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231.
Denton PW Olesen R Choudhary SK Archin NM Wahl A Swanson MD Chateau M Nochi T Krisko JF Spagnuolo RA Margolis DM Garcia JV 《Journal of virology》2012,86(1):630-634
Here we demonstrate that a combination of tenofovir, emtricitabine, and raltegravir effectively suppresses peripheral and systemic HIV replication in humanized BLT mice. We also demonstrate that antiretroviral therapy (ART)-treated humanized BLT mice harbor latently infected resting human CD4+ T cells that can be induced ex vivo to produce HIV. We observed that the levels of infected resting human CD4+ T cells present in BLT mice are within the range of those observed circulating in patients undergoing suppressive ART. These results demonstrate the potential of humanized BLT mice as an attractive model for testing the in vivo efficacy of novel HIV eradication strategies. 相似文献
232.
233.
Amor EC Villaseñor IM Ghayur MN Gilani AH Choudhary MI 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(1-2):67-71
The hexane extract of Syzygium samarangense (Ss.Hex) dose-dependently (10-1000 microg/ ml) relaxed the spontaneously contracting isolated rabbit jejunum. Four rare C-methylated flavonoids with a chalcone and a flavanone skeleton were isolated from Ss.Hex and were subsequently tested for spasmolytic activity. All flavonoids, identified as 2'-hydroxy-4',6'-dimethoxy-3'-methylchalcone (1), 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (2), 2',4'-dihydroxy-6'-methoxy-3'-methylchalcone (3), and 7-hydroxy-5-methoxy-6,8-dimethyl-flavanone (4), showed dose-dependent spasmolytic activity in the rabbit jejunum with IC50 values of 148.3 +/- 69.4, 77.2 +/- 43.5, 142.4 +/- 58.6 and 178.5 +/- 37.5 microg/ml (mean +/- SEM), respectively. The dihydrochalcone derivative of compound 1, 2'-hydroxy-4',6'-dimethoxy-3'-methyldihydrochalcone (5), when tested for spasmolytic activity, did not significantly relax the smooth muscle relative to the other compounds. Verapamil, a standard spasmolytic, has an IC50 value of 0.16 +/- 0.04 microg/ml. This is the first report of the relaxant activity of chalcones, specifically of compounds 1-3. 相似文献
234.
Activity of Cu2+-diamine oxidase (DAO; E.C.1.4.3.6.) was measured in Vigna radiata (L.) Wilczek cultivars K851, MH8320 and
Pusa Baisakhi in light and in dark during ontogeny of seedlings. DAO activity was always the highest in cv. K851. In both
light and dark grown seedlings maximum DAO activity was detected on day 2 after germination. Thereafter, in light grown seedlings
it declined consistently upto non-detectable levels. In dark, DAO activity was higher than in light and it had the second
maximum on day 7 following a similar declining pattern as observed for the light grown seedlings. The DAO activity was higher
in a shoot apex alongwith leaves than in roots and shoot axis.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
235.
A peroxidase has been purified to homogeneity from Astragalus maritimus seeds using ammonium sulfate precipitation and chromatography on DEAE-cellulose and hydroxylapatite. The purification obtained was 255 fold. The enzyme preparations were homogenous by the criteria of SDS-PAGE and analytical gel electrofocusing. The protein contained 0.11% of iron that corresponds to a minimum molecular size of 50,700. Determinations of molecular size by SDS-PAGE gave values of 48,000 +/- 1,000 while the one obtained by Sephadex gel filtration was 49,000. The pH optimum of the enzyme was 6.0. The activation energy was estimated to be 6 Kcal/mol. The prosthetic group was shown to be ferriprotoporphyrin IX. The presence of 13% neutral sugars was found. The spectrophotometric analysis showed the presence, in the visible region, of absorption maxima at 403, 490 and 633 nm. The Rz value (A403/A275) was 2.7. 相似文献
236.
Domenico Rau Frank J Maier Roberto Papa Anthony H D Brown Virgilio Balmas Eva Saba Wilhelm Schaefer Giovanna Attene 《Génome》2005,48(5):855-869
Pyrenophora teres f. sp. teres mating-type genes (MAT-1: 1190 bp; MAT-2: 1055 bp) have been identified. Their predicted proteins, measuring 379 and 333 amino acids, respectively, are similar to those of other Pleosporales, such as Pleospora sp., Cochliobolus sp., Alternaria alternata, Leptosphaeria maculans, and Phaeosphaeria nodorum. The structure of the MAT locus is discussed in comparison with those of other fungi. A mating-type PCR assay has also been developed; with this assay we have analyzed 150 isolates that were collected from 6 Sardinian barley landrace populations. Of these, 68 were P. teres f. sp. teres (net form; NF) and 82 were P. teres f. sp. maculata (spot form; SF). Within each mating type, the NF and SF amplification products were of the same length and were highly similar in sequence. The 2 mating types were present in both the NF and the SF populations at the field level, indicating that they have all maintained the potential for sexual reproduction. Despite the 2 forms being sympatric in 5 fields, no intermediate isolates were detected with amplified fragment length polymorphism (AFLP) analysis. These results suggest that the 2 forms are genetically isolated under the field conditions. In all of the samples of P. teres, the ratio of the 2 mating types was consistently in accord with the 1:1 null hypothesis. This ratio is expected when segregation distortion and clonal selection among mating types are absent or asexual reproduction is rare. Overall, sexual reproduction appears to be the major process that equalizes the frequencies of the 2 mating types within populations. 相似文献
237.
238.
Dinesh Varshney Dinesh Choudhary Meenu Varshney Namita Singh 《Molecular simulation》2016,42(2):110-121
The lattice contribution to the thermal conductivity (κph) of La0.95Ag0.05MnO3 manganites is theoretically analysed within the framework of Kubo model. The theory is formulated when thermal conduction is limited by the scattering of phonons from defects, grain boundaries, charge carriers, spin waves and phonons. The lattice thermal conductivity dominates in Ag-doped manganites and is artefact of strong phonon–impurity and phonon–phonon scattering mechanism in the ferromagnetic metallic state. The electronic contribution to the thermal conductivity (κe) is estimated following the Wiedemann–Franz law. Another important contribution in the metallic phase should come from spin waves (κm). It is noticed that κm increases with a T2 dependence on the temperature. The behaviour of the thermal conductivity in manganites is determined by competition among the several operating scattering mechanisms for the heat carriers and a balance between electron, magnon and phonon contributions. 相似文献
239.
Photophysical properties of hydroxyphenyl benzazoles and their applications as fluorescent probes to study local environment in DNA,protein and lipid 下载免费PDF全文
Fluorescence techniques have drawn increasing attention because they provide crucial information about molecular interactions in protein–ligand systems beyond that obtained by other methods. The advantage of fluorescence spectroscopy stems from the fact that the majority of molecules in biological systems do not exhibit fluorescence, making fluorescent probes useful with high sensitivity. Also, the fluorescence emission is highly sensitive to the local environment, providing a valuable tool to investigate the nature of binding sites in macromolecules. In this review, we discuss some of the important applications of a class of molecules that have been used as fluorescent probes in a variety of studies. Hydroxyphenyl benzazoles (HBXs) show distinct spectroscopic features that make them suitable probes for the study of certain biological mechanisms in DNA, protein and lipid. In particular, the complex photophysics of 2‐(2′‐hydroxyphenyl)benzoxazole (HBO) and the distinguished fluorescence signatures of its different tautomeric forms make this molecule a useful probe in several applications. Among these are probing the DNA local environment, study of the flexibility and specificity of protein‐binding sites, and detecting the heterogeneity and ionization ability of the head groups of different lipidic phases. The spectroscopy of HBX molecules and some of their chemically modified structures is also reviewed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
240.
Saba M. Lambert Digafe T. Alembo Shimelis D. Nigusse Lawrence K. Yamuah Stephen L. Walker Diana N. J. Lockwood 《PLoS neglected tropical diseases》2016,10(4)