Elevated CO2 concentration (700 cm3 m-3, EC) inhibited chill-dependent (7 °C) depression of net photosynthetic rate of two maize hybrids with different sensitivity to low temperature. The rate of superoxide radical formation in leaves, leaf membrane injury, and the decrease in maximal quantum efficiency of photosystem 2 were successfully diminished by the treatment. The protective effect of EC toward stress conditions was prolonged at the recovery phase (20 °C). The genotypic impact on studied parameters was also notable. and R. Bączek-Kwinta, J. Kościelniak.
Michal Bauer, Jana Cahlíková, Dagmara Celik Katreniak, Julie Chytilová, Lubomír Cingl, and Tomáš Želinský., Obsahuje bibliografii a bibliografické odkazy, and České a anglické resumé
The changes of the composition of blood lipoproteins caused by menopause could also change the effect of hypolipidemic therapy. Using an experimental model we studied the changes of serum lipids and the effect of immediate or delayed treatment with simvastatin on atherosclerosis after surgical menopause. Female golden Syrian hamster aged 6 months were fed hypercholesterolemic diet during the whole study. Atherosclerotic changes in thoracic and abdominal aortas were assessed by stereomicroscopic method after 12 weeks. Four experimental groups were studied: sham-operated animals (n=5), ovariectomized animals (n=9), ovariectomized animals treated for 12 weeks (n=10), and ovariectomized animals treated 4 weeks after ovariectomy for 8 weeks (n=9). The dose of simvastatin was 10 mg/kg of body weight. After 12 weeks, ovariectomized animals had tenfold higher concentration of triglycerides in LDL fraction and significantly higher prevalence of atherosclerosis than animals without ovariectomy. Treatment with simvastatin substantially decreased the prevalence of atherosclerotic changes, but otherwise did not change individual serum lipids including LDL cholesterol. However, it improved proportions of pro- and antiatherogenic serum lipids mainly by the increase of HDL cholesterol. The timing of simvastatin treatment had no significant effect on atherosclerotic changes or lipid parameters. Simvastatin treatment partly prevented atherosclerotic changes induced by ovariectomy. This effect was not mediated by decrease of LDL cholesterol, but by increase in HDL cholesterol., J. Pitha ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Binding of beta2-GP I to anionic phospholipids is thought to be the major antigen required in the reaction of anticardiolipin antibodies to phospholipids. The aim of this study was to investigate the changes of anti-beta2-GP I IgG during the first and second trimester of pregnancy and the relationship between the levels of anti-beta2-GP I and fetoplacental antigens and the correlation between anti-beta2-GP I IgG and antibodies against oxidized low-density lipoprotein IgG (oLAb) in serum of pregnant women. We determined anticardiolipin antibodies (ACA) IgG and maternal serum levels of alpha1-fetoprotein (AFP), human chorionic gonadotrophin (HCG) and trophoblast-specific beta1-glycoprotein (SP1) in 204 pregnant women in the first and second trimester. From this group we selected 52 serum samples positive for ACA IgG and 16 samples negative for ACA IgG. In the samples of selected patients, the levels of anti-b2-GP I IgG and oLAb IgG were determined. Anti-b2-GP I IgG levels significantly decreased in the second trimester (6.2±9.3 U/ml, mean ± S.D.) in comparison with the first trimester (8.3±10.4 U/ml) (p=0.05). Multiple of median (MoM) AFP correlated negatively but not significantly in the first trimester with anti-b2-GP I (r = -0.261, p = 0.12). In the second trimester this correlation was significantly negative (r = -0.278, p = 0.04). The Spearman correlation coefficients for MoM HCG and anti-beta2-GP I were 0.158 for the first trimester and 0.174 for the second trimester. MoM SP1 also did not correlate significantly with anti-beta2-GP I in both trimesters. The correlation between anti-beta2-GP I IgG and oLAb IgG was not significant (r = -0.06). In the first trimester 40 % serum samples were positive for anti-b2-GP I IgG and negative for oLAb IgG or vice versa, while 60 % samples in the second trimester were positive only for one determined autoantibody. We can conclude that the levels of a, L. Fialová, I. Malbohan, L. Mikulíková, O. Benešová, A. Zwinger., and Obsahuje bibliografii
a1_Modification of low density lipoprotein (LDL) particles due to oxidation, glycation and binding of advanced glycation end-products (AGEs) or malondialdehyde (MDA, a final product of lipid peroxidation) is considered most important in the process of atherogenesis. Oxidatively modified LDL are distinguished by another receptor type, which was discovered on the surface of macrophages and was called the scavenger receptor. Uncontrolled intake of LDL converts macrophages to foam cells; their accumulation under the vascular endothelium is considered as the first stage of atherosclerosis. Oxidation of LDL is a complex process taking place in both the extra- and intracellular space. At the end of this oxidative process, modified LDL particles show chemotactic, cytotoxic and immunogenic properties. Oxidized LDL express a large number of epitopes and cause production of polyclonal autoantibodies against these products, especially against apoB100 modified by MDA and 4-hydroxynonenal. IgoxLDL (antibodies against oxidized LDL) can be demonstrated either directly in intimal lesions or as a component of circulating immune complexes. IgoxLDL do not form a homogeneous group but a varied mixture of antibodies-isoantibodies caused by HDL and LDL polymorphism, antibodies against the lipid phase of LDL and antibodies against modified apoB100 of the immunoglobulin class IgA or IgG. Antibodies against oxLDL were found in many diseases other than atherosclerosis such as diabetes mellitus, renovascular syndrome, uremia, rheumatic fever, morbus Bechtjerev or lupus erythematodes. Newborns have practically the same levels of IgoxLDL as their mothers; however, these values did not differ from those in the healthy population of non-pregnant women of the same age., a2_The decrease in IgoxLDL titer was very slow and lasted many months; that is why this parameter cannot be considered suitable for describing the rapid changes during oxidative stress of the organism. Positive correlation of IgoxLDL with antiphospholipids and other antibodies was repeatedly demonstrated; their determination can thus be used as a marker for the description of total production of autoantibodies in various diseases. The changes and correlations of IgoxLDL, anti-b-2-glycoprotein I IgG and antiphospholipid antibodies support the immunological link between thrombotic and atherosclerotic processes in the human body., A. Steinerová, J. Racek, F. Stožický, T. Zima, L. Fialová, A. Lapin., and Obsahuje bibliografii
a1_Oxidized low density lipoproteins (oxLDL) formed in vivo induce a humoral immune response. Oxidative modification of LDL renders it immunogenic and a heterogeneous population of specific anti-oxLDL antibodies is produced. These antibodies could represent a biological marker of oxidative stress and serve as markers of atherosclerosis. Autoantibodies against oxLDL (oLAb) have been detected in human subjects practically of every age. oLAb also appear in the blood of pregnant women. Some studies have shown that the levels of antibodies to oxLDL were elevated in women with established preeclampsia. The present study was aimed to estimate the oLAb IgG levels in the first and second trimester of pregnancy. Furthermore, we estimated the correlation between maternal serum (MS) levels of oLAb and alpha-1-fetoprotein (MS AFP), human chorionic gonadotrophin (MS HCG) and trophoblast-specific-beta-1-glycoprotein (MS SP1), because these proteins are determined as a part of prenatal biochemical screening for fetal congenital abnormalities. Our study deals with the oLAb changes in women with pregnancy-induced hypertension. We also investigated the correlation between oLAb IgG and anticardiolipin antibodies IgG (ACA) in the serum of pregnant women. We examined 40 pregnant women attending Institute for Mother and Child Care for their antenatal care as outpatients. Routine blood samplings between the 9-13th week of pregnancy and 16-18th week of pregnancy were performed as a part of biochemical prenatal screening for fetal congenital abnormalities (Group 1). Their mean age was 27±4.1 years. Furthermore, we examined 26 women in the second or third trimester with pregnancy-induced hypertension (Group 2). Group 2 was compared with 49 pregnant women in the second or third trimester who were normotensive (Group 3)., a2_We used commercial standardized ELISA kits for determination of oLAb IgG, ACA IgG, MS AFP and MS HCG, MS SP1 was analyzed by single radial immunodiffusion. We did not find any differences in the levels of oLAb IgG in the first and second trimester in the women of Group 1. The correlation between oLAb and ACA IgG was not statistically significant (Spearman coefficient r=0.22, p=0.1). The correlation between oLAb IgG with MS AFP, MS HCG and MS SP1 was not statistically significant. Weak negative correlation for AFP and HCG was suggested both in the first and in the second trimester. The levels of oLAb IgG in the group of women with pregnancy-induced hypertension were significantly lower than in the group of normotensive women (348±388 U/ml v.s. 579±400 mU/ml, p<0.01). We can conclude that the levels of oLAb do not differ in the first and second trimester of gravidity. However, we cannot exclude the possible influence of an inverse relationship between oLAb IgG titers and the synthesis of fetoplacental antigens. This finding is important especially in the context of the results of prenatal biochemical screening. Pregnancy-induced hypertension is associated with lower levels of oLAb. Weak cross-reactivity between oLAb and anticardiolipin antibodies may exist but there is a possibility that there are two different populations of antibodies reacting with various antigens., L. Fialová, L. Mikulíková, I. Malbohan, O. Benešová, S. Štípek, T. Zima, A. Zwinger., and Obsahuje bibliografii
Antiphospholipid antibodies (APA) are a generic term describing antibodies that recognize various phospholipids. Hepatocyte damage is a cardinal event in the course of alcoholic liver injury and autoantibodies against phospholipids could play an important role in this process. APA in alcoholic patients seem to reflect membrane lesions, impairment of immunological reactivity, liver disease progression and they correlate significantly with disease severity. LDL oxidation is supposed to be one of the most important pathogenic mechanisms of atherosclerosis and antibodies against oxidized low-density lipoprotein (oxLDL) are some kind of an epiphcnomenon of this process. The scope of our study was to determine some autoantibodies (IgG-oxLDL and antiphospholipid antibodies) and their possible changes in alcoholic patients. We studied IgG-oxLDL and four APA - anticardiolipin antibodies (ACA), antiphosphatidylserine antibodies (APSA) antiphosphatidyl- ethanolamine antibodies (APE) and antiphosphatidylcholine antibodies (APCA) in 35 alcoholic patients with mildly affected liver function at the beginning of the abuse treatment. The control group consisted of 60 healthy blood donors. In the studied group, we obtained positive results concerning total ACA in 17.1 % of alcoholic patients (8.3% in the control group), 11.4% IgG-ACA (6.7%), 8.6% IgM-ACA (3.3%), 14.3% total APE (6.7 %), 14.3 % total APCA (8.3 %) and 20 % total APSA (8.3 % in the control group). The IgG-oxLDL (406.4 ±52.5 vs 499.9 ±52.5 mU/ml) was not affected in alcoholic patients. We conclude that the autoantibodies against oxLDL are present in sera of alcoholics and healthy blood donors. Based on our results which revealed a wide range of IgG-oxLDL titres in the healthy population, this parameter does not appear to be very promising for the evaluation of the risk of atherosclerosis. Alcoholics with only mild affection of liver functions did not exhibit a significantly higher prevalence of all studied antiphospholipid antibodies (ACA, APSA, APE, APCA) which could lead to membrane lesions in these patients.
Antibody-mediated rejection (ABMR) is a major obstacle to the long-term success in kidney transplantation. Diagnosis of ABMR is determined according to the internationally recognized Banff criteria. However, a significant proportion of patients does not meet all the defined criteria, and the outcome of such cases remains poorly understood. The histology of ABMR frequently lacks sensitivity and specificity. More importantly, mixed forms of ABMR and T cell-mediated rejection as well as findings of nonspecific injury are common in clinical settings. Donor-specific anti-HLA antibodies (DSA) are detectable only in half of the ABMR cases by histology. Prognostic role of non-HLA antibodies against various endothelial proteins has been discussed. Antibody independent NK cell activation reflecting killer-cells’ inhibitory receptor incompatibility is suggested in microvascular inflammation in DSA negative patients. Molecular assessment of ABMR has been prioritized to overcome high interobserver variability and improve diagnostics in mixed forms of rejections and in DSA negative cases. Finally, donor-derived cell-free DNA detected in a recipient’s peripheral blood sample has been proposed as a noninvasive marker for diagnosis of graft rejection, and thus might serve as a liquid biopsy in the near future. Despite all achievements, diagnosing ABMR in kidney allografts remains to be a challenge in a significant number of cases.