treatment group of panaxoside Rg1 plus rapamycin. Cardiac creatases were determined with 1 mL blood drawn from vena caudalis of the rats 48 h after the model was successfully made. After 4 weeks, Evans blue was injected into the aorta roots of the rats, and then, red tetrazoline was dyed again and the myocardial infarction area was evaluated. The microvessel density (MVD) of infarction area was determined by the immunohistochemistry of CD31; enzyme-linked immunosorbent assay (ELISA) was used to detect the protein content of CD31 and hypoxia inducible factor-1alpha (HIF-1alpha) of the infarction area.</p><p><b>RESULTS</b>The MVD in the infarction area and the contents of CD31 and HIF-1alpha in the Rg1 treatment group were higher than those in the AMI model group significantly (P<0.05). The cardiac creatase and infarction area were lower in the Rg1 treatment group than those in the AMI model group significantly (P<0.05). The above effects, however, disappeared when rapamycin, the antagonist of mammalian target of rapamycin (mTOR), was administered simultaneously.</p><p><b>CONCLUSIONS</b>Panaxoside Rg1 could increase the expression of HIF-1alpha and CD31 of myocardium and stimulate the angiogenesis. The above mentioned role of panaxoside Rg1 might be related to the excitation of mTOR receptor.</p>

Prognosis of different operative procedures of coronary artery bypass grafting in the senile patients / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate myocardial protection and prognosis of the different operative procedures of coronary artery bypass grafting (CABG) for the senile patients with coronary artery disease.</p><p><b>METHODS</b>From July 2008 to June 2009, 125 cases (age ≥ 65 years old) underwent CABG were divided into 3 groups.Group A (70 cases) undertook off-pump CABG, group B (33 cases) undertook on-pump beating heart CABG. group C (22 cases) undertook on-pump CABG with cardiac arrest. Serum level of cardiac troponin I (cTnI) and creatine kinase MB isoenzyme (CK-MB) activity were examined right before operation and 0, 24, 72 and 168 h after operation. The complications during perioperative period and the mortality were investigated.</p><p><b>RESULTS</b>No significant difference was found in the right before operation and 168 h after operation of the serum level of cTnI and CK-MB in the 3 groups (P > 0.05). The serum level of cTnI and CK-MB activity of group A was the lowest and group B was lower than group C. Group A was the best concerning the complications during perioperative period. The mortality of group A was lower than group B but no significant difference was found in the mortality between group A and C. No significant difference was found in the complications during perioperative period and the mortality between group B and C.</p><p><b>CONCLUSION</b>Off-pump CABG could reduce myocardial injury and the complications during perioperative period in the senile patients.</p>

Diagnosis and therapy of primary malignant tumors of the heart and pericardium / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To summarize and analyze the experience in diagnosis and treatment of primary malignant tumors of the heart and pericardium.</p><p><b>METHODS</b>The clinical data of 24 patients with malignant tumors of the heart and pericardium treated in our hospital between Jun. 1980 and Mar. 2008 were retrospectively analyzed and the related literature was reviewed.</p><p><b>RESULTS</b>All 24 patients received surgical treatment. Radical resection in 10 cases and partial resection in 6 cases were performed, and the remaining 8 patients received only surgical exploration due to unresectable tumors. One patient died of cardiopulmonary failure in early postoperative stage and all the other patients died within 4 years after operation due to recurrence or metastases.</p><p><b>CONCLUSION</b>Echocardiography, CT, MRI, 3D-CT, CT of coronary artery and cardiac angiography are helpful for the diagnosis and selection of operation mode. Histological examination is necessary for the final diagnosis. Early diagnosis and surgical resection of the tumor as complete as possible, and combination with post-operative radiotherapy and/or chemotherapy may improve the survival of the patients.</p>

Comparison of transient changes in renal function between off-pump and on-pump coronary artery bypass grafting / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Acute renal failure following coronary artery bypass grafting (CABG) surgery is associated with high morbidity and mortality. Approximately half of all patients who develop acute kidney injury (AKI) subsequently develop acute renal failure (ARF). The purpose of the study was to compare early transient changes in renal function within the first post-operative week following CABG in patients that were either off-pump or on-pump.</p><p><b>METHODS</b>Eight hundred and forty-nine consecutive patients with isolated CABG in a single institution between January 1990 and August 2006 were retrospectively analyzed, including 518 off-pump and 331 on-pump patients. A multivariate Logistic regression model was constructed to identify risk factors for the development of AKI.</p><p><b>RESULTS</b>Sixty-one off-pump patients and 63 on-pump patients developed AKI. Risk factors for the development of post-operative AKI included an ejection fraction > or =50% or < or =30%, a pulse pressure > or =60 mmHg, peripheral vascular disease, diabetes, emergent procedure, triple-vessel disease, body mass index, peri-operative and post-operative. intra-aortic balloon pumping, NYHA class III and IV, and cardiopulmonary bypass. An ejection fraction > or =50% and peri-operative and post-operative intra-aortic balloon pumping were protective (OR <1). Peak serum creatinine for post-operative AKI was noted 12 hours and 24 hours in the off-pump and on-pump patients, respectively. Serum creatinine kinetics revealed rapid recovery in the 24th to 48th hour (off-pump) and the 48th to 72nd hour (on-pump).</p><p><b>CONCLUSION</b>Renal protection strategies are indicated from general anesthesia induction until 48 and 72 hours post-operatively in off-pump and on-pump patients, respectively.</p>

Incidence and risk factors of acute kidney injury post off-pump and on-pump coronary artery bypass grafting / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the incidence and risk factors of acute kidney injury (AKI) within the first postoperative week after off-pump or on-pump coronary artery bypass (OPCAB or CCAB) surgery.</p><p><b>METHODS</b>Consecutive patients underwent CABG between January 1990 and August 2006 in our institution and had normal serum creatinine (Scr) and estimated creatinine clearance (Ccr) values before operation were retrospectively analyzed. Multivariate logistic regression analysis was performed to identify risk factors for the development of AKI defined as Scr 130 - 199 micromol/L or Ccr 30 - 60 mlxmin(-1)x1.73 m(-2).</p><p><b>RESULTS</b>Incidence of AKI was significantly higher in patients underwent CCAB compared to those underwent OPCAB (63/331 vs. 61/518, P < 0.01). Peak Scr value was seen at 12th hour post OPCAB and 24th hour post CCAB, respectively. The rapid recovering of Scr occurred between 24th hour to 48th hour in patients underwent OPCAB and 48th hour to 72th hour in patients underwent CCAB surgery. Multivariate forward stepwise logistic regression analysis showed that LVEF < 30%, pulse pressure >/= 60 mm Hg (1 mm Hg = 0.133 kPa), peripheral vascular disease, diabetes, emergent procedure, triple-vessel disease, higher body mass index (kg/m(2)), intraoperative and postoperative IABP, NYHA class III or IV and cardiopulmonary bypass were risk factors for the development of postoperative AKI following CABG, while LVEF > 50% and intraoperative and postoperative IABP were associated with lower incidence of AKI (OR < 1).</p><p><b>CONCLUSION</b>AKI is not a rare complication post OPCAB or CCAB surgery, especially in patients with reduced LVEF, increased pulse pressure, peripheral vascular disease, diabetes, emergent procedure, triple-vessel disease, higher body mass index, intraoperative and postoperative IABP.</p>

Two-way concentration-dependent effect of H2O2 on I(Kur) and I(Ca,L) in human atrial myocytes / 生理学报

It has been shown that oxidative stress correlates with atrial fibrillation (AF). The purpose of the present study was to investigate the effects of reactive oxygen species (ROS) on the electrophysiological activity of human atrial myocytes. Right atrial appendages were obtained from patients with AF (AF group, n=12) and without AF (non-AF group, n=12). Single human atrial myocytes were isolated through enzymatic dissociation with type XXIV protease and type V collagenase, then divided into three subgroups: control group (n=12), H2O2 group (0.1, 0.2, 0.5, 0.75, 1, 2, 5, 10 mumol/L, n=7 at each concentration) and vitamin C (antioxidant) group (1 mumol/L, n=7). Ultrarapid delayed rectifier K(+) current (I(Kur)), L-type calcium current (I(Ca,L)) and action potential duration (APD) were recorded by whole-cell patch clamp. In AF control group, the maximum current densities of I(Kur) and I(Ca,L) were significantly lower than that in non-AF control group (both P<0.05) and APD(90) was significantly shorter as well (P<0.05). In both non-AF and AF groups, H2O2 showed two-way concentration-dependent effect on I(Kur) and I(Ca,L). The maximum current densities of I(Kur) and I(Ca,L) was significantly increased at lower H2O2 concentration, but was decreased at higher H2O2 concentration. In non-AF group, 0.2 mumol/L H2O2 caused a peak increase in the maximum current identities of I(Kur) [(8.92+/-0.51) pA/pF, P<0.05] and I(Ca,L) [(9.32+/-0.67) pA/pF, P<0.05]. H2O2 at a concentration higher than 0.75 mumol/L decreased I(Kur) and I(Ca,L). When the H2O2 concentrations were 0.2, 1, 2, 5 and 10 mumol/L, APD(90) was significantly shorter compared with that in non-AF control group (P<0.05), meanwhile it had no significant difference from that in AF control group. In AF group, the peak effective concentration of H2O2 was 0.5 mumol/L, and the turning concentration was 1 mumol/L. The H2O2 concentration-current density curve in AF group was similar to that in non-AF group, but the turning point shifted to the right, indicating that the way that H2O2 acted on ion channels in AF was the same as that in non-AF, however, the sensitivity of ion channels to H2O2 was decreased in AF. Vitamin C reversed these changes induced by H2O2, and did not affect the characteristics of ion channels. H2O2-induced electrophysiological changes in human atrial myocytes were similar to atrial electrical remodeling (AER) in AF, suggesting that ROS might induce AF. Meanwhile, H2O2 also could aggravate AER in AF, contributing to the maintenance of AF. The results suggest that antioxidants might play a significant role in the prevention and treatment of AF.

Hepatocyte growth factor combined with insulin like growth factor-1 improves expression of GATA-4 in mesenchymal stem cells cocultured with cardiomyocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In a suitable microenvironment, bone marrow mesenchymal stem cells (BMSCs) can transdifferentiate into myocardial cells whose special gene can be expressed as structural proteins. Growth factor (GF) plays an important role in the cell migration, survival and differentiation. However, the effect of GF on the cellular differentiation is not well understood. In this study, the hepatocyte growth factor (HGF) and insulin like growth factor-1 (IGF-1) were used in the mixed culture of BMSCs and myocardial cells and the effects of these growth factors on the GATA-4 expression of BMSCs were investigated.</p><p><b>METHODS</b>BMSCs were isolated from the marrow of rabbit femurs and tibias and foetal rabbit ventricular myocytes were isolated with trypsin sequential digestion. These two kinds of cells were cocultured in a ratio of 1:1 for 6 weeks; cocultured cells with added HGF and IGF-1 were the experimental group. The differentiated BMSCs were collected using the laser capture, microdissection system and their RNA isolated. Immunocytochemical staining, transmission electron microscopy and reverse transcription-polymerase chain reaction were used to evaluate the transformation of the stem cells into cardiomyocytes like cells.</p><p><b>RESULTS</b>When cultured separately, BMSCs did not express alpha-actin and the stem cells had many nucleoli. However, when cocultured with cardiomyocytes, BMSCs expressed alpha-actin and the cardiac transcription factor GATA-4 and showed cardiomyocyte like ultrastructure. In comparison with the control group, the experimental group exhibited the enhanced expression level of GATA-4. The GATA-4 expression of BMSCs increased gradually following the addition of HGF and IGF-1, reached the maximal level after two weeks and decreased slightly thereafter.</p><p><b>CONCLUSIONS</b>BMSCs can transdifferentiate into cardiomyocytes like cells and express the cardiac transcription factor GATA-4 after being cocultured with myocardial cells. HGF and IGF-1 can stimulate transdifferentiation of BMSCs into cardiac phenotype and enhance the expression of GATA-4. These results indicate that growth factors have a great potential in clinical cellular therapy.</p>

Bentall operation combined with total arch replacement and stented elephant trunk implantation for serious Debakey I aortic dissecting aneurysm / 中华外科杂志

<p><b>OBJECTIVE</b>To summarize the clinical experience of Bentall operation combined with total arch replacement and stented elephant trunk implantation for serious Debakey I aortic dissecting aneurysm.</p><p><b>METHODS</b>Twelve patients with serious Debakey I aortic dissecting aneurysm underwent surgical treatment from January 2005 to December 2007. There were 10 male and 2 female with the mean age of (40.1 +/- 9.5) years old. There were acute aortic dissection in 9 cases, chronic aortic dissection in 3 cases. The inner diameter of aorta was (5.3 +/- 1.8) cm. There were Marfan syndrome in 4 cases, aortic regurgitation in all cases, severely persistent chest pain in 9 cases, acute left heart failure in 8 cases, and cardiac tamponade in 4 cases. Bentall operations combined with total arch replacement and stented elephant trunk implantation were performed by using deep hypothermic circulatory arrest and antegrade selective cerebral perfusion in all cases.</p><p><b>RESULTS</b>Urgent surgery underwent in 9 cases. The mean interval between the onset of aortic dissection and the accomplishment of surgery was (41.0 +/- 15.9) hours. Cardiopulmonary bypass time was (191 +/- 26) min, average cross clamp time was (134 +/- 31) min, and average deep hypothermic circulatory arrest time was (50.0 +/- 14.5) min. One patient died in hospital. The time stayed in ICU was 3 to 27 d. Mental disorder in 6 cases, hemi-paralysis in 1 case, amputation in 1 case, hemorrhage of anastomosis in 1 case, hemorrhage of alimentary tract in 1 case, and pleural effusion in 4 cases were recorded. Eleven cases were followed-up for 8 weeks to 36 months. There were no bending of the stents and no obstruction in the vascular prosthesis.No re-operation was needed. One case died 6 months postoperatively.</p><p><b>CONCLUSION</b>Bentall operation combined with total arch replacement and stented elephant trunk implantation is safe and effective for serious Debakey I aortic dissecting aneurysm, while good organs protection and consummate cardiopulmonary bypass were taken.</p>

Surgical treatment of posttraumatic foreign bodies in the heart or great vessels / 中华医学杂志(英文版)

Posttraumatic foreign bodies in the heart or great vessels is rare, which may cause cardiac tamponade, bleeding, shock, infection, embolism, arrhythmia, valve dysfunction, etc. The foreign bodies can be removed by surgery or percutaneous intervention. In this report we reviewed our experience in managing posttraumatic foreign bodies in 13 patients at our institution from 1992 to 2002.

Effect of inducible nitric oxide synthase on intestinal microcirculation in endotoxic shock / 生理学报

To investigate the changes of intestinal microcirculation in endotoxic shock and the effect of inducible nitric oxide synthase (iNOS) on intestinal microcirculation, endotoxic shock was induced by intravenous injection of lipopolysaccharide (LPS) in mice. Mean arterial pressure (MAP) was monitored throughout the experimental procedure. The velocity and flux of red blood cell (RBC) in villus tip arteriole and capillaries were measured by FITC-labeled erythrocytes and intravital microscopy. The effect of iNOS was determined by targeted disruption of mice iNOS-gene and administration of S-methylthiourea sulfate (SMT), a selective inhibitor of iNOS, before LPS injection. No significant differences in MAP, RBC velocity and flux at baseline were found among wild type mice, SMT pretreated mice and iNOS-gene knockout mice. LPS induced a dramatic fall of MAP in wild type mice. The decrease of MAP was significantly restored in iNOS-gene knockout mice and in wild type mice received SMT before LPS injection. The velocity and flux of RBC in villus tip arteriole and capillaries decreased markedly after LPS injection in wild type mice, while significantly higher velocity and flux of RBC were found in iNOS-gene knockout mice and SMT-pretreated mice both 60 and 120 min after LPS injection. The results demonstrate that iNOS plays an essential role in the intestinal microcirculation disturbance which occurs in endotoxic shock.

Diagnosis and treatment of traumatic tricuspid valve insufficiency / 中华创伤杂志(英文版)

Traumatic tricuspid valve insufficiency (TTVI) is a relatively uncommon disease. To summarize the experience in the diagnosis and treatment of TTVI, we have analyzed the clinical data of 3 patients with TTVI who were admitted to the department of cardiac surgery of our hospital between April 1997 to April 2002. Relevant literatures have also been reviewed.