The usefulness of monitored therapy using Clozapine concentration in the blood serum for determining drug dose in Polish schizophrenic patients.

BACKGROUND: The aim of the study is to evaluate the advisability of systematic monitoring of clozapine (CLO) concentration in serum during treatment of schizophrenia in Polish psychiatric patients. METHOD: The concentration of CLO and its metabolites: norclozapine (NCLO) and clozapine N-oxide (CLO-NO) in serum obtained from 107 patients suffering from schizophrenia was determined by high performance liquid chromatography (HPLC) method. There were two groups of patients. In the first group of patients (n=95) the concentration of drug and its metabolites was determined by one-time testing. Correlations were tested using the test statistics. In the second group of patients (n=12), 51 samples of serum were provided by the same patient in different time spans (from 6days to 14 months after the beginning of the treatment). RESULTS: Concentrations of CLO and its metabolites in blood serum do not always show a linear dependence on the applied dose for individual patients. CONCLUSION: The high volatility of CLO concentrations in blood serum of patients treated with identical doses of the drug confirmed the validity of the monitored therapy.

Serum cortisol concentration in patients with major depression after treatment with fluoxetine.

Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and elevated cortisol levels is characteristic of the pathophysiology of major depressive disorder (MDD). The aim of this study was to determine whether increased plasma cortisol levels appear in patients with major depression and if effective antidepressant treatment by fluoxetine leads to regulation of cortisol level. This aim was realized by describing and validation of methods of determining fluoxetine and cortisol in serum and searching for correlation between their concentrations in patients with endogenous depression, the therapeutic effect as assessed in Hamilton Depression Rating Scale (HDRS), age and sex of patients. Plasma cortisol and fluoxetine levels were measured using high performance liquid chromatography (HPLC) methods with applying Shimadzu chromatograph with UV detection. Plasma cortisol and fluoxetine levels were measured at time zero (before therapy) and after 6h, 24h, 2, 4, 6 and 8 weeks of fluoxetine administration in patients with major depression qualified for therapeutic drug monitoring (TDM). The study included 21 patients (14 women, 7 men; mean age 29-75 years) and 24 healthy comparison subjects. The patients had a mean score on the 21-item HDRS. As the effect of fluoxetine administration the decrease of the level of cortisol was observed in patients who responded to the therapy (the reduction of points in HDRS scale in at least 50%). The validation parameters of HPLC method of fluoxetine and cortisol determination indicate the possibility of applying them for determination of both: the level of concentration of the drug in therapeutic drug monitoring and the level of cortisol in serum of patients with endogenous depression.

Simultaneous determination of eight estrogens and their metabolites in serum using liquid chromatography with electrochemical detection.

The liquid chromatography (LC) with electrochemical detection allows to determine, evaluate and validate the level of estrogens and their metabolites in serum. The method is fast and sensitive, and the hormones can be determined simultaneously, from one serum sample. The proposed method was successfully applied to the determination of following estrogens: estrone (E(1)), 17beta-estradiol (E(2)), estriol (E(3)) and following catecholestrogens: 2-hydroxyestradiol (2-OHE(2)), 4-hydroxyestradiol (4-OHE(2)), 4-hydroxyestrone (4-OHE(1)), 2-methoxyestradiol (2-MOE(2)) and 2-methoxyestrone (2-MOE(1)). The method of LC with electrochemical detection (LC/EC) was applied for the determination of catecholestrogens in serum sample taken from pregnant women. Estrogens and catecholestrogens were extracted from 1 mL of serum by applying diethyl ether under the specified conditions. The parameters of the procedure included using a specific mobile phase, applying the column Symmetry C18 (5 microm, 3.0 mm x 150 mm), equipping the applied electrochemical detector with the working glassy-carbon electrode, as well as applying the reference electrode Ag/AgCl. The calibration studies on this study were performed, and a good analytical performance for E(1), E(2), E(3), 2-OHE(2), 4-OHE(2), 4-OHE(1), 2-MOE(2) and 2-MOE(1) was attained, along with low limits of detection (LOD of 0.18-0.30 ng/mL), satisfactory limit of quantification (LOQ of 0.23-0.92 ng/mL) and excellent linear dynamic range (0.6-8.0 ng/mL). In conclusion, the presented methodology is the sensitive method of the simultaneous measurement of eight estrogens and their metabolites from one sample of blood and it might be clinically applied for testing serum of pregnant women, as well as for further studies on estrogens and their metabolites.

Serum cortisol concentration in patients with major depression after treatment with clomipramine.

Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and elevated cortisol (CORT) levels are characteristics of the pathophysiology of major depressive disorder. The aim of this study was to determine whether increased plasma CORT levels appear in patients with major depression and if effective antidepressant treatment by clomipramine (CLO) leads to regulation of CORT level. Plasma CORT levels were measured using high performance liquid chromatography (HPLC) methods in patients with major depression at time zero (before therapy) and after 3 h, 24 h, 4, 6 and 8 weeks of CLO administration. The study included 17 patients (12 women, 5 men; mean age 54.5 years, SD =12.3) and 21 healthy comparison subjects. The patients had a mean score on the 21-item Hamilton Depression Rating Scale (HDRS) of 26.8 (range 22-35). Eight of the patients with major depression recruited for the study showed a 46% increase in CORT concentration compared to the established standard. In 13 patients treated with CLO, serum CLO levels reached a therapeutic range. In recovered depressed patients, antidepressant treatment significantly reduced HDRS scores from the 6th week of treatment. A drop in plasma CORT levels in recovered depressed subjects occurred 0 to 6 weeks after CLO treatment (n = 5, p < 0.046). However, neither subject group exhibited any definitive markers of CORT secretion. In the population studied, patients had distinct profiles of HPA axis dysregulation. Finding a linear correlation between lower CORT secretion and therapeutic plasma CLO levels is the first aim of monitored therapy and may be important for understanding the pathophysiology of major depressive disorder.

Cortisol level in men with major depressive disorder treated with fluoxetine or imipramine.

The aim of this research was to find out whether increased plasma cortisol levels appear in unipolar or bipolar patients with major depressive disorder (MDD) and whether the effective antidepressant treatment by imipramine and fluoxetine leads to regulation of the cortisol level. Cortisol levels were studied in two groups of patients with major depressive disorder: unipolar and bipolar patients treated with fluoxetine (doses: 20-60 mg/day). This group included 5 patients (age 29-46 yr); unipolar and bipolar subjects treated with imipramine (50-150 mg/day), this group included 5 patients (aged 24-70 yr). Cortisol and fluoxetine or imipramine plasma levels were assessed using HPLC methods: before treatment, after 3, 6 and 24 h of drug administration as well as in the 2nd, 4th, 6th, and 8th week of antidepressant treatment. HPLC methods were previously validated. The research conducted and the clinical data may be useful for proving the essential role of enhanced HPA axis activity for the pathogenesis and depressive disorder proceedings.

Development, validation and application of the HPLC method for determination of mianserin in human serum.

A high performance liquid chromatography method for the determination of mianserin in human serum was developed and validated. Doxepin was used as an internal standard. Mianserin was extracted from human serum using a liquid-liquid extraction with hexane:isoamyl alcohol (99:1, v/v). The sample was then dissolved in 0.05 M phosphoric acid (pH=3.0), and after separation on a Hichrom RPB (250 x 4.6 mm, 5 mm) column, the analytes were measured by ultraviolet detection at 214 nm. The recovery ranged from 86.1 to 94.5% for mianserin. The method was specific and linear over the concentration range of 2.0-128.0 ng/mL. The limit of quantification (LOQ) was established at 2.0 ng/mL (CV=13.8%). The accuracy range was from 92.5 to 107.5%. The method was used to measure mianserin in human serum samples obtained from healthy volunteers who had received a single oral dose of 30 mg mianserin. Pharmacokinetic parameters obtained for the mianserin were in agreement with the existing data.

Liquid chromatographic method for the determination of lidocaine and monoethylglycine xylidide in human serum containing various concentrations of bilirubin for the assessment of liver function.

A high-performance liquid chromatographic method is described for determination of lidocaine (2-(dietyloamino)-N-(2,6-dimetylofenylo) acetamid) and its metabolite, monoethylglycine xylidide (MEGX), in human serum containing various concentration of bilirubin. Lidocaine and its metabolite were extracted from human serum using dichloromethane. After separation of the layers and freezing at -32 degrees C, the organic layer was decanted and evaporated under a stream of nitrogen. The sample was dissolved in the mobile phase (12% acetonitrile in 15mM potassium dihydrogen orthophosphate, pH 3.0), and after separation on a Supelcosil LC-8-DB column, the analytes were measured by ultraviolet detection at 205nm. Trimethoprim (TMP) was used as the internal standard. The recovery of the examined analytes ranged from 95.7 to 97.9% for lidocaine and from 98.0 to 99.9% for MEGX. The lower limit of quantification (LLOQ) was established at 200microg/l for lidocaine and at 10microg/l for MEGX. The choice of suitable conditions for chromatographic separation of lidocaine and its metabolite MEGX allowed the elimination of the influence of endogenous bilirubin on the result of analysis.

Prognostic significance of free radicals: mediated injury occurring in the kidney donor.

BACKGROUND: Brain death is associated with hemodynamic disturbances in systemic circulation and metabolic storm, and, thus, free radical-mediated injury to donor tissues was hypothesized. An assessment of oxidative stress in the donor and its effect on posttransplant kidney graft function comprised the scope of the study. METHODS: A prospective study was performed in 27 donors and 50 kidney transplant recipients. Sera from 27 brain-dead organ donors and preservation media were tested for malondialdehyde (MDA) and for total antioxidant status (TAS). Kidneys were preserved in University of Wisconsin-gluconate solution with machine perfusion. Mean ischemia time was 36.7+/-8 hours. Organs were transplanted to recipients on the Polish National Waiting List and posttransplant kidney function was monitored periodically. Posttransplant delayed graft function (DF) was diagnosed when a patient required at least one dialysis within first week after transplantation. Acute rejection was diagnosed clinically and confirmed with fine-needle biopsy if necessary. RESULTS: Thirty-two recipients had immediate graft function (IF), and 18 suffered from DF. MDA level in preservation solution at the end of machine perfusion was significantly higher in the DF group (52.6+/-31 vs. 25.3+/-19 micromol/L) whereas donor TAS activity was lower (1.14+/-0.2 vs. 0.97+/-0.3 mmol/mL). Patients who suffered from acute rejection received kidneys from donors with significantly higher serum MDA (66+/-73 micromol/ml vs. 23+/-49 for patients without rejection). Serum creatinine 12 to 48 months after transplantation correlated to donor- and preservation-solution MDA (P<0.006). CONCLUSIONS: Free-radical mediated injury occurring in the donor and during preservation is strictly correlated with immediate and long-term kidney function. It may also cause grafts to be prone to acute rejection.