We used a rat model to assess the role of nephrin, podocin, and desmin in the pathogenesis of IgA nephropathy (IgAN). A rat IgAN model was established by administration of BSA, CCl4, and lipopolysaccharide (LPS) and compared with healthy control rats. Urinary protein, urine red blood cells, and biochemical parameters were measured for 12 weeks. Renal morphology and ultrastructure were examined by light and electron microscopy. Immunofluorescence was used to assess IgA deposition in the glomeruli and to measure expression of nephrin, podocin, and desmin. Real-time quantitative PCR was used to measure expression of nephrin, podocin, and desmin mRNAs. IgAN rats developed proteinuria at week-6 and this worsened over time. Pathological changes were evident under light microscopy at week-8 and under electron microscopy at week-4. Immunofluorescence analysis showed deposition of IgA in the kidneys of IgAN rats, but not control rats. IgAN rats had increased expression of glomerular podocin, nephrin, and desmin mRNAs and proteins at week-4. The expression of nephrin, podocin and desmin proteins and the expression of podocin and desmin mRNAs preceded the increase in urinary protein. Taken together, our study of a rat model of IgAN indicates that changes in the expression and distribution of nephrin, podocin, and desmin precede and may cause foot process fusion and proteinuria., H.-Y. Lu, ... [et al.]., and Obsahuje seznam literatury
The first trimester of pregnancy is characterized by continuous proliferation, invasion and differentiation of cytotrophoblasts. These processes are precisely controlled both, in space and time by molecules such as endothelin-1 (ET-1). ET-1 is expressed in human first trimester trophoblast and is known to stimulate cytotrophoblast proliferation through endothelin A and B receptor subtypes (ETA and ETB), and cytotrophoblast invasion through ETB. However, temporal changes of the ET system during the first trimester of pregnancy have not been previously studied. This study tested the hypothesis that ET-1 release, ETA and ETB expression are increased towards the end of the first trimester of pregnancy (weeks 10-12 vs. weeks 6-9), resulting in increased cytotrophoblast proliferation and invasion. Tissue samples were obtained from 17 surgical pregnancy interruptions (week 6-9: n=9; week 10-12: n=8). After cytotrophoblast isolation, the invasive and proliferative phenotypes were immune-separated by an α6-integrin antibody. Both proliferative and invasive cytotrophoblasts were cultured separately on plastic or Matrigel for 24 h. ET-1 release into the culture medium of both cytotrophoblast subtypes was measured by radioimmunoassay. ETA and ETB mRNA expression was measured by RT-PCR, and the ET-1 effect on cytotrophoblast proliferation and invasion was determined using proliferation and invasion assays, respectively. ET-1 release increased from early to late first trimester of pregnancy in both proliferative (1.8-4.5 fold) and invasive cytotrophoblasts (9.3-28 fold), especially when cultured on Matrigel. This was paralleled by less ETB mRNA on invasive cytotrophoblasts independent of the time period in first trimester, whereas ETA expression was similar on proliferative an invasive cytotrophoblasts. Proliferation and invasion of cytotrophoblasts under control conditions decreased from early to late first trimester. The ET-1/ET-receptor system changes between weeks 6-9 and 10-12 in pregnancy. Our data suggest an autocrine and endocrine ET-1 effect, which is stronger in late than in early first trimester of pregnancy paralleled by different stimulatory effects on trophoblast invasion and proliferation. In general, this suggests time as an additional effector of the critical processes governing placental development in the first trimester of human pregnancy., A. Majali-Martinez, S. Barth, U. Lang, G. Desoye, M. Cervar-Zivkovic., and Seznam literatury
The role of the glycocalyx of arterial resistance vessels in regulating blood flow in vivo is not fully understood. Therefore, the effect of glycocalyx damage using two separate compounds, hyaluronidase and N-Formylmethionyl-leucyl-phenylalanine (fMLP), was evaluated in the iliac artery vascular bed of the anaesthetised pig. Blood flow and pressure were measured in the iliac, an adjustable snare was applied to the iliac above the pressure and flow measurement site to induce step decreases (3 occlusions at 3-4 min intervals were performed for each infusion) in blood flow, and hence iliac pressure, and vascular conductance (flow/pressure) was calculated. Saline, hyaluronidase (14 and 28 μg/ml/min), and fMLP (1 μM/min) were infused separately, downstream of the adjustable snare and their effect on arterial conductance assessed. Hyaluronidase at the higher infusion rate and fMLP both caused a reduction in arterial conductance, and hence an increase in blood flow resistance. In conclusion, the results show that glycocalyx damage causes an increase in resistance to blood flow in the iliac artery vascular bed., T. Ruane-O’Hora, F. Markos., and Seznam literatury
An oxidant/antioxidant imbalance is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). We hypothesized that antioxidant capacity reflected by erythrocyte glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) activities, and serum levels of the lipid peroxidation product malondialdehyde (MDA), may be related to the severity of obstructive lung impairment in patients with COPD. Erythrocyte GPx, SOD and CAT activities, and serum levels of MDA were measured in 79 consecutive patients with stable COPD. Pulmonary functional tests were assessed by bodyplethysmography. Moderate COPD (FEV1 50-80 %) was present in 23, and severe COPD (FEV1 < 50 %) in 56 patients. Erythrocyte GPx activity was significantly lower, and serum MDA levels were significantly higher in patients with severe COPD compared to patients with moderate COPD (GPx: 43.1±1.5 vs. 47.7±2.9 U/gHb, p<0.05, MDA: 2.4±0.1 vs. 2.1±0.1 nmol/ml, p<0.05). Linear regression analysis revealed a significant direct relationship between FEV1 and erythrocyte GPx activity (r = 0.234, p<0.05), and a significant inverse relationship between FEV1 and serum MDA levels (r = -0.239, p<0.05). However, no differences were observed in the erythrocyte SOD and CAT activities between the two groups of patients with different severity of COPD. Findings of the present study suggest that antioxidant capacity reflected by erythrocyte GPx activity and serum levels of the lipid peroxidation product MDA are linked to the severity of COPD., Z. Kluchová, D. Petrášová, P. Joppa, Z. Dorková, R. Tkáčová., and Obsahuje bibliografii a bibliografické odkazy
In order to assess whether intratesticular hormone content may be helpful for prediction of successful conception in men with fertility problems, five sex steroids, testosterone, dihydrotestosterone, androstenedione, estradiol and, for the first time epitestosterone, were measured in testicular tissue obtained by surgical retrieval from total 84 men. The group consisted of non-obstructive azoospermic men, aged 21-67 years who attended the centre for in vitro fertilization. Steroids after ether extraction and solvent partition were separated by high performance liquid chromatography and then measured by specific radioimmunoassays. The values varied considerably with means ± S.D. 2.43±2.47, 0.27±0.24, 0.080±0.13, 0.071± 0.089 and 0.31±0.27 for testosterone, dihydrotestosterone, androstenedione, estradiol and epitestosterone, respectively., L. Zamrazilová ... [et al.]., and Obsahuje seznam literatury
Primary aldosteronism (PA) is associated with objectively measured lower physical fitness and blunted response of the renin-angiotensin-aldosterone system to exercise. The purpose of this pilot study was to objectively measure exercise response of the renin-angiotensin-aldosterone system and cardiopulmonary fitness changes after laparoscopic adrenalectomy (ADE) in patients with unilateral PA. We examined a total of 14 patients with confirmed PA before and after ADE, by means of spiroergometry and hormonal evaluation. As expected, after adrenalectomy basal aldosterone (Aldo) levels before exercise decreased significantly, with a concomitant increase in plasma renin (PR). The increase in Aldo (285.9±171.3 to 434.1± 278.2 ng/l; p=0.02) and blunted increase in PR (7.1±0.4 to 8.9±10.4 pg/ml; NS) post-exercise before ADE became significant after ADE Aldo post-ADE (46.8±18.8 to 106.5± 68.1 ng/l; p<0.0001) and PR post-ADE (20.1±14.5 to 33.9± 30.7 pg/ml; p=0.014). After adrenalectomy, the patients had a non-significant increase in peak workload and VO2peak. We found normalization of the renin-angiotensin-aldosterone system response to exercise with little changes in cardiopulmonary fitness six months after ADE., V. Tuka, M. Matoulek, J. Rosa, O. Petrák, O. Mikeš, Z. Krátká, B. Štrauch, R. Holaj, T. Zelinka, J. Widimský., and Seznam literatury
Attention has recently been focused on endothelial function after a single high-fat meal, i.e. on the anticipated direct atherogenic effect of triglyceride-rich lipoproteins. Our study was designed to investigate the effect of a low-fat diet given for four weeks followed by a high-fat diet for another four weeks. At the end of each dietary period, a non-invasive ultrasound investigation of endothelial function of the brachial artery was performed along with laboratory tests. Endothelial function was measured immediately before the dietary load and after three and six hours in 11 healthy volunteers. The results were expressed as percentage of the changes in artery diameter at rest and during hyperemia; the data were processed using computer technology. When compared to the low-fat regimen, the total cholesterol content rose after the high-fat diet from 4.28 mmol/l to 5.15 mmol/l (p<0.05) in the whole group of volunteers. There was no difference between both dietary regimens in baseline triglycerides. The brachial artery dilatation under basal conditions was 5.26±2.88 mm after the high-fat diet compared with the value of 3.13±3.01 mm (p<0.05) after the low-fat diet. When measured individually endothelial function in the whole group of volunteers in the course of the day, the degree of arterial dilatation after one month on low-fat diet was 3.13±3.0 %, 3.88±2.5 % and 5.23±3.3 % at single measurement. When comparing arterial dilatation at two closest measurements, a non-significant trend, p>0.05 was seen in either case. The following values were obtained after one month on the high-fat diet: 5.26±2.9 %, 4.47±1.7 %, and 6.2±3.6 %; again showing a non-significant trend of p>0.05. In this study, a single high-fat meal at the different dietary regimen did not significantly influence the vasoreactivity of the brachial artery in young volunteers., T. Šejda, J. Kovář, J. Piťha, R. Cífková, E. Švandová, R. Poledne., and Obsahuje bibliografii
Cardiac repolarization is prolonged in diabetes mellitus (DM), however the distribution of repolarization durations in diabetic hearts is unknown. We estimated the ventricular repolarization pattern and its relation to the ECG phenomena in diabetic mice. Potential mapping was performed on the anterior ventricular surface in healthy (n=18) and alloxan-induced diabetic (n=12) mice with the 64-electrode array. Activation times, end of repolarization times, and activation-recovery intervals (ARIs) were recorded along with limb lead ECGs. ARIs were shorter in the left as compared to right ventricular leads (P<0.05). The global dispersion of repolarization, interventricular and apicobasal repolarization gradients were greater in DM than in healthy animals (P<0.03). The increased dispersion of repolarization and apicobasal repolarization gradient in DM correlated with the prolonged QTc and Tpeak-Tend intervals, respectively. The increased ventricular repolarization heterogeneity corresponded to the electrocardiographic markers was demonstrated in DM., M. A. Vaykshnorayte, A. O. Ovechkin, J. E. Azarov., and Obsahuje seznam literatury
Cytomegalovirus (CMV) infection influences both short and long term outcomes in immunosuppressed organ transplant recipients. The aim of this study was to evaluate the effect of different induction immunosuppression regimens on CMV specific T cell response in patients with already established CMV immunity. In 24 seropositive living donor kidney recipients, the frequency of CMV specific T cells was determined by ELISPOT (Enzyme-Linked ImmunoSpot) assay prior and 6 months after transplantation. Recipients’ peripheral blood mononuclear cells were stimulated with immediate-early (IE1) and phosphoprotein 65 (pp65) CMV-derived peptide pools and the number of cells producing interferon gamma (IFN-γ) was assessed. Patients received quadruple immunosuppression based either on depletive rabbit antithymocyte globulin (rATG) or non-depletive basiliximab induction and tacrolimus/mycophenolate mofetil/steroids. Patients with rATG induction received valgancyclovir prophylaxis. No effects of different induction agents on CMV specific T cell immunity were found at sixth month after kidney transplantation. There were no associations among dialysis vintage, pretransplant CMV specific T cell immunity, and later CMV DNAemia. Similarly, no effect of CMV prophylaxis on CMV specific T cell immunity was revealed. This study shows no effect of posttransplant immunosuppression on CMV specific T cell immunity in living donor kidney transplant recipients with CMV immunity already established, regardless of lymphocyte depletion and CMV prophylaxis., L. Stranavová, P. Hrubá, E. Girmanová, I. Tycová, A. Slavčev, J. Fronek, J. Slatinská, P. Reinke, H.-D. Volk, O. Viklický., and Seznam literatury