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131.
G. K. Chikkappa N. K. Tyagi K. Venkatesh M. Ashish K. V. Prabhu T. Mohapatra A. K. Singh 《Journal of plant biochemistry and biotechnology.》2011,20(1):29-38
Rice the major staple food crop which feeds more than half of the world’s population but, lacks pathway to synthesize and accumulate provitamin A in endosperm therefore rice eaters particularly children, and pregnant women suffer due to vitamin A deficiency. The pathway for provitamin A synthesis in rice endosperm has been engineered and transgenic rice lines have yellow endosperm, called ‘Golden Rice’. The present study aimed at studying the inheritance of transgene(s) in six transgenic events of ‘Golden Rice’ and transfer of provitamin A trait from transgenic lines to a widely grown mega rice variety Swarna. The events E1, R1 and W1 showed normal Mendelian inheritance in F2, BC1F1 and BC1F2 generations. The event W1 was studied in BC1F3 as well and showed normal Mendelian inheritance of 3:1. The inheritance pattern in L1 event in BC1F1 and BC1F2 showed normal Mendelian inheritance following expected ratio 1:1 and 3:1 respectively. The two events G1 and T1 showed distorted segregation in BC1F2 and BC2F2 respectively in Swarna genetic background. In G1 event, transgene inheritance showed segregation distortion in BC1F2 in favour of transgene negative plants. In T1 event, inheritance followed expected Mendelian segregation in BC1F1, BC2F1 and BC2F2, generations. However, when tested against co-dominant inheritance 1:2:1 pattern in BC2F2, segregation distortion was observed with less than the expected transgene homozygotes. While against 3:1 ratio, it showed the expected segregation pattern in BC2F2 generation. Segregation distortion probably due to differential transmission of transgene positive/negative gametes through either/both parents which needs further study. 相似文献
132.
Saurabh Prabhu Sarah R. Dennison Bob Lea Timothy J. Snape Iain D. Nicholl Iza Radecka 《植物科学评论》2013,32(5):303-320
Anionic antimicrobial peptides (AAMPs) have been identified in a wide variety of plant species with net charges that range between ?1 and ?7 and structures that include: extended conformations, α-helical architecture and cysteine stabilized scaffolds. These peptides commonly exist as multiple isoforms within a given plant and have a range of biological activities including the ability to kill cancer cells as well as phytopathogenic bacteria, fungi, pests, molluscs, and other predatory species. In general, the killing mechanisms underpinning these activities are poorly understood although they appear to involve attack on intracellular targets such as DNA along with compromise of cell envelope integrity through lysis of the cell wall via chitin-binding and/or permeabilisation of the plasma membrane via lipid interaction. It is now becoming clear that AAMPs participate in the innate immune response of plants and make a major contribution to the arsenal of defence toxins produced by these organisms to compensate for their lack of some defence mechanisms possessed by mammals, such as mobility and a somatic adaptive immune system. Based on their biological properties, a number of potential uses for plant AAMPs have been suggested, including therapeutically useful anticancer agents and novel antimicrobial compounds, which could be utilized in a variety of scenarios, ranging from the protection of crops to the disinfection of hospital environments. 相似文献
133.
Ashish A. Prabhu 《Preparative biochemistry & biotechnology》2017,47(10):953-962
Pichia pastoris is considered as one of the prominent host extensively used as a platform for heterologous protein production. In the present study, the growth inhibition kinetics of recombinant P. pastoris expressing human interferon gamma was studied under different initial substrate concentrations of gluconate (10–100?g?L?1) and methanol (2–50?g?L?1) in modified FM22 medium. The highest specific growth rate of 0.0206 and 0.019?hr?1 was observed at 60?g?L?1 of gluconate and 10?g?L?1 of methanol, respectively. Various three- and four-parametric Monod-variant models were chosen to analyze the inhibition kinetics. The model parameters as well as goodness of fit were estimated using nonlinear regression analysis. The three-parameter Haldane model was found to be best fit for both gluconate (R2?=?0.95) and methanol substrate (R2?=?0.96). The parameter sensitivity analysis revealed that µmax, Ki, and Ks are the most sensitive parameters for both methanol and gluconate. Different substrate inhibition models were fitted to the growth kinetic data and the additive form of double Webb model was found to be the best to explain the growth kinetics of recombinant P. pastoris. 相似文献
134.
Nimitha S. Prabhu K. Sharmila N. Karunakara Nouf Almousa M. I. Sayyed Sudha D. Kamath 《Luminescence》2022,37(5):828-836
Motivated by our previous study on Sm3+ ions as thermoluminescence (TL) sensitizers to the BaO–ZnO–LiF–B2O3–Yb2O3 glass system, in the current study we examined the effect of Er3+ ion co-doping on the TL characteristics of this glass system. The 4f–4f electronic transitions of the Er3+ and Yb3+ ions were confirmed via the optical absorption spectrum. Notably, the use of Yb3+–Er3+ ions failed to improve the TL intensity, sensitivity, and trap density. However, they enabled the glass system to function as an activator–quencher system. The linearity range and effective atomic number remained unaffected after co-doping. In addition, the problem of anomalous fading caused a remnant signal of just 58% after a week of storage of the Yb3+ monodoped glass. This was resolved by the optimum co-doping of Er3+ ions to achieve an 89% signal. The co-doping of Er3+ ions to the BaO–ZnO–LiF–B2O3–Yb2O3 glass system regulated its thermal stability and therefore supplemented its potential for radiation monitoring in food processing and retrospective dosimetry. 相似文献
135.
Deepti Anand K. V. Prabhu A. K. Singh 《Journal of plant biochemistry and biotechnology.》2012,21(2):173-179
Twenty-five commercially grown Indian rice hybrids developed by both the public and private sectors, were analysed for molecular diversity and identification of simple sequence repeat (SSR) marker(s) that can distinguish them from each other. For diversity analysis, a total of fifty eight SSR markers providing genome wide coverage, were used. Forty out of fifty eight SSR markers were polymorphic amplifying a total of 121 alleles with molecular weight ranging from 70 bp ?C 280 bp. Further, characterisation of these markers was carried out generating parameters of heterozygosity (0.42), polymorphism information content (0.31), probability of identity (4.2?×?10?8) and probability of exclusion (99.99%). Cluster analysis based on a set of fourty highly polymorphic SSR markers generated three groups with dissimilarity index values ranging from 0.0 to 0.8. The hybrids based on common female parent IR58025A grouped together indicating a narrow genetic base of hybrid breeding programme. By combining the rapid and simple method of utilising these unique SSR markers alone or in combination, as molecular tags, identification of all the hybrids was possible even without having their parental lines. Twenty SSR loci produced hybrid specific unique alleles, which will be useful in establishing hybrid??s identity. The results have wide prospective in diversifying the genetic base of hybrid breeding programme, identification of rice hybrids, authentication of genetic purity of hybrid seed and protection of IPR. 相似文献
136.
Dhanya Bythadka Erappa Prabhu Ashwini Rekha Punchappady Devasya 《International microbiology》2022,25(2):285-295
International Microbiology - The marine bacterial exopolysaccharides (EPS) have transfigured the biotech sector with their myriad applications and prospects. This work was carried out to... 相似文献
137.
138.
Stephanie L. Sansom Vimalanand S. Prabhu Angela B. Hutchinson Qian An H. Irene Hall Ram K. Shrestha Arielle Lasry Allan W. Taylor 《PloS one》2010,5(1)
Background
HIV incidence was substantially lower among circumcised versus uncircumcised heterosexual African men in three clinical trials. Based on those findings, we modeled the potential effect of newborn male circumcision on a U.S. male''s lifetime risk of HIV, including associated costs and quality-adjusted life-years saved.Methodology/Principal Findings
Given published estimates of U.S. males'' lifetime HIV risk, we calculated the fraction of lifetime risk attributable to heterosexual behavior from 2005–2006 HIV surveillance data. We assumed 60% efficacy of circumcision in reducing heterosexually-acquired HIV over a lifetime, and varied efficacy in sensitivity analyses. We calculated differences in lifetime HIV risk, expected HIV treatment costs and quality-adjusted life years (QALYs) among circumcised versus uncircumcised males. The main outcome measure was cost per HIV-related QALY saved. Circumcision reduced the lifetime HIV risk among all males by 15.7% in the base case analysis, ranging from 7.9% for white males to 20.9% for black males. Newborn circumcision was a cost-saving HIV prevention intervention for all, black and Hispanic males. The net cost of newborn circumcision per QALY saved was $87,792 for white males. Results were most sensitive to the discount rate, and circumcision efficacy and cost.Conclusions/Significance
Newborn circumcision resulted in lower expected HIV-related treatment costs and a slight increase in QALYs. It reduced the 1.87% lifetime risk of HIV among all males by about 16%. The effect varied substantially by race and ethnicity. Racial and ethnic groups who could benefit the most from circumcision may have least access to it due to insurance coverage and state Medicaid policies, and these financial barriers should be addressed. More data on the long-term protective effect of circumcision on heterosexual males as well as on its efficacy in preventing HIV among MSM would be useful. 相似文献139.
Heavy metal ions have been shown to induce Ca2+ release from skeletal sarcoplasmic reticulum (SR) by binding to free sulfhydryl groups on a Ca2+ channel protein and are now examined in cardiac SR. Ag+ and Hg2+ (at 10-25 microM) induced Ca2+ release from isolated canine cardiac SR vesicles whereas Ni2+, Cd2+, and Cu2+ had no effect at up to 200 microM. Ag(+)-induced Ca2+ release was measured in the presence of modulators of SR Ca2+ release was compared to Ca2(+)-induced Ca2+ release and was found to have the following characteristics. (i) Ag(+)-induced Ca2+ release was dependent on free [Mg2+], such that rates of efflux from actively loaded SR vesicles increased by 40% in 0.2 to 1.0 mM Mg2+ and decreased by 50% from 1.0 to 10.0 mM Mg2+. (ii) Ruthenium red (2-20 microM) and tetracaine (0.2-1.0 mM), known inhibitors of SR Ca2+ release, inhibited Ag(+)-induced Ca2+ release. (iii) Adenine nucleotides such as cAMP (0.25-2.0 mM) enhanced Ca2(+)-induced Ca2+ release, and stimulated Ag(+)-induced Ca2+ release. (iv) Low Ag+ to SR protein ratios (5-50 nmol Ag+/mg protein) stimulated Ca2(+)-dependent ATPase activity in Triton X-100-uncoupled SR vesicles. (v) At higher ratios of Ag+ to SR proteins (50-250 nmol Ag+/mg protein), the rate of Ca2+ efflux declined and Ca2(+)-dependent ATPase activity decreased gradually, up to a maximum of 50% inhibition. (vi) Ag+ stimulated Ca2+ efflux from passively loaded SR vesicles (i.e., in the absence of ATP and functional Ca2+ pumps), indicating a site of action distinct from the SR Ca2+ pump. Thus, at low Ag+ to SR protein ratios, Ag+ is very selective for the Ca2+ release channel. At higher ratios, this selectivity declines as Ag+ also inhibits the activity of Ca2+,Mg2(+)-ATPase pumps. Ag+ most likely binds to one or more sulfhydryl sites "on" or "adjacent" to the physiological Ca2+ release channel in cardiac SR to induce Ca2+ release. 相似文献
140.
M.T. Begonia R. Prabhu J. Liao W.R. Whittington A. Claude B. Willeford J. Wardlaw R. Wu S. Zhang L.N. Williams 《Journal of biomechanics》2014
We induced mild blunt and blast injuries in rats using a custom-built device and utilized in-house diffusion tensor imaging (DTI) software to reconstruct 3-D fiber tracts in brains before and after injury (1, 4, and 7 days). DTI measures such as fiber count, fiber length, and fractional anisotropy (FA) were selected to characterize axonal integrity. In-house image analysis software also showed changes in parameters including the area fraction (AF) and nearest neighbor distance (NND), which corresponded to variations in the microstructure of Hematoxylin and Eosin (H&E) brain sections. Both blunt and blast injuries produced lower fiber counts, but neither injury case significantly changed the fiber length. Compared to controls, blunt injury produced a lower FA, which may correspond to an early onset of diffuse axonal injury (DAI). However, blast injury generated a higher FA compared to controls. This increase in FA has been linked previously to various phenomena including edema, neuroplasticity, and even recovery. Subsequent image analysis revealed that both blunt and blast injuries produced a significantly higher AF and significantly lower NND, which correlated to voids formed by the reduced fluid retention within injured axons. In conclusion, DTI can detect subtle pathophysiological changes in axonal fiber structure after mild blunt and blast trauma. Our injury model and DTI method provide a practical basis for studying mild traumatic brain injury (mTBI) in a controllable manner and for tracking injury progression. Knowledge gained from our approach could lead to enhanced mTBI diagnoses, biofidelic constitutive brain models, and specialized pharmaceutical treatments. 相似文献