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2.
I Stipani M I Capalbo V Zara 《Biochemical and biophysical research communications》1989,164(3):1281-1287
The effect of anthracycline antibiotics on the activity of the partially purified and reconstituted tricarboxylate carrier system of the rat liver mitochondria was studied. It was found that the citrate/citrate exchange activity is inhibited by Br-daunomycin and with less potency by doxorubicin, daunomycin, epirubicin and idarubicin. The inhibition of the citrate transport activity is concentration and time-dependent. Cardiolipin protects against the inhibition by Br-daunomycin and the reconstituted citrate transport activity depends upon the ratio of cardiolipin/Br-daunomycin. 相似文献
3.
Yeast mitochondria lacking the phosphate carrier/p32 are blocked in phosphate transport but can import preproteins after regeneration of a membrane potential. 总被引:4,自引:1,他引:3
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V Zara K Dietmeier A Palmisano A Vozza J Rassow F Palmieri N Pfanner 《Molecular and cellular biology》1996,16(11):6524-6531
Two different functions have been proposed for the phosphate carrier protein/p32 of Saccharomyces cerevisiae mitochondria: transport of phosphate and requirement for import of precursor proteins into mitochondria. We characterized a yeast mutant lacking the gene for the phosphate carrier/p32 and found both a block in the import of phosphate and a strong reduction in the import of preproteins transported to the mitochondrial inner membrane and matrix. Binding of preproteins to the surface of mutant mitochondria and import of outer membrane proteins were not inhibited, indicating that the inhibition of protein import occurred after the recognition step at the outer membrane. The membrane potential across the inner membrane of the mutant mitochondria was strongly reduced. Restoration of the membrane potential restored preprotein import but did not affect the block of phosphate transport of the mutant mitochondria. We conclude that the inhibition of protein import into mitochondria lacking the phosphate carrier/p32 is indirectly caused by a reduction of the mitochondrial membrane potential (delta(gamma)), and we propose a model that the reduction of delta(psi) is due to the defective phosphate import, suggesting that phosphate transport is the primary function of the phosphate carrier/p32. 相似文献
4.
Richard S. Dodd Franois Fromard Zara A. Rafii Franois Blasco 《Biochemical Systematics and Ecology》1995,23(7-8):859-868
Foliage from 21 red mangroves (Rhizophora mangle, R. racemosa and R. x harrisonii) from different ecogeographic conditions in Gabon, West Africa, was analyzed for epicuticular wax composition using CC, GC and GC-MS. Aliphatic hydrocarbons ranging from C23 to C34 and some triterpenoids were identified. Alkanes were the major constituents (46.7–99.9%), with triterpenoids also accounting for up to 53.3% of the wax extract. High contents of octacosane (27.2%) and lower amounts of nonacosane (14.9%) and hentriacontane (9.8%) distinguished R. mangle from the other two species. R. hizophora x harrisonii was exceptionally rich in nonacosane (45.3%) with moderately high concentrations of hentriacontane (25.4%), whereas R. racemosa was intermediate between the two former species in its content of these three alkanes. Inclusion of the less abundant constituents in principal components analysis provided a good separation of R. x harrisonii, whereas the two other species showed some degree of overlap. Although major alkane patterns can be used to discriminate among the Rhizophora species examined, we do find substantial intra-specific variation that may be attributable to population genetic variation; this was least for R. x harrisonii. The hybrid status of this latter species could not be confirmed from the biochemical analyses carried out. 相似文献
5.
A fast purification procedure for the isolation and purification of eukaryotic porin (De Pinto et al., (1987) Biochim. Biophys. Acta 905, 499-502) was applied to liver mitochondria of the fish Anguilla anguilla. A protein preparation was obtained which formed slightly anionically selective pores in reconstitution experiments with lipid bilayer membranes. The distribution of single-channel conductances had two maxima of 2.4 nS and 4.0 nS in 1 M KCl. Sodium dodecylsulfate electrophoretograms of the protein preparation showed the presence of two bands of very similar electrophoretic mobility (32 and 32.5 kDa). Both bands cross-reacted with antibodies raised against purified bovine heart porin and with antibodies raised against the 19 amino acids N-terminal end of human porin. No cross-reactivity was observed with antibodies against yeast porin. The peptide maps of the two bands showed slight differences. The possibility of the presence of two different porins in liver mitochondria of Anguilla anguilla is discussed. An extensive immunological comparison of different mitochondrial porins is presented. 相似文献
6.
We studied distribution of mRNA for nuclear protooncogene c-myc and nuclear protein P-53 in mature oocytes and embryos of Xenopus laevis from the stage of fertilization up to the stage of hatching by in situ hybridization with histological sections. mRNA for c-myc was present in all cells of the embryo at all studied developmental stages. Between the stage of fertilization and up to the late blastula, mRNA concentration for c-myc decreased progressively in all embryonic cells. During gastrulation a local increase in the concentration of this messenger was found in dorsal mesoderm and ectoderm. At the stage of neurula increased concentration of mRNA for c-myc was observed in all cells of the embryo but the hybridization signal increased particularly distinctly in cells of the neural tube. In studies of P-53 mRNA distribution hybridization signal was detected only in brain cells after stage 20 of development (after closure of the neural folds) and up to the stage of hatching. 相似文献
7.
Nathan Ford Zara Shubber Andrew Hill Marco Vitoria Meg Doherty Edward J. Mills Andy Gray 《PloS one》2013,8(11)
Introduction
Lamivudine and emtricitabine are considered equivalent by several guidelines, but evidence of comparable efficacy is conflicting.Methods
We searched two databases up to June 30 2013 to identify randomized and quasi-randomized trials in which lamivudine and emtricitabine were used as part of combination antiretroviral therapy for treatment-naïve or experienced HIV-positive adult patients. We only included trials where partner drugs in the regimen were identical or could be considered to be comparable. We allowed for comparisons between tenofovir and abacavir provided the study population did not begin treatment with a viral load >100,000 copies/ml.Results
12 trials contributed 15 different randomized comparisons providing data on 2251 patients receiving lamivudine and 2662 patients receiving emtricitabine. Treatment success was not significantly different in any of the 12 trials. In the three trials that directly compared lamivudine and emtricitabine, the relative risk for achieving treatment success was non-significant (RR 1.03 95%CI 0.96-1.10). For all trials combined, the pooled relative risk for treatment success was not significantly different (RR 1.00, 95%CI 0.97–1.02). No heterogeneity was observed (I 2 = 0). Similarly, there was no difference in the pooled relative risk for treatment failure (RR 1.08, 95%CI 0.94–1.22, I 2 = 3.4%).Conclusions
The findings of this systematic review suggest that lamivudine and emtricitabine are clinically equivalent. 相似文献8.
Pseudomonas community structures were investigated by analyzing 16S rRNA clone libraries derived from fertilized and unfertilized soil plots under corn–alfalfa rotation in a long-term experiment. Amplified 16S rRNA fragments derived by polymerase chain reaction (PCR) were cloned and sequenced. A total of 729 clone sequences were analyzed, of which 51 were possible chimeras and discarded. The remaining clone sequences (678) belonged to γ-proteobacteria with 61.8 % (419) classified to the genus Pseudomonas. Unclassified Gammaproteobacteria accounted for 23.4 % of total clones sequences. Rarefaction analyses showed a more diverse community structure of both Gammaproteobacteria and Pseudomonas in unfertilized than fertilized field soils irrespective of plant types under cultivation. Bacterial or Pseudomonas community structures differed significantly between fertilized and unfertilized soil plots. Clone sequences that are affiliated to Pseudomonas putida and P. oryzihabitans were more prominent in libraries from fertilized plots, while those that clustered with Pseudomonas frederiksbergensis were more often retrieved from unfertilized soil plots. A strong influence of fertilizer applications on community structure was supported by principal component analysis. We conclude that long-term use of mineral fertilizers could influence Pseudomonas community structure. 相似文献
9.
Yan Guo Mary A. Johnson Zara Mehrabian Manoj K. Mishra Rangaramanujam Kannan Neil R. Miller Steven L. Bernstein 《PloS one》2016,11(4)
IntroductionPolyamidoamine dendrimer nanoparticles (~ 4 nanometers) are inert polymers that can be linked to biologically active compounds. These dendrimers selectively target and accumulate in inflammatory cells upon systemic administration. Dendrimer-linked compounds enable sustained release of therapeutic compounds directly at the site of damage. The purpose of this study was to determine if dendrimers can be used to target the optic nerve (ON) ischemic lesion in our rodent and nonhuman primate models of nonarteritic anterior ischemic optic neuropathy (NAION), a disease affecting >10,000 individuals in the US annually, and for which there currently is no effective treatment.MethodsNAION was induced in male Long-Evans rats (rNAION) and in one adult male rhesus monkey (pNAION) using previously described procedures. Dendrimers were covalently linked to near-infrared cyanine-5 fluorescent dye (D-Cy5) and injected both intravitreally and systemically (in the rats) or just systemically (in the monkey) to evaluate D-Cy5 tissue accumulation in the eye and optic nerve following induction of NAION.ResultsFollowing NAION induction, Cy-5 dendrimers selectively accumulated in astrocytes and circulating macrophages. Systemic dendrimer administration provided the best penetration of the ON lesion site when injected shortly after induction. Systemic administration 1 day post-induction in the pNAION model gave localization similar to that seen in the rats.ConclusionsDendrimers selectively target the ischemic ON lesion after induction of both rNAION and pNAION. Systemic nanoparticle-linked therapeutics thus may provide a powerful, targeted and safe approach to NAION treatment by providing sustained and focused treatment of the cells directly affected by ischemia. 相似文献
10.
Water quality and phytoplankton community structure in mangrove streams under different logging regimes in Cameroon
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Ambo Beatrice Fonge Pascal Tabi Tabot Coleen Mumbang Chop Adeline Mange 《African Journal of Ecology》2016,54(1):39-48
Mangrove logging is rampant, and its effects on phytoplankton dynamics have not been investigated. Phytoplankton are valuable in biomonitoring pollution in mangrove ecosystems. This study assessed the relationship between physico‐chemical characteristics of the water and observed phytoplankton community structure, in relation to anthropogenic activities. Water samples were collected from seven sites within the mangrove ecosystem that differed in wood harvesting age and proximity to human settlements. Characterization of samples followed standard methods. pH of all water samples indicated acidity. Phytoplankton species richness and soluble P were positively correlated (r = 0.822, P ≤ 0.023), but no correlations existed with logging age (r = ?0.273, P = 0553). The site with highest soluble phosphorus concentration (Site 4) had highest phytoplankton abundance, diversity and richness. A total of 127 species were identified in 58 families. Euglenaceae was the most abundant family (13 species) and Anacystis sp. the most frequent species (100%). The most common genera were Microcystis and Anacystis, bioindicators of pollution. The site at which harvesting was most recently performed had more eutrophic species, while site harvested earliest (Site 5) had the least. These results are discussed with respect to how anthropogenic activities influence water quality, phytoplankton community structure, mangrove conservation and management. 相似文献