The effect of water stress on the gas exchange (CO2, H2O), distribution, water potential (T*), membrane permeability and chlorophyll content was studied in two maize hybrids, of the high and low drought tolerance, in the vegetative phase of growth. Diťferences in the responses to drought between both hybrids were clearly marked. After 5 d of drought the decrease in the net photosynthetic rate uptake and losses, transpiration rate (E) and increase of stomata resistance (r^ were greater in the drought-resistant hybrid than in the drought-susceptible one. On the contrary, after 10 or 15 d of drought, the decrease of and 'P in whole seedlings was greater in the susceptible hybrid than in the resistant one. Significant differences between hybrids were also observed in the accumulation of *'^C, the membrane permeability and the chlorophyll content. For all treatments the amount of carbon accumulation in roots of the resistant hybrid increased, while that of the susceptible one decreased. In the drought-resistant hybrid we observed a greater chlorophyll stability and a smaller damage of cell membranes than in the sensitive one.
Dyslipidemia is the risk fact or of cardiovascular disease, but the relationship between the plasma triglyceride (TG) levels and total/cardiovascular mortality has not yet been analy zed in Slavs. The aim of our study was to analy ze the association between the fasting TG levels and all- cause/cardiovascular mortality. We have examined 3,143 males and 3,650 females, aged 58.3±7.1 years. 729 deaths (274 cardiovascular deaths) have been registered during up to 11.8 years of follow -up. Age -sex adjusted all -cause mortality was higher in individuals with TG values 3.01 -4.00 mmol /l (HR 1.37, 95 % CI 1.02- 1.83, P=0.035) and over 4.00 mmol /l (HR 1.66, 95 % CI 1.21 -2.27, P=0.002) when compared with a reference group (TG 1.41 -1.80 mmol /l). Elevated risk remains significant when adjusted for education, marital status and unemployment. When further adjusted for smoking, BMI and dyslipidemia interventions, HR for those in above 4.00 mmol/l group decreas ed (1.42, P=0.04). The results have been similar when cardiovascular mortality has been examined, however, results reached statistical significance only for the TG over 4.0 mmol /l (P=0.028). Our results confirmed that enhanced plasma levels of plasma triglycerides are dose dependently associated with increased risk of all- cause mortality, however, it s eems that individuals with TG values 1.8 -3.0 mmol /l are not in higher risk of death., H. Pikhart, J. A. Hubáček, A. Peasey, R. Kubínová, M. Bobák., and Obsahuje bibliografii
The aim of this study was to evaluate the association of A1166C polymorphism in angiotensin II type 1 receptor (AT1R) gene with baroreflex sensitivity (BRS in ms/mm Hg; BRSf in mHz/mm Hg) in man. BRS and BRSf were determined by a spectral method in 135 subjects (19-26 years) at a frequency of 0.1 Hz. Genotypes were detected by means of polymerase chain reaction and restriction analysis using enzyme DdeI. We compared BRS and BRSf among genotypes of this polymorphism. The frequency of genotypes of AT1R A1166C polymorphism was: 45.9 % (AA, n=62), 45.9 % (AC, n=62), 8.2 % (CC, n=11). Differences in BRS (p<0.05) and BRSf (p<0.01) among genotypes of this single nucleotide polymorphism were found (Kruskal-Wallis: BRS - AA: 7.9±3.3, AC: 8.6±3.6, CC: 5.9±2.3 ms/mm Hg; BRSf - AA: 12.0±4.0, AC: 12.0±5.0, CC: 8.0±3.0 mHz/mm Hg). Compared to carriers of other genotypes (AA+AC) the homozygotes with the less frequent allele (CC) showed significantly lower BRSf (Mann-Whitney: BRSf - AA+AC: 12.0±4.0, CC: 8.0±3.0 mHz/mm Hg; p<0.01) and borderline lower BRS (BRS - AA+AC: 8.2±3.5, CC: 5.9±2.5 ms/mm Hg; p=0.07). We found a significant association of A1166C polymorphism in AT1 receptor gene with baroreflex sensitivity. Homozygosity for the less frequent allele was associated with decreased baroreflex sensitivity., M. Jíra ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Both, common gene variants and human adenovirus 36 (Adv36) are involved in the pathogenesis of obesity. The potential relationship between these two pathogenic factors has not yet been investigated. The aim of our study was to examine the association of obesity susceptibility loci with Adv36 status. Genotyping of ten gene variants (in/near TMEM18, SH2B1, KCTD15, PCSK1, BDNF, SEC16B, MC4R, FTO) and analysis of Adv36 antibodies was performed in 1,027 Czech adolescents aged 13.0-17.9 years. Variants of two genes (PCSK1 and BDNF) were associated with Adv36 seropositivity. A higher prevalence of Adv36 antibody positivity was observed in obesity risk allele carriers of PCSK1 rs6232, rs6235 and BDNF rs4923461 vs. noncarriers (χ2=6.59, p=0.010; χ2=7.56, p=0.023 and χ2=6.84, p=0.033, respectively). The increased risk of Adv36 positivity was also found in PCSK1 variants: rs6232 (OR=1.67, 95 % CI 1.11-2.49, p=0.016) and rs6235 (OR=1.34, 95 % CI 1.08-1.67, p=0.010). PCSK1 rs6232 and BDNF rs925946 variants were closely associated with Adv36 status in boys and girls, respectively (χ2=5.09, p=0.024; χ2=7.29, p=0.026). Furthermore, PCSK1 rs6235 risk allele was related to Adv36 seropositivity (χ2=6.85, p=0.033) in overweight/obese subgroup. In conclusion, our results suggest that obesity risk variants of PCSK1 and BDNF genes may be related to Adv36 infection., L. Dušátková, H. Zamrazilová, I. Aldhoon Hainerová, R. L. Atkinson, B. Sedláčková, Z. P. Lee, J. Včelák, B. Bendlová, M. Kunešová, V. Hainer., and Obsahuje bibliografii
Present study aimed to explore the levels and correlation of oxidative stress biomarkers with anthropometry in a population of young Saudi females. One hundred six normotensives, non-diabetic Saudi females, with minimally active lifestyle, based on their body mass index (BMI) were divided as; normal-weight (NW; n=52), overweight (OW; n=24) and obese (OB; n=30). Anthropometric measurements [BMI, Waist Circumference (WC), Waist-Hip Ratio (WHR), Body Density (BD), Body Adiposity Index (BAI), % Body fat] and oxidative stress biomarkers; Thiobarbituric acid reactive substances (TBARS), 8-hydroxy-2- deoxyguanosine (8-OH-2dG: indicative of DNA/RNA damage), Superoxide dismutase, Serum total antioxidant capacity) were recorded. There was statistically significant higher 8-OH-2dG (pg/ml) in OB compared to NW (800.63±6.19 vs. 780.22±3.34; p=0.007), as determined by one-way ANOVA and Tukey post hoc test. 8-OH-2dG was significantly and positively associated with BMI (r=0.286, p=0.004), WC (r=0.280, p=0.005), BAI (r=0.26, p=0.008), and % body fat (r=0.27, p=0.006). There may be significantly increased DNA damage in normoglycemic, normotensive obese adolescent females. This can be linked to the amount of adipose tissue in the body as depicted by strong positive association between DNA damage and BMI, WC, BAI, and % body fat., R. Latif, N. Rafique., and Obsahuje bibliografii
The LRP5 gene is believed to be primarily associated with bone metabolism via Wnt signaling. The latter pathway, however, appears to control various other systems outside the skeleton. To find the relationships of the LRP5 gene to serum follicle stimulating hormone (FSH ) and luteinizing hormone (LH) in the cohort of normal postmenopausal women, we identified the C/T (c.4037:A1330V) polymorphism in the LRP5 gene using a restriction analysis of the PCR product in a cohort of 165 untreated pre- and post-menopausal women. In a subset of 111 post-menopausal women we analyzed the association between the LRP5 genotype and serum levels of sex-hormones including FSH and LH. The distribution of CC, TC and TT genotypes of the C/T polymorphism in the whole group was 73.9 %, 23.6 % and 2.4 %, respectively, which is comparable with other Caucasian populations. As no TT homozygote was found in the group of post-menopausal women, serum sex-hormones were compared between CC and TC genotypes. Women with the CT allele combination had markedly higher serum FSH levels as compared to carriers of the CC genotype (p<0.004). No differences between these genotypes were found in serum LH levels as well as the circulating sex-steroids such as estradiol, testosterone, dehydroepiandrosterone and/or its sulphate, androstenedione and SHBG. To conclude, the LRP5 gene is associated with circulating FSH in normal post-menopausal women in the present study. The mediating role of subtle undetectable variations in estrogen levels is discussed. We did not find any relationship between the LRP-5 genotype and serum LH levels., I. Žofková, M. Hill, K. Zajíčková., and Obsahuje bibliografii a bibliografické odkazy
The aim of this study was to evaluate the association of single nucleotide polymorphisms (SNPs) T-786C and G894T in the gene encoding eNOS with blood pressu re variability (BPV) in man. Blood pressure was recorded beat-t o-beat at rest three times in periods of one week (5 min, Finapres, breathing at 0.33 Hz) in 152 subjects (19-24 years). Systolic (SBPV0.1r/SBPV 0.1a) and diastolic (DBPV0.1r/DBPV 0.1a) blood pressure variabilities in relative (r.u.) and absolute (mmHg2/Hz) units were determined by the spectral method as spectral po wer at the frequency of 0.1 Hz. Genotypes of both polymorphisms were detected using polymerase chain reaction and re striction analysis using enzymes Msp I and Ban II. Significant diffe rences were observed in BPV among genotypes of T-786C SNP (p<0.05; Kruskal-Wallis), and among haplotypes of both SNPs (p<0.05; Kruskal-Wallis) as well. In T-786C SNP, carriers of less frequent allele (CC homozygotes and TC heterozygotes) showed significantly greater SBPV0.1r and SBPV0.1a compared to TT homozygote s (Mann-Whitney; p<0.05). The G894T variant showed no sign ificant differences, but, both SNPs were in linkage disequilib rium (D’=0.37; p<0.01). Carriers of haplotype CT/CT (CC homozygotes of -786C/T and TT homozygotes of G894T) displaye d significantly greater SBPV0.1r, SBPV0.1a and DBPV0.1a compared to carriers of other haplotype combinations (Kruskal-Wallis; p=0.015, p=0.048, and p=0.026, respectively). In conclusion, the haplotype formed by less frequent alleles of both eNOS variants was associated with increased systolic and diastolic BPV in this study., M. Jíra ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
A predominance of small, dense low-density lipoproteins (LDL) is characteristic of the dyslipidemic state seen in type 2 diabetes. However, no study has investigated the association in gestational diabetes mellitus (GDM), which is pathophysiologically similar to type 2 diabetes. We hypothesized that LDL particle size is reduced in GDM cases compared with controls. Gradient gel electrophoresis was used to characterize LDL subclass phenotypes in non-fasting intrapartum plasma from 105 GDM cases and 96 controls. All participants were free of pre-existing diabetes or hypertension. The authors used logistic regression to estimate odds ratios (OR) and 95 % confidence intervals (CI) adjusted for confounders. Women with this phenotype had a significant 4.9-fold (95 % CI: 1.1-23.2) increased risk of GDM compared with those with the large, buoyant phenotype. The magnitude of this association was attenuated when plasma triglyceride and other confounders were included in the model (OR=4.2, 95 % CI: 0.5-39.5). Mean LDL particle size in GDM cases was smaller compared with controls (270.1 vs. 272.7Å, p=0.003). The OR of GDM risk was 1.8 (95 % CI: 0.9-3.3) for every 10-Å reduction in LDL particle size. Large prospective studies are needed to evaluate the association between smaller LDL particle size in early pregnancy with subsequent GDM risk., C. Qiu, C. Rudra, M. A. Austin, M. A. Williams., and Obsahuje bibliografii a bibliografické odkazy
The subclass of triglyceride -rich lipoproteins - remnant -like particles (RLP) seems to be strong and independent risk factor for cardiovascular disease. We eva luated the role of RLP and other risk factors (RF) with sonographically measured intima - media thickness of carotid arteries (IMT CCA) in a cohort of Czech population including women defined according to the time after menopause. We investigated relation of IMT CCA to age, weight, central obesity, plasma lipids including remnant -like particles cholesterol (RLP -C) and triglycerides (RLP -TG) in 136 men and 160 women. Using multiple linear regression analysis, significant association between IMT CCA and RLP -C was found in women 1 -7 years after menopause. In the whole group of women, only age and fasting blood glucose were independently associated with IMT CCA. In men only age significantly correlated wit h IMT CCA. Significant decrease of all plasma lipids betwe en 1988 and 1996 in men was detected, while in women significant increase in triglycerides and no change in non -HDL cholesterol was observed. RLP -C was the strongest independent RF for atherosclerosis in postmenopausal women but its as sociation with IMT CC A was limited to several years after menopause. In conclusion, women changing reproductive status could be more sensitive to atherogenic impact of remnant lipoproteins., J. Piťha, J. Kovář, Z. Škodová, R. Cífková, P. Stávek, L. Červenka, T. Šejda, V. Lánská, R. Poledne., and Obsahuje bibliografii
We assessed association between novel biomarkers of cardiovascular disease and conven tional factors in 40 years old subjects (208 men and 266 women) from the general population of Slovakia. FER HDL (cholesterol esterifi cation rate in HDL plasma), AIP - Atherogenic Index of Plasma [Log(TG/HDL-C)] as markers of lipoprotein particle size, and CILP2, FTO and MLXIPL polymorphisms, were examined in relation to biomarkers and conventional risk factors. Un ivariate analyses confirmed correlation between AIP, FERHDL and the most of measured parameters. Relations between AIP and CILP2, FTO and MLXIPL were not significant. However, CILP2 was significantly related to FERHDL in both genders. In multivariate analysis BMI was the strongest correlate of AIP levels. In multivariate model variability of FER HDL was best explained by AIP (R2 =0.55) in both genders with still significant effect of CILP2 SNP in men. In a model where AIP was omitted, TG leve ls explained 43 % of the FER HDL variability in men, while in women HDL-C was the major determinant (42 %). In conclusions, FERHDL and AIP related to the known markers of cardiovascular risk provide means to express their subtle interactions by one number. Our novel finding of association between CILP2 polymorphism and FERHDL supports its role in lipid metabolism., K. Rašlová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy