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41.
Background: Friedreich ataxia (FRDA) is an autosomal recessive disorder caused by guanine-adenine-adenine (GAA) triplet expansions in the FXN gene. Its product, frataxin, which severely reduces in FRDA patients, leads to oxidative damage in mitochondria. The purpose of this study was to evaluate the triple nucleotide repeated expansions in Iranian FRDA patients and to elucidate distinguishable FRDA clinical differences in these patients. Methods: A number of 22 Iranian patients (8 females and 14 males) from 16 unrelated families were studied. DNA was extracted from the peripheral blood of patients. The frequency and length of (GAA)n repeats in intron 1 of the FXN gene were analyzed using long-range PCR. In this study, the clinical criteria of FRDA in our patients and the variability in their clinical signs were also demonstrated. Results: An inverse relationship was observed between GAA repeat size and the age of onset. Although some distinguishable clinical features (such as limb ataxia and lower limb areflexia) were found in our patients, 90-95% of them had extensor plantar response and dysarthria. The results showed only one positive diabetes patient and also different effects on eye movement abnormality among our patients. Conclusion: The onset age of symptoms showed a significant inverse correlation with allele size in our patients (P>0.05). Based on comparisons of the clinical data of all patients, clinical presentation of FRDA in Iranian patients did not differ significantly from other FRDA patients previously reported. Key Words: Friedreich ataxia (FRDA), Frataxin, Mitochondria  相似文献   
42.
Understanding the genetic factors governing developmental patterns and flowering time in breeding materials is required for the development of new wheat varieties for a specific environment. Iran is among the largest wheat producers in the arid and semi-arid regions of the Middle East and North Africa. The wheat germplasm grown in Iran is either developed nationally or is introduced from the CIMMYT global wheat program. For decades, the wheat breeding program in Iran focused on generating new varieties better able to grow in the predominant Iranian climatic conditions such as humidity at the reproductive stage, high temperature during reproductive stages (terminal heat stress), moderate temperature during the cropping season, and high probability of frost damage during early stages of growth. There have also been sub-programs aimed at developing drought and salinity-tolerant wheat cultivars in Iran. Knowledge of cultivars’ growth habits in Iran is currently limited to flowering in spring-sown nurseries. We identified allelic diversity in loci involved in vernalization response (Vrn) and photoperiod sensitivity (Ppd) in 60 bread wheat cultivars developed in Iran, CIMMYT, or ICARDA. This study revealed that the spring growth habit observed in most of the cultivars is conferred by a combination of recessive vrn-A1 and dominant Vrn-D1, Vrn-B1, and/or Vrn-B3 loci. This implies that most of the cultivars have minimal vernalization requirements for overwintering. Perhaps cold winters, even in the southern regions of Iran, provide sufficient vernalization conditions for cultivars possessing the recessive vrn-A1 allele. The germplasm investigated in this study revealed no evidence indicating selection for or against any specific Vrn and Ppd allele in our wheat breeding program.  相似文献   
43.
Hairy vetch (Vicia villosa) is an important cover crop and green manure in dryland cropping system of Mediterranean regions. A delay in the onset of rainfall during autumn can inhibit hairy vetch seed germination, which exposes its early growth stages to low-temperature stress. The present study was carried out in a completely randomized design with four replications to evaluate the effects of seed priming on germination of hairy vetch under chilling stress. The treatments were seed-priming type (unprimed, hydro-priming, halo-priming, and osmopriming) and temperature (3, 6, 9, 12, and 15?°C). The results indicated that a decrease in temperature produced a linear decline in the germination rate of seeds treated with halo-priming and osmopriming (p?<?.01). The seedling length, seedling dry weight, and vigor index decreased in plants experiencing chilling stress (quadratic; p?<?.01) for hydro-priming, halo-priming, and osmopriming. The maximum germination rate was achieved using hydro-priming. Osmopriming prevented a decrease in the rate of germination at 3?°C. A decrease in temperature increased the proline and the soluble protein contents in all the seed priming treatments, but, decreased catalase and guaiacol peroxidase activity (p?<?.01). In brief, halo-priming, and hydro-priming enhanced establishment and growth of hairy vetch under chilling stress primarily through improvements in the physiological parameters and germination rate. This finding can increase the potential for cultivation of the hairy vetch in late planting date.  相似文献   
44.
The importance of knowledge sharing, as an integral part of decision making, has been highly acknowledged by many authors. However, the process in which knowledge sharing should be conducted has remained a debatable issue. In this study, changes in experts’ attitudes, as a result of the knowledge-sharing process, in the context of rangeland management were assessed. We demonstrated a three-step knowledge-sharing process while recognizing collaborative knowledge sharing systems, which involves knowledge-sharing tools including face-to-face and virtual approaches. The process was applied to explore experts’ attitudes regarding livelihood alternatives in the Bazoft region of southwestern Iran. Sixty experts were selected from three groups categorized as key local stakeholders, practitioners, and scientists. First, the experts were independently given the task of ranking livelihood alternatives. Next, for a better understanding of alternatives and enhancing their view, additional knowledge and information were provided. Thereafter, their attitudes in the final step were assessed. According to the findings, change in the experts’ attitudes could take place, which eventually resulted in the prioritization of livelihood alternatives to approach sustainable rangeland management (SRM). The synergy of experts’ knowledge, which can be realized through a collaborative knowledge sharing process, can be further pursued by devising a workable policy framework to approach SRM.  相似文献   
45.
A 20-week growth trial was conducted to investigate the effect of two dietary blended vegetable oils (VO) on liver lipogenic enzyme activity, liver and gonad lipid class composition and fatty acid profiles, serum sex hormones, and gonad morphohistology in gilthead seabream, Sparus aurata. Three groups of fish (BW i 130.9 ± 3.1 g) were fed, close to satiation, three experimental diets: a control (CTRL) contained fish oil (FO) as the sole lipid source (100% FO) and two VO-blended diets in each 60% of FO was substituted by an equal mixture of cottonseed oil (CO), sunflower oil (SFO) and either linseed oil (LO) or soybean oil (SBO), designated as LO or SBO diet, respectively. Each diet was assigned to triplicate groups of fish. Results showed that all dietary treatments presented no significant (P > 0.05) differences in growth rate and feed conversion ratio for sexes combined. Enzyme activities of liver lipogenic enzymes of LO-fed fish (glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme (ME) and fatty acid synthetase (FAS)) were not statistically (P > 0.05) different from those of CTRL fish. Only in the group of fish fed the SBO diet, G6PDH was slightly higher (P < 0.05) for both sexes, while ME showed a significant (P < 0.05) higher activity only in females relative to CTRL fish. Liver FAS enzyme activity remained unaltered among dietary groups. VO-fed fish recorded a significant (P < 0.05) increase in total lipid (TL) and triglyceride (TAG) contents in both liver and gonad, more pronounced in females than in males, concurrent with a significant (P < 0.05) decrease in cholesterol (CHL) and phospholipids (PL), more obvious for the SBO-fed fish, as compared to CTRL. The fatty acid (FA) composition of liver or gonad reflected that of the supplied diet and evidenced a significant (P < 0.01 or <0.05) alteration in the majority of individual FA in VO-fed fish compared to CTRL. There were decreased levels of ARA (20:4 n-6), EPA (20:5 n-3), and DHA (22:6 n-3) in VO-fed fish, more pronounced in females than in males, compared to CTRL. The liver and gonad FA profiles, for males and females, reflected the composition of the diet and showed sex variation in the output of multivariate principal component analysis (PCA). Feeding fish VO diets has also led to a significant (P < 0.05) reduction in serum estradiol level by 15.8 or 22.3% in LO- or SBO-fed fish, respectively, and in testosterone level by 7.7% in the latter dietary group only compared to the CTRL. Histomorphological examination of ovary and testis has indicated a relative retardation in oogenesis and spermatogenesis in VO-fed fish, less obvious in the LO-fed fish compared to CTRL. These results suggest a preference of LO over SBO blend diet in terms of liver lipogenic enzyme activity, liver and gonad lipid content, lipid class composition and fatty acid profile, serum sex hormones as well as gonad maturation. PCA analysis of gonads highlighted the importance of using a 100% marine FO diet for gilthead seabream broodstock for the recovery of a normal FA profile in gonads of fish, previously fed VO over the production cycle, to ensure successful spawning.  相似文献   
46.
Background: Wound healing of burned skin remains a major goal in public health. Previous reports showed that the bone marrow stem cells were potent in keratinization and vascularization of full thickness skin wounds. Methods: In this study, mesenchymal stem cells were derived from rat adipose tissues and characterized by flowcytometry. Staining methods were used to evaluate their differentiation ability. A collagen-chitosan scaffold was prepared by freeze-drying method and crosslinked by carbodiimide-based crosslinker. Results: The results of immunecytochemistry and PCR experiments confirmed the adipose-derived stem cells (ASC) in differentiation to the keratinocytes under the treatment of keratinocyte growth factor. The isolated ASC were seeded on the scaffolds and implanted at the prepared wounds. The scaffolds without cells were considered as a control and implanted on the other side of the rat. Histopathological analyses confirmed the formation of new tissue on the scaffold-cell side after 14 days with the formation of dermis and epidermis. Conclusion: These results indicated the capacity of ASC in differentiation to keratinocytes and also wound healing in vivo. Key Words: Tissue engineering, Keratinocytes, Mesenchymal stem cells  相似文献   
47.
Background: The aim of this research was to study the distribution and changes of glycoconjugates particularly their terminal sugars by using lectin histochemistry during mouse spinal cord development. Methods: Formalin-fixed sections of mouse embryo (10-16 fetal days) were processed for lectin histochemical method. In this study, two groups of horseradish peroxidase-labeled specific lectins were used: N-acetylgalactosamine, including Dolichos biflorus, Wisteria floribunda agglutinin (WFA), Vicia villosa, Glycine max as well as focuse-binding lectins, including tetragonolobus, Ulex europaeus, and Orange peel fungus (OFA). All sections were counterstained with alcian blue (pH 2.5). Results: Our results showed that only WFA and OFA reacted strongly with the floor plate cells from early to late embryonic period of developing spinal cord. The strongest reactions were related to the 14, 15, and 16 days of tissue sections incubated with OFA and WFA lectins. Conclusion: The present study demonstrated that cellular and molecular differentiation of the spinal cord organizers is a wholly regulated process, and α-L-fucose, α-D-GalNAc, and α/β-D-GalNAc terminal sugars play a significant role during the prenatal spinal cord development.Key Words: Development, Glycoconjugates, Spinal cord  相似文献   
48.
Stemphylium lycopersici (Enjoji) W. Yamam was initially described from tomato and has been reported to infect different hosts worldwide. Sequence analyses of the internal transcribed spacer (ITS) regions 1 and 2, including 5.8S rDNA (ITS-5.8S rDNA) and glyceraldehyde-3-phosphate dehydrogenase (gpd) gene, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), as well as virulence studies were conducted to analyze 46?S. lycopersici isolates. Stemphylium lycopersici isolates used in this study were obtained from diseased tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), pepper (Capsicum annuum L.) and lettuce (Lactuca sativa L.) from major vegetable growing regions of Malaysia, including the three states of Pahang, Johor and Selangor between 2011 and 2012. Phylogenetic analysis of a combined dataset of the ITS-5.8S rDNA and gpd regions indicated that all isolates were clustered in the sub-cluster that comprised S. lycopersici, and were distinguished from other Stemphylium species. Cluster analyses using the UPGMA method for both RAPD and ISSR markers grouped S. lycopersici isolates into three main clusters with similarity index values of 67 and 68 %. The genetic diversity data confirmed that isolates of S. lycopersici are in concordance to host plants, and not geographical origin of the isolates. All S. lycopersici isolates were pathogenic on their original host plants and showed leaf spot symptoms; however, virulence variability was observed among the isolates. In cross-inoculation assays, the representative isolates were able to cause leaf spot symptoms on eggplant, pepper, lettuce and tomato, but not on cabbage.  相似文献   
49.
Native grasses are excellent candidate species for manipulation to produce dwarf and turf type varieties as well as for producing cultivars with higher attractiveness and requiring less maintenance to be used as a turf grass in arid and semi-arid regions of the world. This investigation was conducted to explore visual qualities of native grasses and their mixtures compared to commercial turf. The field experiment was set out in a split-plot in time based on a randomized experimental design with three replications. We used two native monoculture accessions, perennial ryegrass (Lolium perenne L. ‘Yarand’) and (Lolium perenne L. ‘Shadegan’), Native low-variety Mixture (NM1): consisting of 50% Lolium multiflorum ‘Shadegan’? 50% Festuca spp. ‘Shadegan’, Native high-variety Mixture (NM2): consisting of 55% Lolium perenne L. ‘Yarand’? 35% Lolium perenne L. ‘Shadegan’? 5% L. multiflorum ‘Shadegan’ and 5% Festuca spp. ‘Shadegan’ and compared this with one commercial turf mixture that is commonly used in landscaping. Results indicated the effects of seasons and turf grass types and their interaction had significant effects on most variables including quality, season color, leaf texture, density, quality after clipping (p < 0.01). The visual quality measurements indicated the superiority of L. perenne ‘Shadegan’ over other native monoculture and polyculture and its ablility to compete with the commercial turf. The native turf mixture of NM2 showed several good characteristics. L. perenne ‘Yarand’ had statistically the lowest score for visual appeal as compared with the other turf types. This research suggests that the use of native grass species of L. perenne ‘Shadegan’ is worth investigating for better performance of the native landscape.  相似文献   
50.
Using plant extracts as immunostimulants in aquaculture has prove effectiv in resisting infectious disease, in addition to being safe and inexpensive. The present study is concerned about the prospective mode of action of using lesser galangal extract (Alpinia officinarum) encapsulated into amine surface functionalized mesoporous silica nanoparticles (MSN) in order to elevate the immune status of rainbow trout (Oncorhynchus mykiss). Fish were randomly divided into 6 groups and fed for 4 weeks with commercial diets supplemented with 0% (control), 0.5% and 1.5% of lesser galangal extract, and with previous concentrations encapsulated with MSN (0.5% + MSN, 1.5% + MSN) and MSN (without extract). The effects of the feeding trial on the innate humoural immune parameters (total protein, myeloperoxidase content, lysozyme antiproteases and bactericidal activities) in rainbow trout were examined. Also, the influence of dietary supplement on some immune‐related genes in rainbow trout head kidney (TNF, IL‐8, IL‐1b, LYZ2 and CD4) after challenge with Yersinia ruckeri was examined. The results revealed enhancement in immune parameters in all treatment groups compared to the control, especially in the fish group fed with 1.5% + MSN which showed the highest significant difference (p < .05) in total protein, lysozyme and antiproteases activities. Also, feeding lesser galangal extract encapsulated into MSN led to an increase in myeloperoxidase content and bactericidal activity. An improvement in the expression of immune‐related genes has been recorded in fish groups fed doses of lesser galangal extract and lesser galangal extract encapsulated into MSN compared to the control or to the group fed with MSN only. Particularly, the group fed with 0.5% + MSN showed a significant up‐regulation in most of the immune‐related genes. The current investigation supports using lesser galangal extract encapsulated into MSN in fish diets as a supplement to enhance the immune response of rainbow trout and elevate its resistance to infectious diseases.  相似文献   
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