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1.
Mansouri SM Shafiee-Nick R Parsaee H Seyedi SM Saberi MR Sadeghian H 《Iranian Biomedical Journal》2008,12(2):77-84
Background: Selective phosphodiesterase (PDE3) inhibitors improve cardiac contractility and may use in congestive heart failure. However, their proarrhythmic potential is the most important side effect. Methods: In this research, we evaluated the potential cardiotonic activity of six new synthesized selective PDE3 inhibitors (6-hydroxy-4-methylquinolin-2(1H)-one derivatives) using the spontaneously beating atria model. In each experiment, atrium of reserpine-treated rat was isolated and the contractile and chronotropic effects of a synthesized compound were assessed. The 3-isobutyl-1-methylxanthine, a non-selective PDE inhibitor, was used for comparison. Results: The results showed that, among new compounds, the best pharmacological profile was obtained with the compound 6-[4-(4-methylpiperazine-1-yl)-4-oxobutoxy]-4-methylquinolin-2(1H)-one, C6, which displayed selectivity for increasing the force of contraction (168 +/- 5% change over the control) rather than the frequency rate (138 +/- 5% change over the control) at 300 muM. However, C6 at concentrations of 10 and 100 muM produced left and upward shift in the positive inotropic concentration-response curve of isoprenaline. The -log EC50 of isoprenaline was 8.843 +/- 0.171 in the absence, 9.448 +/- 0.138 and 9.456 +/- 0.107 in the presence of 10, 100 muM of C6, respectively (P<0.001, n = 6). Also, amrinone, a selective PDE3 inhibitor, shifted the isoprenaline concentration-response curve to the left and upward. The concentration of 10 and 100 muM amrinone decreased -log EC50 of isoprenaline to 9.527 +/- 0.287 and 9.423 +/- 0.243, respectively (P<0.001, n = 6). Moreover, the positive chronotropic effect of isoprenaline was not affected by amrinone or C6. Conclusion: This study provides functional evidence for the positive inotropic effect of C6. Considering the augmentation of isoprenaline positive inotropic concentration-response with C6 and amrinone, we conclude that C6 produces its effect via potentiation of cAMP-dependent signaling system and possibly by inhibition of PDE3 activity. 相似文献
2.
Samaneh Solaymani Ahmad Ayatollahi Mehrgardi Ali Esmailizadeh Llibertat Tusell Mehdi Momen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(5):423-437
In recent years, with development and validation of different genotyping panels, several methods have been proposed to build efficient similarity matrices among individuals to be used for genomic selection. Consequently, the estimated genetic parameters from such information may deviate from their counterpart using traditional family information. In this study, we used a pedigree-based numerator relationship matrix ( A ) and three types of marker-based relationship matrices () including two identical by descent, that is and and one identical by state, as well as four Gaussian kernel () similarity kernels with different smoothing parameters to predict yet to be observed phenotypes. Also, we used different kinship matrices that are a linear combination of marker-derived IBD or IBS matrices with A, constructed as , where the weight () assigned to each source of information varied over a grid of values. A Bayesian multiple-trait Gaussian model was fitted to estimate the genetic parameters and compare the prediction accuracy in terms of predictive correlation, mean square error and unbiasedness. Results show that the estimated genetic parameters (heritability and correlations) are affected by the source of the information used to create kinship or the weight placed on the sources of genomic and pedigree information. The superiority of GK -based model depends on the smoothing parameters (θ) so that with an optimum θ value, the GK -based model statistically yielded better performance (higher predictive correlation, lowest MSE and unbiased estimates) and more stable correlations and heritability than the model with IBD, IBS or kinship matrices or any of the linear combinations. 相似文献
3.
Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah Amal Biswas 《Journal of the World Aquaculture Society》2012,43(5):679-687
The effect of five different light regimes on growth, stress and hematological indices was studied in Persian sturgeon, Acipenser persicus. Fish with average weight of 645.3 ± 11.2 g were subjected to different photoperiods (24 L, 12 L:12 D, 16 L:8 D, 8 L:16 D and 24 D) for 8 wk. Blood samples were collected at the end of the experiment for measuring cortisol, glucose and hematological features. The whole growth parameters showed no significant difference. Plasma cortisol concentration was significantly higher in 12 L:12 D, while the lowest level was observed in fish exposed to 24 D. No significant changes were observed among the treatments for glucose concentration. Lactate concentration varied significantly among the treatments. Some hematological indices including hematocrit and number of white blood cells were affected by different light regimes, but the others (hemoglobin and number of red blood cells) were not affected significantly. The results showed that photoperiod manipulation can alters some stress‐related metabolites and may enhance growth rate in fish exposing to continuous darkness. 相似文献
4.
High concentrations of manganese (Mn), iron (Fe), and aluminium (Al) induced in waterlogged acid soils are a potential constraint for growing sensitive wheat cultivars in waterlogged‐prone areas of Western Australian wheat‐belt. Tackling induced ion toxicities by a genetic approach requires a good understanding of the existing variability in ion toxicity tolerance of the current wheat germplasm. A bioassay for tolerance to high concentration of Mn in wheat was developed using Norquay (Mn‐tolerant), Columbus (Mn‐intolerant), and Cascades (moderately tolerant) as control genotypes and a range of MnCl2 concentrations (2, 250, 500, 750, 1000, 2000, and 3000 μM Mn) at pH 4.8 in a nutrient solution. Increasing solution Mn concentration decreased shoot and root dry weight and intensified the development of toxicity symptoms more in the Mn‐intolerant cv. Columbus than in Norquay and Cascades. The genotypic discrimination based on relative shoot (54% to 79%) and root dry weight (17% to 76%), the development of toxicity symptoms (scores 2 to 4) and the shoot Mn concentration (1428 to 2960 mg kg–1) was most pronounced at 750 μM Mn. Using this concentration to screen 60 Australian and 6 wheat genotypes from other sources, a wide variation in relative root dry weight (11% to 95%), relative shoot dry weight (31% to 91%), toxicity symptoms (1.5 to 4.5), and shoot Mn concentration (901 to 2695 mg kg–1) were observed. Evidence suggests that Mn tolerance has been introduced into Australian wheat through CIMMYT germplasm having “LERMO‐ROJO” within their parentage, preserved either through a co‐tolerance to Mn deficiency or a process of passive selection for Mn tolerance. Cultivars Westonia and Krichauff expressed a high level of tolerance to both Mn toxicity and deficiency, whereas Trident and Janz (reputed to be tolerant to Mn deficiency) were intolerant to Mn toxicity, suggesting that tolerance to excess and shortage of Mn are different, but not mutually exclusive traits. The co‐tolerance for Mn and Al in ET8 (an Al‐tolerant near‐isogenic line) and the absence of Mn tolerance in BH1146 (an Al‐tolerant genotype from Brazil) limits the effectiveness of these indicator genotypes to environments where only one constraint is induced. Wide variation of Mn tolerance in Australian wheat cultivars will enable breeding genotypes for the genetic solution to the Mn toxicity problem. 相似文献
5.
Waterlogging results in high shoot concentrations of iron (Fe), aluminum (Al), and manganese (Mn) in wheat grown in acidic soil. The verification of this observation in several acidic soils, development of screening techniques, and identification of genotypes differing in tolerance made it possible to test whether tolerance of ion toxicities improves performance of wheat in waterlogged acid soils. Six wheat varieties selected for tolerance/intolerance of Al, Mn, and Fe were grown in three acidic soils (pHCaCl2 4.1–4.3) with or without waterlogging for 40 d. In terms of relative shoot dry weight, Al‐, Mn‐, and Fe‐tolerant genotypes tolerated waterlogging better, outperforming intolerant genotypes by 35%, 53%, and 32%, respectively, across the soils. The Al‐tolerant genotype had up to 1.8‐fold better root growth than the intolerant genotype under waterlogging. Waterlogging increased DTPA‐extractable soil Mn (71%) and Fe (89%), and increased shoot Fe (up to 7.6‐fold) and Al (up to 5.9‐fold) for different genotypes and soils. The Al‐tolerant genotype maintained lower tissue concentrations of Al as compared to intolerant genotypes during waterlogging. Waterlogging delayed crop development but distinctly less so in the tolerant than in the intolerant genotypes, thus jeopardizing the capacity of intolerant genotypes to produce yield in Mediterranean climates with dry finish of the season. Pyramiding multiple ion tolerances into current wheat varieties with desirable agronomic and quality characteristics to enhance their performance under waterlogged acid soils should be considered. 相似文献
6.
Background: The progressive accumulation of misfolded and aggregated proteins in neurons is an accepted mechanism in aging. Overproduction of reactive oxygen species (ROS), referred to as oxidative stress, is currently believed to play a pivotal role in this process. Lipofuscin as a histological index of aging results from cross-links between oxidized proteins and lipids. Therefore, to attenuate lipofuscin formation, it would be logical to use exogenous natural or synthetic antioxidants. Yakuchinone B (1-[4''-hydroxy-3''-methoxyphenyl]-7-phenylhept-1-en-3-one) is a component of Alpinia oxyphylla seeds with established antioxidant activity. Methods: To evaluate the neuroprotective roles of yakuchinone B (JC6) and its structural analogues (JC1-JC5), the free radical scavenging capabilities of yakuchinone B derivatives were studied in terms of cell viability, apoptosis, cells ROS content, catalase (CAT) and superoxide dismutase (SOD) activity and the intracellular lipofuscin content in SK-N-MC cells exposed to H2O2. The level of MDA (malondialdehyde), as an index of lipid peroxidation and acid phosphatase activity were also measured. Results: Our results indicated that derivatives especially JC4, JC5 and JC6 decreased the extent of apoptosis and ROS level, while they increased the activities of SOD and CAT in drug-pretreated cells as compared to H2O2-treated cells. A clear relationship between the structure and antioxidant activities of these compounds was established. In addition, JC4, JC5 and JC6 were capable of down-regulating the formation of MDA and lipofuscin. Conclusion: Our results indicated that free radicals play significant roles in lipofuscin formation and cellular aging which can be attenuated by yakuchinone B derivatives.Key Words: Aging, Lipofuscin, Reactive oxygen species (ROS), Yakuchinone B 相似文献
7.
Roudgarnejad Samaneh Samdeliri Morteza Mirkalaei Amirabas Mousavi Moghaddam Mojtaba Nasheai 《Gesunde Pflanzen》2021,73(4):603-611
Gesunde Pflanzen - Humic acid comprises the major part of humic substances and the most important component of soil organic matter (humus) that increases crop yield and quality. This research aimed... 相似文献
8.
Kourosh Qaderi Vahidreza Jalali Samaneh Etminan Mojtaba Masoumi Shahr-babak Mehdi Homaee 《Paddy and Water Environment》2018,16(4):823-833
The saturated hydraulic conductivity (\(K_{\text{s}}\)) is one of the important soil hydraulic properties which plays a significant role in developing flow transport models and irrigation and drainage practices. In this research, artificial neural networks approaches, group method of data handling (GMDH) model and a hybrid intelligent model based on combination of GMDH and harmony search (HS) model (GMDH-HS) were developed to estimate \(K_{\text{s}}\) based on 151 field samples collected from the northeast of Iran. Eleven topsoil properties were used as input parameters to estimate \(K_{\text{s}}\). The five quantitative standard statistical performance evaluation measures, i.e., coefficient of efficiency, root-mean-square error, mean square relative error, mean absolute percentage error and relative bias, were employed to evaluate the performance of various developed models. Statistical results indicated that the best performance can be obtained by GMDH-HS in terms of different evaluated criteria during the training and testing datasets for \(K_{\text{s}}\) estimation. 相似文献
9.
Mahin Rafieipour Alireza Motallebi-Azar Nasser Mahna Habib Davati Kazemnia Samaneh Kazemiani Fahimeh Yarmohamadi 《Russian Agricultural Sciences》2011,37(5):385-391
In this research, the factors affecting seed production of six landraces (Sefid-e-Ghom, Germez-e-Azarshahr, Dorcheh-e-Isfahan,
Tarom, Germez-e-Kazeroon, Sefid-e-Abarkooh) and a foreign cultivar (Yellow Sweet Spanish as a control) were evaluated in a
randomized complete block design experiment with three replications. Results indicated significant differences between genotypes
regarding some of the traits. Seed stalks were emerged in Tarom and Yellow Sweet Spanish earlier than other landraces. Flowering
of Germez-e-Kazeroon and Tarom were the first and last, respectively. Also, ripening of seed in Germez-e-Kazeroon and Yellow
Sweet Spanish was earlier and later than other landraces, respectively. The number of seed stalks/plant and seed yield/ha
were increased while increasing in bulb size from 5 to 7 cm. Among the landraces, Sefid-e-Ghom and Germez-e-Azarshahr showed
the highest and lowest number of seed stalks/plant, respectively. Sefid-e-Ghom, also, showed the highest seed yield/inflorescence,
/plant and/ha. Although the differences were not significant statistically. Relationships between traits showed that seed
yield/plant and /ha was a positively correlated with the number of seed stalks/plant. Genotypes were grouped in three clusters
using Ward method. 相似文献
10.
Growth,development and behaviour of Persian sturgeon Acipenser persicus larvae in different light regimes 
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下载免费PDF全文 Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah 《Aquaculture Research》2017,48(12):5812-5820
The effects of five different light regimes on growth performance and behaviour of Persian Sturgeon larvae were examined. Larvae were reared under five different photoperiods (24L, 12L:12D, 16L:8D, 8L:16L and 24D), from hatching (25.8 ± 8.1 mg; 12 ± 0.6 mm) to 28 days post‐hatch (dph). Except the last week, there was no significant difference in growth parameters among the experimental groups. Growth performance significantly improved in larvae reared under a continuous light regime. The highest final length (34.5 ± 1.7 mm) was measured in 24L and the lowest one (29.5 ± 0.4 mm) in the constant darkness. Relative to other experimental groups, the continuous darkness had a retarding impact on the yolk sac absorption and swarming behaviour. Among the whole body compositions, the lowest body moisture content was measured in the continuous light group. Persian Sturgeon pre‐larvae and larvae were not completely dependent on light regimes (in 1–21 days), whereas on the basis of measured parameters (total length, wet and dry weight and digestive fullness index) a continuous light regime played a decisive role on growth performance beyond 21 dph. 相似文献