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Subgenus Cerasus species are useful genetic resources for cherry breeding programs. A total of 17 morphological traits together with 19 random amplified polymorphic DNA (RAPD) primers were used to study 39 accessions including 34 wild Cerasus subgenus genotypes belonging to Prunus avium L., P. cerasus L., P. mahaleb L., P. microcarpa Boiss., P. incana Pall., and P. brachypetala Boiss. species, along with an unknown wild Cerasus sample, two advanced cherry cultivars (‘Lambert’ and ‘Bulgar’), and two rootstocks (‘Colt’ and ‘Gisela 6’). Genotypes were separated into different groups according to their species and collection sites using cluster analysis performed by Ward’s clustering method based on morphological data. Nineteen RAPD primers from 60 screened produced 304 polymorphic reproducible bands (98.15% polymorphism). According to the similarity matrix, the lowest similarity was obtained between P. avium and P. microcarpa samples. A dendrogram was prepared by the unweighted pair-group method with arithmetic average (UPGMA), and the accessions were separated according to their species and geographic origin. In both morphological and molecular results, the advanced cultivars and rootstocks were separated from wild genotypes, and the unknown genotype was grouped with P. mahaleb accessions. Grouping by morphological characteristics was compared with the results of RAPD analysis, with no significant correlations between morphological and molecular data being found. This is the first report of molecular (RAPD) genetic diversity study in wild Cerasus subgenus genotypes from Iran, and the results demonstrate the high potential of RAPD analysis for discrimination of Cerasus subgenus genotypes.  相似文献   
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The water-soluble complex, [Cu(Val)(2)(NO(3))(2)]; in which Val = valacyclovir, an antiviral drug, has been synthesized and characterized by elemental analysis, furier transfer-infrared, hydrogen nuclear magnetic resonance (H NMR), and UV-Vis techniques. The binding of this Cu (II) complex to calf thymus DNA was investigated using fluorimetry, spectrophotometry, circular dichroism, and viscosimetry. In fluorimetric studies, the enthalpy and entropy of the reaction between the complex and calf-thymus DNA (CT-DNA) showed that the reaction is endothermic (ΔH = 208.22 kJ mol(-1); ΔS = 851.35 J mol(-1)K(-1)). The complex showed the absorption hyperchromism in its ultra violet-visible (UV-Vis) spectrum with DNA. The calculated binding constant, K(b), obtained from UV-Vis absorption studies was 2 × 10(5) M(-1). Moreover, the complex induced detectable changes in the circular dichroism spectrum of CT-DNA, as well as changes in its viscosity. The results suggest that this copper (II) complex interacts with CT-DNA via a groove-binding mode.  相似文献   
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The morphological variation and essential oil content of 150 individuals of motherwort (Leonurus cardiaca) from six natural regions of Iran were examined biometrically based on multivariate analysis. The highest variation was observed in plant height, length of main stems, main inflorescence length, floral cycles of main stem, lateral branches length, basal leaf length, floral leaf length width, flower length, and calyx color. Results of simple correlation analysis showed the existence of significant positive and negative correlations among some important parameters. The highest correlation was observed between plant height and length of main stems and between lateral branch length and lower surface color of leaf. Populations were clustered in two groups representing subspecies cardiaca and persicus. The subspecies cardiaca populations were closely related with each other and differentiated from the subspecies persicus by pubescence stems and leaves, more number of floral cycles, higher compaction of floral cycles, lower number of lateral branches, shorter length of petioles and leaves and smaller floral leaves. Essential oil yields varied from 0.02 (for Taleghan population) to 0.053 mg/100 g dry mater (for Kerman population). The conservation of the highly diverse native populations of Iranian motherwort germplasm is recommended.  相似文献   
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This study addresses the phylogenetic relationship between Pistacia species by amplified fragment length polymorphism (AFLP). The plant materials of this study consisted of a total of 44 accessions belonging to P. vera, P. eurycarpa, P. khinjuk, all subspecies of P. atlantica (atlantica, mutica, kurdica and cabulica), three unknown genotypes and three accessions, proposed to be hybrid from P. eurycarpa × P. atlantica. The accessions were from Iran, Turkey, USA and Syria. Six AFLP primer combinations produced a total of 475 fragments, with average of 79.16 fragments per primer pair, of which, 336 bands were polymorphic. Unweighted pair group method based on arithmetic average (UPGMA) analysis was performed on jaccard’s similarity coefficient matrix and also average similarity of each species. According to the results, two main clusters were developed and P. vera, P. eurycarpa, P. atlantica (subsp. atlantica, kurdica, mutica, cabulica) and the hybrid genotypes located in the first main cluster. P. khinjuk accessions from Iran and USA localized in second main cluster. The hybrid accessions located between eurycarpa and atlantica species and their hybrid nature between these two species were confirmed. One of the unknown accessions clustered with the hybrid ones and the two other were grouped closely with P. Khinjuk. According to this study, the closest species to P. vera was Eurycarpa group, followed by P. atlantica. UPGMA analysis separated P. atlantica subsp. mutica and cabulica from P. atlantica and P. eurycarpa. Subspecies mutica and cabulica were two closest genotypes; hence, P. atlantica subsp. mutica could be classified as a distinct species as P. mutica and the cabulica as a subspecies of P. mutica. This study revealed that P. eurycarpa is synonym for P. atlantica subsp. kurdica and should be considered distinct from P. atlantica; however, P. atlantica showed a closer genetic similarity to P. eurycarpa than the other species.  相似文献   
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ERK pathway plays a critical role in the cellular adaptive responses to environmental changes. Stressful conditions can induce the activation of activate ERK, and its downstream targets, CREB and c-fos, in neural cells. Exposure to opioids has the same effect. In this study, we investigated the effects of morphine-induced conditioned place preference (CPP) on p-ERK/ERK ratio, p-CREB/CREB ratio and c-fos level in the mesocorticolimbic dopaminergic system including the nucleus accumbens (NAc), amygdala (AMY), striatum (Str), and prefrontal cortex (PFC).Our aim was to determine if acute and subchronic stress would affect these alterations. Male Wistar rats were divided into two saline- and morphine-treated groups. Each group contained of control, acute stress, and subchronic stress subgroups. The CPP procedure was performed for all of the rats. We dissected out the NAc, AMY, Str, and PFC regions and measured the mentioned ratios and c-fos level by Western blot analysis. The results revealed that in saline-treated animals, all factors enhanced significantly after performing acute and subchronic stress while there was an exception in p-ERK/ERK ratio in the Str and PFC; the changes were not significant during acute stress. Conditioning score decreased after applying the subchronic but not acute stress. In morphine-treated animals, all factors were increased after application of acute and subchronic stress, and conditioning scores also decreased after stress. Our findings suggest that in saline- or morphine-treated animals, acute and subchronic stress increases p-ERK, p-CREB, and c-fos levels in the mesocorticolimbic system. It has been shown that morphine induces the enhancement of the mentioned factors; on the other hand, our result demonstrates that stress can amplify these changes.  相似文献   
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Glutamate receptors in mesolimbic areas such as the nucleus accumbens, ventral tegmental area, prefrontal cortex (PFC), and hippocampus (HIP) are a component of the mechanisms of drug-induced reward and can modulate the firing pattern of dopaminergic neurons in the reward system. In addition, several lines of study have indicated that cAMP response element-binding protein (CREB) and c-fos have important role in morphine-induced conditioned place preference (CPP) induced by drugs of abuse, such as morphine, cocaine, nicotine, and alcohol. Therefore, in the present study, we investigated the changes in phosphorylated CREB (p-CREB) and c-fos induction within the nucleus accumbens (NAc), HIP, and PFC after intracerebroventricular (ICV) administration of different doses of CNQX or vehicle during extinction period or reinstatement of morphine-induced CPP. In all groups, the CPP procedure was done; afterward, the conditioning scores were recorded by Ethovision software. After behavioral test recording, we dissected out the NAc, HIP, and PFC regions and measured the p-CREB/CREB ratio and c-fos level by Western blot analysis. Our results showed that administration of CNQX significantly shortened the extinction of morphine CPP. Besides, ICV microinjection of CNQX following extinction period decreased the reinstatement of morphine CPP in extinguished rats. In molecular section, in treatment group, all mentioned factors were dose-dependently decreased in comparison with vehicle group (DMSO) after ICV microinjection of different doses of CNQX but not in pre-extinction microinjection. These findings suggested that antagonism of AMPA receptor decreased p-CREB/CREB ratio and c-fos level in the PFC, NAc, and HIP. Modulation of the drug memory reconsolidation may be useful for faster extinction of drug-induced reward and attenuation of drug-seeking behavior.  相似文献   
9.
The interaction of a novel macrocyclic copper(II) complex, ([CuL(ClO4)2] that L is 1,3,6,10,12,15-hexaazatricyclo[13.3.1.16,10]eicosane) with calf thymus DNA (ct-DNA) was investigated by various physicochemical techniques and molecular docking at simulated physiological conditions (pH = 7.4). The absorption spectra of the Cu(II) complex with ct-DNA showed a marked hyperchroism with 10 nm blue shift. The intrinsic binding constant (Kb) was determined as 1.25 × 104 M?1, which is more in keeping with the groove binding with DNA. Furthermore, competitive fluorimetric studies with Hoechst33258 have shown that Cu(II) complex exhibits the ability to displace the ct-DNA-bound Hoechst33258 indicating that it binds to ct-DNA in strong competition with Hoechst33258 for the groove binding. Also, no change in the relative viscosity of ct-DNA and fluorescence intensity of ct-DNA-MB complex in the present of Cu(II) complex is another evidence to groove binding. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the binding reaction. The experimental results were in agreement with the results obtained via molecular docking study.  相似文献   
10.
Shot hole disease is one of the most important diseases of stone fruit trees in Iran. The disease is wide spread among orchards of Prunus spp. During spring and summer of 2007, 80 monoconidial isolates of the pathogen were recovered from infected leaves, fruits and twigs of different Prunus spp. in West Azerbaijan, Tehran, Ghazvin and Razavi Khorasan provinces of Iran and were studied taxonomically. Based on morphological and physiological characteristics and growth optimal temperature, all isolates were identified as Wilsonomyces carpophilus. Seedlings of stone fruits (apricot, almond, peach, nectarine, plum, sweet cherry and sour cherry) were used for pathogenicity tests. All seedlings were susceptible to the fungal isolates and showed disease symptoms on twigs, leaves, buds and petioles. Genetic diversity of 28 selected fungal isolates was investigated based on DNA fingerprinting by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), using four random primers. Based on cluster analysis of the PCR results from the four primers, 10 fingerprinting groups (clonal lineages) and 27 haplotypes were identified. Clonal lineages “C”, “D” and “E”, each with six haplotypes formed the biggest clonal lineages, but other clonal lineages (“B”, “F”, “G”, “H”, “I” and “J”) included only one isolate. No correlation was detected among clonal lineages with the location of selected isolates and their host species. A correlation was found between the substrate (fruit, twig or leaf) and clonal lineages, particularly in “C” clonal lineage. The results showed that the fungus population had high genetic diversity which is distributed among the different areas of Iran.  相似文献   
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