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81.
Hutchinson AB Patel P Sansom SL Farnham PG Sullivan TJ Bennett B Kerndt PR Bolan RK Heffelfinger JD Prabhu VS Branson BM 《PLoS medicine》2010,7(9):e1000342
Background
Detection of acute HIV infection (AHI) with pooled nucleic acid amplification testing (NAAT) following HIV testing is feasible. However, cost-effectiveness analyses to guide policy around AHI screening are lacking; particularly after more sensitive third-generation antibody screening and rapid testing.Methods and Findings
We conducted a cost-effectiveness analysis of pooled NAAT screening that assessed the prevention benefits of identification and notification of persons with AHI and cases averted compared with repeat antibody testing at different intervals. Effectiveness data were derived from a Centers for Disease Control and Prevention AHI study conducted in three settings: municipal sexually transmitted disease (STD) clinics, a community clinic serving a population of men who have sex with men, and HIV counseling and testing sites. Our analysis included a micro-costing study of NAAT and a mathematical model of HIV transmission. Cost-effectiveness ratios are reported as costs per quality-adjusted life year (QALY) gained in US dollars from the societal perspective. Sensitivity analyses were conducted on key variables, including AHI positivity rates, antibody testing frequency, symptomatic detection of AHI, and costs. Pooled NAAT for AHI screening following annual antibody testing had cost-effectiveness ratios exceeding US$200,000 per QALY gained for the municipal STD clinics and HIV counseling and testing sites and was cost saving for the community clinic. Cost-effectiveness ratios increased substantially if the antibody testing interval decreased to every 6 months and decreased to cost-saving if the testing interval increased to every 5 years. NAAT was cost saving in the community clinic in all situations. Results were particularly sensitive to AHI screening yield.Conclusions
Pooled NAAT screening for AHI following negative third-generation antibody or rapid tests is not cost-effective at recommended antibody testing intervals for high-risk persons except in very high-incidence settings. Please see later in the article for the Editors'' Summary 相似文献82.
The North-East region of India is one of the twelve mega biodiversity region, containing many rare and endangered species. A curated database of medicinal and aromatic plants from the regions called NeMedPlant is developed. The database contains traditional, scientific and medicinal information about plants and their active constituents, obtained from scholarly literature and local sources. The database is cross-linked with major biochemical databases and analytical tools. The integrated database provides resource for investigations into hitherto unexplored medicinal plants and serves to speed up the discovery of natural productsbased drugs. AVAILABILITY: The database is available for free at http://bif.uohyd.ac.in/nemedplant/orhttp://202.41.85.11/nemedplant/ 相似文献
83.
Bioconjugation of L-3,4-dihydroxyphenylalanine containing protein with a polysaccharide 总被引:1,自引:0,他引:1
Ayyadurai N Prabhu NS Deepankumar K Jang YJ Chitrapriya N Song E Lee N Kim SK Kim BG Soundrarajan N Lee S Cha HJ Budisa N Yun H 《Bioconjugate chemistry》2011,22(4):551-555
We describe the simple bioconjugation strategy in combination of periodate chemistry and unnatural amino acid incorporation. The residue specific incorporation of 3,4-dihydroxy-l-phenylalanine can alter the properties of protein to conjugate into the polymers. The homogeneously modified protein will yield quinone residues that are covalently conjugated to nucleophilic groups of the amino polysaccharide. This novel approach holds great promise for widespread use to prepare protein conjugates and synthetic biology applications. 相似文献
84.
85.
Xing G Barr EW Diao Y Hoffart LM Prabhu KS Arner RJ Reddy CC Krebs C Bollinger JM 《Biochemistry》2006,45(17):5402-5412
myo-Inositol oxygenase (MIOX) catalyzes the ring-cleaving, four-electron oxidation of its cyclohexan-(1,2,3,4,5,6-hexa)-ol substrate (myo-inositol, MI) to d-glucuronate (DG). The preceding paper [Xing, G., Hoffart, L. M., Diao, Y., Prabhu, K. S., Arner, R. J., Reddy, C. C., Krebs, C., and Bollinger, J. M., Jr. (2006) Biochemistry 45, 5393-5401] demonstrates by M?ssbauer and electron paramagnetic resonance (EPR) spectroscopies that MIOX can contain a non-heme dinuclear iron cluster, which, in its mixed-valent (II/III) and fully oxidized (III/III) states, is perturbed by binding of MI in a manner consistent with direct coordination. In the study presented here, the redox form of the enzyme that activates O(2) has been identified. l-Cysteine, which was previously reported to accelerate turnover, reduces the fully oxidized enzyme to the mixed-valent form, and O(2), the cosubstrate, oxidizes the fully reduced form to the mixed-valent form with a stoichiometry of one per O(2). Both observations implicate the mixed-valent, diiron(II/III) form of the enzyme as the active state. Stopped-flow absorption and freeze-quench EPR data from the reaction of the substrate complex of mixed-valent MIOX [MIOX(II/III).MI] with limiting O(2) in the presence of excess, saturating MI reveal the following cycle: (1) MIOX(II/III).MI reacts rapidly with O(2) to generate an intermediate (H) with a rhombic, g < 2 EPR spectrum; (2) a form of the enzyme with the same absorption features as MIOX(II/III) develops as H decays, suggesting that turnover has occurred; and (3) the starting MIOX(II/III).MI complex is then quantitatively regenerated. This cycle is fast enough to account for the catalytic rate. The DG/O(2) stoichiometry in the reaction, 0.8 +/- 0.1, is similar to the theoretical value of 1, whereas significantly less product is formed in the corresponding reaction of the fully reduced enzyme with limiting O(2). The DG/O(2) yield in the latter reaction decreases as the enzyme concentration is increased, consistent with the hypothesis that initial conversion of the reduced enzyme to the MIOX(II/III).MI complex and subsequent turnover by the mixed-valent form is responsible for the product in this case. The use of the mixed-valent, diiron(II/III) cluster by MIOX represents a significant departure from the mechanisms of other known diiron oxygenases, which all involve activation of O(2) from the II/II manifold. 相似文献
86.
Anjali Prabhu Qin Xu Michaele B. Manigrasso Moumita Biswas Elizabeth Flynn Radu Iliescu Edwin D. Lephart Christine Maric 《Steroids》2010,75(11):779-787
Our previous studies have shown that diabetes in the male streptozotocin (STZ)-induced diabetic rat is characterized by a decrease in circulating testosterone and concomitant increase in estradiol levels. Interestingly, this increase in estradiol levels persists even after castration, suggesting extra-testicular origins of estradiol in diabetes. The aim of the present study was to examine whether other target organs of diabetes may be sources of estradiol. The study was performed in male Sprague–Dawley non-diabetic (ND), STZ-induced diabetic (D) and STZ-induced diabetic castrated (Dcas) rats (n = 8–9/group). 14 weeks of diabetes was associated with decreased testicular (ND, 26.3 ± 4.19; D, 18.4 ± 1.54; P < 0.05), but increased renal (ND, 1.83 ± 0.92; D, 7.85 ± 1.38; P < 0.05) and ocular (D, 23.4 ± 3.66; D, 87.1 ± 28.1; P < 0.05) aromatase activity. This increase in renal (Dcas, 6.30 ± 1.25) and ocular (Dcas, 62.7 ± 11.9) aromatase activity persisted after castration. The diabetic kidney also had increased levels of tissue estrogen (ND, 0.31 ± 0.01; D, 0.51 ± 0.11; Dcas, 0.45 ± 0.08) as well as estrogen receptor alpha protein expression (ND, 0.63 ± 0.09; D, 1.62 ± 0.28; Dcas, 1.38 ± 0.20). These data suggest that in male STZ-induced diabetic rats, tissues other than the testis may become sources of estradiol. In particular, the diabetic kidney appears to produce estradiol following castration, a state that is associated with a high degree or renal injury. Overall, our data provides evidence for the extra-testicular source of estradiol that in males, through an intracrine mechanism, may contribute to the development and/or progression of end-organ damage associated with diabetes. 相似文献
87.
Marker-assisted improvement of bacterial blight resistance in parental lines of Pusa RH10, a superfine grain aromatic rice hybrid 总被引:2,自引:0,他引:2
S. H. Basavaraj Vikas K. Singh Atul Singh Ashutosh Singh Anita Singh Deepti Anand Sheel Yadav Ranjith K. Ellur Devinder Singh S. Gopala Krishnan M. Nagarajan T. Mohapatra K. V. Prabhu Ashok K. Singh 《Molecular breeding : new strategies in plant improvement》2010,26(2):293-305
Pusa RH10, the widely cultivated superfine grain aromatic rice hybrid, and its parental lines Pusa6B and PRR78 are susceptible to bacterial blight (BB) disease caused by Xanthomonas oryzae pv. oryzae. Pusa1460, a Basmati rice variety, was utilized as the donor for introgressing BB resistance genes xa13 and Xa21 into Pusa6B and PRR78 using a marker-assisted backcross breeding program. The markers RG136 and pTA248 linked to BB resistance genes xa13 and Xa21, respectively, were used for foreground selection. Seventy-four STMS markers polymorphic between Pusa6B and Pusa1460, and 54 STMS markers polymorphic between PRR78 and Pusa1460, were utilized for background selection to recover the recurrent parent genome ranging from 85.14 to 97.30% and 87.04 to 92.81% in the 10 best BC2F5 families of Pusa6B and PRR78, respectively. RM6100, an STMS marker linked to fertility restorer gene (Rf), was used for marker-assisted selection of Rf gene in an improved version of PRR78. The extent of donor segments in the improved version of Pusa6B was estimated to be <0.97 and <2.15 Mb in the genomic regions flanking xa13 and Xa21, respectively, whereas in improved PRR78, it was estimated to be <2.07 and <3.45 Mb in the corresponding genomic regions. Improved lines of Pusa6B and PRR78 showed yield advantages of up to 8.24 and 5.23%, respectively. The performance of the BB-resistant version of Pusa RH10 produced by intercrossing the improved parental lines was on a par with or superior to the original Pusa RH10. 相似文献
88.
Niraikulam Ayyadurai Kanagavel Deepankumar Nadarajan Saravanan Prabhu Nediljko Budisa Hyungdon Yun 《Biotechnology and Bioprocess Engineering》2012,17(4):679-686
Recently, non-canonical amino acids (NCAA) incorporation was developed to enhance the functional properties of proteins. Incorporation of NCAA containing chlorine atom is conceptually an attractive approach to prepare pharmacologically active substances, which is a difficult task since chlorine is bulky atom. In this study, we evaluated the efficiency and extent of in vivo incorporation of tyrosine analogue 3-chlorotyrosine [(3-Cl)Tyr] into the recombinant proteins GFP and GFPHS (highly stable GFP). The incorporation of (3-Cl)Tyr into GFP leads to dramatic reduction in the expression level of protein. On the other hand, the incorporation of (3-Cl)Tyr into GFPHS was expressed well as a soluble form. In addition we used bioinformatics tools for the analysis to explore the possible constraints in micro-environment of each natural amino acid residue to be replaced with chlorine atom accommodation into GFPHS. In conclusion, our approaches are reliable and straightforward way to enhance the translation of chlorinated amino acids into proteins. 相似文献
89.
T. R. Mahalingam S. Vijayalakshmi R. Krishna Prabhu A. Thiruvengadasami Ann Wilber C. K. Mathews K. Radha Shanmugasundaram 《Biological trace element research》1997,57(3):191-206
Blood is one of the widely used specimens for biological trace element research because of its biological significance and
ease of sampling. We have conducted a study of the blood of the Kalpakkam township population for trace and minor elements.
For this purpose, analytical methods have been developed and standardized in our laboratory for the elemental analysis of
blood plasma and red cells. Inductively coupled plasma-mass spectrometry (ICP-MS), a relatively new technique, has been applied
for the analysis of trace elements. Details regarding spectral interference and matrix interference encountered in the analysis
of blood and the methods of correcting them have been discussed. Flame atomic absorption spectrometry (AAS)/atomic emission
spectrometry (AES) has been applied for the determination of minor elements. Precision and accuracy of these methods have
also been discussed. 相似文献
90.
Antiserum to flight-muscle proteins was developed by injecting flight-muscle extract into rabbits. Immunodiffusion tests showed the presence of at least 4 antibodies formed against 4 proteins in the flight-muscle extract. During the 4th day of adult life, while vitellogenesis was under way, 4 proteins antigenically identical to those of flight-muscle extract were found in the blood. These four proteins were found in the first batch of laid eggs under immunodiffusion. The possibility of entry of muscle proteins into oöcytes by way of the blood is discussed. 相似文献