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The online photoreaction of the rose bengal photosensitized luminol–copper (II) chemiluminescence (CL) system was used for the determination of β-nicotinamide adenine dinucleotide (NADH) and ethanol (EtOH) in pharmaceutical formulations combined with a flow injection technique. NADH can significantly enhance the CL emission of the reaction. For EtOH, alcohol dehydrogenase in soluble form was utilized in the presence of nicotinamide adenine dinucleotide resulting in NADH production. The limit of detection (3σ blank, 𝑛 = 3) of 4.0 × 10−8 and 2.17 × 10−5 M, and linear range 1.3 × 10−7 to 2.5 × 10−5 M (R2 = 0.9998, n = 6) and 0.11–2.17 × 10−3 M (R2 = 0.9996, n = 6) were obtained for NADH and EtOH respectively. The injection rate was 100 h−1 with a relative standard deviation (n = 3) of 1.5–4.8% in the range studied for both analytes. The procedure was satisfactorily applied to pharmaceutical formulations with recoveries in the range 91.6 ± 3.0% to 110 ± 2.0% for NADH and 88 ± 3.0% to 95.4 ± 4.0% for EtOH. The results obtained were very consistent and did not differ considerably from the reported approaches at a 95% confidence limit. The possible mechanism of the CL reaction is also explained briefly. 相似文献
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M Rahimnejad GD Najafpour AA Ghoreyshi F Talebnia GC Premier G Bakeri JR Kim SE Oh 《Journal of microbiology (Seoul, Korea)》2012,50(4):575-580
Microbial fuel cells (MFCs) have been shown to be capable of clean energy production through the oxidation of biodegradable organic waste using various bacterial species as biocatalysts. In this study we found Saccharomyces cerevisiae, previously known electrochemcially inactive or less active species, can be acclimated with an electron mediator thionine for electrogenic biofilm formation in MFC, and electricity production is improved with facilitation of electron transfer. Power generation of MFC was also significantly increased by thionine with both aerated and non-aerated cathode. With electrochemically active biofilm enriched with swine wastewater, MFC power increased more significantly by addition of thionine. The optimum mediator concentration was 500 mM of thionine with S. cerevisae in MFC with the maximum voltage and current generation in the microbial fuel cell were 420 mV and 700 mA/m(2), respectively. Cyclic voltametry shows that thionine improves oxidizing and reducing capability in both pure culture and acclimated biofilm as compared to non-mediated cell. The results obtained indicated that thionine has great potential to enhance power generation from unmediated yeast or electrochemically active biofilm in MFC. 相似文献
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Hina Gul Muhammad Awais Salina Saddick Yazeed Ahmed Falak Sher Khan Eilaf Ahmed Umara Afzal Syed Muhammad Zaigham Abbas Naqvi Muhammad Asghar Khan Muhammad Gulfraz Ghazala Kaukab Raja 《Saudi Journal of Biological Sciences》2021,28(1):247-254
Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines. 相似文献
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Mahbobeh Zamani Babgohari Ali Niazi Ali Asghar Moghadam Tahereh Deihimi Esmaeil Ebrahimie 《In vitro cellular & developmental biology. Plant》2013,49(2):97-106
Exclusion of sodium ions from cells is one of the key salinity tolerance mechanisms in plants. The high-affinity cation transporter (HKT1;5) is located in the plasma membrane of the xylem, excluding Na+ from the parenchyma cells to reduce Na+ concentration. The regulatory mechanism and exact functions of HKT genes from different genotypic backgrounds are relatively obscure. In this study, the expression patterns of HKT1;5 in A and D genomes of wheat were investigated in root and leaf tissues of wild and domesticated genotypes using real-time PCR. In parallel, the K+/Na+ ratio was measured in salt-tolerant and salt-sensitive cultivars. Promoter analysis were applied to shed light on underlying regulatory mechanism of the HKT1;5 expression. Gene isolation and qPCR confirmed the expression of HKT1;5 in the A and D genomes of wheat ancestors (Triticum boeoticum, AbAb and Aegilops crassa, MMDD, respectively). Interestingly, earlier expression of HKT1;5 was detected in leaves compared with roots in response to salt stress. In addition, the salt-tolerant genotypes expressed HKT1;5 before salt-sensitive genotypes. Our results suggest that HKT1;5 expression follows a tissue- and genotype-specific pattern. The highest level of HKT1;5 expression was observed in the leaves of Aegilops, 6 h after being subjected to high salt stress (200 mM). Overall, the D genome allele (HKT1;5-D) showed higher expression than the A genome (HKT1;5-A) allele when subjected to a high NaCl level. We suggest that the D genome is more effective regarding Na+ exclusion. Furthermore, in silico promoter analysis showed that TaHKT1;5 genes harbor jasmonic acid response elements. 相似文献
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Ali Asghar Moghadam Eemaeil Ebrahimie Seyed Mohsen Taghavi Ali Niazi Mahbobeh Zamani Babgohari Tahereh Deihimi Mohammad Djavaheri Amin Ramezani 《Molecular biotechnology》2013,54(3):756-769
A small number of stress-responsive genes, such as those of the mitochondrial F1F0-ATP synthase complex, are encoded by both the nucleus and mitochondria. The regulatory mechanism of these joint products is mysterious. The expression of 6-kDa subunit (MtATP6), a relatively uncharacterized nucleus-encoded subunit of F0 part, was measured during salinity stress in salt-tolerant and salt-sensitive cultivated wheat genotypes, as well as in the wild wheat genotypes, Triticum and Aegilops using qRT-PCR. The MtATP6 expression was suddenly induced 3 h after NaCl treatment in all genotypes, indicating an early inducible stress-responsive behavior. Promoter analysis showed that the MtATP6 promoter includes cis-acting elements such as ABRE, MYC, MYB, GTLs, and W-boxes, suggesting a role for this gene in abscisic acid-mediated signaling, energy metabolism, and stress response. It seems that 6-kDa subunit, as an early response gene and nuclear regulatory factor, translocates to mitochondria and completes the F1F0-ATP synthase complex to enhance ATP production and maintain ion homeostasis under stress conditions. These communications between nucleus and mitochondria are required for inducing mitochondrial responses to stress pathways. Dual targeting of 6-kDa subunit may comprise as a mean of inter-organelle communication and save energy for the cell. Interestingly, MtATP6 showed higher and longer expression in the salt-tolerant wheat and the wild genotypes compared to the salt-sensitive genotype. Apparently, salt-sensitive genotypes have lower ATP production efficiency and weaker energy management than wild genotypes; a stress tolerance mechanism that has not been transferred to cultivated genotypes. 相似文献
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Saied Ghadimi Ali Asghar Ebrahimi Valmoozi Mehrdad Pourayoubi Keyvan Asad Samani 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):556-561
Phosphoramido acid esters (CH3)2NP(O)X(p-OC6H4-CH3) (containing P-Cl (1), P-O (2), P-F (3), P-CN (5), and P-N (4,6) bonds, X for 2, 4 and 6 is OCH3, (C2H5)2N and morpholin) have been synthesized to investigate the structure-activity study of AChE enzyme inhibition, through the parameters logP, δ31P and IC50. After their characterization by 31P, 31P{1H}, 13C, 1H NMR, IR and mass spectroscopy, the parameters logP and δ31P (31P chemical shift in NMR) were used to evaluated the lipophilicity and electronical properties. The ability of compounds to inhibit human AChE was predicted by PASS software (version 1.193), and experimentally evaluated by a modified Ellman's assay. 相似文献
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Asghar Mesbahi Seyed-Salman Zakariaee 《Reports of Practical Oncology and Radiotherapy》2013,18(3):148-152
Background
In radiation therapy with orthovoltage units, the tube design has a crucial effect on its dosimetric features.Aim
In this study, the effect of anode angle on photon beam spectra, depth dose and photon fluence per initial electron was studied for a commercial orthovoltage unit of X-RAD320 biological irradiator.Materials and methods
The MCNPX MC code was used for modeling in the current study. We used the Monte Carlo method to model the X-RAD320 X-ray unit based on the manufacturer provided information. The MC model was validated by comparing the MC calculated photon beam spectra with the results of SpekCalc software. The photon beam spectra were calculated for anode angles from 15 to 35 degrees. We also calculated the percentage depth doses for some angles to verify the impact of anode angle on depth dose. Additionally, the heel effect and its relation with anode angle were studied for X-RAD320 irradiator.Results
Our results showed that the photon beam spectra and their mean energy are changed significantly with anode angle and the optimum anode angle of 30 degrees was selected based on less heel effect and appropriate depth dose and photon fluence per initial electron.Conclusion
It can be concluded that the anode angle of 30 degrees for X-RAD320 unit used by manufacturer has been selected properly considering the heel effect and dosimetric properties. 相似文献9.
Tabatabaei Seyedeh Narjes Abdoli Asghar Hashemzadeh Segherloo Iraj Normandeau Eric Ahmadzadeh Faraham Nejat Farshad Bernatchez Louis 《Hydrobiologia》2020,847(16):3339-3353
Hydrobiologia - Many populations of Caspian Sea trout (Salmo caspius)—a nationally endangered species in Iran—have been extirpated or depleted due to anthropogenic impacts. The Lar... 相似文献
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Mahjabeen N. Sarwar M. Y. Saleem M. Asghar Q. Iqbal 《Archives Of Phytopathology And Plant Protection》2013,46(7):766-782
Ten tomato genotypes were screened for their resistance against cucumber mosaic virus (CMV) and its vector Myzus persicae under natural infection in field, using aphids M. persicae under net-house and mechanical inoculation under greenhouse. Large differences were observed among genotypes for infection percentage (IP) and severity index (SI) among the testing methods used. All genotypes showing tolerance to CMV in the field or through aphid inoculation, however, become susceptible and highly susceptible after mechanical inoculation. All the test genotypes also showed susceptibility to the aphid M. persicae population. Plants inoculated with CMV showed substantial decrease in yield and yield-contributing parameters which varied with cultivars that probably depended upon its genetic make up. All the test genotypes exhibited 0.97–30.19% decrease in plant height, 11.47–52.65% decrease in root length, 46.56–95.56% decrease in fresh plant weight, 65.78–92.84% decrease in root fresh weight, 19.97–87.65% decrease in the dry weight of plants, 75.63–95.43% decrease in dry root weight, 69.51–95.65% reduction in the number of fruits and 89.04–99.89% decrease in yield per plants. After 15 days of inoculation, the quantitative analysis using double beam spectrophotometer showed an increase in total phenolics in CMV-inoculated plants as compared to un-inoculated plants among genotypes. Similarly the thin layer chromatography (TLC) on silica gel G indicated that the number of phenolic compounds was increased in most of the inoculated genotypes while in others they were either decreased or remained same. 相似文献