Mitochondrial damage in early stage of pressure ulcer in rats / 基础医学与临床

Objective To investigate the mitochondrial damage and its effect in early stage of pressure ulcer in rats.Methods Forty rats were randomly divided into 5 groups(n=8), control group(Con group) rats without stress, the experimental group was treated with of 170 mmHg for 2 h and relax 0.5 h as one cycle(1C), experi-mental group was divided into 3C, 6C, 9C and 12C group.The pathological changes of the compressed muscle tissue of the rats in each group were observed by HE staining , Western blot was used to detect the expression of Bcl-2 and Bax in the compressed tissue , and the ultrastructure of muscle fibers and mitochondria were observed by transmission electron microscope .Results There were pathological damage and gradually increased in the ex-perimental groups, with the increase of compression cycle; the expression of Bcl-2 in each experimental group was significantly increased as compared with the control group(P<0.05), in the 3C group reached the peak, and then decreased; the expression of Bax was increased gradually with the increase of compression cycle ( P<0.05) , and in the 12C group reached the peak;with the increase of the compression cycle the muscle fibers of each experimental group appeared gradually increased pathological damage:disorder, dissolution and fracture, the ridge of the mitochondria disappeared, vacuolar degeneration, et al.Conclusions In the early stage of pres-sure ulcer in a rat , it brings occurred mitochondrial damage and induces apoptosis .

Effect of spironolactone on cardiac remodeling after acute myocardial infarction / 世界急诊医学杂志（英文）

BACKGROUND: Few studies have reported the effect of aldosterone receptor antagonist (ARA) on myocardial remodeling after acute myocardial infarction (AMI). This study was undertaken to investigate the preventive effect of ARA on myocardial remodeling after AMI.METHODS: A total of 616 patients who had been admitted into the CCU of the First Affiliated Hospital of Harbin Medical University from January 2008 to January 2010 were studied prospectively. Only 528 patients were observed completely, including 266 of the control group and 262 of the treatment group. There was no statistical difference in age, gender, medical history, admission situation, and treatment between the two groups (P>0.05). The preventive effects of spironolactone on cardiac remodeling, left ventricular function, renal function and blood levels of potassium were evaluated by echocardiography, serum potassium and serum creatinine at one-month and one-year follow-up.RESULTS: The echocardiography indicators such as LVESD, LVEDD, LVEF, LAD-ML and LAD-SI were signifi cantly improved in the treatment group compared with the control group at one year (P<0.05). In the treatment group, LVESD, LVEDD, LVPWT, LVEF, LAD-ML and LAD-SI were more significantly improved at one year than one month (P<0.05,P=0.007 to LVEF), and in the control group LVEF was more signifi cantly improved at one year than one month (P=0.0277). There were no signifi cant differences in serum potassium and serum creatinine levels between the two groups.CONCLUSION: On the basis of conventional treatment, the early combination of low-dose spironolactone (20 mg/d) could inhibit cardiac remodeling at late stage and prevent heart failure.

Impact of emergency percutaneous coronary intervention on outcomes of ST-segment elevation myocardial infarction patients complicated by out-of-hospital cardiac arrest / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cardiac arrest is one of the most serious complications of acute myocardial infarction (AMI), especially in the out-of-hospital patients. There is no general consensus as to whether percutaneous coronary intervention (PCI) is effective in treating ST-segment elevation myocardial infarction (STEMI) patients complicated by out-of-hospital cardiac arrest (OHCA). In our study, we evaluated the efficacy of PCI in treating STEMI patients complicated by OHCA through observing their clinical conditions in hospital; including total mortality, adverse cardiac events, stroke, acute renal failure, and gastrointestinal bleeding events.</p><p><b>METHODS</b>A total of 1827 STEMI patients were enrolled in this study, where 81 were STEMI with OHCA. Between the patients with and without OHCA, and the OHCA patients with and without PCI, we compared the clinical characteristics during hospitalization, including total mortality and incidences of adverse cardiac events, and stroke.</p><p><b>RESULTS</b>Compared to the patients without OHCA, the OHCA patients had significantly lower systolic blood pressure (P < 0.05) and a faster heart rate (P < 0.05), and a higher percentage of Killip class IV or Glasgow coma scale (GCS) ≤ 7 on admission (P < 0.001). And the in-hospital mortality was higher in the OHCA patients (55.6% vs. 2.4%, P < 0.001). Comparing the OHCA patients without PCI to the patients with PCI, there was no obvious difference of heart rate, blood pressure or the percentage of Killip class IV and GCS ≤ 7 on admission, but the incidences of cardiogenic shock, stroke were significantly lower in the with-PCI group during hospitalization (P < 0.001, P < 0.05). And the in-hospital mortality of the OHCA patients receiving PCI was significantly lower (36.7% vs. 84.3%, P < 0.001).</p><p><b>CONCLUSIONS</b>During hospitalization, the incidence of adverse events and mortality are higher in the STEMI with OHCA patients, comparing with the STEMI without OHCA. Emergency PCI reduces the incidence of adverse events and decreases mortality during hospitalization, which is effective for treating STEMI with OHCA patients.</p>

A prospective randomized trial of poly-DL-lactic acid absorbable and metallic screws for treatment of syndesmotic disruptions / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the clinical effect of poly-DL-lactic acid (PDLLA) absorbable screws and titanium metallic screws in the treatment of syndesmotic disruptions in ankle fractures.</p><p><b>METHODS</b>In this prospective, randomized clinical trial, 58 patients with or suspected of syndesmotic disruption associated with ankle fractures were randomly allocated to receive either bioabsorbable PDLLA or metallic titanium screwing fixation. Using preoperative radiography and intraoperative hook test, syndesmotic disruption was confirmed in 47 cases (25 with metallic screwing and 22 with PLLA screwing). Statistical analyses were performed at 6 months postoperatively to compare the AOFAS score, range of motion of the joint, TFCS width and TFO width on anteroposterior view radiographs, and inflammatory reactions between the two groups.</p><p><b>RESULTS</b>The PDLLA screws showed good therapeutic effect similar to that of titanium metallic screws in syndesmosis fixation in these patients. No significant differences were found in the AOFAS score, range of motion of the joint, or TFCS width or TFO width between two groups (P>0.05). One patient in PDLLA screw group showed inflammatory reactions to the implants.</p><p><b>CONCLUSION</b>PDLLA screws allow effective and reliable stabilization of syndesmotic disruptions without a second operation for screw removal.</p>

Outcome of patients with ST-elevation myocardial infarction complicated by pre-hospital cardiac arrest underwent emergency percutaneous coronary intervention / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the outcome of ST-elevation acute myocardial infarction (STEMI) patients complicated pre-hospital cardiac arrest underwent percutaneous coronary intervention (PCI).</p><p><b>METHODS</b>From September 2004 to November 2008, 1446 consecutive patients with acute STEMI underwent PCI in our department. 49 out of 1446 patients complicated by pre-hospital cardiac arrest. Clinical outcome including total mortality, adverse cardiac events, stroke and bleeding events during the hospitalization period and within 1 year after discharge was compared between patients with or without pre-hospital cardiac arrest.</p><p><b>RESULTS</b>PCI success rate was similar (85.7% vs. 88.8%, P = 0.497) while the incidence of in-hospital cardiogenic shock 22.4% vs. 3.0%, P < 0.001 and cardiac arrest (44.9% vs. 5.9%, P < 0.001) and in-hospital mortality (36.7% vs. 2.0%, P < 0.001) were significantly higher in patients with pre-hospital cardiac arrest than patients without pre-hospital cardiac arrest. Time from symptom onset to emergency treatment, asystole as initial rhythm, Glasgow coma scale (GCS ≤ 7) and cardiogenic shock on admission were independent risk factors of in-hospital death in patients with pre-hospital cardiac arrest. During follow up, incidences of overall mortality, re-infarction, revascularization and stroke were similar between the two groups.</p><p><b>CONCLUSIONS</b>STEMI patients with pre-hospital cardiac arrest undergoing emergency PCI are facing higher risk of cardiogenic shock and cardiac arrest and higher in-hospital mortality compared to those without pre-hospital cardiac arrest. However, the post-hospital discharge outcome was similar between the two groups.</p>

Intracoronary nitroprusside in the prevention of the no-reflow phenomenon in acute myocardial infarction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>No-reflow phenomenon during percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) is a predictive factor of continuous myocardial ischemia, ventricular remodeling and cardiac dysfunction, which is closely associated with a worse prognosis. This study aimed to evaluate intracoronary nitroprusside in the prevention of the no-reflow phenomenon in AMI.</p><p><b>METHODS</b>Ninety-two consecutive patients with AMI, who underwent primary PCI within 12 hours of onset, were randomly assigned to 2 groups: intracoronary administration of nitroprusside (group A, n = 46), intracoronary administration of nitroglycerin (group B, n = 46). The angiographic results were observed. The real-time myocardial contrast echocardiography (RT-MCE), including contrast score index (CSI), wall motion score index (WMSI), transmural contrast defect length (CDL) and serious WM abnormal length (WML) were recorded at 24 hours and 1 week post-PCI. High sensitivity C-reactive protein (Hs-CRP) was examined by immune rate nephelometry. N-terminal prohormone brain natriuretic peptide (NT-proBNP) was tested with enzyme-linked immunosorbent assay. Patients were followed up for six months. Major adverse cardiac events (MACE) were recorded.</p><p><b>RESULTS</b>The incidence of final TIMI-3 flow in group A was much higher than that in Group B (P < 0.05), final corrected TIMI frame count (cTFC) in group A decreased significantly than that in group B (P < 0.01). The CSI, CDL/LV length, WMSI and WL/LV length in group A were significantly lower than that in group B (P < 0.01). Levels of Hs-CRP and NT-proBNP at 1 week post-PCI decreased significantly in group A than that in group B (P < 0.01). Patients were followed up for 6 months and the incidence of MACE in group A was significantly lower than that in group B (P < 0.05).</p><p><b>CONCLUSION</b>Intracoronary nitroprusside can improve myocardial microcirculation, leading to the decrease of the incidence of no-reflow phenomenon and better prognosis.</p>

Intensive atorvastatin therapy in patients with acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To assess the safety and efficacy of 40 mg daily atorvastatin in patients with acute myocardial infarction.</p><p><b>METHODS</b>A total of 1102 patients with AMI admitted to our hospital from 2003 to 2007 were assigned to atorvastatin 40 mg daily within 24 hours of hospitalization and continued till 3 months post discharge. Patients with LDL-C < 2.0 mmol/L or increased liver enzyme level (3 times higher than normal) at discharge received atorvastatin 20 mg daily. Lipid profiles, high-sensitivity C-reactive protein, liver enzyme level were measured at admission, hospital discharge and 3 months after discharge.</p><p><b>RESULTS</b>(1)The mean hospitalization duration was (10.17 +/- 1.83) days. LDL-C was continuously decreased [(3.24 +/- 1.04) mmol/L at admission, (2.27 +/- 2.00) mmol/L at discharge and (1.48 +/- 0.78) mmol/L at 3 months after discharge, all P < 0.05]. HDL-C decreased from (1.45 +/- 0.38) mmol/L to (1.20 +/- 0.30) mmol/L at hospital discharge, then increased to (1.65 +/- 1.79) mmol/L at 3 months after hospital discharge (all P < 0.05). TC and apoB were also significantly decreased from admission to discharge (all P < 0.05). (2) high-sensitivity C-reactive protein level significantly decreased from admission to hospital discharge and at 1 months after hospital discharge [(49.71 +/- 50.46) mg/L vs. (8.80 +/- 17.66) mg/L vs. (2.61 +/- 2.30) mg/L, all P < 0.05]. (3) Increased ALT > 120 U/L (3 times higher than normal) were found in 127(11.25%), AST > 120 U/L were found in 26(2.40%) patients at discharge. There were still 4 patients with increased ALT (> 120 U/L) at 1 months after discharge and all returned to normal at 3 months after discharge.</p><p><b>CONCLUSION</b>Intensive atorvastatin therapy with a dose of 40 mg daily is safe and effective for patients with AMI.</p>

The efficacy of percutaneous coronary intervention combined percutaneous thrombectomy on coronary thrombotic lesions in patients with acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of percutaneous coronary intervention (PCI) combined percutaneous thrombectomy on coronary thrombotic lesions in patients with acute myocardial infarction (AMI).</p><p><b>METHODS</b>PCI were performed in 56 patients with AMI and positive coronary thrombus shown by angiography and these patients were randomly divided into PCI therapy group (n = 28) and PCI combined percutaneous thrombectomy group (n = 28). Real-time myocardial contrast echocardiography (RT-MCE) was performed at 24h and 1 week after PCI. Contrast score index (CSI), regional wall motion score index (WMSI), endocardial length of contrast defect (CDL), and wall motion abnormality (WML) were calculated. The plasma level of hs-CRP was measured by immunonephelometry. The plasma concentration of N-terminal proB-type natriuretic peptide (NT-proBNP) and matrix metalloproteinase-9 (MMP-9) were detected by enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>CSI, WMSI, CDL and WML at 24 hours and 1 week post procedure as well as the levels of hs-CPR and NT-proBNP at 1 week post procedure [(4.56 +/- 1.98) mg/L vs. (5.96 +/- 2.03) mg/L, P < 0.05; (544.7 +/- 185.3) pmol/L vs. (897.6 +/- 215.9) pmol/L, P < 0.01] were significantly lower in PCI combined percutaneous thrombectomy group than those in PCI group in various time points. There were no differences in the plasma level of MMP-9 between the two groups [(672.7 +/- 175.9) microg/L vs. (609.6 +/- 196.5) microg/L, P > 0.05] at 1 week after PCI.</p><p><b>CONCLUSIONS</b>PCI combined percutaneous thrombectomy can significantly reduce no-reflow phenomenon, improve microcirculation and myocardial dysfunction. Thus PCI combined percutaneous thrombectomy is a feasible therapy in patients with AMI.</p>

Clinical studies on fifty-seven Chinese patients with combined methylmalonic aciduria and homocysteinemia / 中华儿科杂志

<p><b>OBJECTIVE</b>Methylmalonic aciduria (MMA) is a common one of the congenital disorders of organic acids metabolism. Some of the patients with the disorder are complicated with homocysteinemia. Recently, gas chromatography-mass spectrometry (GCMS) has been used to diagnose MMA in China. However, the diagnosis of the patients with combined MMA and homocysteinemia is often delayed. In this study, the natural history, clinical features and outcome of 57 Chinese patients with combined MMA and homocysteinemia were investigated.</p><p><b>METHODS</b>From 1996 to 2006, 96 MMA patients from 16 provinces or cities were diagnosed in our hospital by urine organic acids analysis using GCMS. Homocysteinemia was found by serum and urine total homocysteine determination using a fluorescence polarization immunoassay.</p><p><b>RESULTS</b>Fifty-seven of the 96 MMA patients (59.4%, 32 males and 25 females) were found to have combined MMA and homocysteinemia. They had markedly increased urine methylmalonic acid, total serum homocysteine (81.5 to 226.5 micromol/L vs. normal range 4.5 to 12.4 micromol/L) and urine homocysteine (79.1 to 414.5 micromol/L vs. normal range 1.0 to 25.0 micromol/L). Thirteen (22.8%) of them presented with symptoms resembled hypoxic-ischemic encephalopathy in the neonatal period. Fourteen (24.6%) patients had the onset at the age of one month to 1 year with mental retardation, vomiting and epilepsy. Nine (15.8%) showed developmental delay, seizures, poor appetite or anemia from the age of 1 to 3 years. Eighteen (31.6%) had psycho-motor degeneration at the age of 6 to 15 years. Among them, 7 patients experienced multiple organ dysfunctions with liver dysfunction, hematuria, renal failure and peripheral neuropathy. Three (5.3%) patients developed progressive mental degeneration, motor disorders and anorexia at the ages of 16, 24 and 34 years. Eleven (19.3%) patients ultimately died; 5 (8.8%) of them were diagnosed postmortem. Forty-six (80.7%) patients were treated with vitamin B12, folic acid, L-carnitine and betaine supplementation and 11 (19.3%) of them recovered completely.</p><p><b>CONCLUSIONS</b>Combined MMA with homocysteinemia is a common form of MMA in China. The clinical spectrum of the patients varies from severe neonatal-onset forms with high mortality to milder forms with adult-onset. Serum or urine total homocysteine analysis is important for the deferential diagnosis of the patients with MMA.</p>

The prognostic value of hyponatremia in patients with acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the prognostic significance of hyponatremia in patients with AMI.</p><p><b>METHODS</b>The study population consisted of 670 patients with AMI in coronary care unit in our hospital from January 2003 to December 2004. The patients were designed into three groups according to serum sodium concentration within twenty four to forty eight hours following the onset of AMI: Group A. Na(+) > or = 135 mmol/L; Group B. Na(+) 120-135 mmol/L; Group C. Na(+) < or = 120 mmol/L. The data of myocardial enzymes, myocardial infarction size, heart function and inhospital mortality were analyzed retrospectively.</p><p><b>RESULTS</b>1. The inhospital mortality of each group: group A was 7.6% (17/225), group B was 8.1% (34/421), group C was 33.3% (8/24). The difference between group C and group B or group A was significant. The P value was little than 0.05. 2. Activities of serum creatine phosphatase kinase and serum creatine phosphatase kinase isoenzymes and myocardial infarction sizes in each group were different (P < 0.05). 3. 59 cases of all died and 611 cases of all recovered in duration of hospital stay. Serum sodium concentrations of the recovered group were (133.00 +/- 5.25) mmol/L, and that of the died group were (122.00 +/- 7.25) mmol/L (P < 0.01). 4. In a multivariate logistic regression analysis, hyponatremia was associated with 30-day mortality in patients with AMI. In analysis of the association between the degree of hyponatremia and outcome, we observed that the risk of 30-day mortality increased with the severity of hyponatremia.</p><p><b>CONCLUSION</b>Hyponatremia may be one of the important markers that predict a worse prognosis in patients with AMI.</p>

Effects of angiotensin converting enzyme inhibitor, angiotensin II type I receptor blocker and their combination on postinfarcted ventricular remodeling in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Transforming growth factor (TGF) beta(1)-Smads signal plays an important role in cardiac remodeling following myocardial infarction (MI). In addition, both angiotensin converting enzyme inhibitor (ACEI) and angiotensin II type I receptor blocker (ARB) can effectively prevent left ventricular remodeling. The current study focused on whether the combination of ACEI and ARB is more beneficial for preventing ventricular remodeling and whether Smad proteins mediate this beneficial effect.</p><p><b>METHODS</b>MI was induced by ligating the left anterior descending coronary artery in rats. Twenty-four hours after ligation, the survived rats were randomly divided into five groups and treated for 8 weeks: placebo group, ACEI group (benazepril 10 mg.kg(-1).d(-1)), ARB group (irbesartan 50 mg.kg(-1).d(-1)), ACEI + ARB group (benazepril 10 mg.kg(-1).d(-1) + irbesartan 50 mg.kg(-1).d(-1)) and control group (sham-operated rats). After 8 weeks, we examined the following indexes: the ratio of ventricular weight to body weight (VW/BW), left ventricular end diastolic dimension (LVDd), ejection fraction (EF), fractional shortening (FS), ratio of E-wave to A-wave velocity, collagen of noninfarcted zone, the mRNA expression of TGFbeta(1), Smad 2, and Smad 3 by RT-PCR in noninfarcted zone, the protein expression of Smad 2 and Smad 3 in noninfarcted zone by Western blot.</p><p><b>RESULTS</b>VW/BW significantly increased in the placebo groups compared with that in the control group (P < 0.01). This increase was limited in ACEI, ARB, and combined groups (P < 0.01 compared with placebo group). There was no significant difference among the three actively treated groups. Collagen was increased in placebo group (5.68 +/- 0.5)% compared with that in control group (P < 0.01). ACEI, ARB and combined treatment attenuated this increase of collagen [(4.3 +/- 0.5)%, (3.5 +/- 0.5)%, (3.2 +/- 0.4)%] in comparison with that in placebo group (P < 0.01 respectively). Combined treatment showed more significant effect on collagen deposition. EF and FS significantly decreased, LVDd and E/A significantly increased in placebo group compared with that in control group (P < 0.01 respectively). ACEI, ARB and combined treatment ameliorated these indexes (P < 0.01 compared with placebo group). The mRNA expression of TGFbeta(1), Smad 2, and Smad 3 (0.700 +/- 0.045, 0.959 +/- 0.037 and 0.850 +/- 0.051) increased in placebo group compared with that in control group (P < 0.01). ACEI, ARB and combined treatment normalized the increase (P < 0.01). Furthermore, ARB and combined treatment proved to be more effective in decreasing TGF beta(1) and Smad mRNA expression than ACEI treatment (P < 0.01). The expression of Smad 2 and Smad 3 protein increased in placebo group compared with that in control group (P < 0.01). ACEI, ARB and combined treatment normalized the increase (P < 0.01). Furthermore, ARB and combined treatment proved to be more effective than ACEI alone (P < 0.01).</p><p><b>CONCLUSIONS</b>TGFbeta(1)-Smads signal activation is correlated with ventricular remodeling following MI. ACEI and ARB treatment prevents ventricular remodeling by inhibiting expression of Smad 2 and Smad 3. ARB and combined treatment are more effective than ACEI alone.</p>

Relationship between plasma brain natriuretic peptide concentration and clinical prognosis in patients of acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the value of brain natriuretic peptide (BNP) in estimating risk stratification in patients with acute myocardial infarction (AMI) and to determine the relationship between BNP and adverse cardiac events after AMI.</p><p><b>METHODS</b>The 135 subjects were selected into the study, including 25 healthy subjects and 110 patients with a first AMI. The plasma concentrations of BNP were measured at two to four days after infarction in patients and healthy controls. Left ventricular function was evaluated by echocardiography with the parameters of left ventricular ejection function (LVEF) after 3 months. Patients were followed up at 12 months. The main outcome measures were heart failure, left remodeling, mortality and other adverse cardiac events at one year.</p><p><b>RESULTS</b>Plasma BNP concentrations in patients with AMI were much higher than those in the health control people (416.7 +/- 208.0 ng/L versus 61.8 +/- 34.1 ng/L, P < 0.01). The BNP count ranged from 5 to 2500 ng/L in AMI patients. There was no association between the BNP count and mortality rate. The development of new congestive heart failure (CHF) was associated with a higher BNP count (P = 0.02). The development of any of the clinical end points (death/CHF/shock) occurred more frequently in patients with a higher BNP count (13.8% for BNP count of < 100 ng/L, 39.1% for BNP count of 100 - 200 ng/L, 43.3% for BNP count of 200 - 400 ng/L, 46.4% for BNP count of > 400 ng/L; P = 0.019). Plasma BNP concentrations remained independently associated with the development of clinical end points in multivariable model that adjusted for potential confounding variables.</p><p><b>CONCLUSION</b>The results of the present study confirm that the elevated BNP count related to the risk stratification and prognosis in patients with AMI. Elevations in BNP count are associated with a higher incidence of new CHF and adverse clinical outcomes after AMI. It could serve as a strong predictor for the subsequent development of poor outcomes in AMI patients.</p>

The effect of homocysteine on fibrinolytic system in human umbilical vein endothelial cells / 中华心血管病杂志

<p><b>OBJECTIVES</b>To investigate the relationship between homocysteine (Hcy) and the fibrinolytic system in acute myocardial infarction (AMI) and human umbilical vein endothelial cells (HUVEC).</p><p><b>METHODS</b>Cultured HUVEC was divided into 10 groups (0, 10, 50, 200, 500 micromol/L Hcy with or without 15 micromol/L of folic acid). There were 53 patients of acute myocardial infarction (AMI) and 48 healthy controls. The plasminogen activator inhibitor-1 (PAI-1) and activator of plasminogen (tPA) antigen levels in HUVEC's supernatant and plasma were measured with Elisa kit. Concentration of plasma Hcy was measured by reverse-phase high-performance liquid chromatography with precolumn derivatization and fluorometric detection in the patients and healthy controls. Total RNA was extracted using the guanidinium isothiocyanate method. The semi-quantification of PAI-1 and tPA mRNA in HUVEC was carried out by reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>(1) PAI-1 mRNA and secreted protein levels were both significantly enhanced by Hcy at the concentration of 500 micromol/L, compared with the control group (P < 0.05). (2) The tPA mRNA and antigen levels were decreased significantly at concentration of 500 micromol/L of Hcy, compared with that of 10 micromol/L Hcy (P < 0.05), but compared with the control group (0 micromol/L), the tPA mRNA and antigen levels of 10 micromol/L of Hcy were much higher (P < 0.05). (3) The addition of folic acid reduced PAI-1 but increased tPA at both mRNA and protein levels, which were both obvious at concentrations of 500 micromol/L Hcy, compared with only Hcy group (P < 0.05). (4) Hcy, tPA, and PAI-1 antigen levels were increased in AMI group. Hcy is a independent risk factor of AMI (P < 0.05). There weren't significant correlation between Hcy and tPA or Hcy and PAI-1 in both groups (P > 0.05), although the coefficient correlation was higher in patients than in controls.</p><p><b>CONCLUSIONS</b>These results suggested that hyperhomo-cysteinemia increased the incidence of thrombotic disease, which may be caused by decreasing the activity of fibrinolytic system, whereas, folic acid may be protective against the toxic action of Hcy.</p>

Relationship between expression of Smad and ventricular remodeling after myocardial infarction in rats / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between expression of Smad3, Smad7 and ventricular remodeling in rats after myocardial infarction.</p><p><b>METHODS</b>Myocardial infarction was induced by left anterior descending coronary artery ligation in rats (n = 11) and sham-operated rats were used as control (n = 10). The rats were sacrificed 8 weeks later. Heart weight/body weight (HW/BW), mean blood pressure, left ventricular end diastolic pressure (LVEDP), collagen content in the un-infarcted area were examined. The mRNA levels of transforming growth factor (TGF)beta(1), Smad 3, Smad7 were determined by RT-PCR.</p><p><b>RESULT</b>Compared with controls, the level of HW/BW, LVEDP and collagen content were significant increased. The mRNA expression of TGFbeta(1) and Smad3 was significantly increased in areas of myocardial infarction, border of the infarction, interventricular septum and right ventricle. The expression of Smad7 mRNA in these areas was decreased.</p><p><b>CONCLUSION</b>These results indicated that TGFbeta(1)-Smads signaling was correlated to the ventricular remodeling after myocardial infarction. Smad3 might promote the process while Smad7 inhibit the process.</p>

Homocysteine' s effect on tPA and PAI-1 gene expression in HUVEC / 中国应用生理学杂志

<p><b>AIM</b>In order to elucidate the relationship between homocysteine (Hcy) and the fibrinolytic system, we examined the effect of Hcy on tissue- type plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) gene expression in human umbilical vein endothelial cells (HUVEC) in vitro.</p><p><b>METHODS</b>Total RNA was extracted from HUVEC exposed to physical and pathological concentrations of Hcy (0, 10, 50, 200, 500 micromol/L ) for 24 hours, using the guanidinium isothiocyanate method. The semi-quantification of tPA and PAI-1 mRNA in HUVEC was carried out by reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>PAI-1 mRNA levels was enhanced by Hcy at concentrations of 500 micromol/L of Hcy, compared with that of 0 micromol/L Hcy (P < 0.05). The mRNA expression of tPA, however, was significantly decreased at concentrations of 500 micromol/L Hcy, compared with that of 10 micromol/L Hcy (P < 0.05), but compared with the control group, the tPA level of 10 micromol/L Hcy was much higher (P < 0.05).</p><p><b>CONCLUSION</b>Hyperhomocysteinemia increases the incidence of cardio cerebral vascular disease, which may be caused by decreasing the activity of fibrinolytic system, whereas, the physiological concentration of Hcy may be decreased the incidence by enhancing the activity of fibrinolytic system.</p>