Prevalence and risk factors for vascular calcification in Chinese patients receiving dialysis: baseline results from a prospective cohort study.

OBJECTIVE: With limited data available on calcification prevalence in chronic kidney disease (CKD) patients on dialysis, the China Dialysis Calcification Study (CDCS) determined the prevalence of vascular/valvular calcification (VC) and association of risk factors in Chinese patients with prevalent hemodialysis (HD) or peritoneal dialysis (PD). METHODS: CKD patients undergoing HD/PD for ≥6 months were enrolled. Prevalence data for calcification and medical history were documented at baseline. Coronary artery calcification (CAC) was assessed by electron beam or multi-slice computed tomography (EBCT/MSCT), abdominal aortic calcification (AAC) by lateral lumbar radiography, and cardiac valvular calcification (ValvC) by echocardiography. Serum phosphorus, calcium, intact parathyroid hormone (iPTH), and 25-hydroxyvitamin D and FGF-23 were evaluated. A logistic regression model was used to evaluate the association between risk factors and VC. RESULTS: Of 1,497 patients, 1,493 (78.3% HD, 21.7% PD) had ≥1 baseline calcification image (final analysis cohort, FAC) and 1,423 (78.8% HD, 21.2% PD) had baseline calcification data complete (BCDC). Prevalence of VC was 77.4% in FAC (80.8% HD, 65.1% PD, p < .001) and 77.5% in BCDC (80.7% HD, 65.8% PD). The proportion of BCDC patients with single-site calcification were 20% for CAC, 4.3% for AAC, and 4.3% for cardiac valvular calcification (ValvC), respectively. Double site calcifications were 23.4% for CAC and AAC, 6.5% for CAC and ValvC, and 1.1% for AAC and ValvC, respectively. In total, 17.9% patients had calcification at all three sites. CONCLUSIONS: High prevalence of total VC in Chinese CKD patients will supplement current knowledge, which is mostly limited, contributing in creating awareness and optimizing VC management.

[Qualitative Determination of Organic Vapour Using Violet and Visible Spectrum].

Vapours of organic matters were determined qualitatively employed with ultraviolet-visible absorption spectroscopy. Vapours of organic matters were detected using ultraviolet-visible spectrophotometer employing polyethylene film as medium, the ultraviolet and visible absorption spectra of vegetable oil vapours of soybean oil, sunflower seed oil, peanut oil, rapeseed oil, sesame oil, cotton seed oil, tung tree seed oil, and organic compound vapours of acetone, ethyl acetate, 95% ethanol, glacial acetic acid were obtained. Experimental results showed that spectra of the vegetable oil vapour and the organic compound vapour could be obtained commendably, since ultra violet and visible spectrum of polyethylene film could be deducted by spectrograph zero setting. Different kinds of vegetable oils could been distinguished commendably in the spectra since the λ(max), λ(min), number of absorption peak, position, inflection point in the ultra violet and visible spectra obtained from the vapours of the vegetable oils were all inconsistent, and the vapours of organic compounds were also determined perfectly. The method had a good reproducibility, the ultraviolet and visible absorption spectra of the vapours of sunflower seed oil in 10 times determination were absolutely the same. The experimental result indicated that polyethylene film as a kind of medium could be used for qualitative analysis of ultraviolet and visible absorption spectroscopy. The method for determination of the vapours of the vegetable oils and organic compounds had the peculiarities of fast speed analysis, well reproducibility, accuracy and reliability and low cost, and so on. Ultraviolet and visible absorption spectrum of organic vapour could provide feature information of material vapour and structural information of organic compound, and provide a novel test method for identifying vapour of compound and organic matter.