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71.
Comparison of the effects of poultry manure and its biochar on barley growth in petroleum-contaminated soils 总被引:1,自引:0,他引:1
Maryam Barati Dariush Mowla Sedigheh Safarzadeh 《International journal of phytoremediation》2018,20(2):98-103
This study was conducted to evaluate and compare the effectiveness of two organic amendments [poultry manure (PM) and poultry manure biochar (PMB)] for the degradation of petroleum hydrocarbons in contaminated soils by barley plant at three levels of total petroleum hydrocarbons (TPHs) during 5 months under greenhouse conditions. TPHs removal efficiency and microbial respiration were shown to be higher at soil-cultivated plant than at uncultivated soil and in lowest level of contamination rather than other levels of contamination and at organic amendment treatment than unamended soil. Soil microbial respiration and TPHs degradation in the rhizosphere of barley increased by 15.64 and 12.74% for PM-amended treatment and 28.07 and 26.83% for PMB-amended treatment, respectively, in the 4% TPHs level compared with unamended treatment. Comparison of two amendments showed that in PMB treatment soil, highest dry weight, microbial respiration, and TPHs degradation potential were observed. 相似文献
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Nobakht-Haghighi Navid Rahimifard Mahban Baeeri Maryam Rezvanfar Mohammad Amin Moini Nodeh Shermineh Haghi-Aminjan Hamed Hamurtekin Emre Abdollahi Mohammad 《Molecular and cellular biochemistry》2018,449(1-2):267-276
Molecular and Cellular Biochemistry - Oxidative stress has been involved in the aging process and the pathogenesis of type-2 diabetes, which is a serious health problem worldwide. This study... 相似文献
74.
Maryam Gazor Seyed Siamak Ashraf Talesh Alireza kavianpour Maryam Khatami Amin Javidanbardan Seyed Nezamedin Hosseini 《Biotechnology and Bioprocess Engineering》2018,23(1):49-54
In biotechnological processes, often cell disruption has been an inevitable step as current host cells express most of the desired products intracellularly. Thus, an appropriate cell disruption technique must be selected considering different factors including the target product, process scale, and cell wall structure. In the current study, as a novel method, the efficacy of cell disruption via laser was tested qualitatively and quantitatively in batch and continuous systems, respectively. Laser-induced cell lysis can be a clean, rapid and convenient alternative to the other conventional disruption techniques. Our investigations in the continuous system with a flow rate of 800 μL/sec proved efficient (~ 90%) Pichia pastoris cell disruption at the wavenumber 1,064 nm with the energy input of 284 mW after four complete rounds of circulation. The main mechanism of cell disruption is assumed to be thermolysis via instant heat increase in the laser-treated spot. The results of the current study showed that continuous laser system could be applied in laboratory and industry scale for cell disruption. 相似文献
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BACKGROUND: Calpains are intracellular, calcium-sensitive, neutral cysteine proteases that play crucial roles in many physiological and pathological processes. Calpain regulation is complex and activity is poorly correlated with calpain protein levels. Therefore a full understanding of calpain function requires robust methods for measuring activity. METHODS: We describe and characterize a flow cytometric method for measuring calpain activity in live cells. This method uses the BOC-LM-CMAC reagent that readily diffuses into cells where it reacts with free thiols to enhance retention. RESULTS: We show that the reagent is cleaved specifically by calpains and follows saturation kinetics. We use the assay to measure calpain activation following PDGF stimulation of rat fibroblasts. We also show that the calpain inhibitor PD150606 inhibits calpain with a K(i) of 12.5 muM and show that Mek inhibitors PD89059 and U0126 also suppress calpain activity. We also show that the assay can measure calpain activity in subpopulations of cells present in unfractionated cord blood or in HL60 human myelomonocytic leukemia cells. CONCLUSION: Taken together, these experiments demonstrate that this assay is a reliable and useful method for measuring calpain activity in multiple cell types. 相似文献
76.
The diagnostic and prognostic value of circulating microRNAs in coronary artery disease: A novel approach to disease diagnosis of stable CAD and acute coronary syndrome 下载免费PDF全文
77.
Molecular dynamics study of biodegradation of azo dyes via their interactions with AzrC azoreductase
Hamed Haghshenas Maryam Kay Fariba Dehghanian 《Journal of biomolecular structure & dynamics》2016,34(3):453-462
Azo dyes are one of the most important class of dyes, which have been widely used in industries. Because of the environmental pollution of azo dyes, many studies have been performed to study their biodegradation using bacterial systems. In present work, the AzrC of mesophilic gram-positive Bacillus sp. B29 has been considered to study its interaction with five common azo dyes (orange G, acid red 88, Sudan I, orange I, and methyl red). The molecular dynamics simulations have been employed to study the interaction between AzrC and azo dyes. The trajectory was confirmed using root mean square deviation and the root mean square fluctuation analyses. Then, the hydrogen bond and alanine scanning analyses were performed to reveal active site residues. Phe105 (A), Phe125 (B), Phe172 (B), and Pro132 (B) have been found as the most important hydrophobic residues whereas Asn104 (A), Tyr127 (B), and Asn187 (A) have key role in making hydrogen bond. The results of molecular mechanics Poisson–Boltzmann surface area and molecular mechanics generalized Born surface area calculations proved that the hydrophobic azo dyes like Acid red 88 binds more tightly to the AzrC protein. The calculated data suggested MR A 121 (B) I as a potential candidate for improving the AzrC–MR interactions. 相似文献
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Honarbakhsh M Villafane AA Ruhl I Sannino D Bini E 《Biotechnology and bioengineering》2012,109(7):1881-1886
Mesophilic glucuronidases are the most widely used reporters of gene expression in plants, but unsuitable as reporters in (hyper-)thermophiles due their insufficient thermal stability. Here we present the native 66.8 kDa thermostable β-glucuronidase of Sulfolobus solfataricus. The enzyme activity is characterized in a wide temperature range ideal for, but not limited to, in vivo genetic study of hyperthermophiles. As a proof of concept, we demonstrate its use as a reporter of gene expression in Sulfolobus, by monitoring a promoter fusion created with the β-glucuronidase coding gene gusB and a copper-responsive promoter. 相似文献