Biomedical subjects

Pasquale De Sole

Publications and source records attributed to Pasquale De Sole.

6 recordsLinked to original sources

PubMed2006

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↗

PubMed2005

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↗

PubMed2004

Mitochondrial respiratory chain dysfunction, a non-receptor-mediated effect of synthetic PPAR-ligands: biochemical and pharmacological implications.

Peroxisome proliferator activated receptors (PPARs) are a class of nuclear receptors involved in lipid and glucidic metabolism, immune regulation, and cell differentiation. Many of their biological activities have been studied by using selective synthetic activators (mainly fibrates and thiazolidinediones) which have been already employed in therapeutic protocols. Both kinds of drugs, however, showed pharmacotoxicological profiles, which cannot be ascribed by any means to receptor activation. To better understand these non-receptorial or extrareceptorial aspects, the effect of different PPAR-ligands on the metabolic status of human HL-60 cell line has been investigated. At this regard, NMR analysis of cell culture supernatants was accomplished in order to monitor modifications at the level of cell metabolism. Cell growth and chemiluminescence assays were employed to verify cell differentiation. Results showed that all the considered PPAR-ligands, although with different potencies and independently from their PPAR binding specificity, induced a significant derangement of the mitochondrial respiratory chain consisting in a strong inhibition of NADH-cytochrome c reductase activity. This derangement has been shown to be strictly correlated to the adaptive metabolic modifications, as evidenced by the increased formation of lactate and acetate, due to the stimulation of anaerobic glycolysis and fatty acid beta-oxidation. It is worthy noting that the mitochondrial dysfunction appeared also linked to the capacity of any given PPAR-ligand to induce cell differentiation. These data could afford an explanation of biochemical and toxicological aspects related to the therapeutic use of synthetic PPAR-ligands and suggest a revision of PPAR pathophysiologic mechanisms.

Bezafibrate↗

PubMed2003

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↗

PubMed2002

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↗

PubMedDate not supplied

Alteration of monocytic cell oxidative burst caused by methacrylic monomers present in dental materials: a chemiluminescence study.

Methacrylates are present in dental composite resins used in clinical practice. Methacrylates are photo-polymerized, but this reaction is never complete, so release of uncured monomers in the periapical tissues and in biological fluids may happen and, potentially, alter the repair of pulpal and of periapical lesions by interfering with local phagocytes. The aim of this study was the evaluation of the functional activity of the monocyte-macrophage system after incubation with methacrylic monomers. The oxidative burst of two cellular systems was analysed using the chemiluminescence technique. Data were collected and statistically analysed. Monomers were found to reduce the in vitro oxidative burst of phagocytes independently from their cytotoxicity. These findings demand further evaluation of the effects of oxidative burst alteration in monocyte-macrophage function and may prompt the inclusion of the described chemiluminescence test in biocompatibility preliminary studies of dental materials.

Cell Survival↗