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1.
Plant cells often increase cold tolerance by reprogramming their genes expression which results in adjusted metabolic alternations, a process enhanced under cold acclimation (CA) phase. In present study, we assessed the changes of membrane fatty acid compositions and defense machine (like antioxidative enzymes) along with damage indexes like electrolyte leakage index (ELI) and malondialdehyde (MDA) during CA, cold stress (CS) and recovery (R) phases in chickpea (Cicer arietinum L.). Results showed an increase in unsaturated fatty acids ratio compare to saturated ones which is a sign of cold tolerance especially after CA phase. Antioxidant enzymes had an important role during CA and R phases while CS affected their activity which can be a sign for associating other metabolites or enzymes activities to create cold tolerance in plants. To investigation of enzymes assay under experimental treatments, the expression pattern of some enzymes including superoxide dismutase (sod), catalase (cat) and lipoxygenase (lox) was studied using quantitative real time PCR. LOX activity has shown a bilateral behavior: a positive relation with membrane damage index in CA and an interesting link with double bond index (DBI) in CS indicating probably its role in secondary metabolites like jasmonic acid signaling pathway. It was suggested that increased DBI and low LOX activity under CS could be a reason for plant cold tolerance.  相似文献   
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An effective chromosome doubling protocol was established in essential garden crop of cucumber (Cucumis sativus L.) Cv. Hi Power. The different concentrations of colchicine (0, 250, 500, 750, and 1500 mg/L), oryzalin (0, 5, 15, 25, 50, 75, and 150 mg/L) and trifluralin (0, 5, 15, 25, 50, 75, and 150 mg/L) were applied on parthenogenesis-induced haploid nodal and shoot tip explants of cucumber for 18 and 38 h in three independent factorial experiments. Increasing concentrations of applied antimitotic agents led to the significant reduction in the survival rate of both shoot tip and nodal explants, especially in longer exposure duration. Three ploidy levels including haploid, mixoploid, and doubled haploid were regenerated form both explant types treated with colchicine, oryzalin, and trifluralin. Flow cytometry analysis proved successful chromosome doubling of haploid plants. Based on the results obtained, the highest number of regenerated doubled haploid plants (92.31%) and fruit set (86.21%) were related to immersion of nodal explants in 50 mg/L oryzalin for 18 h. The highest doubled haploid regeneration for colchicine and trifluralin antimitotic agents were 58.33 and 83.33%, respectively. The leaf size of doubled haploid plants was larger than their correspond haploids. The optimized chromosome doubling protocol would be applicable for doubled haploid production in garden crops of Cucurbitaceae family, which is recalcitrant to the spontaneous doubling, and also for in vitro polyploidy induction studies.  相似文献   
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Salt stress imposes a major environmental threat to agriculture, therefore, understanding the basic physiology and genetics of cell under salt stress is crucial for developing any breeding strategy. In the present study, the expression profile of genes involved in ion homeostasis including salt overly sensitive (HvSOS1, HvSOS2, HvSOS3), vacuolar Na+/H+ antiporter (HvNHX1), and H+-ATPase (HVA) along with ion content measurement were investigated in two genotypes of Hordeum vulgare under 300 mM NaCl. The gene expressions were measured in the roots and shoots of a salt-tolerant mutant genotype M4-73-30 and in its wild-type cv. Zarjou by real-time qPCR technique. The critical differences between the salt-tolerant mutant and its wild-type were observed in the expressions of HvSOS1 (105-fold), HvSOS2 (24-fold), HvSOS3 (31-fold), and HVA (202-fold) genes in roots after 6-h exposure to NaCl. The parallel early up-regulation of these genes in root samples of the salt-tolerant mutant genotype indicated induction of Na+/H+ antiporters activity and Na+ exclusion into apoplast and vacuole. The earlier up-regulation of HvSOS1, HVA, and HvNHX1 genes in shoot of the wild-type genotype corresponded to the relative accumulation of Na+ which was not observed in salt-tolerant mutant genotype because of efficient inhibitory role of the root in Na+ transport to the shoot. In conclusion, the lack of similarity in gene expression patterns between the two genotypes with similar genetic background may confirm the hypothesis that mutation breeding could change the ability of salt-tolerant mutant genotype for efficient ion homeostasis via salinity oversensitivity response.  相似文献   
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International Journal of Peptide Research and Therapeutics - β-secretase 1 (BACE1) plays a pivotal role in the pathology of Alzheimer?s disease via accumulation beta amyloid in the...  相似文献   
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At present, industries within the health and life science sector are moving towards one another resulting in new industries such as the medical nutrition industry. Medical nutrition products are specific nutritional compositions for intervention in disease progression and symptom alleviation. Industry convergence, described as the blurring of boundaries between industries, plays a crucial role in the shaping of new markets and industries. Assuming that the medical nutrition industry has emerged from the convergence between the food and pharma industries, it is crucial to research how and which distinct industry domains have contributed to establish this relatively new industry. The first two stages of industry convergence (knowledge diffusion and consolidation) are measured by means of patent analysis. First, the extent of knowledge diffusion within the medical nutrition industry is graphed in a patent citation interrelations network. Subsequently the consolidation based on technological convergence is determined by means of patent co-classification. Furthermore, the medical nutrition core domain and technology interrelations are measured by means of a cross impact analysis. This study proves that the medical nutrition industry is a result of food and pharma convergence. It is therefore crucial for medical nutrition companies to effectively monitor technological developments within as well as across industry boundaries. This study further reveals that although the medical nutrition industry’s core technology domain is food, technological development is mainly driven by pharmaceutical/pharmacological technologies Additionally, the results indicate that the industry has surpassed the knowledge diffusion stage of convergence, and is currently in the consolidation phase of industry convergence. Nevertheless, while the medical nutrition can be classified as an industry in an advanced phase of convergence, one cannot predict that the pharma and food industry segments will completely converge or whether the medical industry will become an individual successful industry.  相似文献   
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The effects of irradiance and photoperiod on growth rates, chlorophyll a, β-carotene, total protein, and fatty acid content of Chlorella vulgaris were determined. The maximum growth rate (1.13 day−1) was at 100 μmol photons m−2 s−1 and 16:8-h light/dark photoperiod. Chlorophyll a and β-carotene contents significantly differed under different light regimes with chlorophyll a content lower at high irradiance and longer light duration, while β-carotene showed the inverse trend. The total protein and fatty acid content also significantly differed in different light regimes; the maximum percentage of protein (46%) was at 100 μmol photons m−2 s−1 and 16:8 h photoperiod, and minimum (33%) was at 37.5 μmol photons m−2 s−1 and 8:16 h photoperiod; the total saturated fatty acids increased, while monounsaturated and polyunsaturated fatty acids decreased with increasing irradiance and light duration.  相似文献   
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Olfactory ectomesenchymal stem cells (OE-MSCs) possess the immunosuppressive activity and regeneration capacity and hold a lot of promises for neurodegenerative disorders treatment. This study aimed to determine OE-MSCs which are able to augment and differentiate into functional neurons and regenerate the CNS and also examine whether the implantation of OE-MSCs in the pars compacta of the substantia nigra (SNpc) can improve Parkinson's symptoms in a rat model-induced with 6-hydroxydopamine. We isolated OE-MSCs from lamina propria in olfactory mucosa and characterized them using flow cytometry and immunocytochemistry. The therapeutic potential of OE-MSCs was evaluated by the transplantation of isolated cells using a rat model of acute SN injury as a Parkinson's disease. Significant behavioral improvement in Parkinsonian rats was elicited by the OE-MSCs. The results demonstrate that the expression of PAX2, PAX5, PITX3, dopamine transporter, and tyrosine hydroxylase was increased by OE-MSCs compared to the control group which is analyzed with real-time polymerase chain reaction technique and immunohistochemical staining. In the outcome, the transplantation of 1,1′-dioctadecyl-3,3,3′3'-tetramethyl indocarbocyanine perchlorate labeled OE-MSCs that were fully differentiated to dopaminergic neurons contribute to a substantial improvement in patients with Parkinson's. Together, our results provide that using OE-MSCs in neurodegenerative disorders might lead to better neural regeneration.  相似文献   
9.
To investigate key regulatory components and genes with great impact on salt tolerance, near isogenic or mutant lines with distinct salinity tolerance are suitable genetic materials to simplify and dissect the complex genes networks. In this study, we evaluated responses of a barley mutant genotype (73-M4-30), in comparison with its wild-type background (Zarjou) under salt stress. Although the root growth of both genotypes was significantly decreased by exposure to sodium chloride (NaCl), the effect was greater in the wild type. The chlorophyll content decreased under salt stress for the wild type, but no change occurred in the mutant. The mutant maintained the steady-state level of [K+] and significantly lower [Na+] concentrations in roots and higher [K+]/[Na+] ratio in shoots under salt conditions. The catalase (CAT), peroxidase (POD) activity, and proline content were higher in the mutant than those in the wild type under controlled conditions. The soluble proline was higher after 24 h of salt stress in roots of the mutant but was higher after 96 h of salt stress in the wild type. The CAT and POD activity of the mutant increased under salt stress which was as a coincidence to lower levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents. The ratio of dry-to-fresh weight of the roots increased for the mutant under salt stress which was as a result of the higher phenylalanine ammonia-lyase (PAL) gene expression and peroxidase activity and involved in cell wall lignification. Consequently, it seems that ion homeostasis and increased peroxidase activity have led to salt tolerance in the mutant’s genotype.  相似文献   
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Venom from the sea anemone, Heteractis magnifica, has multiple biological effects including, cytotoxic, cytolytic and hemolytic activities. In this study, cytotoxicity induced by H. magnifica venom was investigated using the crystal violet assay on human breast cancer T47D and MCF7 cell lines and normal human breast 184B5 cell line. Apoptosis was also assayed via Annexin V-flourescein isothiocyanate and propidium iodide (PI) staining followed by flow cytometric analysis. Cell cycle progression and mitochondria membrane potential were studied via flow cytometry following PI and JC-1 staining respectively. H. magnifica venom induced significant reductions in viable cell numbers and increases in apoptosis in T47D and MCF7 in dose-dependent manners. A significant apoptosis-related increase in the sub G1 peak of the cell cycle in both breast cancer cell lines was also observed. Moreover, treatment by venom cleaved caspase-8, caspase-9, and activated caspase-3. Overall, H. magnifica venom was highly cytotoxic to T47D and MCF7 human breast cancer cells, and the phenomenon could be the killing phenomenon via the death receptor-mediated and the mitochondria-mediated apoptotic pathways. Consequently, H. magnifica venom has potential for the development of a breast cancer therapeutic.  相似文献   
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