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One of the most common strategies in the treatment of cognitive disorders is enhancing the acetylcholine level in the brain through the inhibition of acetylcholinesterase. Despite the effectiveness of current modern drugs, more attention has been paid for finding new anticholinesterase agents from medicinal plants. Zatraia multiflora Boiss. is an endemic plant to Iran which has different uses in traditional medicine as anti-inflammatory, antimicrobial, anti spasmodic. We intended to evaluate the in vitro anticholinesterase and free radical scavenging activity of the essential oil and methanolic extract of Z. multiflora. The essential oil and methanolic extract of the plant were evaluated for anticholinesterase activity using modified Ellman method. The free radical scavenging effect of the samples were studied by using of the diphenylpicrylhydrazyl (DPPH). IC50 and the percent of inhibition of acetylcholinesterase was calculated from regression equation. The results showed that both the essential oil and methanolic extract of the plant exhibited high anticholinesterase activity (95.3 +/- 3.4 and 87.9 +/- 2.2% inhibition, respectively) which was similar to eserine (96.2 +/- 1.7% inhibition). The IC50 value of essential oil was determined as 0.97 +/- 0.12 microg mL(-1) in comparison to eserine (0.13 +/- 0.02 microg mL(-1)). The results of antioxidant assay showed that both the essential oil and methanolic extract potentially inhibit DPPH free radical (94.8 +/- 2.4 and 93.2 +/- 1.7% inhibition, respectively). The essential oil and methanolic extract of Z. multiflora have beneficial effect in health promotion and this plant would be good candidate for further studies.  相似文献   
23.
An experiment was conducted to investigate the effects of calcium and nitrogen on quality and quantity of Rosa hybrida in hydroponic culture, using factorial complete randomized design with different levels of ammonium-N (0, 2.5, and 5 mM) and calcium (1.6 and 4.8 mM). The results indicated that ammonium-N concentration of 2 mM increased the number of flowers, length of pedicles, and fresh weight of flower stem per plant. 5 mM of ammonium-N caused a significant decrease in most of the measured characteristics. Increase in calcium concentration enhanced nitrogen, calcium, manganese, and boron; while, potassium, zinc, and copper decreased in the leaf. Flower diameter and fresh weight of flower stems per plant increased significantly. With application of ammonium in the nutrient solution, calcium and potassium concentration in the leaf decreased, whereas phosphorus, zinc, manganese, iron, and boron significantly increased. Therefore, application of 2.5 mM ammonium-N and 4.8 mM calcium are recommended.  相似文献   
24.
Pyrus L. is a taxonomically difficult genus mainly because of interspecific and intergeneric hybridization. A majority of the wild species of Pyrus occurs in Iran, making this region very important for any study of the systematics of the genus. In this investigation, seven quantitative and seven qualitative characters of leaf epidermis, particularly epidermal cells shape, anticlinal walls patterns, type and size of stomata, and cuticular ornamentation of 22 taxa of Pyrus plus Malus orientalis are studied for assessment of their taxonomical value at different levels. Scanning electron microscopy and light microscopy were used for evaluation of epidermis features of these taxa. Some characters such as shape and anticlinal wall pattern of epidermal cells, presence of adaxial stomata, pattern of cuticular ornamentation and epicuticular wax types are useful in separation of some Pyrus taxa. Moreover, Malus orientalis is recognized easily from all Pyrus species via the density of stomata. According to ANOVA analysis, all quantitative variables show high level of between-group differentiation. Also, based on the hierarchical clustering results gained by multiple correspondence analysis and factor analysis of mixed data analyses of the current study, micromorphological characters of epidermal cells reflect the ecological conditions of pear taxa, so most of the mesophyte and xerophyte taxa can be separated from each other in accordance with epidermal cells characters, specially the anticlinal wall pattern. Totally, the application of some other biological markers, particularly suitable molecular data are needed to present well-resolved relationships among these taxa.  相似文献   
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Knowledge of relationships among the cultivated and wild species of Cerasus, a subgenus of Prunus L., is important for recognizing gene pools, identifying pitfalls in germplasm collections and developing effective conservation and management strategies. In this study, morphological characterization of wild Cerasus subgenus species naturally growing in Iran, including P. avium L. (mazzard), P. mahaleb L., P. brachypetala Boiss., P. incana Pall., P. yazdiana Mozaff., P. microcarpa Boiss. subsp. microcarpa, P. microcarpa Boiss. subsp. diffusa and P. pseudoprostrata Pojark. and three commercial species, sweet cherry (P. avium L.), sour cherry (P. cerasus L.) and duke cherry (P. × gondouinii Rehd.) was investigated. Twenty-nine variables were recorded in 95 accessions of these species to detect similarities among them. All studied characteristics were showing a high degree of variability, but it was highly pronounced for plant height, leaf characters especially for dimensions and pubescence as well as for petiole and peduncle length. The majority of significant correlation coefficients were found in the characteristics representing plant size and growth habit with leaf size. Principal component analysis was performed for phenotypical diversity determination and grouping of species. Characters with high discriminating values were those related to growth habit, height, compactness, trunk diameter, leaf dimensions, petiole length, leaf tip and serration, flower color, peduncle length, fruit shape and stone shape. Based on the cluster analysis, species included in two main clusters, first those with large structure (sweet, sour and duke cherries, mazzard and mahaleb), second the other species with small structure which might be potentially suitable for rootstock breeding programs. Scatter plot using two first factors also confirmed the grouping by cluster analysis. The conservation of the highly diverse native populations of Iranian wild Cerasus species is recommended.  相似文献   
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ABSTRACT We have been working on proteins that are involved in the defense response of western white pine (WWP) (Pinus monitcola) to the blister rust fungus Cronartium ribicola. Our objective was to identify candidate genes that could be used for improving resistance of WWP to this rust pathogen. During proteomic analysis of bark proteins extracted from WWP trees exhibiting slow-canker-growth (SCG) resistance, a 10.6-kDa peptide, termed Pm-AMP1, was found to be enriched at the receding canker margin. The cDNA encoding this peptide was cloned and characterized. A BLASTX search revealed that the Pm-AMP1 encoded by its cDNA has a 50% homology with MiAMP1, a broad-spectrum antifungal protein isolated from Macadamia integrifolia. Based on the deduced amino acid sequence, an antibody was produced against the Pm-AMP1. Immunochemical quantification of the Pm-AMP1 in bark samples of susceptible WWP trees revealed this protein to be barely detectable in the cankered tissues, but occurring in higher concentrations in healthy tissues away from canker margins. Foliage of SCG-resistant trees contained higher concentrations of the Pm-AMP1 than foliage from susceptible cankered trees. Both wounding and methyl jasmonate treatment of WWP needles induced the expression of this protein, further supporting its putative role as a defense response protein.  相似文献   
28.
The effect of colchicine added to induction medium for the production of fertile doubled haploid plants after in‐vitro anther culture was studied in wheat, Triticum aestivum L. For this, one winter and two spring wheat varieties were used. Anther cultures of the three genotypes were treated with 0.03% colchicine for 3 days at the beginning of microspore induction. Colchicine had no significant effect on anther response and embryoid production of the genotypes examined. However, in the winter wheat genotype ‘Mv Szigma’, colchicine caused a significant reduction in microspore‐derived structures. A significant decrease was also observed in plant regeneration ability of two genotypes (‘Vergina’ and ‘Acheloos’) after colchicine treatment. In addition, a significant reduction of the albinos produced was observed in all genotypes after olchicine treatment. In contrast, the regenerants obtained from the colchicine‐supplemented induction media produced significantly higher percentages of fertile plants in all genotypes. However, the level of fertility, was significantly different among the fertile plants obtained. This, together with the observation that in the case of the winter wheat variety the colchicine treatment resulted in 100% completely fertile plants with a high seed‐setting ability indicate that there is space for further improvement of the method when it is applied to spring cultivars. Finally, the increased number of seeds per 100 plated anthers obtained from all three genotypes after colchicine treatment, clearly demonstrates that the addition of colchicine to induction medium was superior to the conventional anther culture method and it could therefore be introduced into wheat breeding programmes.  相似文献   
29.
Background:Glioblastoma is the most common primary malignant neoplasm of the central nervous system. Despite progress in diagnosis and treatment, glioblastoma still has a poor prognosis. This study aimed to examine whether a signature of three candidate miRNAs (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) can be used as a diagnostic biomarker for distinguishing glioblastoma from healthy brain tissues. Methods:In this study, 50 FFPE glioblastoma tissue samples and 50 healthy tissue samples adjacent to tumor were included. The expression of each candidate miRNA (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) was measured using RT-qPCR. To show the roles of each miRNA and their biological effects on glioblastoma development and clinicopathological characteristics, in silico tools were used. ROC curves were performed to assess the diagnostic accuracy of each miRNA. Results:Based on the results, hsa-let-7c-5p and hsa-miR-206-5p were downregulated, while hsa-miR-1909-5p was upregulated in glioblastoma tumors compared to healthy samples. No association was detected between the expression of each candidate miRNA and sex. Except for hsa-let-7c-5p, other miRNAs did not correlate with age status. ROC curve analysis indicated that the signature of candidate miRNAs is a potential biomarker distinguishing between glioblastoma and healthy samples. Only hsa-miR-206-5p suggested the association with poor prognosis in glioblastoma patients. Conclusion:Our findings revealed that the signature of three miRNAs is capable of distinguishing glioblastoma tumor and healthy tissues. These results are beneficial for the clinical management of glioblastoma patients.Key Words: Inflammation, Gastric cancer, Gene expression, Pattern recognition receptors, RNA-seq  相似文献   
30.
1. Gelatin prepared from calf bones (GCB) is a novel source of high-quality protein and phosphorus. Its inclusion in broiler chicken diets may improve bone strength, plasma and digestive alkaline phosphatase activity (ALP), phosphorus digestibility and performance of broilers. Therefore, di-calcium phosphate in a corn-soy control diet was replaced with 12, 24, and 36 g/kg of GCB in a completely randomised design with four treatments of six replicates and 10 chicks in each pen. The trial lasted from 1 to 42 d of age.

2. Body weight and feed intake were measured weekly. Plasma calcium and phosphorus concentration along with plasma and digestive ALP were assayed throughout the trial. Trypsin, α-amylase, lipase and total protease activity were assayed at 14 and 28 d of age. Tibia ash, calcium and phosphorus content and breaking strength were measured at 14, 28 and 42 d of age. Phosphorus digestibility was measured at 36 d of age.

3. Body weight and feed intake showed no significant differences between controls and diets containing 12 and 36 g/kg GCB. Tibia ash and tibia length were increased by supplementation of GCB (P ≤ 0.001). Tibia calcium and phosphorus content were increased by GCB inclusion at 14 d of age (P ≤ 0.001). Digestive alkaline phosphatase activity was increased and trypsin activity was reduced by inclusion of GCB (P ≤ 0.001; P ≤ 0.004). α-amylase activity decreased by inclusion of 12 and 24 g/kg GCB, whereas an increase in α-amylase activity was observed by inclusion of 36 g/kg GCB (P ≤ 0.001). Supplementation of diets with GCB increased phosphorus digestibility (P ≤ 0.01) and suppressed ileum growth during the experimental period.

4. Results of the current study showed that phosphorus from gelatin can greatly improve broiler bone characteristics and phosphorus digestibility and complete elimination of inorganic phosphate sources from broiler diets is feasible with inclusion of 36 g/kg high phosphorus gelatin.  相似文献   

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