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21.
Fahimeh Alizadeh Siti Nor Akmar Abdullah Pei Pei Chong Ahmad Bin Selamat 《Plant Molecular Biology Reporter》2014,32(1):70-81
The fatty acid (FA) signaling pathway is emerging as an important mechanism in plant responses during interactions with microbial organisms. For a comprehensive evaluation of key FA biosynthetic pathway genes during interactions of oil palm (Elaeis guineensis Jacq.) with the pathogenic Ganoderma boninense and symbiotic Trichoderma harzianum fungal organisms, a lane-based array analysis of gene expression in artificially inoculated oil palm seedlings was performed. The results obtained demonstrated that acetyl-CoA carboxylase (ACC), β-ketoacyl-ACP synthases (KAS) II and III, palmitoyl-ACP thioesterase (PTE), oleoyl-ACP thioesterase (OTE) and glycerol-3-phosphate acyltransferase (ACT) showed identical responses in root and leaf tissues for the same fungi. The expression of these genes was up-regulated in both root and leaf tissues at 21 days post-inoculation (dpi) during interaction of oil palm with G. boninense. Thereafter, production of physical symptoms occurred at 42 and 63 dpi concomitantly with suppression of expression of these genes. An increase in the expression level of these genes was observed in both tissues at 3–63 dpi, which correlated with the colonization of roots and promotion of plant growth by T. harzianum. These data suggest that FA biosynthetic pathway genes are involved in the defense response of oil palm to infection. Identical plant responses by FA biosynthetic pathway genes may lead to enhanced resistance against G. boninense and could be a useful marker to contribute towards early detection of infection. The distinct expression profile during symbiotic interaction demonstrated its role in plant resistance mechanisms and growth promotion by T. harzianum. 相似文献
22.
Usefulness of rpoB Gene Sequencing for Identification of Afipia and Bosea Species, Including a Strategy for Choosing Discriminative Partial Sequences 下载免费PDF全文
Atieh Khamis Philippe Colson Didier Raoult Bernard La Scola 《Applied microbiology》2003,69(11):6740-6749
Bacteria belonging to the genera Afipia and Bosea are amoeba-resisting bacteria that have been recently reported to colonize hospital water supplies and are suspected of being responsible for intensive care unit-acquired pneumonia. Identification of these bacteria is now based on determination of the 16S ribosomal DNA sequence. However, the 16S rRNA gene is not polymorphic enough to ensure discrimination of species defined by DNA-DNA relatedness. The complete rpoB sequences of 20 strains were first determined by both PCR and genome walking methods. The percentage of homology between different species ranged from 83 to 97% and was in all cases lower than that observed with the 16S rRNA gene; this was true even for species that differed in only one position. The taxonomy of Bosea and Afipia is discussed in light of these results. For strain identification that does not require the complete rpoB sequence (4,113 to 4,137 bp), we propose a simple computerized method that allows determination of nucleotide positions of high variability in the sequence that are bordered by conserved sequences and that could be useful for design of universal primers. A fragment of 740 to 752 bp that contained the most highly variable area (positions 408 to 420) was amplified and sequenced with these universal primers for 47 strains. The variability of this sequence allowed identification of all strains and correlated well with results of DNA-DNA relatedness. In the future, this method could be also used for the determination of variability “hot spots” in sets of housekeeping genes, not only for identification purposes but also for increasing the discriminatory power of sequence typing techniques such as multilocus sequence typing. 相似文献
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24.
Abbas Azadmehr Keyvan Alizadeh Oghyanous Reza Hajiaghaee Zahra Amirghofran Mohammad Azadbakht 《Cellular and molecular neurobiology》2013,33(8):1135-1141
In this study, the neuroprotective effect of Scrophularia striata Boiss (Scrophulariaceae) extract, a plant growing in northeastern of Iran, against oxidative stress-induced neurocytotoxicity in PC12 was evaluated. The PC12 cell line pretreated with different concentrations (10, 50, 100, and 200 μg/ml) of the extract and then treated with H2O2 to induce oxidative stress and neurotoxicity. Survival of the cells, reactive oxygen species (ROS) generation, and apoptosis were measured using MTT assay, fluorescent probe 2′,7′-dichlorofluorescein diacetate, and annexin V/propidium iodide, respectively. Moreover, the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) was used to evaluate the antioxidant capacity of the plant extract. Phytochemical assay by thin layer chromatography showed that the main components, including phenolic compounds, phenyl propanoids and flavonoids, were presented in the S. striata extract. The extract in concentrations of 50–200 μg/ml protected PC12 cells from H2O2-induced toxicity. The survival of the cells at concentration of 200 μg/ml was 64 % compared to that of H2O2 alone-treated cells (48 %) (p < 0.001). The extract also dose-dependently reduced intracellular ROS production (p < 0.001). Moreover, the extract showed antioxidative effects and decreased apoptotic cells. Collectively, these findings indicated the ability of S. striata to decrease ROS generation and cell apoptosis and also suggest the presence of the neuroprotective agents in this plant. 相似文献
25.
Shohreh Fahimirad Seyed Hadi Razavi Hamid Abtahi Houshang Alizadeh Mansour Ghorbanpour 《International journal of peptide research and therapeutics》2018,24(1):213-222
There is a growing research interest on products with antimicrobial activity. Antimicrobial polymers are one of the most surefire procedures to combat microbes. In the present study, the ability of Βeta-casein- one of the milk major self assembly proteins with high polymeric film production capability—as a fusion partner of Ib-AMP4 antimicrobial peptide was investigated. Also, the antimicrobial activities of Βeta-casein- IbAMP4 fusion protein antimicrobial against common food pathogens were assessed. The pET21a-BCN-Ib-AMP 4 construct was transformed to Escherichia coli BL21 (DE3), and protein expression was induced under optimized conditions. Purified protein obtained from nickel affinity chromatography was refolded under optimized dialysis circumstances and concentrated to 1600 µg mL?1 fusion protein by ultrafiltration. 5 μg mL?1 H2O2 was applied for accelerating the formation of two necessary disulfide bonds. Antimicrobial assays were performed against E. coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, Aspergillus flavus and Candida albicans. Results of antimicrobial tests confirmed the efficiency of BCN-IbAMP4 against all tested microorganisms. Overall, the combination of thymol plus BCN-IbAMP4 increased their antimicrobial activities. MIC, MBC, MFC, FICI and FBCI values showed strong synergistic activity between the two examined compounds. Time kill and growth kinetic studies indicated significant reduction of cell viability during first period of exposure to BCN-IbAMP4 and thymol combination. 相似文献
26.
Seyed Nezamedin Hosseini Amin Javidanbardan Behnaz Sadat Alizadeh Salim 《Preparative biochemistry & biotechnology》2013,43(8):683-692
AbstractThe costly media, inconsistent ligand density, ligand leakage, and possible destabilization of recombinant hepatitis B surface antigen (rHBsAg) particles are main drawbacks of using immunoaffinity chromatography (IAF) in the large-scale downstream processing. In this study, we aimed to use an efficient large-scale purification system as an alternative purification method for immunoaffinity chromatography. For this purpose, we suggested integrating non-affinity chromatographic methods of hydrophobic interaction chromatography (HIC) and size-exclusion chromatography (SEC) for cost-effective purification of rHBsAg expressed in P. pastoris. The optimization of such process is not trivial and straightforward since diverse molecular characteristics of expressed rHBsAg in each type of host cell cause different interactions in non-affinity chromatography processes. The working buffer composition and chromatography parameters are the most influential factors in hydrophobic interaction chromatography. The best result for lab-scale HIC was achieved by using ammonium sulfate buffer in 10% of saturation concentration in pH 7.0 with Butyl-S Sepharose 6 Fast Flow medium and with subsequent Tween-100 and urea elution. In this process, the recovery, purity, and total yield were about 84%, 82%, and 69%, respectively. By scaling-up the HIC and integrating it with Sephacryl S-400?SEC, we obtained highly pure, i.e.,?>?90%, rHBsAg virus-like particles (VLP). 相似文献
27.
Zamani M Sharifi Tehrani A Ahmadzadeh M Ali Abadi AA 《Communications in agricultural and applied biological sciences》2007,72(4):935-939
Epiphytic fluorescent Pseudomonads isolated from the surfaces of citrus leaves and fruits collected from the citrus orchards located in the north of Iran were screened for antagonistic activity against Penicillium digitatum caused agent of green mold of citrus fruit. 9 isolates revealed antagonistic effect in dual culture and then evaluated for production of antimicrobial metabolites such as production hydrogen cyanide on King's B medium containing glycine, production of siderophore on blue CAS-agar medium and production protease enzyme on Skim Milk Agar (SMA) medium. About 28% strains produced hydrogen cyanide, 83% strains produced siderophore and 70% of them produced protease. Antagonistic effects of the screened 9 isolates were studied by inoculating of the infected orange fruits with the bacterium at the concentration of 10(8) cells/ml under sterilized condition at 20 degrees C. The three final screened antagonist isolates were more studied in semi commercial trails in cold storage with dipping of the orange fruits in the bacterial suspension at the concentration of 10(8) cells/ml and then 5 weeks storage at 4 degrees C. The isolate P39 showed to be the most effective for controlling of this disease and decreased the damage by 77.28% respectively. 相似文献
28.
Jaber?NasiriEmail author Mohammad?Reza?NaghaviEmail author Houshang?Alizadeh Mohammad?Reza?Fattahi Moghadam Alireza?Mashouf Mohammad?Nabizadeh 《Acta Physiologiae Plantarum》2015,37(6):110
Attempts were made here to apply a modified analytic hierarchy process (AHP) approach based on refinement assay of dominated alternatives in monitoring the most reliable callus maintenance media (supplemented with l-glutamine and Casamino acid) of Taxus baccata callus cultures in terms of five criteria. Generally, regarding stem-derived calli, 6 out of 18 maintenance media were nominated as non-dominated alternatives, and following AHP ranking test Casamino acid-based media (i.e., A12, A15 and A19) were overall nominated as the premiere. Taking leaf-derived calli into account, only l-glutamine-based media in an ascending order of A8, A4, A6, A5, A9 and A3 were introduced as non-dominated alternatives. Such results connote that l-glutamine-based feeding appears to generate more significant results either for continuous calli growth or taxanes production. In contrast, regarding the second explant, stem, both amino acid supplies had fairly equal worth. Our findings, overall, demonstrate promising applications of the proposed AHP method regarding accurate selection of the best callus maintenance cultures of T. baccata for production of different taxanes including paclitaxel, Baccatin III and 10-deacetylbaccatin III. Similarly, this statistical approach could be also applicable for other crops, for instance, for accurate selection of the best callus cultures/media and consequently production improvement of a given plant secondary metabolite/product. 相似文献
29.
Niloufar Abdollahian Hamideh Ghazizadeh Maryam MohammadiBajgiran Mehran Pashirzad Mahdiyeh Yaghooti Khorasani Mary Kathryn Bohn Shannon Steele Fatemeh Roudi Atieh Kamel Khodabandeh Sara Ghazi Zadeh Iman AlamiArani Seyede Negin Badakhshan Habibollah Esmaily Gordon A. Ferns Reza AssaranDarban Khosrow Adeli Majid GhayourMobarhan 《Journal of cellular and molecular medicine》2023,27(1):158
Age and sex need to be considered in the establishment of reference intervals (RIs), especially in early life when there are dynamic physiological changes. Since data for important biomarkers in healthy neonates and infants are limited, particularly in Iranian populations, we have determined age‐specific RIs for 7 laboratory biochemical parameters. This cross‐sectional study comprised a total of 344 paediatric participants (males: 158, females: 186) between the ages of 3 days and 30 months (mean age: 12.91 ± 7.15 months). Serum levels of creatinine, urea, uric acid, calcium, phosphate, vitamin D and high‐sensitivity C‐reactive protein (hs‐CRP) were measured using an Alpha classic‐AT plus auto‐analyser. We determined age‐specific RIs using CLSI Ep28‐A3 and C28‐A3 guidelines. No sex partitioning was required for any of the biomarkers. Age partitioning was required for kidney function tests and phosphate. The serum concentration of urea and creatinine increased with age, while phosphate and uric acid decreased with age. Age partitioning was not required for serum calcium, vitamin D, and hs‐CRP, which remained relatively constant throughout the age range. Age‐specific RIs for 7 routine biochemical markers were determined to address critical gaps in RIs in early life to help improve clinical interpretation of blood test results in young children, including neonates. Established age partitions demonstrate the biochemical changes that take place during child growth and development. These novel data will ultimately better disease management in the Iranian paediatric population and can be of value to clinical and hospital laboratories with similar populations. 相似文献
30.
White adipose tissue (WAT) is the source of pro- and anti-inflammatory cytokines and we have recently shown that this tissue is a major source of the anti-inflammatory interleukin (IL)-1 receptor antagonist (IL-1Ra). We now aimed at identifying additional adipose-derived cytokines, which might serve as regulators of IL-1Ra. We demonstrate here for the first time that the antiinflammatory cytokine IL-10 is secreted by human WAT explants and that it is up-regulated by LPS and TNF-alpha in vitro, as well as in obesity in humans (2- and 6-fold increase in subcutaneous and visceral WAT, respectively) and rodents (4-fold increase). 相似文献