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111.
Vessela D. Kancheva Luciano Saso Petya V. Boranova Abdullah Khan Manju K. Saroj Mukesh K. Pandey Shashwat Malhotra Jordan Z. Nechev Sunil K. Sharma Ashok K. Prasad Maya B. Georgieva Carleta Joseph Anthony L. DePass Ramesh C. Rastogi Virinder S. Parmar 《Biochimie》2010
The chain-breaking antioxidant activities of eight coumarins [7-hydroxy-4-methylcoumarin (1), 5,7-dihydroxy-4-methylcoumarin (2), 6,7-dihydroxy-4-methylcoumarin (3), 6,7-dihydroxycoumarin (4), 7,8-dihydroxy-4-methylcoumarin (5), ethyl 2-(7,8-dihydroxy-4-methylcoumar-3-yl)-acetate (6), 7,8-diacetoxy-4-methylcoumarin (7) and ethyl 2-(7,8-diacetoxy-4-methylcoumar-3-yl)-acetate (8)] during bulk lipid autoxidation at 37 °C and 80 °C in concentrations of 0.01–1.0 mM and their radical scavenging activities at 25 °C using TLC–DPPH test have been studied and compared. It has been found that the o-dihydroxycoumarins 3–6 demonstrated excellent activity as antioxidants and radical scavengers, much better than the m-dihydroxy analogue 2 and the monohydroxycoumarin 1. The substitution at the C-3 position did not have any effect either on the chain-breaking antioxidant activity or on the radical scavenging activity of the 7,8-dihydroxy- and 7,8-diacetoxy-4-methylcoumarins 6 and 8. The comparison with DL-α-tocopherol (TOH), caffeic acid (CA) and p-coumaric acid (p-CumA) showed that antioxidant efficiency decreases in the following sequence: 相似文献
112.
Abdullah Farooque Niharika Singh Jawahar Singh Adhikari Farhat Afrin Bilikere Srinivasa Rao Dwarakanath 《PloS one》2014,9(9)
Two-deoxy-D-glucose (2-DG), an inhibitor of glycolysis differentially enhances the radiation and chemotherapeutic drug induced cell death in cancer cells in vitro, while the local tumor control (tumor regression) following systemic administration of 2-DG and focal irradiation of the tumor results in both complete (cure) and partial response in a fraction of the tumor bearing mice. In the present studies, we investigated the effects of systemically administered 2-DG and focal irradiation of the tumor on the immune system in Ehrlich ascites tumor (EAT) bearing Strain “A” mice. Markers of different immune cells were analyzed by immune-flow cytometry and secretary cytokines by ELISA, besides monitoring tumor growth. Increase in the expression of innate (NK and monocytes) and adaptive CD4+cells, and a decrease in B cells (CD19) have been observed after the combined treatment, suggestive of activation of anti-tumor immune response. Interestingly, immature dendritic cells were found to be down regulated, while their functional markers CD86 and MHC II were up regulated in the remaining dendritic cells following the combination treatment. Similarly, decrease in the CD4+ naïve cells with concomitant increase in activated CD4+ cells corroborated the immune activation. Further, a shift from Th2 and Th17 to Th1 besides a decrease in inflammatory cytokines was also observed in the animals showing complete response (cure; tumor free survival). This shift was also complimented by respective antibody class switching followed by the combined treatment. The immune activation or alteration in the homeostasis favoring antitumor immune response may be due to depletion in T regulatory cells (CD4+CD25+FoxP3+). Altogether, these results suggest that early differential immune activation is responsible for the heterogenous response to the combined treatment. Taken together, these studies for the first time provided insight into the additional mechanisms underlying radio-sensitization by 2-DG in vivo by unraveling its potential as an immune-modulator besides direct effects on the tumor. 相似文献
113.
The anomeric specificity of D-glucose phosphorylation by hepatic glucose-6-phosphatase was examined in rat liver microsomes incubated in the presence of carbamoyl phosphate. At 10 degrees C, the Km for the equilibrated hexose and phosphate donor was close to 56 mM and 11 mM, respectively. The enzymic activity, which was increased in diabetic rats, was about 40% lower in untreated than in sonicated microsomes. No anomeric difference in affinity was found in sonicated microsomes. In untreated microsomes, however, the Km for beta-D-glucose was slightly lower than that for alpha-D-glucose. The maximal velocity was higher with beta- than alpha-D-glucose in both untreated and sonicated microsomes. These data indicate that the phosphotransferase activity of glucose-6-phosphatase cannot account for the higher rate of glycolysis and glycogen synthesis found in hepatocytes exposed to alpha- rather than beta-D-glucose. 相似文献
114.
Phosphate starvation response controls genes required to synthesize the phosphate analog arsenate 下载免费PDF全文
Qian Wang Yoon‐Suk Kang Abdullah Alowaifeer Kaixiang Shi Xia Fan Lu Wang Jonathan Jetter Brian Bothner Gejiao Wang Timothy R. McDermott 《Environmental microbiology》2018,20(5):1782-1793
Environmental arsenic poisoning affects roughly 200 million people worldwide. The toxicity and mobility of arsenic in the environment is significantly influenced by microbial redox reactions, with arsenite (AsIII) being more toxic than arsenate (AsV). Microbial oxidation of AsIII to AsV is known to be regulated by the AioXSR signal transduction system and viewed to function for detoxification or energy generation. Here, we show that AsIII oxidation is ultimately regulated by the phosphate starvation response (PSR), requiring the sensor kinase PhoR for expression of the AsIII oxidase structural genes aioBA. The PhoRB and AioSR signal transduction systems are capable of transphosphorylation cross‐talk, closely integrating AsIII oxidation with the PSR. Further, under PSR conditions, AsV significantly extends bacterial growth and accumulates in the lipid fraction to the apparent exclusion of phosphorus. This could spare phosphorus for nucleic acid synthesis or triphosphate metabolism wherein unstable arsenic esters are not tolerated, thereby enhancing cell survival potential. We conclude that AsIII oxidation is logically part of the bacterial PSR, enabling the synthesis of the phosphate analog AsV to replace phosphorus in specific biomolecules or to synthesize other molecules capable of a similar function, although not for total replacement of cellular phosphate. 相似文献
115.
Shatoor Abdullah S. Al Humayed Suliman Almohiy Hussain M. 《Journal of physiology and biochemistry》2022,78(1):151-168
Journal of Physiology and Biochemistry - This study examined whether astaxanthin (ASX) could alleviate hepatic steatosis in rats fed a high-fat diet (HFD) by modulating the nuclear factor erythroid... 相似文献
116.
117.
Arivalagan Pugazhendhi Sridevi Dhanarani Theivaraj Gowri Manogari Boovaragamoorthy Veerasamy Veeramani Kathirvel Brindhadevi Naif Abdullah Al-Dhabi Mariadhas Valan Arasu Thamaraiselvi Kaliannan 《Saudi Journal of Biological Sciences》2021,28(1):988
Tetracycline (TC) is one of the common antibiotics which is widely used in livestock growth promotion. The prevalent application TC may pave way to progression of antibiotic resistant bacteria. The main objective of this study is to determine the effect of Autothermal Thermophilic Aerobic Digestion (ATAD) on the fate of TC residues found in digested poultry litter. For the determination of TC in poultry litter, thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were done. TLC result revealed that the Rf value of standard TC on TLC plate was 0.97 which correlates with the Rf value of TC at 0, 12, 24 and 36 h of digested poultry litter sample and not at 48, 60 and 72 h. HPLC chromatogram revealed that the limits of detection and the recovery were 5 µg/kg and 96% for standard TC. Linear correlation curves were obtained over the series of 100–500 µg/mL with correlation coefficient of 0.996 and the calibration curve was Y = 0.001X + 0.066. These results confirmed the degradation of TC in ATAD digestion of poultry litter by abiotic processes. 相似文献
118.
Azemi Nur Farah Hani Misnan Rosmilah Keong Bun Poh Mokhtar Marina Kamaruddin Nurhaida Fah Wong Chee Yadzir Zailatul Hani Mohamad Yadzir Hani Mohamad Bakhtiar Faizal Abdullah Noormalin Arip Masita Ateshan Haidr Msahir 《Molecular biology reports》2021,48(10):6709-6718
Molecular Biology Reports - Tropomyosin is a major allergen in crustaceans, including mud crab species, but its molecular and allergenic properties in Scylla olivacea are not well known. Thus, this... 相似文献
119.
A new species of Helophorus Fabricius, 1775 is described from Erzurum, northeastern Turkey: Helophorus erzurumicus. In addition, distributional and morphological notes on H. ponticus Angus, 1988 are presented. 相似文献
120.
When rat pancreatic islets were incubated in the presence of unlabelled D-glucose (16.7 mM) and 3HOH, the production of 3H-labelled material susceptible to be phosphorylated by yeast hexokinase and then detritiated by yeast phosphoglucoisomerase did not exceed 2.66 +/- 0.21 pmol/islet per 180 min, i.e. about 1% of the rate of exogenous D-[5-3H]glucose utilization. Such a material accounted for 43 +/- 4% of the total radioactivity, associated with tritiated hexose(s). It is proposed, therefore, that the futile cycling of D-glucose in the reactions catalyzed in the islet cells by the hexokinase isoenzymes and glucose-6-phosphatase represents a negligible fraction of the total rate of D-glucose phosphorylation. 相似文献