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41.
Expression of cell-intrinsic antiviral factors suppresses HIV-1 replication. We hypothesized that cellular activation modulates host restriction and susceptibility to HIV-1 infection. We measured the gene expression of 34 antiviral factors in healthy peripheral blood mononuclear cells (PBMC). Cellular activation induced expression of interferon-stimulated gene 15 (ISG15), tripartite motif 5α (TRIM5α), bone marrow stromal cell antigen 2 (BST-2)/tetherin, and certain apolipoprotein B mRNA editing enzyme 3 (APOBEC3) family members. Expression of RTF1, RNA polymerase II-associated factor 1 (PAF1), TRIM11, TRIM26, and BST-2/tetherin correlated with decreased HIV-1 infectivity. This report demonstrates synchronous effects of activation-induced antiviral genes on HIV-1 infectivity, providing candidates for pharmacological manipulation.  相似文献   
42.
Fate of Transforming Deoxyribonucleate in Bacillus subtilis   总被引:12,自引:24,他引:12       下载免费PDF全文
The majority of donor deoxyribonucleate (DNA) at early stages after uptake was found in a complex with a cell component which changes its buoyant behavior on equilibrium density gradients. Analysis of the recipient cell lysates, after treatment to dissociate the complex, showed about two-thirds of the donor molecules in denatured form and the rest associated with recipient DNA. Incubation of cells after DNA uptake leads to the disappearance of denatured donor DNA and to the increase of donor label associated with recipient DNA. Some characteristics of a component from intact cells or spheroplasts with affinity for denatured Bacillus subtilis DNA are described.  相似文献   
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BACKGROUND: Valproic acid (VPA) is an anticonvulsant drug that is widely used therapeutically for a variety of neurological conditions. VPA is also well known for its teratogenic potential in both humans and experimental animal models. The typical malformations observed following VPA exposure include neural tube defects (NTDs) and craniofacial and skeletal malformations. Nevertheless, the mechanisms underlying VPA's anticonvulsant efficacy or its teratogenicity remain to be elucidated. It was recently suggested that a relationship exists between VPA exposure and the cellular depletion of myo-inositol (INO). Furthermore, INO has been shown to rescue NTDs in the curly tail mouse. The aim of this study was to investigate the interactions of VPA and INO in the developing embryo. METHODS: For this purpose, 2 strains of mice were used: SWV/Fnn (known to be sensitive to VPA) and LM/Bc (known to be resistant to VPA-induced NTDs). Pregnant females were randomly assigned to 4 experimental groups: control, VPA (600 mg/kg), INO (400 mg/kg), and VPA plus INO. VPA was injected IP at 8.5 days postcoitum (dpc). INO was administered PO twice a day from 6.5 to 10.5 dpc. At term the dams were killed, the uteri were removed, and all of the general toxicological parameters (number of implants, resorptions, dam weight, and fetus weight) were recorded and statistically analyzed. RESULTS: Postimplantation loss in the SWV/Fnn strain and NTDs in the LM/Bc strain were significantly increased after the coadministration of VPA and INO. CONCLUSIONS: This work clearly indicates that INO enhances VPA-induced teratogenicity in the mouse.  相似文献   
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DsrA RNA is an 87-nucleotide regulatory non-protein-coding RNA of Escherichia coli for which two secondary structure models (I and II) have been proposed. We have compared these models by the energy calculations, which revealed that the currently accepted model II should be rejected on the basis of thermodynamics. Here we provide new results of nuclease footprinting analysis and the application of RNA technologies that have not previously been used for DsrA RNA structural studies, such as hydrolysis with RNase H, DNAzyme, hydroxyl radicals and lead. These approaches together with bioinformatics calculations provided strong arguments for a new model III. This model clearly shows that the long U-rich region between hairpins 1 and 2 is double-stranded. These findings shed new light on DsrA RNA-Hfq interactions.  相似文献   
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This study assessed the effect of two precursors (l-phenylalanine and p-amino benzoic acid) used alone or in combination with methyl jasmonate, on the growth and accumulation of paclitaxel, baccatin III and 10-deacetylbaccatin III in hairy root cultures of Taxus x media var. Hicksii. The greatest increase in dry biomass was observed after 4 weeks of culturing hairy roots in medium supplemented with 1 μM of l-phenylalanine (6.2 g L−1). Addition of 1 μM of l-phenylalanine to the medium also resulted in the greatest 10-deacetylbaccatin III accumulation (422.7 μg L−1), which was not detected in the untreated control culture. Supplementation with 100 μM of l-phenylalanine together with 100 μM of methyl jasmonate resulted in the enhancement of paclitaxel production from 40.3 μg L−1 (control untreated culture) to 568.2 μg L−1, the highest paclitaxel content detected in the study. The effect of p-amino benzoic acid on taxane production was less pronounced, and the highest yield of paclitaxel (221.8 μg L−1) was observed when the medium was supplemented with 100 μM of the precursor in combination with methyl jasmonate.Baccatin III was not detected under the conditions used in this experiment and the investigated taxanes were not excreted into the medium.  相似文献   
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While numerous ancient human DNA datasets from across Europe have been published till date, modern-day Poland in particular, remains uninvestigated. Besides application in the reconstruction of continent-wide human history, data from this region would also contribute towards our understanding of the history of the Slavs, whose origin is hypothesized to be in East or Central Europe. Here, we present the first population-scale ancient human DNA study from the region of modern-day Poland by establishing mitochondrial DNA profiles for 23 samples dated to 200 BC – 500 AD (Roman Iron Age) and for 20 samples dated to 1000–1400 AD (Medieval Age). Our results show that mitochondrial DNA sequences from both periods belong to haplogroups that are characteristic of contemporary West Eurasia. Haplotype sharing analysis indicates that majority of the ancient haplotypes are widespread in some modern Europeans, including Poles. Notably, the Roman Iron Age samples share more rare haplotypes with Central and Northeast Europeans, whereas the Medieval Age samples share more rare haplotypes with East-Central and South-East Europeans, primarily Slavic populations. Our data demonstrates genetic continuity of certain matrilineages (H5a1 and N1a1a2) in the area of present-day Poland from at least the Roman Iron Age until present. As such, the maternal gene pool of present-day Poles, Czechs and Slovaks, categorized as Western Slavs, is likely to have descended from inhabitants of East-Central Europe during the Roman Iron Age.  相似文献   
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