New HPLC method for the determination of vitamins K , MK-4, and MK-7 in serum was evaluated and validated. This method is highly specific and sensitive with the low limit of quantification.
A novel application of the liquid chromatography method combined with the triple quadrupole tandem mass spectrometry method was developed for the quantification of vitamin K1 and two forms of vitamin K2 (menaquinone-4, menaquinone-7) in human serum. Total chromatography time for each run was 9 min. Time required for the sample pretreatment procedures was approximately 4 h. The coefficients of variation (CVs) of intra-assay were 10.4%, 3.2 % and 2.3% for vitamin K1 in three levels of quality control samples; were 14.3%, 3.2% and 6.7% for menaquinone-4; and were 11.1%, 6.0% and 7.0% for menaquinone-7. The inter-assay CVs were 12.8%, 11.3% and 7.4% for vitamin K1; were 15.2%, 9.2% and 8.7% for menaquinone-4; and were 13.2%,11.1% and 7.2% for menaquinone-7. No interference was found between K1, menaquinone-4 and menaquinone-7, nor any deuterated internal standards. This method was then used to determine reference values for Caucasian populations of central European origin. Samples were measured from 191 healthy volunteers (51.2 ± 16.2 years (mean ± SD)) and the values concerning K1 were 0.044–1.357 ng/mL for women and 0.030–1.214 ng/mL for men. The values for menaquinone-4 and menaquinone-7 did not exhibit any differences between women and men, and were 0.050–1.598 and 0.074–0.759 ng/mL, respectively.
Selenium (Se) is an essential trace element with antioxidant function. The aim of the present study was to estimate the alterations of Se serum level during the acute phase of myocardial infarction and its relation to biomarkers of myocardial necrosis. Serum Se levels were measured at admission and after 24 h in 60 consecutive patients with acute coronary syndrome (both with and without ST elevation). Troponin I (TnI) was assessed at admission and then twice daily for 3 days; patients with normal levels were excluded. Fifty-five patients with acute MI (positive TnI) were included into the analysis. During the first day of hospitalization, patients received standard therapy, including acetylsalicylic acid, clopidogrel, and heparin or enoxaparin; all underwent urgent coronary angiography and percutaneous intervention, when appropriate. Mean Se levels at baseline and 24 h later were comparable (67.1 ± 2.1 vs. 67.2 ± 1.8 μg/L, ns). Linear regression has shown significant correlation between baseline Se levels and peak TnI (y = 3.4x - 116, r (2) = 0.13, P = 0.008). Positive correlation was found also between the peak TnI and the difference from baseline to 24 h (y = 2.2x + 115, r (2) = 0.08, P = 0.04). Moreover, close negative correlation was observed between baseline Se levels and the difference from baseline to 24 h (y = -0.9x + 62.7, r (2) = 0.55, P<0.001). Our results have shown marked individual changes in Se levels during the acute phase of MI as well as correlation between Se levels and peak TnI. These results suggest that alterations in serum Se may be related to the extent of myocardial infarction.
BackgroundStatins have been proved to be effective in reduction of mortality and morbidity when started in the early secondary prevention in stabilized patients after acute coronary syndrome (ACS). The safety and efficacy of statin administration directly in the first-line therapy in unstable ACS patients is not clear. The aim of our study was, therefore, to assess the effect of statin treatment initiated immediately at hospital admission of patients with ACS.MethodsThe trial was stopped prematurely after enrollment of one hundred and fifty-six patients with ACS that were randomized at admission to fluvastatin 80 mg (N = 78) or placebo (N = 78). Study medication was administered immediately after randomization and then once daily for 30 days; all patients were then encouraged to continue in open-label statin therapy and at the end of one-year follow-up 75% in the fluvastatin group and 78% in the placebo group were on statin therapy.ResultsWe did not demonstrate any difference between groups in the level of C-reactive protein, interleukin 6, and pregnancy-associated plasma protein A on Day 2 and Day 30 (primary endpoint). Fluvastatin-therapy, however, significantly reduced one-year occurrence of major adverse cardiovascular events (11.5% vs. 24.4%, odds ratio (OR) 0.40, 95% CI 0.17-0.95, P = 0.038). This difference was caused mainly by reduction of recurrent symptomatic ischemia (7.7% vs. 20.5%, OR 0.32, 95% CI 0.12-0.88, P = 0.037).ConclusionsThis study failed to prove the effect of fluvastatin given as first-line therapy of ACS on serum markers of inflammation and plaque instability. Fluvastatin therapy was, however, safe and it may reduce cardiovascular event rate that supports immediate use of a statin in patients admitted for ACS.Trial registrationNCT00171275
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