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Biomedical subjects

K Orzechowska-Juzwenko

Publications and source records attributed to K Orzechowska-Juzwenko.

At least 19 recordsLinked to original sources
PubMed2004

Monitoring methotrexate therapy in patients with rheumatoid arthritis.

OBJECTIVE: The aim of this work was to study methotrexate (MTX) kinetics and their relation to the effectiveness of the therapy in patients with rheumatoid arthritis (RA). Other aims were to analyze the influence of MTX on liver, kidney, hematopoietic function and to determine the possibility of using early drug concentrations to predict the subsequent value of the treatment. MATERIAL AND METHODS: The observations were carried out in 49 patients with RA after the first dose of MTX and after 7 months of treatment. Methotrexate concentrations in blood serum and urine were determined using fluorescence polarization immunoassay applying a TDx Abbott analyzer. RESULTS: No correlation between concentrations, pharmacokinetic parameters and the duration of the disease, its activity, clinical symptoms, observations pertaining to the disease made by physician and patients and morning stiffness of joints was seen. Of those tests for the evaluation of liver, kidney and hematopoietic function, only the mean activity of N-acetyl-beta-D-glucosaminidase (NAG) in urine was significantly elevated both before and after treatment with MTX when compared to corresponding values in the control group of healthy subjects. We have formulated equations allowing for the early recognition of patients with a risk of adverse effects due to impaired elimination of MTX from the body. CONCLUSION: Our results show that monitoring MTX therapy using concentrations in patients with RA does not significantly improve the effectiveness of the treatment, but it can play an important role in increasing the safety of this drug.

Antirheumatic Agents↗
PubMed2003

The influence of locally implanted high doses of gentamicin on hearing and renal function of newborns treated for acute hematogenous osteomyelitis.

BACKGROUND: [corrected] Osteomyelitis and arthritis still present a serious diagnostic and therapeutic problem. Difficulties arise in particular in the treatment of acute hematogenic osteomyelitis (AHO) in newborns where mega-doses of gentamicin are administered locally for about 3 weeks. Gentamicin possesses strong oto- and nephrotoxicity and the occurrence of these adverse effects depends on the duration of treatment and the serum drug concentration. OBJECTIVE: Aim of the study was to evaluate the influence of local gentamicin application on auditory and kidney functions. MATERIAL AND METHODS: Twenty newborns (14 boys and 6 girls) with AHO were treated at the Department of Pediatric Surgery, Marciniak Hospital, Wroclaw, Poland, by local implantation of miniseptopal or gentamicin sponge. Serum urea, creatinine, antibiotic concentrations and NAG activity/g creatinine ratio in urine were estimated before and 1, 4, 8, 16 days after the operation and compared to values in the control group. Brainstem-evoked auditory potentials (BAEP) were examined before, during the first 3 weeks, and 6-11 months after gentamicin implantation. RESULTS: Mean gentamicin serum concentrations were: 0.67 +/- 0.98 mg/l on the 1st day, 0.16 +/- 0.37 mg/l on the 4th day, 0.03 +/- 0.09 mg/l on the 8th day, 0.01 +/- 0.03 mg/l on the 16th day after operation and did not exceed the upper limit of the therapeutic range. N-acetyl-beta-D-glucosaminidase (NAG)/g creatinine in urine ratios were satisfactory: 77.91 +/- 36.22 UI/g before the operation, 146.51 +/- 82.27 UI/g on the 4th, 162 +/- 111 UI/g on the 8th, 168 +/- 59.83 UI/g on the 16th day after operation and were statistically significantly (p < 0.05) higher than values in the control group. Serum urea and creatinine levels were in the normal range in all groups. Initial BAEP were well in the normal range in 15 of 16 children before treatment and in 14 of 16 children after treatment. CONCLUSIONS: Locally applied gentamicin as miniseptopal or sponge in newborns produces gentamicin concentrations close to the minimal therapeutic serum concentration which are present over a prolonged period. The raised NAG values in urine and normal serum urea and creatinine levels during treatment with gentamicin without concomitant clinical symptoms of renal failure suggest subclinical destruction of the renal tubules. Lack of change in BAEPs shows that there is no impairment of auditory function.

Acetylglucosaminidase↗
PubMed2002

CYP2D6 extensive, intermediate, and poor phenotypes and genotypes in a Polish population.

OBJECTIVE: This study investigated the distribution of the CYP2D6 genotypes and phenotypes in a Polish population and compared the concordance of the two methods. METHODS: Six hundred unrelated healthy individuals from southwestern Poland were studied. The CYP2D6 phenotype was analyzed in 300 individuals using sparteine as a model drug. The CYP2D6 genotype was analyzed in 300 individuals by polymerase chain reaction amplification and restriction fragment length polymorphism techniques for the CYP2D6*1, CYP2D6*3, and CYP2D6*4 alleles. Additionally, in 60 randomly selected healthy individuals both the CYP2D6 phenotype and genotype was assessed to determine accordance between the methods. RESULTS: Of 300 participants in the study 25 (8.3%) were classified as poor metabolizers, 44 (14.7%) as intermediate metabolizers, and 231 (77%) as extensive metabolizers of sparteine. The frequency of CYP2D6*1, CYP2D6*3, and CYP2D6*4 alleles among the genotyped 300 persons was 75.7%, 1.3%, and 23.0%, respectively. The frequency of CYP2D6 deficient genotypes in a Polish population (8.0%) was similar to phenotyping results. The comparison of phenotype and genotype in 60 randomly selected individuals showed a good concordance of the obtained results. CONCLUSIONS. The frequencies of poor metabolizers for CYP2D6 phenotype (8.3%) and genotype (8.0%) in a Polish population from the southwestern region are in concordance and compare well with most results of poor oxidation metabolizers in other white populations.

Adolescent↗
PubMed2001

The influence of CYP2D6 polymorphism on the antiarrhythmic efficacy of propafenone in patients with paroxysmal atrial fibrillation during 3 months propafenone prophylactic treatment.

OBJECTIVE: Propafenone (PPF) is an antiarrhythmic, Class Ic agent. Its metabolism is genetically controlled by a cytochrome P450 isoenzyme named CYP2D6, which shows polymorphism in human population. The aim of this paper was to determine the correlation between the antiarrhythmic efficacy of PPF and the oxidation phenotype. SUBJECTS AND MATERIAL: The study group consisted of 42 patients, aged 36 to 75 years, suffering from paroxysmal atrial fibrillation (AF). The oxidation phenotype was described by the metabolic ratio (MR) of sparteine. The MR value separated the group of poor metabolizers (MR > 20) from the group of extensive metabolizers (MR < 20) with the subgroup of very extensive metabolizers (MR < 1). METHOD: The study was conducted during a 3-month PPF therapy for the prophylaxis of paroxysmal atrial fibrillation. PPF was given orally, 300-450 mg/day. The oxidation phenotype was checked prior to the administration of PPF. Serum concentration of PPF at 7, 11 days and the end of PPF therapy were determined. Statistical analysis of data was performed with the chi2 test and the Pearson's correlation methods. RESULTS: In the group of 42 patients, PPF therapy was 100% effective in poor metabolizers (PM). In extensive metabolizers (EM), 61% efficacy was observed with efficacy 0% in very extensive metabolizers (VEM). The correlation between oxidation phenotype and the ability to maintain sinus rhythm (SR) was statistically significant (r = 0.414, p < 0.05). CONCLUSIONS: The antiarrhythmic efficacy of propafenone depends on the oxidation phenotype; 100% efficacy occurred in the group of poor metabolizers whereas PPF, at the dose tested, was ineffective in very extensive metabolizers.

Administration, Oral↗
PubMed2001

Metabolic functions of the liver during chemotherapy in children with acute lymphoblastic leukemia.

OBJECTIVE: The purpose of the present work was estimation of liver function using the phenazone test and commonly used biochemical tests in children with acute lymphoblastic leukemia (ALL) during anticancer treatment. METHODS: Observations were carried out in the same 21 patients with ALL before the beginning of chemotherapy, after Protocol I and after Protocol M of the antileukemic treatment carried out according to the program BFM 86. RESULTS: The applied chemotherapy inhibited phenazone elimination. Both phenazone half-life and metabolic clearance rate were significantly different in patients after treatment with anticancer drugs, especially with high-dose of methotrexate (MTX), from those in patients before the beginning of chemotherapy (p < 0.001). Moreover, after MTX administration transaminases activity and serum bilirubin concentration were significantly higher than before treatment (p < 0.05). CONCLUSION: Our results showed that in children with acute lymphoblastic leukemia, anticancer chemotherapy decreased liver metabolic capacity. Particularly, high-dose methotrexate treatment altered the elimination of phenazone by inhibiting the activity of hepatic mixed function oxidase system. This change may lead to an increase in toxicity of active drugs which are metabolized by this enzyme system. In addition, altered activity of liver metabolic function can impair transformation of prodrugs to active forms. It should be considered in selection of individual drug dosages. The objective estimation of the type and degree of liver dysfunction can only be achieved by the combination of a quantitative phenazone dynamic test and static biochemical tests.

Analysis of Variance↗
PubMed2001

[Monitoring of renal function in epileptic children and teenagers treated with valproic acid or carbamazepine in concomitant therapy with tiagabine].

The aim of the study was the evaluation of the influence of 4-month concomitant tiagabine (TGB) and valproic acid (VPA) or carbamazepine (CBZ) therapy on renal function of epileptic children and teenagers. Initial parameter values, indicated on renal disfunction, were compared with these obtained after VPA and TGB or CBZ and TGB therapy and with values in healthy children and teenagers. Investigation group was composed of 22 children and teenagers with drug-resistant focal epilepsy. We observed that in the time of concomitant VPA and TGB therapy increased the NAG/g creatinine activity index. In spite the fact of statistical significance of these changes, they were not outside the normal range. beta 2-microglobulin concentrations in urine of epileptic children treated with VPA in monotherapy before concomitant therapy with TGB were higher than in control group. That difference was statistically significant. Addition of TGB to the therapy normalized this parameter. During concomitant VPA and TGB or CBZ and TGB therapy we didn't observe statistically significant changes of parameters indicating on glomerular disfunction. In the VPA therapy before concomitant treatment with tiagabine the disfunction of tubules and glomerules was observed. On the other side in the concomitant VPA and TGB therapy the disfunction of tubules and glomerules didn't occurred. We can conclude that concomitant therapy VPA or CBZ with tiagabine don't affect the renal function in clinical significant manner. Therapy with VPA could leads to minimal disfunction of tubules what is represented by increasing of beta 2-microglobulin level in urine.

Acetylglucosaminidase↗
PubMed2000

[Drug interactions].

Adverse drug interaction it is therapeutically unwanted effect, which may appear during simultaneous treatment with two or more drugs and as a consequence may reduce or increase their pharmacologic action; may lead to the toxic effects and even to the appearance of qualitatively different from the expected one pharmacologic action. In this article are presented criteria determining the clinical significance, risk factors, kinds and consequences of adverse drug interactions. The drugs which can be the most dangerous in the context of adverse interactions, when are used simultaneously with other medications are: anaesthetics, anticoagulants, antidiabetics, nonsteroidal antiinflammatory drugs, drugs used in cardiac and circulatory system diseases, hypolipaemic drugs, theophylline, antibiotics, psychotropics, antiepileptics, antineoplastics, cyclosporine, tacrolimus.

Drug Interactions↗
PubMed2000

[Adverse reactions of coumarin derivative interactions].

Many drugs interact with warfarin and other oral anticoagulants. Some of them reduce the activity of the anticoagulants and intensify of thrombosis symptoms. Others increase the activity and can cause bleeding if the dosage of the anticoagulant is not reduced appropriately. Both situations are clinically serious and may be fatal. Details of these interactions are given in this article.

Anticoagulants↗
PubMed2000

[Interactions of nonsteroidal anti-inflammatory drugs].

The nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used and very commonly prescribed, especially in the elderly population. Many of NSAIDs are over-the-counter (OTC) drugs, which increase risk of interactions with other drugs. Types of interactions, their clinical relevance, groups of patients with increased risk of interactions and prevention methods are shortly described.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

[Unwanted drug interaction between anti-arrhythmic drugs and drugs used for heart failure].

The appearance of adverse drug reactions may depend on the category of used drugs as well as on the coexistence of a pathological stage. Clinically important are: interactions of digitalis glycoside drugs leading to the occurrence or intensification of toxic symptoms characteristic for those drugs; interactions of antiarrhythmic drugs which may cause proarrhythmic effects and hypotension, and also interactions of nitrates resulting in lowering of the blood pressure. Quinidine, verapamil, nitrendipine, amiodaron, propafenone, captopril, spironolactone decrease renal clearance of digoxin, and amilorid/triamteren lower the extrarenal clearance of this drug. Thus the outcome of those concommitant therapies is the increase of digoxin serum concentration and appearance of toxic symptoms. Clinically dangerous, in the course of the antiarrhythmic therapy, is the increased risk of the arrhythmia appearance when two or more antiarrhythmic drugs are applied concomitantly. Antiarrhythmic drugs class IA (quinidine, disopyramide), class III (sotalol, amiodarone), class IV (calcium channel blockers) used at the same time with potassium depleters diuretics or beta-blocking agents result in the inhibition of repolarization and the increased duration of activation potential with the risk of developing arrhythmia of the torsade de pointes types. Nitrates interactions are mainly of the pharmacodynamic character. Most common adverse drug reaction, observed during the concomitant nitrates and another circulatory drug therapy, is excessive lowering of the blood pressure. These may lead to the decrease in the therapeutic efficacy of these combinations. Interactions of circulatory drugs are numerous, sometimes difficult to predict and they may lead to the intensification of the adverse drug reaction and lowering of their therapeutic efficacy.

Anti-Arrhythmia Agents↗
PubMed2000

[Interactions between drugs and results of laboratory tests].

The aim of the paper was the presentation of the newest results of studies on the effects of drugs on clinical laboratory tests. It was especially emphasized an important and clinical significance of these effects of drugs on laboratory tests.

Clinical Laboratory Techniques↗
PubMed1999

Phenazone as a marker of liver-metabolic function in patients with acute leukemia.

OBJECTIVE: The aim of this work was to study the influence of neoplastic disease, especially acute myeloblastic leukemia (AML), and its chemotherapy on the activity of hepatic microsomal enzymes by using phenazone, as a marker of oxidative drug metabolizing activity. METHODS: The observations were carried out in 21 patients with AML and in 53 healthy volunteers. The influence of disease on phenazone kinetics was studied before chemotherapy and the effect of anticancer drugs administration after the first cycle of chemotherapy. RESULTS: The mean phenazone half-life time was significantly shorter in patients with AML (8.79 (3.01) h) than in control group (11.08 (3.61) h) (p < 0.012). Treatment with anticancer drugs, especially with epirubicine, inhibited phenazone elimination. The mean phenazone half-life time was significantly longer (18.08 (8.80) h) and the mean metabolic clearance rate was significantly smaller (33.92 (15.40) ml/min) after chemotherapy in comparison with the initial value, before treatment (10.22 (2.90) h), (p < 0.01) (50.33 (20.29) ml/min) (p < 0.008). CONCLUSION: Our results lead to the conclusion that phenazone is an important index of hepatic metabolic capacity in patients with acute myeloblastic leukemia. The evaluation of its kinetics allowed to early recognition of the presence and the degree of drug oxidizing modification. Acceleration of phenazone elimination before treatment and its inhibition after chemotherapy, particulary epirubicine, may suggest that in patients with AML elimination of the other drugs metabolized by the pathway similar to phenazone also may be changed. It should be considered in individualization of their dosage regimen.

Adult↗
PubMed1999

[Oxidation phenotype as a risk factor for development of allergic diseases].

The relationship between genetically determined polymorphic metabolism and susceptibility to allergic diseases has aroused much interest. The aim of our study was to evaluate whether patients with allergic diseases, like atopic asthma and allergic rhinitis differ from healthy persons in their ability to oxidize sparteine as a model drug. The study was completed by 200 persons, 40 patients with allergic diseases--20 with atopic asthma and 20 with allergic rhinitis and 160 healthy volunteers as a control group. The results of our study revealed a predominance of very extensive metabolizers of sparteine among patients with allergic diseases in comparison with healthy volunteers. The difference in the oxidation metabolic ratio (MR) frequency distribution between patients with allergic diseases and healthy persons was statistically significant. Relative risk (odds ratio) of development of atopic asthma was 3.29 times higher, and that of allergic rhinitis 2.94 times higher for persons with very extensive oxidation phenotype. Our results represent some evidence for a possible relationship between extensive, rapid oxidation phenotype and the higher susceptibility to development of atopic asthma and allergic rhinitis.

Adolescent↗
PubMed1997

[Biotransformation of phenazone and sulfadimidine as markers of liver metabolism of drug and xenobiotic oxidation and acetylation in women with breast cancer].

The aim of our study was to determine phenazone pharmacokinetics as an index of hepatic microsomal enzymes activity and acetylation phenotype in women with breast cancer. Phenazone test was made in 41 women with breast cancer and in 25 healthy women as a control group. Acetylation phenotype was measured in 40 women with breast cancer and in 25 healthy women as a control group. The plasma concentration of phenazone was estimated by the spectrophotometric method of Brodie and associates. Acetylation phenotype was determined by the Bratton-Marshall method in Varley's modification. The mean phenazone half-life time (t0,5), shortened significantly and the mean elimination rate constant (K) increased in women compared with a group of healthy persons. Mean clearance rate was increased in women with breast cancer too, compared with a group of healthy women. Acceleration of phenazone elimination may suggest that in patients with breast cancer elimination of the other drugs metabolized by the pathway similar to phenazone also may be changed. This should be considered in selection of their dosage. We have observed the predominance of rapid acetylators in women with breast cancer comparing with healthy persons. This difference was not statistically significant. Our results of acetylation phenotype in women with breast cancer suggests that rapid acetylation may be a factor of susceptibility to breast cancer.

Acetylation↗