Dagmar Solichová

Intestinal permeability in patients with chemotherapy-induced stomatitis.

Purpose: Mucositis represents one of the most common side effects of chemotherapy, and may affect any part of the gastrointestinal tract, resulting in stomatitis, dysphagia, dyspepsia, or diarrhea. The aim of the present study was to evaluate intestinal permeability in patients with stomatitis during treatment with oral granulocyte-monocyte colony-stimulating factor (GM-CSF, Leucomax). Methods: Ten patients with chemotherapy-induced stomatitis and 21 control cancer patients were included in the study. Intestinal permeability in patients with stomatitis was evaluated before and after the treatment with oral GM-CSF (200 μg for 4 consecutive days) by measuring urinary lactulose, D-xylose, and mannitol after oral challenge in collected urine using capillary gas chromatography. Results: Mean grade of stomatitis (3, range 2–3) improved during treatment by a mean of 1 grade (range 0–2, sign test P < 0.05) with an improvement observed in eight of ten patients. Lactulose excretion, lactulose/mannitol, and lactulose/xylose ratios were markedly elevated in the patients with mucositis compared with 21 control cancer patients (1.60 ± 1.04%, 0.2446 ± 0.2937, and 0.3877 ± 0.6808 vs 0.35 ± 0.20%, 0.0332 ± 0.0148, and 0.0255 ± 0.0086, respectively, Mann Whitney U-test, P < 0.001). After treatment, lactulose excretion, lactulose/mannitol, and lactulose/xylose ratio decreased significantly (1.60 ± 1.04 vs 0.63 ± 0.42%; 0.2446 ± 0.2937 vs 0.1303 ± 0.1149; and 0.3877 ± 0.6808 vs 0.1126 ± 0.1146, respectively, P < 0.05). Conclusions: Lactulose excretion after oral challenge, lactulose/mannitol, or lactulose/xylose ratio may be useful markers for intestinal involvement in chemotherapy-induced mucositis. Improvement of oral mucositis was associated with a significant decrease of intestinal permeability to lactulose. Testing of intestinal permeability by the present method may be useful to evaluate the effect of therapeutic interventions in patients with chemotherapy-induced mucositis.

Ultra high performance liquid chromatography tandem mass spectrometric detection in clinical analysis of simvastatin and atorvastatin.

Simvastatin and atorvastatin belong to the group of hypolipidemic drugs, more exactly to the second generation of inhibitors of microsomal 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. They induce a significant reduction in total cholesterol, low-density lipoprotein cholesterol and plasma triglycerides, therefore they are widely used in the treatment of hypercholesterolemia even of its severe form-familiar hypercholesterolemia. Simvastatin and atorvastatin as the most widely used statins in clinical treatment and their hydroxy-acid/lactone forms were determined by means of UPLC in connection with triple quadrupole mass spectrometer. Deuterium labeled reference standard compounds were used as internal standards for the quantitation. Separation was performed on Acquity BEH C18 (100 mm x 2.1 mm, 1.7 microm) using gradient elution by mobile phase containing acetonitrile and ammonium acetate pH 4.0, which is convenient in order to prevent interconversion of analytes. ESI in positive mode was used for the ionization of all compounds. Two SRM (selected reaction monitoring) transitions were carefully optimized for each analyte in order to get high sensitivity and selectivity. SPE on Discovery DSC-18 was used as a sample preparation step. Intra-day precision was generally within 10% RSD, while inter-day precision within 15% RSD. Method accuracy expressed as recovery ranged from 75 to 100%. The method was validated with the sensitivity reaching LOQ 0.08-5.46 nmol/l and LOD 0.01-1.80 nmol/l in biological samples. Atorvastatin, simvastatin, its metabolites and hydroxy-acid/lactone forms were monitored in human serum and in lipoprotein fractions (LDL, HDL and VLDL) at patients with end stage renal diseases.

Microextraction by packed sorbent as sample preparation step for atorvastatin and its metabolites in biological samples—Critical evaluation

Atorvastatin belongs to the group of lipid-lowering drugs known as statins. They significantly reduce the levels of total cholesterol, low-density cholesterol and plasma triglycerides therefore they are widely used in the treatment of hypercholesterolemia. Recently developed methods for the determination of atorvastatin and its metabolites in plasma used SPE (solid phase extraction) or LLE (liquid-liquid extraction) as the sample preparation step. However, both procedures are quite time-consuming and need relatively high volume of solvent/sample, which is impractical for the routine analyses of many biological samples. The aim of this work was to develop and validate more suitable sample preparation method for the determination of atorvastatin and its metabolites in biological samples using MEPS (microextraction by packed sorbent). The optimal conditions of MEPS extraction were using C8 sorbent and only 50 μl of the sample. The analytes were eluted by 100 μl of the mixture of acetonitrile:0.1 M ammonium acetate pH 4.5 (95:5, v:v). The analytical method was validated and demonstrated good linearity (r(2)>0.9990), recovery (89-115%) and intra-day precision (RSD<10%). Total time of the sample preparation was three times shorter (7 min) compared to SPE. The volume of sample was twenty times lower and the volume of solvents about ten times lower compared to SPE. Combination of fast MEPS method together with quick UHPLC-MS/MS was used for the determination of atorvastatin and its two metabolites in serum obtained from patients with familiar hypercholesterolemia.

Biochemical profile and survival in nonagenarians

OBJECTIVES Old age is associated with an increase in frequency of disorders involving virtually all organ systems, resulting in a rise of mortality. The aim of the project was to study the relationship between biochemical markers and all-cause mortality in a defined age group. DESIGN AND METHODS Thirty-eight nonagenarians, aged 92 +/- 2 (range 90-100) years entered the study. At the start of the study, a sample of peripheral blood and urine were obtained for analysis of 50 basic biochemical, hematologic and biologic parameters. The assessment was then repeated in 6 to 12 months intervals. The significance of difference between surviving subjects and those who died was examined by Mann-Whitney U test and the correlation between the variables was studied by Spearman rank correlation coefficient. RESULTS During the observation period, 21 of the studied subjects died leaving 17 persons still alive at the end of the study. The mean time from the first measurement to the death was 12 +/- 10 (range 0-33) months. The mean follow-up time in surviving subjects was 31 +/- 12 (range 4-45) months. Serum vitamin E and calcium were significantly higher, and serum alanine aminotransferase (ALT) and urinary neopterin were significantly lower in survivors compared to the subjects who died. No other parameters were significantly different in survivors and in persons who died. Urinary neopterin exhibited a significant negative correlation with serum sodium concentration (RS = -0.50, p < 0.01), but the other parameters did not correlate significantly. CONCLUSION In conclusion, among the parameters studied, differences between survivors and nonsurvivors were observed only for serum vitamin E, calcium, ALT and urinary neopterin. These findings may form a basis for prospective interventional trials in this group of patients.

Hydrophilic interaction liquid chromatography - charged aerosol detection as a straightforward solution for simultaneous analysis of ascorbic acid and dehydroascorbic acid.

Ascorbic acid (AA) and dehydroascorbic acid (DHA) are small polar molecules difficult to be retained in conventional chromatographic RP systems. Hydrophilic interaction liquid chromatography (HILIC) using Obelisk R (100 x 3.2mm, 5 microm, Sielc) analytical column and isocratic elution by ammonium acetate buffer pH 4.2 was found to be successful at this task, while other tested HILIC columns--Obelisk N (100 x 3.2mm, 5 microm, Sielc) and Luna HILIC (100 x 3.0mm, 3 microm, Phenomenex) were unsuccessful for the purposes of analysis. Charged aerosol detection (CAD) has recently become a new alternative universal detection system in HPLC, and was extremely convenient for the simultaneous analysis of AA and DHA without the need of subtraction approach and oxidation/reduction step. CAD response was found linear in defined range in spite of the fact that CAD is designated as non-linear detection method. A simple and fast HILIC-CAD method was applied for the analysis of pharmaceutical preparations containing AA. Method validation was performed including parameters of precision, accuracy, linearity, limit of detection and limit of quantitation (LOQ). The method was fast, accurate and precise for both detectors with LOQ(AA) 5 microg/ml for UV detection and 10 microg/ml for CAD, respectively. DHA was detected only by CAD within tested concentration range with LOQ(DHA) 1 microg/ml.

Comparison of UV and charged aerosol detection approach in pharmaceutical analysis of statins

CAD (charged aerosol detector) has recently become a new alternative detection system in HPLC. This detection approach was applied in a new HPLC method for the determination of three of the major statins used in clinical treatment-simvastatin, lovastatin and atorvastatin. The method was optimized and the influence of individual parameters on CAD response and sensitivity was carefully studied. Chromatography was performed on a Zorbax Eclipse XDB C18 (4.6 mm x 75 mm, 3.5 microm), using acetonitrile and formic acid 0.1% as mobile phase. The detection was performed using both CAD (20 pA range) and DAD (diode array detector-238 nm) simultaneously connected in series. In terms of linearity, precision and accuracy, the method was validated using tablets containing atorvastatin and simvastatin. The CAD is designated to be a non-linear detector in a wide dynamic range, however, in this application and in the tested concentration range its response was found to be perfectly linear. The limits of quantitation (0.1 microg/ml) were found to be two times lower than those of UV detection.

Urinary neopterin in patients with advanced colorectal carcinoma.

In previous studies, mostly in patients with early stage colorectal carcinoma, neopterin, an indicator of systemic immune activation, has been associated with poor prognosis. The aim of the present study was to evaluate urinary neopterin in patients with advanced or metastatic colorectal carcinoma treated with chemotherapy. A retrospective analysis was performed of urinary neopterin, determined by high-performance liquid chromatography, in 88 patients with advanced or metastatic colorectal carcinoma. Peripheral blood cell count and serum carcinoembryonic antigen (CEA) were determined in 72 patients before the start of chemotherapy. Urinary neopterin in colorectal carcinoma patients was significantly increased compared to controls, but lower than in patients with inflammatory bowel disease. Neopterin correlated significantly with serum CEA, age, peripheral blood leukocyte and platelet counts. The median survival of colorectal carcinoma patients with urinary neopterin below 214 mol/mol creatinine was significantly longer compared to that of patients with higher neopterin concentrations (median 18 vs 5 months, log-rank test p=0.003). CEA and hemoglobin were also associated with survival in univariate analysis, but in multivariate analysis only urinary neopterin and serum CEA were independent predictors of survival. High urinary neopterin during follow-up was also predictive of poor prognosis.

Atorvastatin has hypolipidemic and anti-inflammatory effects in apoE/LDL receptor-double-knockout mice

Statins are first-line pharmacotherapeutic agents for hypercholesterolemia treatment in humans. However the effects of statins in animal models of atherosclerosis are not very consistent. Thus we wanted to evaluate whether atorvastatin possesses hypolipidemic and anti-inflammatory effects in mice lacking apolipoprotein E/low-density lipoprotein receptor (apoE/LDLR-deficient mice). Two-month-old female apoE/LDLR-deficient mice (n=24) were randomly subdivided into 3 groups. The control group of animals (n=8) was fed with the western type diet (atherogenic diet) and in other two groups atorvastatin was added to the atherogenic diet at the dosage of either 10 mg/kg or 100 mg/kg per day for a period of 2 months. Biochemical analysis of lipids, ELISA analysis of monocyte chemotactic protein-1 (MCP-1) in blood, quantification of lesion size and expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) in the atherosclerotic lesion by means of immunohistochemistry and Western blot analysis were performed. The biochemical analysis showed that administration of atorvastatin (100 mg/kg/day) significantly decreased level of total cholesterol, lipoproteins (VLDL and LDL), triacylglycerol, and moreover significantly increased level of HDL. ELISA analysis showed that atorvastatin significantly decreased levels of MCP-1 in blood and immunohistochemical and Western blot analysis showed significant reduction of VCAM-1 and ICAM-1 expression in the vessel wall after atorvastatin treatment (100 mg/kg/day). In conclusion, we demonstrated here for the first time strong hypolipidemic and anti-inflammatory effects of atorvastatin in apoE/LDLR-deficient mice. Thus, we propose that apoE/LDLR-deficient mice might be a good animal model for the study of statin effects on potential novel markers involved in atherogenesis and for the testing of potential combination treatment of new hypolipidemic substances with statins.

Cd4+ T-lymphocytopenia and systemic immune activation in patients with primary and secondary liver tumours

Using flow cytometry, we evaluated peripheral blood leucocyte subsets in 84 patients with primary and secondary liver cancer. The patients had significantly lower absolute (659+/-386 vs. 906+/-360 cells per microl, p=0.004) numbers of CD3+ CD4+, relative (9+/-5 vs. 12+/-4%, p=0.02) and absolute (154+/-115 vs. 221+/-83 cells per microl, p=0.02) numbers of CD8+ CD28+, absolute numbers of CD3+ and relative and absolute numbers of CD19+. Relative and absolute numbers of CD3+ DR+, CD3+ CD69+ and CD14+ CD16+ cells were significantly elevated in patients compared to controls. The phenotype was similar in 54 patients exposed to chemotherapy compared to 30 untreated patients. Urinary neopterin, a marker of systemic immune activation, was significantly higher in patients with liver tumours compared to controls. A negative correlation was observed between urinary neopterin and the absolute numbers of CD3+ CD4+ (Spearman rank correlation coefficient, rs = -0.54, p<0.0025) and CD19+ (rs = -0.49, p<0.01) in untreated patients. We conclude that, independently of prior chemotherapy, patients with liver present with markedly decreased numbers of CD3+ CD4+ lymphocytes as well as with other abnormalities of peripheral blood leukocyte phenotype. Similar to patients with human immunodeficiency virus infection, the decrease in CD3+ CD4+ lymphocytes is associated with systemic immune activation.

The changes in the endothelial expression of cell adhesion molecules and iNOS in the vessel wall after the short-term administration of simvastatin in rabbit model of atherosclerosis

Cell adhesion molecules P‐selectin, VCAM‐1 and ICAM‐1 play an important role in the pathogenesis of atherosclerosis. High levels of nitric oxide (NO) produced by inducible NO synthase (iNOS) have been associated with atherosclerotic processes. Simvastatin is an HMG‐CoA reductase inhibitor responsible for many clinical benefits. The aim of this study was to detect and quantify changes in endothelial expression of P‐selectin, VCAM‐1, ICAM‐1 and iNOS in the vessel wall after the short‐term administration of simvastatin in a rabbit model of atherosclerosis. Eighteen New Zealand White rabbits were randomly divided into three groups (n = 6). In the cholesterol group, rabbits consumed an atherogenic diet (0.4% cholesterol) for eight weeks. In the simvastatin group, rabbits consumed an atherogenic diet for six weeks and then consumed an atherogenic diet supplemented with simvastatin (10 mg kg−1) for two weeks. Biochemical analysis showed that administration of simvastatin led to an almost two‐fold lowering of the total serum cholesterol, VLDL, LDL and HDL, but not triglycerides, compared with the cholesterol‐fed rabbits only. Stereological analysis of the immuno‐histochemical staining revealed that administration of simvastatin (10 mg kg−1 daily) in an atherogenic diet decreased the endothelial expression of P‐selectin, ICAM‐1 and iNOS in both aortic arch and carotid artery compared with the cholesterol fed‐rabbits only. We conclude that simvastatin has beneficial effects on endothelial function by decreasing expression of P‐selectin, ICAM‐1 and iNOS in endothelial cells in the very early stages of atherogenesis.