Time course of ubiquitin and rat component 3 of proteasome expressions and association with common carotid artery intimal proliferation after balloon injury in rats / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the dynamic ubiquitin and rat component 3 of proteasome (RC3) change and association with intimal proliferation in the common carotid artery of rats after balloon injury.</p><p><b>METHODS</b>Male SD rats were randomly divided into two groups: sham operation group (n = 8), ballon injury group at various time points (1, 4, 7, 14, 21, 28-days post injury, n = 8 each). The balloon injury model was established by deendothelializing the rat common carotid aortic artery by inflated 2F balloon catheter. HE staining was used to observe the ratio of intima-media (I/M) thickness of the injured arteries under optical microscopy. The expression levels of ubiquitin and RC3 mRNA were detected with RT-PCR. The expression level of ubiquitin protein was measured by immunohistochemistry method.</p><p><b>RESULTS</b>The maximal intimal proliferation and peak intima-media ratio (2.31 +/- 0.43 vs. control 0.02 +/- 0.005, P < 0.01) were seen at 28th day post injury. The peak expression of ubiquitin was observed at the 7th day post injury (1.33 +/- 0.26 vs. control 0.21 +/- 0.04, P < 0.01) and peak RC3 expression was found at the 14th day post injury (1.35 +/- 0.26 vs. control 0.31 +/- 0.06, P < 0.01). The protein expression of ubiquitin was also seen at the 14th day post injury (21.53 +/- 4.09 vs. control 4.21 +/- 0.78, P < 0.01). The expression of ubiquitin protein was positively correlated with intimal proliferation(r = 0.827, P < 0.05).</p><p><b>CONCLUSION</b>The upregulated ubiquitin and RC3 expressions after balloon injury might play an important role in intimal proliferation in this model.</p>

Diagnostic value of ischemia-modified albumin in patients with acute coronary syndrome / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the diagnostic value of ischemia-modified albumin (IMA) for patients with acute coronary syndrome (ACS).</p><p><b>METHODS</b>We detected the IMA levels by albumin cobalt-binding (ACB) test and observed its dynamic changes in 492 patients with ACS, 74 patients with high blood pressure, 78 patients with viral myocarditis (VMC), 395 patients with acute chest pain (133 patients with acute ACS and 262 follow-up patients due to chest pain), 68 patients underwent percutaneous coronary intervention (PCI) and 830 healthy controls. Cardiac troponin I (cTnI) levels were assayed and electrocardiogram (ECG) recorded in patients with ACS.</p><p><b>RESULTS</b>The optimal diagnostic cutoff point for IMA in this study population was found to be 0.45 ABSU by ROC analysis. The IMA level (ABSU) in ACS group (0.55 +/- 0.11) was significantly higher than that in VMC group (0.38 +/- 0.11) and IMA levels in ACS and VMC groups were both higher than that in control and high blood pressure groups (0.34 +/- 0.08 and 0.35 +/- 0.08, all P < 0.05). IMA levels and the positive rates in patients with ACS were significantly higher (0.54 +/- 0.12 vs 0.44 +/- 0.12, 77.4% vs 39.3%, all P < 0.01) than those in chest pain follow-up group. In 133 patients with ACS, positive rate for IMA was significantly higher than that for cTnI within 1 h of admission (82.0% vs 40.6%, P < 0.01), and was similar at 6 - 24 h after admission (96.2% vs. 95.5%, P > 0.05). In 72 patients presenting to the emergency center within 3 h of acute chest pain and with negative cTnI, positive rate for IMA was 86.1% and for ECG 72.2%, the sensitivity for ACS diagnosis rised to 93.1% with both methods. The IMA leve was higher immediately after PCI than that before PCI (P < 0.05). IMA levels peaked 1d after hospitalization, then decreased gradually and returned to normal 14 days later.</p><p><b>CONCLUSIONS</b>IMA was a useful biochemical marker for the early diagnosis of ACS.</p>

Effect of Simvastatin on the Expression of Ubiquitin and Rat Component 3 of Proteasome in the Common Carotid Artery of Rats After Balloon Injury / 中华高血压杂志

Background The ubiquitin-proteasome pathway(UPP)involves 80%-90% degradation of all in- tracellular proteins.Both ubiquitin and rat component 3 of proteasome(RC3)are hence considered to be central me- diators for cell biology.Objective To evaluate the effect of simvastatin on neointimal hyperplasia and the expres- sion of ubiquitin and rat component 3 of proteasome(RC3)after balloon injury in carotid artery.Methods Thirty- two male SD rats were randomly to receive,low dose(0.4 mg/ng,n=8),or moderate(4 mg/ng,n=8),or high- dose(40 mg/ng,n=8)of simvastatin treatment for 28 days.Common carotid aortic artery was injuried rat ballon. The ratio of intima-media(I/M)thickness was determined.The expression level of ubiquitin and RC3 mRNA were assessed by RT-PCR.The expression level of ubiquitin protein was examined with immunohistochemistry. Results Simvastatin inhibited the expression of ubiquitin and RC3 mRNA and ubiquitin protein in dose dependent manner.The intima-media ratio(-50.2 %)and the expression of ubiquitin(-60.3 %)and RC3 mRNA and ubiq- uitin protein(-60.5 %)was reduced by the high dose simvastatin [40 mg/(kg?d)](P