Replacing SAFAs (saturated fatty acids) for vegetable PUFAs (polyunsaturated fatty acids) has a well documented positive effect on the lipoprotein pattern while the direct effect of dietary fatty acids composition on systemic inflammation remains to be proven. In well controlled randomised cross-over study with 15 overweight/obese postmenopausal women, the effect of dietary switch on systemic inflammation was investigated. A two 3 weeks dietary period either with predominant animal fat (SAFA, 29 caloric % SAFA) or vegetable fat (PUFA 25 % caloric % PUFA) were interrupted by wash-out period. The expected increasing effect on SAFA diet to LDL-C (low density cholesterol) and opposite effect of PUFA diet was documented following changes in fatty acid spectrum in VLDL (very low density cholesterol) particles. The switch from SAFA diet to PUFA diet produced a significant change of CRP (C-reactive protein) concentration (p<0.01) whereas similar trend of IL-18 did not reach statistical significance. In this study, previous in vitro results of different SAFA and PUFA proinflammatory effects with well documented molecular mechanisms were first proven in a clinical study. It could be stated that the substantial change of dietary fatty acid composition might influence proinflammatory effect in addition to traditional cardiovascular risk factors., I. Králová Lesná, ... [et al.]., and Obsahuje seznam literatury
In this study we have compared the adhesion of peripheral blood mononuclear cells (PBMC) to human umbilical vein endothelial cells (HUVEC) in a healthy control group with two groups of allergic asthmatics, not treated or treated with disodium cromoglycate (DSCG). The adhesion and blocking experiments were performed by the flow cytometric adhesion assay. No differences in the adhesion of lymphocytes were observed in any of the groups. The monocytes obtained from DSCG non-treated patients have shown significant (P<0.05) enhancement of adhesion to HUVEC in comparison to healthy controls. The treatment of asthmatic patients with DSCG downregulated the monocyte adhesion to cultured endothelial cells (ECs) and this was comparable to the group of normal donors. The DSCG may have a therapeutic effect on the regulation of monocyte adhesion in inflammatory and allergic diseases. The binding ability of untreated asthmatic PBMC to cultured ECs was partially inhibited by monoclonal antibody anti-CD54, suggesting that the increased EC adhesiveness for monocytes from allergic asthmatics may be at least partially dependent on the ICAM-1 adhesion pathways. Our results also indicate that the blocking agent anti-CD 18 was not essential for monocyte- endothelial interactions in allergic asthma.
Various stages in the succession of vegetation of peat bogs following disturbance were studied in the Třeboň Basin, Czech Republic. The disturbance was of two types: (a) natural, represented by windthrow, with subsequent bark beetle attack, and fire, and (b) human-made peat digging and industrial peat milling. The species composition at different stages in succession following disturbance were compared with that in undisturbed plots. Regeneration of peat bog vegetation was faster after a natural than after human-made disturbance. The lowest impact was caused by windthrow, followed by fire. Regeneration after peat digging took much longer. Regeneration after industrial peat harvesting only occurred if the groundwater table level remained high.
The rubber tree (Hevea brasiliensis) is an important tropical crop with a high economic value that has been successfully cultivated in Xishuangbanna, China. Xishuangbanna has a long dry season (November-February) with cold nights and frequent fog events. Thus, it is important to select chilling-tolerant cultivars in order to understand better the role of fog in protecting rubber tree from chilling-induced photodamage. In this study, we examined the photosynthetic responses of six rubber tree cultivars (Lan 873, Yunyan 77-2, Yunyan 77-4, GT1, Reken 523, and Reyan 733-97) to night-chilling stress (0, 5, and 10°C) and two different irradiances (100 and 50% of full sunlight). Our results showed that all six cultivars could withstand nights at 10°C for three days, while night chilling at 0 and 5°C impaired photosynthesis, which was indicated by photoinhibition, decrease of soluble protein content, and accumulation of malondialdehyde. Reken 523 and Reyan 733-97 were more sensitive to night chilling than other cultivars. Low irradiance (50% of full sunlight) after the chilling treatment apparently mitigated the effect of night-chilling stress. It indicates that frequent fog events after cold nights might greatly contribute to the success of rubber tree cultivation in Xishuangbanna., Y.-H. Tian, H.-F. Yuan, J. Xie, J.-W. Deng, X.-S. Dao, Y.-L. Zheng., and Seznam literatury
Objectives: The aim of this study was to elucidate the role of dopamine receptor D2 / ankyrin repeat and protein kinase domain containing 1 (DRD2/ANKK1) TaqIA allelic polymorphism in the HPVinduced cervical carcinogenesis. Methods: 1. Effect on the risk of cervical precancer: After an 8year followup, out of 214 women with persisting highrisk HPV infection, 102 developed highgrade cervical dysplasia or cervical intraepithelial neoplasia (CIN) grade III, while 112 did not. The subjects were genotyped for the DRD2/ANKK1 TaqIA polymorphism by PCRRFLP, and the allelic distributions were compared between groups with and without highgrade dysplasia. 2. Prognostic value: Two hundred and thirty nine women with cervical precancer/cancer were followed for 5 years. Complete remission was achieved at 182 women. To assess the prognostic value of the TaqIA polymorphism, genotype frequencies were compared between patients reaching and not reaching complete remission. Results: The frequency of A1/A1+A1/A2 genotypes was higher among women who developed highgrade cervical dysplasia (OR: 1.87, 95% CI: 1.053.33; p=0.034) than in the other group. Occurrence of the A1 allele was more frequent among women who did not reach complete remission (OR: 2.00, 95% CI: 1.073.74; p=0.030) than in women with complete remission. Conclusions: This is the first report on the possible involvement of DRD2/ANKK1 TaqIA polymorphism in cervical carcinogenesis. The A1 allele seems to increase the risk of cervical precancer, and it may also be associated with a worse prognosis in women with HPVinduced cervical cancer. The results need further validation in largescale molecular epidemiological studies., József Cseh, Zsuzsa Orsós, Emese Pázsit, Erika Marek, András Huszár, István Ember, István Kiss, and Literatura
We investigated net photosynthetic rate (PN) of ear and two uppermost (flag and penultimate) leaves of wheat cultivars Hongmangmai (drought resistant) and Haruhikari (drought sensitive) during post-anthesis under irrigated and non-irrigated field conditions. The PN of ear and flag leaf were significantly higher and less affected by drought in Hongmangmai than in Haruhikari. The rate of reduction in stomatal conductance (gs) was similar for the two cultivars, but intercellular CO2 concentration (Ci) in the flag leaf of Hongmangmai was lower than that of Haruhikari in non-irrigated treatment. No differences were observed in leaf water potential (ψ1) and osmotic adjustment of the flag leaf of the cultivars. These results imply that differences in photosynthetic inhibition on the flag leaf at low leaf ψ1 between the cultivars were primarily due to non-stomatal effects. Hence the main physiological factor associated with yield stability of Hongmangmai under drought stress may be attributed to the capacity for chloroplast activity in the flag leaf, which apparently allows sustained PN of flag leaf during grain filling under drought stress. The higher PN of ear in Hongmangmai under drought could also be related to its drought resistance. and T. Inoue ... [et al.].
Development of water stress in Trifolium subterraneum L. plants, growing in growth room or in the field during autumn-winter and latě springtime, was studied under ťhe conditions of irrigation replenishing every day the evaporated water (1), withholding watering (WW), and slowly induced drought, replenishing daily with a fraction of water evaporated (SID). The method ušed to induce drought substantially affected the leaf water relations. In WW plants drought developed rapidly and in consequence the leaf water relations dramatically changed afler 10 d of treatment. The treatment maintained a stable moderate water stress (SID) that enabled the development of new acclimated leaves even under high tempertures and low humidity.
The CO2 assimilation rate the transpiration rate (E), the stomatal conductance (gg), C index and the instantaneous water use efficiency of attached leaves háve been estimated in sixteen cultivars of subterranean clover (Trifolium subterraneum L.) fíeld growing plants, both irrigated and subjected to water stress, during latě spring in Mallorca, Spain. Variability among the genotypes with regard to the and other related parameters was highly significant for tiie irrigated plants. Drou^t promoted a marked decrease in both gg and ®ven when the relative water content of leaves was only slightly decreased. For water-stressed plants, genotypic variability in E and C index was also statistically significant. However, variability among the genotypes with regard to gg and was no longer evident under drought. The C index might represent a valuable parameter for evaluation of the genotypic responses of plants to drought.
The effect of a short (7 d), prolonged (14 d) soil drought (D) and (7 d) recovery (DR) on the leaf optical properties - reflectance (R), transmittance (T) and absorptance (A) in photosynthetically active radiation (PAR) and near infrared radiation (NIR) range of irradiation (750-1100 nm) was studied for maize and triticale genotypes differing in drought tolerance. The drought stress caused the changes in leaf optical properties parameters in comparison with non-drought plants. The observed harmful influence of drought was more visible for maize than triticale. and M. T. Grzesiak ... [et al].
Water stress usually impairs photosynthesis and plant growth. Acacia tortilis subsp. raddiana is well adapted to dry environments. The aim of the present study was to determine the impact of a progressive decrease in soil water content on photosynthetic-related parameters at the young seedling stage. Drought-induced plant responses occurred according to two types of kinetics. Water potential, stomatal conductance, and transpiration rates were rapidly affected by a decrease in soil water content, while chlorophyll fluorescence-related parameters and chlorophyll concentrations decreased only when soil water content was lower than 40%. The maximal efficiency of PSII photochemistry in the dark-adapted state remained unaffected by the treatment, whatever the stress duration. A. raddiana accumulated high concentrations of soluble sugars in relation to a stress-induced early stimulation of sucrose-phosphate synthase activity, while stimulation of invertase and sucrose synthase led to fructose accumulation only at the end of the stress period. We suggested that sugar accumulation may be involved in osmotic adjustment and protection of stressed tissues. A. raddiana was thus able to protect its photosynthetic machinery under drought conditions and may be considered as a promising species for revegetation of dry areas., S. Kebbas, S. Lutts, F. Aid., and Obsahuje bibliografii