Paweł Burchardt

Low-density lipoprotein, its susceptibility to oxidation and the role of lipoprotein-associated phospholipase A2 and carboxyl ester lipase lipases in atherosclerotic plaque formation.

An increased level of low-density lipoprotein (LDL) is a very well established risk factor of coronary artery disease (CAD). Unoxidized LDL is an inert transport vehicle of cholesterol and other lipids in the body and is thought to be atherogenic. Recently it has been appreciated that oxidized products of LDL are responsible for plaque formation properties previously attributed to the intact particle. The goal of this article is to review the recent understanding of the LDL oxidation pathway. The role of oxidized products and key enzymes (lipoprotein-associated phospholipase A2 and carboxyl ester lipase) are also extensively discussed in the context of clinical conditions.

Postinfarction heart failure: surgical and trans-coronary-venous transplantation of autologous myoblasts

Increasing experimental evidence indicates that skeletal myoblasts can be considered as a possible source of cells for regeneration of contractile performance in chronic postinfarction myocardial injury. In experimental models, the observed functional benefit of transplanting skeletal myoblasts into an area of chronic fibrotic myocardial scar has led to the development of clinical trials to evaluate the potential use of autologous skeletal myoblasts for myocardial regeneration in patients with postinfarction heart failure. We conducted an independent, phase I clinical trial to evaluate myoblast transplantation during coronary artery bypass grafting. In addition, to test whether the effect of transplanted cells on myocardial contractility was independent of revascularization, we performed a clinical study of percutaneous transvenous myoblast transplantation—the POZNAN trial. These trials have shown the feasibility of myoblast transplantation during cardiac surgery and via a percutaneous route, as well as the safety of both procedures when performed with concurrent prophylactic administration of amiodarone. Here, we review the details of our observations from both of these phase I clinical trials in the context of the clinical work in cardiovascular cell transplantation performed by others.

The influence of genetic polymorphism of Cyp2c19 isoenzyme on the pharmacokinetics of clopidogrel and its metabolites in patients with cardiovascular diseases

An extensive investigation on pharmacokinetics of clopidogrel and its metabolites as well as pharmacodynamics of the drug was performed in patients with cardiovascular disease carrying various alleles coding CYP2C19 isoenzyme. The influence of non‐genetic factors on the clopidogrel response was also studied. Plasma concentrations of clopidogrel, its carboxylic metabolite, and diastereoisomers of a thiol metabolite (the inactive H3 and the active H4) following an administration of 75 mg of the drug were determined in three groups of patients divided with respect to their CYP2C19 genotype: ultrametabolizers, extensive metabolizers, and intermediate metabolizers. The mean peak plasma concentration of H4 in intermediate metabolizers was 3.1‐ and 2.8‐fold lower than that of ultrametabolizers (P = 0.055) and extensive metabolizers (P = 0.026), respectively. The mean H4 area under the curve (AUC0–24 h) for intermediate metabolizers were significantly lower than that for ultrametabolizers (P = 0.046). Intermediate metabolizers exhibited a significantly higher platelet aggregation than ultrametabolizers and extensive metabolizers (P = 0.035). A multivariate analysis showed that the effect of CYP2C19*2 allele on an ADP‐induced platelet aggregation was better pronounced in the presence of non‐genetic risk factors (P = 0.008).

Impact of common ABCB1 polymorphism on pharmacokinetics and pharmacodynamics of clopidogrel and its metabolites

The reasons of clopidogrel (CLP) resistance are still unclear. The response to CLP may be influenced by both genetic and non‐genetic factors. Among genetic factors, common polymorphisms in the gene coding glycoprotein‐P (P‐gp, MDR1 and ABCB1) are considered as potential determinants of the efficacy of CLP treatment. The aim of this study was to evaluate the influence of ABCB1 3435C>T genetic polymorphism on the pharmacokinetics and pharmacodynamics of CLP and its metabolites: diastereoisomers of thiol metabolite (the inactive H3 and the active H4) and inactive carboxylic derivative.

The Effect of Atorvastatin Treatment on Lipid Profile and Adhesion Molecule Levels in Hypercholesterolemic Patients: Relation to Low-Density Lipoprotein Receptor Gene Polymorphism

Inflammation has been indicated to play a major role in the development of atherosclerosis. The beneficial effect of statins has been suggested to be related to their anti-inflammatory properties. We have studied plasma levels of soluble adhesion molecules in patients with hypercholesterolemia before and after 3 months of treatment with atorvastatin and evaluated possible relations to the mutations in low-density lipoprotein receptor (LDLR) gene. In patients with no LDLR gene polymorphism (group A), lower baseline levels of total cholesterol and LDL cholesterol were found than in patients with LDLR gene polymorphism (group B). The soluble adhesion molecules sICAM-1, sE-selectin and sP-selectin, but not sVCAM-1 and sL-selectin, were higher in group B than in group A. sICAM-1 levels decreased in group A by 7% (p = 0.007) and in group B by 21% (p = 0.039), whereas levels of sVCAM-1 decreased in group A by 12% (p = 0.001) and in group B patients by 19% (p = 0.039). Atorvastatin did not change sE-selectin nor sP-selectin levels in group A. However, in group B, the treatment reduced E-selectin and sP-selectin levels by 39% (p = 0.007) and 24% (p = 0.007), respectively. Atorvastatin attenuates the inflammatory reaction in hypercholesterolemic patients, but in patients with LDLR gene polymorphism, this effect is more profound.

Presence of irregularity in region between −1115 and −784 nt in P1 promoter of Insulin-Like Growth Factor-1 gene may indicate beneficial effect on coronary arteries in a group of patients with stable angina: preliminary data

Insulin-like growth factor-1 (IGF-1) plays an important role in arterial homeostasis. Its properties seem to depend on circulating IGF-1 level changes. The various IGF-1 levels are caused by varied expression of IGF-1 gene, due to the polymorphic structure of IGF-1 gene or its regulatory sequences. We examined the P1 promoter, being responsible for most IGF-1 transcripts, in patients with stable angina, to evaluate its sequence changes and to assess its influence on protein synthesis as well as on the degree of arteriosclerosis. For that purpose we evaluated the DNA isolated from blood cells. The DNA was amplified by using polymerase chain reaction (PCR), then analyzed using the SSCP (single-strand conformation polymorphism) technique. Products of every stage were verified by electrophoresis on agarose gel. In addition, every patient had coronary angiography performed and IGF-1, IGFBP3, and lipid levels measured. The SSCP in the region between −1115 and −784 nt was less commonly observed among subjects with positive MI (myocardial infarction) familial history (P = 0.0008) and with MI history (P = 0.012) than in patients without these conditions. Subjects with this irregularity tended towards higher circulating IGF-1 levels. In addition high Gensini scores — over 95th percentile, 105 points in our study — were more frequent in SSCP patients (P = 0.03). We presume that presence of SSCP in the P1 region between −1115 and −784 nt may positively affect coronary arteries by increasing circulating IGF-1 levels, but its clinical importance requires molecular verification and further studies.

The Role of Hematological Indices in Patients with Acute Coronary Syndrome

An increased systemic and local inflammation plays a key role in the pathophysiology of acute coronary syndrome (ACS). This review will discuss the role of hematological indices: white blood cells (WBC), neutrophil to lymphocyte ratio (NLR), red cell distribution width (RDW), and platelet indices, that is, platelet to lymphocyte ratio (PLR), mean platelet volume (MPV), and platelet distribution width (PDW) in the case of ACS. In recent years, a strong interest has been drawn to these indices, given that they may provide independent information on pathophysiology, risk stratification, and optimal management. Their low-cost and consequent wide and easy availability in daily clinical practice have made them very popular in the laboratory testing. Furthermore, many studies have pointed at their effective prognostic value in all-cause mortality, major cardiovascular events, stent thrombosis, arrhythmias, and myocardial perfusion disorders in terms of acute myocardial infarction and unstable angina. The most recent research also emphasizes their significant value in the combined analysis with other markers, such as troponin, or with GRACE, SYNTAX, and TIMI scores, which improve risk stratification and diagnosis in ACS patients.

The pharmacokinetics of the effervescent vs. conventional tramadol/paracetamol fixed-dose combination tablet in patients after total gastric resection

BACKGROUND Tramadol/paracetamol is a fixed-dose combination prescribed for the relief of moderate to severe pain. The combination acts synergistically and guarantees the rapid onset of paracetamol and the prolonged analgesic effect of tramadol with good tolerability. These drugs are often used in various formulations in the treatment of patients with postoperative pain, e.g. after stomach resection. Gastrectomy leads to pathophysiological changes within the alimentary tract, which may affect the process of drug absorption. The aim of the research was an analysis of the pharmacokinetics of tramadol/paracetamol from effervescent and conventional tablets in patients after total gastrectomy. METHODS The research was carried out on patients after gastrectomy with Roux-en-Y reconstruction. The patients received two tramadol/paracetamol fixed-dose combination tablets in a single orally administered dose of 75/650 mg (2 × 37.5/325 mg). The patients were subjected to one of the two study drug group with: I. effervescent tablet (ET) (n = 14; mean [SD] age, 63.4 [10.1] years; weight, 75.5 [15.3]kg; and BMI, 26.0 [4.6]kg/m(2)) and II. conventional tablet (CT) (n = 12; mean [SD] age, 66.8 [7.7] years; weight, 79.8 [17.8]kg; and BMI, 27.4 [5.3]kg/m(2)). Blood samples were collected within 10 h after the drug administration. The plasma concentrations of tramadol and paracetamol were measured with validated HPLC (high-performance liquid chromatography) method with UV detection. RESULTS The comparison of the paracetamol and tramadol C(max) ratio for the ET group with that of the CT group gave ratios of 1.16 [90% confidence interval (CI) 1.06, 1.27] and 0.86 (90% CI 0.72, 1.02), respectively. The comparison of the paracetamol and tramadol AUC(0-t) ratio for the ET group with that of the CT group showed ratios of 0.99 (90% CI 0.88, 1.10) and 1.00 (90% CI 0.82, 1.22), respectively. The comparison of the difference for the effervescent and conventional formulation gave an estimated decrease in t(max) of 0.5 h for paracetamol and 0.13 h for tramadol. CONCLUSIONS In view of the changes in the pharmacokinetics of paracetamol and tramadol in the patients after gastric resection for both formulations compared the conventional tablet seems to be more appropriate due to the comparable rate of absorption of both substances, higher concentrations of tramadol and comparable exposure to paracetamol.

The presence of thin glomerular basement membranes in various glomerulopathies

ABSTRACT Results of 61 cases of various glomerulopathies with thin glomerular basement membranes are presented. The largest group of 31 cases consisted of mesangial glomerulonephritis. The second largest group consisted of 19 patients with small glomerular lesions described as non-specific. This group stood out in both clinical presentations and in the higher diversity of lesions within the lamina densa of the basement membrane. The results of measurements of the lamina densa in various glomerulopathies were compared to those obtained in control groups consisting of thin basement membrane syndrome and submicroscopic glomerulonephritis.

All dangerous types of endoleaks after endovascular aneurysm repair in a single patient.

Endovascular aneurysm repair (EVAR) has become tremendously popular in recent years. However, the long-term results of these stent grafts are uncertain and are still being evaluated. According to some data, the graft-related complication rate after EVAR could be as high as 43% in long-term observation. In this case report, we present a patient who had all dangerous types of endoleaks after EVAR and required sophisticated management including endovascular and open surgical repairs. After repeated invasive treatment, it was possible to exclude all endoleaks, and now the patient is free from graft-related complications. Although EVAR has become very popular, we should remember about possible complications, which could be very severe and life-threatening. For this reason, the choice between endovascular and open repair of abdominal aortic aneurysm should be well considered.