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Macus Hao-Ran Bao Chunxue Yang Aki Pui-Wah Tse Lai Wei Derek Lee Misty Shuo Zhang Chi Ching Goh David Kung-Chun Chiu Vincent Wai-Hin Yuen Cheuk-Ting Law Wai-Ching Chin Noreen Nog-Qin Chui Bowie Po-Yee Wong Cerise Yuen-Ki Chan Irene Oi-Lin Ng Clive Yik-Sham Chung Chun-Ming Wong Carmen Chak-Lui Wong 《Cell reports》2021,34(4):108676
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Ammad Ahmad Farooqi Ali Naqi Muhammad Zahid Qureshi Aamir Rana Ammara Khan Asma M. Riaz Syed Muhammad Faheem Afzal Nabeelah Rasheed Shahzad Bhatti 《Cell biochemistry and function》2012,30(7):611-617
Research on prostate cancer progression has focused extensively on the concept of miRNA, which can operate either as promoters or as suppressors of carcinogenesis. Moreover, recent genetic studies and emerging functional work show that strikingly similar and overlapping pathways are involved in prostate carcinogenesis. Unswervingly, these elements constitute a recently explored ‘network of networks’ that dynamically reorganizes during DNA damage and is responsible for positively or negatively regulating genome organization and integrity. We consider these facets of convergence and discuss how insights from diametrically opposed interactions of ataxia–telangiectasia mutated and mitrons can inform us about, and possibly help us to get a step closer to personalized medicine. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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M Ali M Afzal C J Gubler J F Burka 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(4):281-283
A ninhydrin positive compound (L2) now identified as 2-amino-5-(N-ethylcarboxyamido)-pentanoic acid, from unprocessed tea leaves was a potent inhibitor of thrombin-stimulated thromboxane formation in rabbit whole blood (Ali and Afzal; Prostaglandins, Leukotrienes and Medicine, 27: 9, 1987). In the present study, processed and unprocessed tea leaf extracts were given to rats to consume for a period of eight weeks. Cholesterol and thromboxane levels were measured in the serum obtained from clotting the blood at 37 degrees C. A significant reduction in thromboxane levels was observed in rats taking unprocessed tea extract. This reduction was equally distributed in adult as well as in juvenile rats. However no appreciable changes in the levels of thromboxane were noticed in the serum of rats taking processed tea extracts. This might be due to the presence of a labile component which is destroyed during the processing of green tea leaves. A decreased level of cholesterol was observed in rats consuming unprocessed tea extract. This decrease could be linked to the decrease in thromboxane levels as observed. Processed tea refers to commercially available tea of different brands while unprocessed tea refers to dried green tea leaves. 相似文献
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Shazia Khaliq Nosheen Rashid Kalsoom Akhtar Muhammad Afzal Ghauri 《Letters in applied microbiology》2009,49(5):635-640
Aims: To develop solid-state fermentation system (SSF) for hyper production of tylosin from a mutant γ-1 of Streptomyces fradiae NRRL-2702 and its parent strain.
Methods and Results: Various agro-industrial wastes were screened to study their effect on tylosin production in SSF. Wheat bran as solid substrate gave the highest production of 2500 μg of tylosin g−1 substrate by mutant γ-1 against parent strain (300 μg tylosin g−1 substrate). The tylosin yield was further improved to 4500 μg g−1 substrate [70% moisture, 10% inoculum (v/w), pH 9·2, 30°C, supplemental lactose and sodium glutamate on day 9]. Wild-type strain displayed less production of tylosin (655 μg of tylosin g−1 substrate) in SSF even after optimization of process parameters.
Conclusion: The study has shown that solid-state fermentation system significantly enhanced the tylosin yield by mutant γ-1.
Significance and Impact of the Study: This study proved to be very useful and resulted in 6·87 ± 0·30-fold increase in tylosin yield by this mutant when compared to that of wild-type strain. 相似文献
Methods and Results: Various agro-industrial wastes were screened to study their effect on tylosin production in SSF. Wheat bran as solid substrate gave the highest production of 2500 μg of tylosin g
Conclusion: The study has shown that solid-state fermentation system significantly enhanced the tylosin yield by mutant γ-1.
Significance and Impact of the Study: This study proved to be very useful and resulted in 6·87 ± 0·30-fold increase in tylosin yield by this mutant when compared to that of wild-type strain. 相似文献
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Julian A. Zagalak Mirjam Menzi Fabian Schmich Hartmut Jahns Afzal M. Dogar Florian Wullschleger Harry Towbin Jonathan Hall 《RNA (New York, N.Y.)》2015,21(12):2132-2142
Short interfering RNAs (siRNAs) are mediators of RNA interference (RNAi), a commonly used technique for selective down-regulation of target gene expression. Using an equimolar mixture of A, G, C, and U phosphoramidites during solid-phase synthesis, we introduced degenerate positions into RNA guide and passenger strands so that, when annealed, a large pool of distinct siRNA duplexes with randomized base pairs at defined sites was created. We assessed the randomization efficiency by deep sequencing one of the RNAs. All possible individual sequences were present in the pool with generally an excellent distribution of bases. Melting temperature analyses suggested that pools of randomized guide and passenger strands RNAs with up to eight degenerate positions annealed so that mismatched base-pairing was minimized. Transfections of randomized siRNAs (rnd-siRNAs) into cells led to inhibition of luciferase reporters by a miRNA-like mechanism when the seed regions of rnd-siRNA guide strands were devoid of degenerate positions. Furthermore, the mRNA levels of a select set of genes associated with siRNA off-target effects were measured and indicated that rnd-siRNAs with degenerate positions in the seed likely show typical non-sequence-specific effects, but not miRNA-like off-target effects. In the wake of recent reports showing the preponderance of miRNA-like off-target effects of siRNAs, our findings are of value for the design of a novel class of easily prepared and universally applicable negative siRNA controls. 相似文献