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141.
Hossein Forghani Mahin Jamshidi Makiani Hossein Zarei Jaliani Mina Boustanshenas Seyed Mohsen Zahraei 《Iranian Biomedical Journal》2021,25(1):33
Background:Some resources have suggested that genetically inactivated PTs bear a more protective effect than chemically inactivated products. This study aimed to produce new version of PT, by cloning an inactive PTS1 in a fusion form with N-terminal half of the LLO pore-forming toxin. Methods:Deposited pdb structure file of the PT was used to model an extra disulfide bond. Codon-optimized ORF of the PTS1 was used to make recombinant constructs of PTS1 and LLO-PTS1 in the pPSG-IBA35 vector. The recombinant PTS1 and LLO-PTS1 proteins were expressed in BL21 DE3 and SHuffle T7 strains of E. coli and purified by affinity chromatography. Cytotoxic effects of the recombinant proteins were examined in the MCF-7 cell line. Results:The purity of the products proved to be more than 85%, and the efficiency of the disulfide bond formation in SHuffle T7 strain was higher than BL21 DE3 strain. No cytotoxicity of the recombinant proteins was observed in MCF-7 cells. Soluble recombinant PTS1 and LLO-PTS1 proteins were produced in SHuffle T7 strain of E. coli with high efficiency of disulfide bonds formation. Conclusion:The LLO-PTS1 with corrected disulfide bonds was successfully expressed in E. coli SHuffle T7 strain. Due to the safety for human cells, this chimeric molecule can be an option to prevent pertussis disease if its immunostimulatory effects would be confirmed in the future. Key Words: Adjuvant, Cloning, Fusion protein, Pertussis toxin 相似文献
142.
Effect of preceding crops and their residues on availability of zinc in a calcareous Zn-deficient soil 总被引:1,自引:0,他引:1
Hadi Habiby Majid Afyuni Amir Hossein Khoshgoftarmanesh Rainer Schulin 《Biology and Fertility of Soils》2014,50(7):1061-1067
Limited information is available on the effect of preceding crop on phytoavailability of zinc (Zn) in soil. This pot experiment examined the effect of four preceding crops including clover, sunflower, safflower, and sorghum residues on shoot and grain Zn uptake by two wheat genotypes differing in Zn-deficiency tolerance Back Cross and Kavir in a calcareous Zn-deficient soil. Incorporation of all preceding crop residues into the soil significantly increased organic matter (OM) content, dissolved organic C (DOC), and diethylene triamine pentaacetic acid (DTPA) extractable Zn concentration in the soil. Residues of safflower and clover had the greatest effect on increasing DOC. Shoot and grain Zn concentrations were increased by incorporating all pre-crop residues into the soil although this increase was greater at safflower and clover treatments. Incorporation of sorghum residues into the soil had a negative effect on shoot and grain dry matter yield of wheat. Incorporation of safflower and clover residues into the soil increased Zn uptake by wheat shoot and grain. There was a positive significant correlation between shoot and grain Zn concentration with DOC in soil solution. It shows that DOC, produced from decomposition of crop residues, has facilitated Zn uptake by roots of wheat plants and particularly its transfer to grains. 相似文献
143.
Amir Hossein Alavi Amir Hossein Gandomi Ali Mollahassani Ali Akbar Heshmati Azadeh Rashed 《植物养料与土壤学杂志》2010,173(3):368-379
This study considers the use of artificial neural networks (ANNs) to predict the maximum dry density (MDD) and optimum moisture content (OMC) of soil‐stabilizer mix. Multilayer perceptron (MLP), one of the most widely used ANN architectures in the literature, is utilized to construct comprehensive and accurate models relating the MDD and OMC of stabilized soil to the properties of natural soil such as particle‐size distribution, plasticity, linear shrinkage, and the type and quantity of stabilizing additives. Five ANN models are constructed using different combinations of the input parameters. Two separate sets of ANN prediction models, one for MDD and the other for OMC, and also a combined ANN model for multiple outputs are developed using the potentially influential input parameters. Relative‐importance values of various inputs of the models are calculated to determine the significance of each of the predictor variables to MDD and OMC. Inferring the most relevant input parameters based on Garson's algorithm, modified ANN models are separately developed for MDD and OMC. The modified ANN models are utilized to introduce explicit formulations of MDD and OMC. A parametric study is also conducted to evaluate the sensitivity of MDD and OMC due to the variation of the most influencing input parameters. A comprehensive set of data including a wide range of soil types obtained from the previously published stabilization test results is used for training and testing the prediction models. The performance of ANN‐based models is subsequently analyzed and compared in detail. The results demonstrate that the accuracy of the proposed models is satisfactory as compared to the experimental results. 相似文献
144.
Ghiasian SA Maghsood AH Yazdanpanah H Shephard GS Van Der Westhuizen L Vismer HF Rheeder JP Marasas WF 《Journal of agricultural and food chemistry》2006,54(16):6118-6122
A total of 52 corn samples collected in 2000 from four main corn production provinces of Iran (Fars, Kermanshah, Khuzestan, and Mazandaran) were analyzed for contamination with Fusarium verticillioides and fumonisins (FB(1), FB(2), FB(3), and 3-epi-FB(3)). The mean incidence of F. verticillioides (percent of kernels infected) for these four areas was 26.7, 21.4, 24.9, and 59.0%, respectively. The incidence in Mazandaran was significantly (p < 0.05) above that of the other areas. All samples from Mazandaran were contaminated with fumonisins with a mean level of total fumonisins of 10674 microg/kg. In contrast, the incidence of fumonisin contamination above 10 microg/kg was 53 (8/15), 42 (5/12), and 57% (8/14) in the samples from Fars, Kermanshah, and Khuzestan, respectively, and the corresponding mean total fumonisin levels were 215, 71, and 174 microg/kg, respectively. No statistical differences (p > 0.05) were observed in the fumonisin levels of the corn samples from these three provinces, which were significantly (p < 0.05) lower than the fumonisin contamination in samples from Mazandaran. 相似文献
145.
Mirdehghan SH Rahemi M Serrano M Guillén F Martínez-Romero D Valero D 《Journal of agricultural and food chemistry》2006,54(22):8495-8500
Heat treatments have been used to extend storability of several fruits, although no information is available about their effects on nutritive and functional properties in pomegranates, which was the objective of this research. Thus, pomegranate fruits were heat treated (dips at 45 degrees C for 4 min) and stored at 2 degrees C for 90 days. Every 15 days, samples were taken and further stored 2 days at 20 degrees C for shelf life study. Arils from heat-treated pomegranates exhibited higher total antioxidant activity than controls, which was correlated primarily to the high levels of total phenolics and to lesser extent to ascorbic acid and anthocyanin contents. Additionally, the levels of sugars (glucose and fructose) and organic acids (malic, citric, and oxalic acids) remained also at higher concentrations in arils from treated fruits. With this simple and non-contaminant technology, the functional and nutritive properties, after long periods of storage, could then be even greater than in recently harvested fruits, thus providing a high content in health-beneficial compounds to consumers after the intake of these fruits. 相似文献
146.
Seyed Daryoush Moghaddas Asghar Abdoli Bahram H. Kiabi Hossein Rahmani Lorenzo Vilizzi Gordon H. Copp 《Fisheries Management and Ecology》2021,28(1):28-39
Risk screening tools play a crucial role in identifying potential high-risk non-native (NN) fish species. In this study, potentially invasive NN fish species in the Anzali Wetland Complex (AWC), which is located on the south coast of the Caspian Sea (Iran), were identified using the Aquatic Species Invasiveness Screening Kit (AS-ISK). Twenty-nine freshwater fish species were screened of which 13 exist in the AWC and 16 in close proximity to it (“horizon” species). Receiver operating characteristic curve analysis showed that AS-ISK could discriminate reliably between non-invasive and invasive fish species for the AWC. Mean threshold scores were 3.25 for the Basic Risk Assessment (BRA) and 11.75 for the BRA + CCA (BRA + Climate Change Assessment), and these, respectively, classified 89.7% and 86.2% of the species as high risk. The CCA resulted in an increase in the BRA scores for 86.2% of the species, suggesting the need to account in future NN species management for a likely increased invasiveness of those species under future climate conditions. These results suggest that AS-ISK could prove an effective tool for identifying potentially invasive NN freshwater fishes in other wetlands of the Caspian Sea basin. 相似文献
147.
Saeidi Z Vatandoost H Akhavan AA Yaghoobi-Ershadi MR Rassi Y Sheikh Z Arandian MH Jafari R Sanei Dehkordi AR 《Pest management science》2012,68(5):669-675
BACKGROUND: Phelebotumus papatsi is considered to be the main vector of zoonotic cutaneous leishmaniasis as well as sand fly fever in Iran. There are several measures for vector control, with emphasis on insecticides. The objective of this study was to determine the baseline susceptibility of this vector to the commonly used insecticides in an endemic focus of the disease in central Iran. P. papatasi collected from the field were used for susceptibility status. Its baseline susceptibility to DDT and pyrethroids was assessed on about 6866 specimens collected from Badrood rural district, Esfahan Province, Iran, during the summer of 2010. The LT50 and LT90 values were measured according to the World Health Organisation (WHO) test using probit analysis and regression lines. RESULTS: Results of tests against female P. papatasi revealed LT50 values to DDT 4%, permethrin 0.75%, deltamethrin 0.1%, cyfluthrin 0.15% and lambdacyhalothrin 0.05% of 1104.97, 182.35, 26.79, 15.42 and 1.48 s respectively. The figures for male P. papatasi were 973.51, 59.5, 4.4, 2.65 and 1.5. CONCLUSION: The results of this study provide a guideline for implementation of different vector control measures. Furthermore, guidelines are needed for monitoring and evaluation of insecticide susceptibility tests against sand flies. Copyright © 2012 Society of Chemical Industry 相似文献
148.
Zhou Y Fuentes-Hernandez C Shim J Meyer J Giordano AJ Li H Winget P Papadopoulos T Cheun H Kim J Fenoll M Dindar A Haske W Najafabadi E Khan TM Sojoudi H Barlow S Graham S Brédas JL Marder SR Kahn A Kippelen B 《Science (New York, N.Y.)》2012,336(6079):327-332
Organic and printed electronics technologies require conductors with a work function that is sufficiently low to facilitate the transport of electrons in and out of various optoelectronic devices. We show that surface modifiers based on polymers containing simple aliphatic amine groups substantially reduce the work function of conductors including metals, transparent conductive metal oxides, conducting polymers, and graphene. The reduction arises from physisorption of the neutral polymer, which turns the modified conductors into efficient electron-selective electrodes in organic optoelectronic devices. These polymer surface modifiers are processed in air from solution, providing an appealing alternative to chemically reactive low-work function metals. Their use can pave the way to simplified manufacturing of low-cost and large-area organic electronic technologies. 相似文献
149.
150.
Jiriaei Fatemeh Kazemi-Bonchenari Mehdi Moradi Mohammad Hossein Mirmohammadi Davood 《Tropical animal health and production》2020,52(2):829-837
Tropical Animal Health and Production - The effects of feeding corn steep liquor (CSL; 420 g/kg crude protein, DM basis) along with different cereal grains on performance, digestibility,... 相似文献