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Donata Scribano

Publications and source records attributed to Donata Scribano.

4 recordsLinked to original sources

Analytical evaluation of a new immunonephelometric method for homocysteine measurement.

BACKGROUND AND OBJECTIVES: Increased plasma homocysteine, a sulphur amino acid closely related to methionine metabolism, is considered an independent risk factor for cardiovascular diseases. Over the last years, the request to clinical laboratories for homocysteine measurement is constantly increased and, for this reason, several new methods have been developed, mainly with the aim of using them on completely automated instruments for routine analyses. In this paper, we evaluated a new immunonephelometric method for homocysteine determination on the Dade Behring BNII nephelometer. METHODS: Linearity, recovery, limit of detection (LOD) and total imprecision and were assessed; moreover, the method was compared with a HPLC reference method and with an automated immunoassay method (AxSYM Abbott). RESULTS: Recovery range was 96.4-104.2%, LOD was 0.5 micromol/L and total imprecision ranged from 5.0% to 7.6%. For the comparison study, the immunonephelometric method showed a good correlation both with HPLC (Y=1.02X-0.79, R(2)=0.99) and with the AxSYM method (Y=1.003X+0.06, R(2)=0.98). The Bland-Altman plot analysis shows that the immunonephelometric method has a slight positive bias with both HPLC (mean: 1.03 micromol/L, 95% confidence interval: 0.28-1.79 micromol/L) and AxSYM methods (mean: 0.45 micromol/L, 95% confidence interval: -0.03-0.94 micromol/L). CONCLUSION: The new nephelometric method from Dade Behring, for its analytical performance, can be easily considered a suitable method for homocysteine routine measurement; moreover, it cannot be ruled out that the widespread availability of nephelometers in clinical laboratories play a leading role in the choice of this method.

Adenosylhomocysteinase↗

Evaluation of a new enzymatic method for homocysteine measurement.

BACKGROUND AND OBJECTIVES: The increased need in clinical chemistry laboratories for methods of homocysteine determination, in correlation with cardiovascular diseases and nutritional deficient status, has led to the development of different analytical methods; fluorescent immunoenzymatic assays and, recently, new fully automated spectrophotometric methods are commercially available. In this paper, we compared data obtained from a new enzymatic method for homocysteine assay (Carolina Liquid Chemistries), with data obtained from a HPLC reference method and an immunoenzymatic method (Abbott AxSYM immunoassay). RESULTS: The enzymatic method shows a good correlation with both the HPLC (Y = -1.3 + 1.02X; R2 = 0.93) and the immunoenzymatic method (Y = 0.7 + 1.02X; R2 = 0.92), although a bias enhancement was present in some samples. However, the enzymatic method shows a superior analytical feasibility because it needs only common laboratory instruments (UV-visible spectrophotometer) and can be easily adapted to large automatic clinical chemistry analyzers. Moreover, it lowers the laboratory cost of the analysis in comparison to both HPLC and immunoenzymatic methods. CONCLUSIONS: The enzymatic Carolina Liquid Chemistries method for homocysteine assay shows acceptable analytical performance and undoubtedly possesses technical and cost advantages.

Adult↗

HPLC analysis of some sulphur compounds in saliva: comparison between healthy subjects and periodontopathic patients.

BACKGROUND: Saliva is an easily available biological material that is not commonly analysed in clinical chemistry, while it could give useful information especially in several oral diseases. METHODS: In this work, the sulphur containing compounds cysteine, cysteinylglycine and glutathione were analysed in saliva of control subjects and periodontopathic subjects by a HPLC method. The detection limit of the method is 0.5, 0.1 and 0.1 micromol/l for cysteine, cysteinylglycine and glutathione, respectively, and it is linear up to 10 mmol/l. RESULTS: the median values for the control group are 1.2 micromol/l for cysteine and glutathione and 0.4 micromol/l for cysteinylglycine while those of periodontopathic patients are significantly increased (4.4, 2.1 and 11.0 micromol/l for cysteine, cysteinylglycine and glutathione, respectively).

Adult↗

Comparing different methods for homocysteine determination.

Slightly elevated values of homocysteine are commonly associated with thromboembolic diseases, while high values can be found in patients with congenital metabolic defects or nutritional problems. The clinical use of homocysteine as an independent marker of cardiovascular disease was limited in the past by technical problems with its measurement, the instrumentation (HPLC, radioenzymatic assays, gas chromatography-mass spectrometry, etc.) and the necessary skills required. Commercially available immunoassays now permit a simpler and more rapid measurement of homocysteine, that is more suitable for routine clinical laboratories; in this paper we analyze the results obtained by using three fully automated methods for homocysteine determination (Abbott IMx immunoassay, Abbott AxSYM immunoassay and Immulite 2000 homocysteine immunoassay) and their correlation with the widely used HPLC method. The results clearly indicate that all three automated immunochemical methods correlate well with the HPLC method (slope 0.97-1.03; intercept 0.95-1.91 with a recovery above 95% for all three methods).

Adolescent↗