In Situ Electrochemical Monitoring of the Crevice Corrosion Process of the 7075-T651 Aluminium Alloy in Acidic NaCl and NaNO3 Solution.

The crevice corrosion of the 7075-T651 aluminium alloy was investigated using in situ electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves (PC), and H+ sensors in acidic NaCl solution with different contents of NaNO3. In the solution without NaNO3, the pH in the crevice increased rapidly and gradually reached a relatively stable status. The corrosion of the aluminium alloy in the crevice was inhibited and crevice corrosion could not be initiated. In the solution with NaNO3, the pH increased rapidly at the initial immersion period and then decreased gradually. The corrosion of the aluminium alloy inside the crevice could be enhanced and the corrosion of the aluminium alloy outside crevice could be inhibited. This triggered crevice corrosion in the solution with NaNO3. The inhibited corrosion outside the crevice can be attributed to the improved passive film of the specimen outside the crevice by nitrate. The accumulated secondary products of ammonia inside the crevice led to selective dissolution of copper, which triggered the nucleation of pitting corrosion and promoted the corrosion of the specimen inside the crevice.

Long-term prognostic value of analysis of sympathetic drive by myocardial 123I-metaiodobenzylganidine scintigraphy in chronic heart failure.

BACKGROUND: The over increase of sympathetic drive in chronic heart failure (CHF) is with main responsibility for the deterioration and mortality of the disease. Myocardial (123)I-metaiodobenzylganidine (MIBG) scintigraphy is a non-invasive convenient method to assess sympathetic dysfunction in patients with CHF. The aim of the study was to detect if sympathetic antidrive analysed through myocardial MIBG scintigraphy plays a crucial role in long-term prognosis in CHF. METHODS: Sixty-four enrolled patients underwent myocardial MIBG scintigraphy, and their plasma concentration of brain natriuretic peptide (BNP), myocardial contractile reserve (MCR), rest left ventricular ejection fraction (rest LVEF) and New York Heart Association (NYHA) function class were assessed. They were separated into groups according to median of above parameters. Endpoint was cardiac death and it was recorded in each group during average 54 months' follow-up. RESULTS: At the end of follow-up, group with lower ratio of heart/mediastinum (H/M) had more death events (P = 0.001), and its BNP level was higher and MCR level was lower (P = 0.003 and 0.001, respectively); but its rest LVEF and NYHA function class were not significantly different. H/M, MCR and BNP correlated closely with death (P = 0.000, 0.000 and 0.001, respectively). Among the three indicators the death risk ratio (RR) of H/M was 4.66, more than MCR and BNP (1.88 and 2.56, respectively). However, rest LVEF and NYHA function class did not correlate with death (P = 0.652 and 0.384, respectively). The group with lower H/M and MCR, higher BNP had much more death than that with higher H/M and MCR, lower BNP, the RR being 12.8. CONCLUSIONS: Myocardial MIBG scintigraphy is a long-term prognostic marker in CHF. BNP, MCR are also excellent predictors of long-term prognosis in CHF, but not stronger than myocardial MIBG scintigraphy. If the three indicators were joined together, the prediction would become most powerful. Rest LVEF and NYHA have no significance in long-term prediction of CHF.

[A 50-year study on the epidemiology of hypertension in Heilongjiang Province of China].

OBJECTIVE: To assess the epidemiological characteristics of hypertension and its attributing factors in Heilongjiang province and establish a comprehensive basis for the prevention and control of hypertension in this region. METHODS: Using the stratified chunk method, a survey lasting 50 years was conducted on a sample of 299 677 (including 158 782 males and 140 895 females) patients, aged 15 and above, residing in both rural and urban areas of Heilongjiang province from 1958 to 2007. Both blood pressure measurement and analysis on attributing factors of hypertension were carried out in 1958, 1979, 1991, 1999 and 2007. RESULTS: The prevalence of hypertension was significantly higher in Heilongjiang than in other provinces. It elevated annually, reaching a 3-fold increase in 50 years with an accelerating pace (17.06% to 25.69%) in the recent 8 years. Among the people examined, the prevalence of hypertension increased with aging. Furthermore, the prevalence of hypertension varied among different professions. Office workers had the highest prevalence (41.67%). Compared with; female population, male participants had a much higher prevalence before the age of 55 (P<0.0001). Body mass index, gender, hypertriglyceridemia, age, low-high density lipoprotein cholesterol and family history were identified as major risk factors for the development of hypertension in Heilongjiang province. However, the awareness (48.90%), treatment (25.33%) and control (4.32%) rates of hypertension in this region were relatively low. CONCLUSION: The results of the present study identified Heilongjiang province as a high-risk region for hypertension. It also suggests the necessity to plan and implement actions for the effective prevention and treatment of hypertension in this region.

[A survey of medical therapies for chronic heart failure in primary hospitals in China].

OBJECTIVE: To investigate the current medicine therapy of CHF in primary hospitals in China, and to propose the improvement ways. METHODS: Physicians from 2066 primary hospitals in 17 areas of China completed investigating questionnaires about their medicine therapy of CHF. 2100 pieces of valid questionnaires were collected totally. Input all the data to computer 2 times and check up repeatedly till to be sure that there were no mistakes in the database, then to make statistics analysis by the SPSS soft kit. RESULTS: The current medicine therapy of CHF in primary hospitals in China was not optimal: the use rate of large dosage digitalis (defined as oral digitalis > or = 0.25 mg/d) was 10 percent; the use rate of beta-blocker and ACEI (angiotensin-II converting enzyme inhibitors) was still low (40% and 80%, respectively); the use rate of the target dose of beta-blocker and ACEI were even lower (1% and 2%, respectively), in some underdeveloped areas they were zero; but in some developed areas the current medical therapy of CHF was better. CONCLUSIONS: It is imperative to improve the current medicine therapy of CHF in primary hospitals in China. The first step might be to let more doctors who work in primary hospitals be familiar with "Guideline of CHF" and could practise it in clinic; the second one might be to open Out-patient Heart Failure Clinics in primary hospitals in order to that patients could be followed up regularly, so that to amend the current state.

[Plasma concentration of NT-proBNP in patients with acute coronary syndrome correlated with the severity of the diseases?].

OBJECTIVE: To elucidate whether the plasma concentration of NT-proBNP in patients with acute coronary syndrome (ACS) correlated with severity of the diseases and whether NT-proBNP is a reliable biochemical marker correctly indicates the severity of ACS. METHODS: Eighty-nine subjects came from CCU of Cardiology Department of People's Hospital Beijing University from October 2003 to June 2004 and aged 34-85 y (66.89 +/- 11.12 y). In this study the spectrum of ACS only included unstable angina pectoris (UA) and acute myocardial infarction (AMI). Patients with UA were separated into 3 groups by Braunwald classes and those with AMI were separated into 4 groups by Killip classes when their venous blood samples were collected. Plasma concentration of NT-proBNP was measured by enzyme linked immunoabsorbent assay. Data was estimated by SPSS. RESULTS: The concentration of NT-proBNP in patients with ACS was dramatically correlative with the severity of the diseases: with the upgrading of Braunwald classes, the concentration of NT-proBNP in patients with UA increased gradually; in patients with AMI it also raised gradually with the upgrading of killip classes; furthermore, the plasma concentration of NT-proBNP in patients with AIM increased much more than that in patients with UA when they are at the similar NYHA functional class. CONCLUSION: Plasma concentration of NT-proBNP in patients with ACS might be a reliable biochemical marker which can objectively indicate the degree of this diseases.

[A pilot survey of the main causes of chronic heart failure in patients treated in primary hospitals in China].

OBJECTIVE: The aim of this investigation is to make clear the main causes of chronic heart failure (CHF) in patients who receive management in primary hospitals in China and to provide scientific evidence for the prevention of CHF in primary hospitals in China. METHODS: The first three main causes of CHF were determined in the way of answering questionnaires by local doctors from 2066 local hospitals (from one hospital at least one doctor) in 17 areas, we got 2100 pieces of valid answer. Input these forms to computer 2 times, check repeatedly till being sure that there were no mistakes in them and then make statistics with SPSS soft kit. RESULTS: In primary hospitals in our country, the first three main causes of CHF are coronary heart disease, hypertension and rheumatic heart disease. In some places chronic pulmonary heart disease is also a main cause of CHF in primary hospitals. CONCLUSIONS: The primary and secondary prevention of coronary heart disease and hypertension is certainly important in the prevention of CHF, but it is equally important to prevent rheumatic heart disease and chronic pulmonary heart disease.

Hypertensive epidemiology in Heilongjiang Province in China.

OBJECTIVE: To assess the epidemiology features of hypertension in Heilongjiang Province, China. METHODS: From 1959 to 1999, 289,157 people in total, ages > or = 15-year old (male 154,091, female 135,066) were investigated four times by a stratified chunk method in rural and urban areas in Heilongjiang Province. After a staff training program, this survey on blood pressure and risk factors was carried out under a worldwide uniform protocol with standardized method and interrelated quality control regulation. Among these samples, 1615 people (male 824, female 791) received blood-lipid analysis. RESULTS: The hypertensive incidence of Heilongjiang was much higher than the average level in China (P < 0.01) and it has gotten higher from 1959 to 1999, especially in the last ten years. It increased more in males than in females (P < 0.01). It was also higher with age. The mean age of hypertensive onset became ten years younger recently. It is different in different areas and professions. Age, BMI (body mass index), drinking alcohol, gender, history of maternal hypertension, high salt diet and professional status were the main risk factors for hypertension in Heilongjiang Province in China. CONCLUSION: The prophylaxis and treatment of hypertension should be enhanced in this area.

[Epidemiological study of hypertension in Heilongjiang province].

OBJECTIVE: To find out the epidemiological features of hypertension in Heilongjiang Province, so as to provide guidance and scientific ebidence for hypertensive prophylaxis and treatment. METHODS: >From the year of 1959 to 1999, 289 157 people in total with age >/= 15 years old (male 154 091, female 135 066) were investigated with stratified chunk method in rural and urban areas in Heilonging Province. RESULTS: Hypertensive incidence in Heilongjiang is much higher than the average level in China (P < 0.01). Hypertensive incidence has become higher and higher during the 40 years it increased 105%. It is in the recent ten years that hypertensive incidence increased most fast. Hypertensive incidence increased more obviously in male than in female (P < 0.01). Hypertensive incidence also increased with aging. Hypertensive incidence has increased both in urban and rural areas, with the urban incidence higher than rural (P < 0.01). Blood lipids (TC, TG, LDL-C, VLDL-C) of the subjects receiving this analysis in the year of 1999 was much higher than those in 1985 (P < 0.01). Alcohol drinking is related to hypertension (OR = 2.18). Smoking is also related to hypertension (OR = 1.29). People with body mass index (BMI) >/= 20 had higher hypertensive incidence (17.56%) than those with BMI < 20 (7.69%). 39 possible related factors of hypertension were analyzed; it is shown that profession of cadre, high BMI, alcohol drinking, male gender, mother's history of hypertension high salt diet and old age are the main risk factors of hypertension. CONCLUSION: The programs of prophylaxis and treatment of hypertension should be enhanced in this province.