Reduction capacity ( RC ) is an important index to evaluate the redox ability of dissolved organic matter. In order to determine the RC, hydrophilic organic fractions ( HyI ) isolated from dissolved organic matter extracted from the uncomposted and composted samples were used as electron donators and mediators, and three kinds of irons were chosen as electron acceptors. The results showed that, the RC values from the composted sample were 15. 88, 13. 41 and 51. 45 mmol e -/mol C for the electron acceptors Fe2(SO4)3, Fe(NO3)3 and FeCit, respectively, which were higher than the corresponding values (13. 45, 11. 77 and 43. 16 mmol e-/mol C) from the uncomposted sample. The electron acceptor type shows a dramatic influence on the RC value of HyI. The RC value determined by FeCit was obviously higher than that measured using Fe2( SO4 ) 3 and Fe( NO3 ) 3 , and the microbial reducing capacity of the HyI was lower than the corresponding native reducing capacity. By analyzing the special absorbencies ( SUVA254 and SUVA280 ) , absorbance ratios ( A2/A3 and A4/A6 ) and integrated area from UV-vis spectra, it can be found that the RC was affected by aromatic degree, unsaturated conjugated structure, and molecular weight. Excitation-emission matrix spectra coupled with regional integration analysis showed that the relative content of humic-like substances ( humic-like acids and fulvic-like acids) was the main factor influencing the RC value of HyI. The results obtained can be used to characterize the redox properties of HyI, and reveal its role in the transformation and degradation of pollutants during composting.

Objective To analyze the clinical features of takayasu's arteritis in elderly patients for improving their general management.Methods Twenty-six patients,aged over 60 years,with takayasu's arteritis were enrolled.The clinical manifestations and medical records were collected in detail and analyzed retrospectively.Results The mean age of the patients in our study was 64.0±3.8 years,four males and twenty-two females.Of all patients,nine were accompanied by coronary heart disease,seven by primary hypertension,four by diabetes mellitus,two by arrhythmia and one by subacute infective endocarditis.The frequent clinical manifestations were hypertension (n = 21,81%),dizzy (n=12.46%),chest pain (n=9,35%),pulselessness or weak pulse (n=7,27%).The clinical classification of this group showed brachiocephalic artery type (n = 8,30%),abdominal aorta type (n=4,15%),extensive type (n=11,58%) and pulmonary artery type (n=3,12%).Ten patients had elevated ESR level,six had elevated CRP level and fourteen had elevated ASO level.Two patients with diabetes mellitus died of serious complications.Conclusions Takayasu's arteritis in the elderly is usually accompanied by other cardiovascular diseases and risk factors.It is important to enhance the comprehensive treatment of these patients.

Objective To evaluate the safety and clinical efficacy of renal artery stent treatment for severe atherosclerotic renal artery stenosis (ARAS) in the elderly. Methods In a prospective nonrandomized study in our hospital from January 2003 to April 2008, 147 consecutive elderly patients with ARAS (diameter reduction ≥ 65％) underwent percutaneous transluminal renal angioplasty and stenting (PTRAS) for resistant hypertension or reserving renal function. They were followed up for 6- 66 months and the effects of the procedure on renal function, blood pressure and cardiovascular events were observed. Results The success rate of PTRAS was 100％. During 6-66 months of follow up, both systolic and diastolic blood pressure were significantly decreased, and less antihypertensive medication was taken (P<0.01). Serum creatinine was significantly decreased during 6-48 months of follow up (P<0. 05) and did not change significantly during 54-66 months of follow up (P>0. 05). Blood urea nitrogen was significantly decreased during 6-24 months of follow up (P<0.05) and did not change significantly during 30-66 months of follow up (P>0.05). Complications related with the procedure occurred in 7 cases (4.8％). 17 patients failed to follow up (11.6％) and in 18 cases cardiovascular events occurred (12.2％), including 4 cases of renal events (2. 7％), 4 cases of myocardial infarction (2.7％), 2 cases of stroke (1.4％) and 8 cases of cerebral and cardiovascular events (5.4％) during 6-66 months of follow up. The survival rates of free-of-events at year 1, 2, 3, 4 and5 were 91.0%(121/133), 90.2%(83/92), 78.5%(51/65), 73.8%(31/42) and 54.8%(17/ 31), respectively. The survival rates at year 1, 2, 3, 4 and 5 were 94.0% (125/133), 90. 2% (83/ 92), 84.6%(55/65), 73. 8%(31/42) and 61.3%(19/31), respectively. Conclusions Renal artery stent as treatment for ARAS in the elderly has a beneficial effect on blood pressure control and on renal function during middle and long term follow up. The treatment may be helpful in reduction of cardiovascular events and mortality, which should be investigated further.