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91.
Farsani Seyed Mohammad Jazaeri Jebbink Maarten F Deijs Martin Canuti Marta van Dort Karel A Bakker Margreet Grady Bart PX Prins Maria van Hemert Formijn J Kootstra Neeltje A van der Hoek Lia 《Virology journal》2013,10(1):1-7
Background
Since we were able to isolate viable virus from brain and lung of H7N1 low pathogenic avian influenza virus (LPAIV) infected chickens, we here examined the distribution of different LPAIV strains in chickens by measuring the viral AI RNA load in multiple organs. Subtypes of H5 (H5N1, H5N2), H7 (H7N1, H7N7) and H9 (H9N2), of chicken (H5N2, H7N1, H7N7, H9N2), or mallard (H5N1) origin were tested. The actual presence of viable virus was evaluated with virus isolation in organs of H7N7 inoculated chickens.Findings
Viral RNA was found by PCR in lung, brain, intestine, peripheral blood mononuclear cells, heart, liver, kidney and spleen from chickens infected with chicken isolated LPAIV H5N2, H7N1, H7N7 or H9N2. H7N7 virus could be isolated from lung, ileum, heart, liver, kidney and spleen, but not from brain, which was in agreement with the data from the PCR. Infection with mallard isolated H5N1 LPAIV resulted in viral RNA detection in lung and peripheral blood mononuclear cells only.Conclusion
We speculate that chicken isolated LPAI viruses are spreading systemically in chicken, independently of the strain. 相似文献92.
93.
94.
Hossein Ghafoori Mansoure Askari Sajjad Sarikhan 《Extremophiles : life under extreme conditions》2016,20(2):115-123
This study reports the purification and characterization of an extracellular haloalkaline serine protease from the moderately halophilic bacterium, Bacillus iranensis, strain X5B. The enzyme was purified to homogeneity by acetone precipitation, ultrafiltration and carboxymethyl (CM) cation exchange chromatography, respectively. The purified protease was a monomeric enzyme with a relative molecular mass of 48–50 kDa and it was inhibited by PMSF indicating that it is a serine-protease. The optimum pH, temperature and NaCl concentration were 9.5, 35 °C and 0.98 M, respectively. The enzyme showed a significant tolerance to salt and alkaline pH. It retained approximately 50 % of activity at 2.5 M NaCl and about 70 % of activity at highly alkaline pH of 11.0; therefore, it was a moderately halophilic and also can be activated by metals, especially by Ca2+. The specific activity of the purified protease was measured to be 425.23 μmol of tyrosine/min per mg of protein using casein as a substrate. The apparent K m and V max values were 0.126 mM and 0.523 mM/min, respectively and the accurate value of k cat was obtained as 3.284 × 10?2 s?1. These special and important characteristics make this serine protease as valuable tool for industrial applications. 相似文献
95.
This study is focused on the depositional model and paleoenvironmental distribution patterns of orbitolinids-rich microfacies in an Upper Cretaceous carbonate succession in the Kuh-e Mazar anticline in Kerman Province, Central Iran. Twelve microfacies indicating a tidal flat (including intertidal and supratidal) and an inner ramp (consisting of subtidal lagoon and orbitolinid–rudist barrier shoal) belonging to a shallow-water ramp-type carbonate platform were recognised. Generally, the orbitolinid associations in the carbonate ramp are indicative of shallow warm waters with normal salinity. The occurrence and abundance of thick or conical orbitolinids in both shoal and lagoon show that such associations were well adapted to different environmental conditions including different depth, substrate stability and water energy. The slightly discoidal, almost discoidal and discoidal forms were only present in the deeper depths of the environment including the lagoon with muddy and more stable substrates and lower water energy. However, the orbitolinids in the inner part of the carbonate ramp were scarce or almost absent in the deep inner to middle lagoon due to the deep restricted environmental conditions unfavourable for benthic marine life. 相似文献
96.
Shima Tavakol Reza Saber Elham Hoveizi Hadi Aligholi Jafar Ai Seyed Mahdi Rezayat 《Molecular neurobiology》2016,53(5):3298-3308
97.
98.
Maliheh Barazandeh Tehrani Zahra Rezaei Mehdi Asadi Hossein Behnammanesh Hamid Nadri Fatemeh Afsharirad Alireza Moradi Bagher Larijani Maryam Mohammadi‐Khanaposhtani Mohammad Mahdavi 《化学与生物多样性》2019,16(7)
A new series of coumarin‐3‐carboxamide‐N‐morpholine hybrids 5a – 5l was designed and synthesized as cholinesterases inhibitors. The synthetic approach for title compounds was started from the reaction between 2‐hydroxybenzaldehyde derivatives and Meldrum's acid to afford corresponding coumarin‐3‐carboxylic acids. Then, amidation of the latter compounds with 2‐morpholinoethylamine or N‐(3‐aminopropyl)morpholine led to the formation of the compounds 5a – 5l . The in vitro inhibition screen against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) revealed that most of the synthesized compounds had potent AChE inhibitory while their BuChE inhibitions are moderate to weak. Among them, propylmorpholine derivative 5g (N‐[3‐(morpholin‐4‐yl)propyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing an unsubstituted coumarin moiety and ethylmorpholine derivative 5d (6‐bromo‐N‐[2‐(morpholin‐4‐yl)ethyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing a 6‐bromocoumarin moiety showed the most activity against AChE and BuChE, respectively. The inhibitory activity of compound 5g against AChE was 1.78 times more than that of rivastigmine and anti‐BuChE activity of compound 5d is approximately same as rivastigmine. Kinetic and docking studies confirmed the dual binding site ability of compound 5g to inhibit AChE. 相似文献
99.
Mohammad Asadi Mohammad Hossein Motevaselian Alireza Moradzadeh Leily Majidi Mohammadreza Esmaeilirad Tao Victor Sun Cong Liu Rumki Bose Pedram Abbasi Peter Zapol Amid P. Khodadoust Larry A. Curtiss Narayana R. Aluru Amin Salehi‐Khojin 《Liver Transplantation》2019,9(9)
Conversion of CO2 to energy‐rich chemicals using renewable energy is of much interest to close the anthropogenic carbon cycle. However, the current photoelectrochemical systems are still far from being practically feasible. Here the successful demonstration of a continuous, energy efficient, and scalable solar‐driven CO2 reduction process based on earth‐abundant molybdenum disulfide (MoS2) catalyst, which works in synergy with an inexpensive hybrid electrolyte of choline chloride (a common food additive for livestock) and potassium hydroxide (KOH) is reported. The CO2 saturated hybrid electrolyte utilized in this study also acts as a buffer solution (pH ≈ 7.6) to adjust pH during the reactions. This study reveals that this system can efficiently convert CO2 to CO with solar‐to‐fuel and catalytic conversion efficiencies of 23% and 83%, respectively. Using density functional theory calculations, a new reaction mechanism in which the water molecules near the MoS2 cathode act as proton donors to facilitate the CO2 reduction process by MoS2 catalyst is proposed. This demonstration of a continuous, cost‐effective, and energy efficient solar driven CO2 conversion process is a key step toward the industrialization of this technology. 相似文献
100.
Zahra Azizollahi Seyed Majid Ghaderian 《International journal of phytoremediation》2019,21(12):1241-1253
AbstractThe objective of this study was to determine the effects of cadmium (Cd) toxicity on accumulation, growth, physiological responses, and biochemical characters in summer savory (Satureja hortensis L.). Plants were subjected to different levels of Cd concentrations including 0 (control), 2.5, 5, and 15?mg L?1 in the growing medium. Cd exposure led to a significant increase in root and shoot Cd content. Calculation of bioaccumulation factor, translocation factor, and transfer coefficient revealed that Cd mostly accumulated in roots of S. hortensis and root to shoot transport was effectively restricted. Cd toxicity negatively affected plant growth and significantly reduced chlorophyll content. Contrarily, proline, soluble and reducing carbohydrates, anthocyanin content, and the activity of antioxidant enzymes significantly increased as a result of Cd exposure. Cd application led to a significant increase in essential oil content of S. hortensis. GC-MS analysis revealed that percentage main constitute of S. hortensi, carvacrol, which determines the quality of oil increased under the highest Cd treatment. Based on our findings, S. hortensis can be considered an invaluable alternative crop for mildly Cd-contaminated soils. Besides, due to the high potential of Cd accumulation in the root, S. hortensis may offer a feasible tool for phytostabilization purposes. 相似文献