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11.
Matić Ivana Z. Ergün Sercan Đorđić Crnogorac Marija Misir Sema Aliyazicioğlu Yüksel Damjanović Ana Džudžević-Čančar Hurija Stanojković Tatjana Konanç Kalbiye Petrović Nina 《Cytotechnology》2021,73(3):373-389
Cytotechnology - Six extracts were obtained from plant species Hypericum perforatum L., collected at Samsun in Turkey. The aim of this study was to examine the mechanisms of the anticancer activity... 相似文献
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Danijela Krstić Katarina Krinulović Vesna Vasić 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):469-476
Kinetics and inhibition of Na+/K+-ATPase and Mg2+-ATPase activity from rat synaptic plasma membrane (SPM), by separate and simultaneous exposure to transition (Cu2+, Zn2+, Fe2+ and.Co2+) and heavy metals (Hg2+and Pb2+) ions were studied. All investigated metals produced a larger maximum inhibition of Na+/K+-ATPase than Mg2+-ATPase activity. The free concentrations of the key species (inhibitor, MgATP2 ? , MeATP2 ? ) in the medium assay were calculated and discussed. Simultaneous exposure to the combinations Cu2+/Fe2+ or Hg2+/Pb2+caused additive inhibition, while Cu2+/Zn2+ or Fe2+/Zn2+ inhibited Na+/K+-ATPase activity synergistically (i.e., greater than the sum metal-induced inhibition assayed separately). Simultaneous exposure to Cu2+/Fe2+ or Cu2+/Zn2+ inhibited Mg2+-ATPase activity synergistically, while Hg2+/Pb2+ or Fe2+/Zn2+ induced antagonistic inhibition of this enzyme. Kinetic analysis showed that all investigated metals inhibited Na+/K+-ATPase activity by reducing the maximum velocities (Vmax) rather than the apparent affinity (Km) for substrate MgATP2-, implying the noncompetitive nature of the inhibition. The incomplete inhibition of Mg2+-ATPase activity by Zn2+, Fe2+ and Co2+ as well as kinetic analysis indicated two distinct Mg2+-ATPase subtypes activated in the presence of low and high MgATP2 ? concentration. EDTA, L-cysteine and gluthathione (GSH) prevented metal ion-induced inhibition of Na+/K+-ATPase with various potencies. Furthermore, these ligands also reversed Na+/K+-ATPase activity inhibited by transition metals in a concentration-dependent manner, but a recovery effect by any ligand on Hg2+-induced inhibition was not obtained. 相似文献
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Stephanie Melkonian Maria Argos Megan N. Hall Yu Chen Faruque Parvez Brandon Pierce Hongyuan Cao Briseis Aschebrook-Kilfoy Alauddin Ahmed Tariqul Islam Vesna Slavcovich Mary Gamble Parvez I. Haris Joseph H. Graziano Habibul Ahsan 《PloS one》2013,8(11)
Background
We utilized data from the Health Effects of Arsenic Longitudinal Study (HEALS) in Araihazar, Bangladesh, to evaluate the association of steamed rice consumption with urinary total arsenic concentration and arsenical skin lesions in the overall study cohort (N=18,470) and in a subset with available urinary arsenic metabolite data (N=4,517).Methods
General linear models with standardized beta coefficients were used to estimate associations between steamed rice consumption and urinary total arsenic concentration and urinary arsenic metabolites. Logistic regression models were used to estimate prevalence odds ratios (ORs) and their 95% confidence intervals (CIs) for the associations between rice intake and prevalent skin lesions at baseline. Discrete time hazard models were used to estimate discrete time (HRs) ratios and their 95% CIs for the associations between rice intake and incident skin lesions.Results
Steamed rice consumption was positively associated with creatinine-adjusted urinary total arsenic (β=0.041, 95% CI: 0.032-0.051) and urinary total arsenic with statistical adjustment for creatinine in the model (β=0.043, 95% CI: 0.032-0.053). Additionally, we observed a significant trend in skin lesion prevalence (P-trend=0.007) and a moderate trend in skin lesion incidence (P-trend=0.07) associated with increased intake of steamed rice.Conclusions
This study suggests that rice intake may be a source of arsenic exposure beyond drinking water. 相似文献16.
Djordje Malenčić Jelena Cvejić Vesna Tepavčević Mira Bursać Biljana Kiprovski Miloš Rajković 《Central European Journal of Biology》2013,8(9):921-929
Soybean [Glycine max (L.) Merr.] cultivars (Meli, Alisa, Sava and 1511/99) were grown up to V1 phase (first trifoliate and one node above unifoliate) and then inoculated with Sclerotinia sclerotiorum (Lib.) de Bary under controlled conditions. Changes in L-phenylalanine ammonia-lyase (PAL) activity and isoflavone phytoalexins were recorded 12, 24, 48 and 72 h after the inoculation. Results showed an increase in PAL activity in all four examined soybean cultivars 48 h after the inoculation, being the highest in Alisa (2-fold higher). Different contents of total daidzein, genistein, glycitein and coumestrol were detected in all samples. Alisa and Sava increased their total isoflavone content (33.9% and 6.2% higher than control, respectively) as well as 1511/99, although 48 h after the inoculation its content decreased significantly. Meli exhibited the highest rate of coumestrol biosynthesis (72 h after the inoculation) and PAL activity (48 h after the inoculation). All investigated cultivars are invariably susceptible to this pathogen. Recorded changes could point to possible differences in mechanisms of tolerance among them. 相似文献
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Ivan Soldatovic Rade Vukovic Djordje Culafic Milan Gajic Vesna Dimitrijevic-Sreckovic 《PloS one》2016,11(1)
Objective
To evaluate siMS score and siMS risk score, novel continuous metabolic syndrome scores as methods for quantification of metabolic status and risk.Materials and Methods
Developed siMS score was calculated using formula: siMS score = 2*Waist/Height + Gly/5.6 + Tg/1.7 + TAsystolic/130—HDL/1.02 or 1.28 (for male or female subjects, respectively). siMS risk score was calculated using formula: siMS risk score = siMS score * age/45 or 50 (for male or female subjects, respectively) * family history of cardio/cerebro-vascular events (event = 1.2, no event = 1). A sample of 528 obese and non-obese participants was used to validate siMS score and siMS risk score. Scores calculated as sum of z-scores (each component of metabolic syndrome regressed with age and gender) and sum of scores derived from principal component analysis (PCA) were used for evaluation of siMS score. Variants were made by replacing glucose with HOMA in calculations. Framingham score was used for evaluation of siMS risk score.Results
Correlation between siMS score with sum of z-scores and weighted sum of factors of PCA was high (r = 0.866 and r = 0.822, respectively). Correlation between siMS risk score and log transformed Framingham score was medium to high for age groups 18+,30+ and 35+ (0.835, 0.707 and 0.667, respectively).Conclusions
siMS score and siMS risk score showed high correlation with more complex scores. Demonstrated accuracy together with superior simplicity and the ability to evaluate and follow-up individual patients makes siMS and siMS risk scores very convenient for use in clinical practice and research as well. 相似文献18.
Vesna Gagic Laura GA Riggi Barbara Ekbom Gerard Malsher Adrien Rusch Riccardo Bommarco 《Ecology and evolution》2016,6(7):2149-2157
Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides. 相似文献
19.
An infrared spectroscopic study of the conformational transition of elastin-like polypeptides 下载免费PDF全文
The infrared spectroscopy of elastin-like polypeptides and the relation to the inverse thermal transition are discussed. To correlate the spectroscopic observations with structure a density function theory model was created that captures the essential hydrogen bonding and packing of the beta-spiral structure proposed for elastin and elastin-like polypeptides. The infrared spectrum was calculated using periodic boundary conditions and a method for estimating the difference dipole moment permits both frequencies and intensities to be obtained for the modeling of spectra. The two observed amide I bands at 1615 cm(-1) and 1656 cm(-1) are shown to arise from the beta-spiral structure. The increase in intensity of these bands with increasing salt concentration and temperature is assigned to the closer association of strands of the beta-spiral. The sharp inverse temperature transition is observed within 1 degrees C and involves a change in secondary structure that involves formation of interstrand beta-sheets for approximately 25% of the amino acids. This conclusion is consistent with available data and simulations that have been reported to date. 相似文献
20.
Journal of Insect Conservation - The first step in monitoring and management of any taxa includes resolving taxonomic ambiguities which complicate the identification of its management units. One of... 相似文献