Inhibition of CaMKII alleviates myocardial ischemia?reperfusion injury by reducing mitochondrial oxidative stress in isolated perfused rat heart / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of calcium/calmodulin-dependent protein kinase II (CaMKII) in myocardial ischemia-reperfusion (IR) injury in isolated perfused rat heart and explore the underlying mechanisms.</p><p><b>METHODS</b>An ischemia-reperfusion (IR) model was prepared using isolated rat hearts perfused with Krebs-Henseleit solution were randomly divided into control group, 2.5 µmol/L KN-93 group, IR (induced by ischemia for 45 min followed by reperfusion for 120 min) group and KN-93+IR group. The myocardial performance was evaluated by assessing the left ventricular pressure. Lactate dehydrogenase (LDH) activity and cTnI content in the coronary flow and the infarct size were determined to evaluate the myocardial injury. The phosphorylation of CaMKII (p-CaMKII) and PLN (p-PLN) and oxidation of CaMKII (ox--CaMKII) were measured with Western blotting. The activity of mitochondrial superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were determined using ELISA.</p><p><b>RESULTS</b>Compared with the control group, KN-93 treatment at 2.5 µmol/L produced no significant effects on cardiac function or performance in rat hearts without IR injury. Myocardial IR injury significantly decreased myocardial performance and mitochondrial SOD activity in the perfused hearts (P<0.01) and caused significantly increased infarct size, LDH activity, cTnI content, expressions of p-CaMKII, ox-CaMKII and p-PLN, and also increased mitochondrial MDA content (P<0.01). KN-93 treatment at 2.5 µmol/L administered before ischemia and before reperfusion markedly attenuated such changes induced by ischemia and reperfusion (P<0.01).</p><p><b>CONCLUSION</b>CaMKII participates in myocardial IR injury in isolated rat heart, and inhibiting CaMKII can alleviate myocardial injury by relieving mitochondrial oxidation stress.</p>

Effect of 2,3-butanedione monoxime on calcium paradox-induced heart injury in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the Effect of 2,3-butanedione monoxime (BDM) on calcium paradox-induced heart injury and its underlying mechanisms.</p><p><b>METHODS</b>Thirty-two adult male SD rats were randomized into 4 groups, namely the control group, BDM treatment control group, calcium paradox group, and BDM treatment group. Isolated Sprague Dawley male rat hearts underwent Langendorff perfusion and the left ventricular pressure (LVP) and left ventricular end-diastolic pressure (LVEDP) were monitored. Left ventricular developed pressure (LVDP) was calculated to evaluate the myocardial performance. Lactate dehydrogenase (LDH) content in the coronary flow was determined. Triphenyltetrazolium chloride staining was used to measure the infarct size, and myocardial cell apoptosis was tested with TUNEL method. Western blotting was used to determine the expression of cleaved caspase-3 and cytochrome c.</p><p><b>RESULTS</b>Compared with the control group, BDM at 20 mmol/L had no effect on cardiac performance, cell death, apoptotic index or the content of LDH, cleaved caspase-3 and cytochrome c at the end of perfusion under control conditions (P>0.05). Calcium paradox treatment significantly decreased the cardiac function and the level of LVDP and induced a larger infarct size (P<0.01), an increased myocardial apoptosis index (P<0.01), and up-regulated expressions of cleaved caspase-3 and cytochrome c (P<0.01). BDM (20 mmol/L) significantly attenuated these effects induced by calcium paradox, and markedly down-regulated the levels of LVEDP and LDH (P<0.01), lowered myocardial apoptosis index, decreased the content of cleaved caspase-3 and cytochrome c (P<0.01), increased LVDP, and reduced the infarct size (P<0.01).</p><p><b>CONCLUSION</b>BDM suppresses cell apoptosis and contracture and improves heart function and cell survival in rat hearts exposed to calcium paradox, suggesting the value of BDM as an potential drug for myocardial ischemia reperfusion injur.</p>

Expression of molecular markers detected by immunohistochemistry and risk of lymph node metastasis in stage T1 and T2 colorecrectal cancers / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the molecular risk factors of lymph node metastasis in stage T1 and T2 colorectal cancers by tissue microarray and immunohistochemistry techniques.</p><p><b>METHODS</b>Two hundred and three patients with stage T1 and T2 colorectal carcinoma who underwent radical surgery from 1999 to 2010 in our department were included in this study. Their clinicopathological data were retrospectively analyzed. Expression of the following 14 molecular markers were selected and assayed by tissue microarray and immunohistochemistry: VEGFR-3, HER2, CD44v6, CXCR4, TIMP-1, EGFR, IGF-1R, IGF-2, IGFBP-1, ECAD, MMP-9, RKIP, CD133, MSI. Chi-squared test and logistic regression were used to evaluate the variables as potential risk factors for lymph node metastasis.</p><p><b>RESULTS</b>The positive expression rates of biomarkers were as following: VEGFR-3 (44.3%), EGFR (30.5%), HER-2 (28.1%), IGF-1R (63.5%), IGF-2 (44.8%), IGFBP-1 (70.9%), ECAD (45.8%), CD44v6 (51.2%), MMP-9 (44.3%), TIMP-1 (41.4%), RKIP (45.3%), CXCR4 (40.9%), and CD133 (49.8%). The positive rate of MSI expression was 22.2%. Both univariate and multivariate analyses showed that VEGFR-3, HER-2, and TIMP-1 were significant predictors of lymph node metastasis. Univariate analysis showed that CD44v6 and CXCR4 were significant significant predictors of lymph node metastasis.</p><p><b>CONCLUSIONS</b>VEGFR-3, HER2 and TIMP-1 are independent factors for lymph node metastasis in stage T1 and T2 colorectal cancers.</p>

Surgical treatment for 140 patients with gastric stromal tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To analyze the outcome of the patients with gastric gastrointestinal stromal tumor(GIST) after surgical treatment and identify the associated risk factors.</p><p><b>METHODS</b>Clinical data and the tissue slices including immunohistochemistry staining of 140 patients with gastric GIST from January 1990 to December 2008 were retrospectively reviewed. SPSS 16.0 for Windows software package was used for statistical analysis.</p><p><b>RESULTS</b>The overall survival rates of 1-, 3-, 5-year were 96.8%, 86.7% and 79.3%, respectively. The survival rates of 1-, 3-, 5-year were 98.1%, 90.0% and 85.4% in patients who underwent complete tumor resection. But the survival rates of 1-, 3-, 5-year were 38.1%, 0 and 0 in patients with incomplete tumor resection. The differences were statistically significant (P<0.05). Gender, preoperative metastasis, tumor size,pathology type,karyokinesis, recurrence and metastasis were associated with survival rates in patients with complete tumor resection by univariate analysis. However, only tumor size, karyokinesis, recurrence and metastasis were associated with survival rates by Cox regression multivariable analysis(P<0.05).</p><p><b>CONCLUSION</b>Surgery remains the main treatment for gastric GIST. Local complete resection is the principal treatment.</p>

Surgical treatment for gastrointestinal stromal tumor / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the effects of surgical treatment for gastrointestinal stromal tumors (GISTs) and influential factors of survival.</p><p><b>METHODS</b>The clinical data and the tissue slices including immunohistochemical staining of 153 cases of GISTs from January 1990 to March 2006 were rechecked retrospectively. All patients were followed up carefully. More attention was paid to the surgical effects and the influential factors of survival.</p><p><b>RESULTS</b>The overall survival rates at 1-, 2-, 3-, 4- and 5-year were 94.9%, 83.3%, 73.3%, 70.5% and 64.3%, respectively. The median survival time for patients with tumor resected completely was 66.0 months, and the 2- and 5-year survival rate were 89.4% and 70.9% respectively. The median survival time was 23.8 months for the patients with tumor resected partly, and only two of these patients survived over 2 years. Gender, tumor sites, preoperative metastasis, tumor size, pathological type, karyokinesis and recurrence and metastasis were related with survival rates for the patients with tumor resected completely on univariate analysis, but tumor size, pathology type, recurrence and metastasis were related with survival rates on Cox regression multivariate analysis (P < 0.05).</p><p><b>CONCLUSIONS</b>Surgery should still be the main therapy for GISTs. Local complete resection is the principal treatment. The survival cannot be improved by extensive resection and lymph nodes clearance.</p>